Interbed Systems Incorporation by gbp12616

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									                                                                                                             SMRIBIBL




Author                     Year   Title                                                                                                  Source                                                     Sort              Language
Alla, N.;                                                                                                                                Proc. 3rd. Conf. Mechanical Behavior of Salt, Palaiseau,
Bérest, P. et al.           1993 In situ tests in brine-filled caverns                                                                   14.-16.09.93, pp.445-454                                   Paper




Baes, C. F.;
Gilpatrick, L. O. et al.    1983 The effect of water in salt repositories, final report                                                  Oak Ridge : Oak Ridge National Laboratory, ORNL-5950 Report




Beauheim, R. L.;                 Interpretation of brine-permeability tests of the Salado formation at the Waste Isolation Pilot Plant site:
Saulnier, G. J. et al.      1991 First interim report                                                                                        Albuquerque : Sandia Nat. Lab., SAND90-0083            Report

Bérest, P.;
Bergues, J. et al.          1996 A tentative evaluation of the MIT                                                                       SMRI Spring Meeting, Houston, 14.-17.04.96                 Paper

Bérest, P.;
Brouard, B. et al.          1995 Behaviour of sealed solution-mined caverns                                                              SMRI Spring Meeting, New Orleans, 1995                     Paper




Bérest, P.;
Brouard, B. et al.          1995 Some comments on the MIT test                                                                           SMRI Fall Meeting, San Antonio, 22.-25.10.95               Paper




Bérest, P.;                                                                                                                              Proc. 7th. Symp. on Salt, Kyoto, 1993, Vol. 1, pp. 353-
Blum, P. A.                 1993 In situ tests in salt caverns                                                                           362                                                        Paper

Borns, D. J.;                                                                                                                            Proc. 30th. U.S. Symp. Rock Mechanics, Morgantown,
Stormont, J. C.             1989 The delineation of the disturbed rock zone surrounding excavations in salt                              19.-22.06.89, pp. 353-360                                  Paper


Boulanger, A.;
Rousseau, A. J.             1991 Method of rapidely abandoning large cavities washed-out in rock salt                                    US 5 004 298                                               Patent

                                                                                                                                         EOS Transact., Am. Geophys. Union 69 (1988) 9, pp.121
Bredehoeft, J. D.           1988 Will salt repositories be dry ?                                                                         + 131                                                 Journal Article
Bredehoeft, J. D.;
Papadopulos, S. S.          1980 A method for determining the hydraulic properties of tight formations                                   Water Res. Res. 16 (1980) 1, pp. 233-238                   Journal Article

Bush, D. D.;                                                                                                                             Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 26 (1989)
Barton, N.                  1989 Application of small scale hydraulic fracturing for stress measurements in bedded salt                  6, pp.629-635                                            Journal Article


Cauberg, J.;
Walters, J. V. et al.       1986 Rock mechanical behaviour and sealing aspects of a closed-in salt cavity filled with brine (SMRI)       SMRI Fall Meeting, Amsterdam, 21.-24.09.86                 Paper


Clark, J. E.;
Papadeas, P. W. et al.      1991 Gulf Coast borehole closure test well Orangefield, Texas                                                SMRI Fall Meeting, Las Vegas, 27.-19.10.91                 Paper




Doe, T. W. ;                                                                                                                             Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 26 (1989)
Boyce, G.                   1989 Orientation of hydraulic fractures in salt under hydrostratic and non hydrostratic stresses             6, pp. 605-611                                           Journal Article




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                                                                                                                             SMRI Fall Meeting, Hannover, 1994 / SMRI Res. Proj.
Durup, J. G.          1994 Long-term tests for tightness evaluations with brine and gas in salt (Field test n° 2 with gas)   Rep. No. 94-0002-S                                         Paper + SMRI-Report

                           Essais de perméabilité dans un massif salifère                                                    Ann. Ass. Franc. Techn. Petrol. Conf. / Pétrol. Tech. 387,
Durup, J. G.          1994 [Permeability tests in a salt mass]                                                               pp.17-20                                                   Journal Article        french




Ehgartner, B.;
Linn, J. K.           1994 Mechanical behavior of sealed SPR caverns                                                         SMRI Spring Meeting, Houston, 25.-27.04.94                 Paper


Finley, R. E.;
Zeuch, D. H. et al.   1994 Sealing of boreholes using natural, compatible materials: granular salt                           Eurock '94, Delft, 29.-31-08.94, pp. 753-760               Paper




Fischle, W. R.;
Stöver, W. H.         1986 Construction of a bulkhead and measurement under brine pressure                                   SMRI Fall Meeting, Amsterdam, 21.-24.09.86                 Paper




Fokker, P. A.         1995 The behaviour of salt and salt caverns                                                            Delft : Techn. Univ.                                       Thesis


Fokker, P. A.;
Kenter, C. J..        1994 The micro mechanical description of rocksalt plasticity                                           Proc. Eurock '94, Delft, 29.-31.08.94, pp.705-713          Paper

                           Durchlässigkeits-und Rißbildungsuntersuchungen zum Nachweis der Dichtheit von Salzkavernen
Förster, S.           1974 [Permeability and fracturing investigations to verify the tightness of salt caverns]              Neue Bergbautechn. 4 (1974) 4, pp. 278-283                 Journal Article        german
Fuenkajorn, K.;
Daemen, J. J. K.      1996 Sealing of boreholes in rock: an overview                                                         in: Aubertin et.al.: Rock Mechanics, 1996, pp.1447-1454    Paper


Garg, S. K.;
Nur, A.               1973 Effective stress law for fluid-saturated porous rocks                                             J. Geophys. Res. 78 (1973) 26, pp. 5911-5921               Journal Article




Gaz de France         1990 Field tests in well EZ 58                                                                         SMRI Res. Proj. Rep. No. 90-0002-S                         SMRI Research Report




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Gloyna, E. F.;
Reynolds, T. D.          1961 Permeability measurements of rock salt                                                               J. Geophys. Res. 66 (1961) 11, pp. 3913-3921                Journal Article


                                                                                                                                   Proc. 2nd. Conf. Mechanical Behavior of Salt, Hannover,
Horseman, S. T.          1988 Moisture content - a major uncertainty in storage cavity closure prediction                          24.-28.09.84, pp. 53-68                                     Paper




Horseman, S. T.;
Russell, J. E. et al.    1993 Slow experimental deformation of Avery Island salt                                                   Proc. 7th. Symp. on Salt, Kyoto, 1993, Vol. 1, pp. 67-74    Paper




Howarth, S. M.;               Interpretation of in situ pressure and flow measurements of the Salado formation at the Waste Isolation
Peterson, E. W. et al.   1991 Pilot Plant                                                                                             SPE Paper 21840                                          Paper
Jäpel, G.;                    Verfahren zur Endverwahrung von Salzkavernen
Fritze, P. et al.        1991 [Method for the maintenance of shut in salt caverns]                                                    DE 41 04 383 C2                                          Patent             german


Jenyon, M. K.            1986 Salt with a pinch of water                                                                           Nature 324 (1986), 11.Dec., pp.515-516                      Journal Article


Kenter, C. J.;
Doig, S. J. et al.       1990 Diffusion of brine through rock salt roof of caverns                                                 SMRI Fall Meeting, Paris, 14.-19.10.90                      Paper

                                                                                                                                   Proc. 2nd. Conf. Mechanical Behavior of Salt, Hannover,
Kiersten, P.             1988 Laboratory hydraulic fracturing experiments in rock salt                                             24.-28.09.84, pp. 223-233                                   Paper




Lai, C. S.               1971 Fluid flow through rock salt under various stress states                                             Ann Arbor : Michigan State Univ.                            Thesis




Langer, M.               1993 Use of solution-mined caverns in salt for oil and gas storage and toxic waste disposal in Germany    Eng. Geol. 35 (1993) 3-4, pp.183-190                        Journal Article

Langer, M.;                   Gebirgsmechanische Bearbeitung von Stabilitätsfrage bei Deponiekavernen im Salzgebirge
Wallner, M. et al.       1984 [Rock mechanical elaboration of stability aspects in rock salt repository caverns]                   Kali u. Steinsalz (1984) 2, pp.66-76                        Journal Article    german




                                                                                                                                   in: Suitability of solution-mined caverns for oil and gas
Linn, J. K.              1995 Closure and plugging of a cavern disposal well in domal salt                                         waste disposal, 13.09.95, Railroad Comm. Texas, p.27        Paper (Abstract)




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Miehe, R.;                   Permeabilitätsbestimmungen im Staßfurt-Steinsalz in Abhängigkeit von einer Streckenauffahrung
Harborth, B. et. al.    1993 [Permeability determination in Staßfurt rock salt depending on roadway drifting]                        Kali u. Steinsalz 11 (1993) 5/6, pp.175-184                Journal Article     german




Morgan, H. S.;               Computed and measured response of a thick-walled hollow cylinder of salt subjected to both              Proc. 30th. U.S. Symp. Rock Mechanics, Morgantown,
Wawersik, W. R.         1989 homogeneous and inhomogeneous loading                                                                   19.-22.06.89                                               Paper


Morgenstern, N. R.;                                                                                                                  Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 28 (1991)
Sepehr, K.              1991 Time-dependent hydraulic fracturing in potash mines                                                     2/3, pp. 187-197                                         Journal Article

Munson, D. E.;                                                                                                                       Proc. 3rd. Conf. Mechanical Behavior of Salt, Palaiseau,
DeVries, K. L. et al.   1993 Extension of the M-D model for treating stress drops in salt                                            14.-16.09.93, pp.31-44                                     Paper


                             Numerische Analyse geomechanischer Wechselwirkungen bei der Endablagerung von Sonderabfall in
                             Salzkavernen
                             [Numerical analysis of geomechancial interactions during final disposal of hazardous waste in salt Hannover : Univ., Fachber. Bauing.- u.
Naujoks, A.             1989 caverns]                                                                                           Vermessungswesen; Forsch.-Erg. 13                               Thesis (Abstract)   german




Nowak, E. J.;
McTigue, D. F.          1987 Interim results of brine transport studies in the Waste Isolation Pilot Plant (WIPP)                    Albuquerque : Sandia Nat. Lab., SAND 87-0880               Report


Niou, S.;                                                                                                                            Waste Management '89 Sympl., Tucson, 26.02.-02.03.89,
Deal, D. E.             1989 Migration of brine and nitrogen in creeping salt                                                        Vol. 1, pp. 329-335                                   Paper


Nur, A.;
Byerlee, J. D.          1971 An exact effective stress law for elastic deformation of rock with fluids                               J. Geophys. Res. 76 (1971) 26, pp. 6414-6419               Journal Article


Paterson, M. S.         1983 The equivalent channel model for permeability and resistivity in fluid-saturated rock, a re-appraisal   Mech. of Materials 2 (1983), pp.345-352                    Journal Article




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Peach, C. J.;                                                                                                                        Luxembourg : Comm. Europl. Comm. Rep. EUR 10926
Spiers, C. J. et al.         1987 Fluid and ionic transport properties of deformed rock salt                                         EN                                                    Report




                                                                                                                                     Geologica Ultraiectina, Med. Fac. Aardwetenschappen
Peach, C. J.                 1991 Influence of deformation on the fluid transport properties of salt rocks                           No.77, Techn. Univ. Utrecht                           Thesis
Peterson, E. W.;
Lagus, P. L.                 1988 Testing of borehole plugs placed in bedded halite and anhydrite                                    SMRI Spring Meeting, Mobile, 25.04.88                 Paper




Peterson, E.;
Lagus, P. et al.             1985 WIPP horizon in situ permeability measurements: final report                                       Albuquerque : Sandia Nat. Lab., SAND85-7166           Report




                                  Some basic stress-diffusion solutions for fluid-saturated elastic porous media with compressible
Rice, J. R.; Cleary, M. P.   1976 constituents                                                                                       Rev. Geophys. Space Phys. 14 (1976), pp. 227-241      Journal Article

Saalbach, B.;                     Verfahren zur Endverwahrung von Kavernen im Carnallititgestein [Procedure for abandonment of
Grüschow, N. et al.          1990 caverns in carnallite rock]                                                                        DD 294 994 A5                                         Patent            german




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                                     Permeability study in relation to stress state and cavern design. Phase I: Constitutive equation of Finite
Serata, S.;                          Element Program GEO. Phase II: Finite Element Model to predict permeability increase around salt
Fuenkajorn, K.                  1993 cavern                                                                                                     SMRI Res. Proj. Rep. No. 91-001 A-S                    SMRI Research Report




Spiers, C. J.;
Schutjens, P. M. T. M. et al.   1990 Experimental determination of constitutive parameters governing creep of rocksalt by pressure solution Geol. Soc. Spec. Publ. No. 54, pp. 215-227                 Paper




Spiers, C. J.;
Urai, J. L. et al.              1987 The influence of fluid-rock interaction on the rheology of salt rock                                    Luxembourg : Comm. Europl. Comm. Rep. EUR10399            Report (Abstract)




                                                                                                                                             Albuquerque : Sandia Nat. Lab., Memorandum to
Stormont, J. C.                 1991 An approach to address DRZ (disturbed rock zone) development and healing in rock salt                   distribution                                              Paper




Stormont, J. C.;
Howard, C. L. et al.            1991 In situ measurements of rock salt permeability changes due to nearby excavation                         Albuquerque : Sandia Nat. Lab., SAND90-3134               Report




Stormont, J. C.                 1990 Gas permeability changes in rock salt during deformation                                                Univ. of Arizona, Dept. Min. Geol. Eng.                   Thesis




Stormont, J. C.                 1990 Summary of 1988 WIPP facility horizon gas flow measurements                                             Albuquerque : Sandia Nat. Lab., SAND89-2497               Report




Stormont, J. C.;
Peterson, E. W. et al.          1987 Summary of and observations about WIPP facility horizon flow measurements through 1986                  Albuquerque : Sandia Nat. Lab, SAND87-0176                Report


Stormont, J. C.                 1996 The influence of rock salt disturbance on sealing                                                       in: Aubertin et.al.: Rock Mechanics, 1996, pp. 1471-1477 Paper


Stormont, J. C.;                                                                                                                             Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 29 (1992)
Daemen, J. J. K.                1992 Laboratory study of gas permeability changes in rock salt during deformation                            4, pp. 325-342                                           Journal Article

Stormont, J. C.;                                                                                                                             in: Roegiers: Rock Mechanics as a multidisciplinary
Howard, C. L. et al.            1991 Changes in rock salt permeability due to nearby excavation                                              Science, pp. 899-907                                      Paper

Sutherland, H. J.;                                                                                                                           Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 17 (1980),
Cave, S. P.                     1980 Argon gas permeability of New Mexico rock salt under hydrostatic compression                            pp. 281-288                                               Journal Article

Sutherland, H. J.;
Cave, S. P.                     1979 Gas permeability of SENM rock salt                                                                      Albuquerque : Sandia Nat. Lab., SAND78-2287J              Report




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Thoms, R. L.           1980 Permeability of rock salt for compressed air energy storage                                             SMRI Fall Meeting, Minneapolis, 12.-15.10.80             Paper
Thoms, R. L.;
Gehle, R. M.           1990 Hydrofrac gradients in two US salt domes (SMRI)                                                         SMRI Fall Meeting, Paris, 14.-17.10.90                   Paper




Tsenn, M. C.;                                                                                                                       Scripta Metallurgica et Materialia 24 (1990), pp.1115-
Carter, N. L.          1990 Strengthening effect of dislocation networks in NaCl                                                    1118                                                     Journal Article




Urai, J. L.;
Spiers, C. J. et al.   1986 Weakening of rock salt by water during long-term creep                                                  Nature 324 (1986) Dec. 11, pp.554-557                    Journal Article




                            Deformation of wet salt rock. An investigation into the interaction between mechanical properties and
                            microstructural processes during deformation of polycrystalline carnallite and bischofite in the
Urai, J. L.            1983 presence of a pore fluid                                                                                Utrecht : Univ.                                          Thesis




Van Fossan, N. E.      1981 Mechanisms of product leakage from solution caverns                                                     SMRI Spring Meeting, 27.04.81                            Paper




Varo, L.;                                                                                                                           Proc. Conf. on Rock Engineering, Newcastle upon Tyne,
Passaris, E. K. S.     1977 The role of water in the creep properties of halite                                                     04.-07.04.77, pp.85-100                                  Paper




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                                                                                                                                              2nd. Europ. Comm. Conf. on Radioactive waste
Vons, L. H.;                                                                                                                                  management and disposal, Luxembourg, 22.-26.04.85,
Andre Jehan, R. et al.           1985 Specific investigations related to salt rock behaviour                                                  Summary Paper VI.2                                        Paper (Abstract)

                                                                                                                                              Proc. 2nd. Conf. Mechanical Behavior of Salt, Hannover,
Wallner, M.                      1988 Frac-pressure risk for cavities in rock salt                                                            24.-28.09.84, pp. 645-658                                 Paper
                                                                                                                                              Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 18 (1981),
Walsh, J. B.                     1981 Effect of pore pressure and confining pressure on fracture permeability                                 pp.429-435                                                Journal Article




Wawersik, W. R.;                      A characterization of pressure records in inelastic rock, demonstrated by hydraulic fracturing          Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 26 (1989)
Stone, C. M.                     1989 measurements in salt                                                                                    6, pp.613-627                                            Journal Article


You, T.;
Maisons, C. et al.               1994 Experimental procedure for the closure of brine production caverns on the "Saline de Vauvert" site      SMRI Fall Meeting, Hannover, 25.09.-01.10.94              Paper




Nowak, E. J.;
McTique, D. F. et al.            1988 Brine inflow to WIPP disposal rooms: Data, modeling, and assessment                                     Albuquerque : Sandia Nat. Lab., SAND 88-0112              Report




Van Sambeek, L. L.               1990 A simple method for modeling the pressure buildup or flow of an abandoned solution well                 SMRI Spring Meeting, Austin, 24.04.1990                   Paper
                                      Gasdruckbelastbarkeit und Rißbildung der für die unterirdische Gasspeicherung in Kavernen
                                      bedeutsamen Salinargesteine des Zechsteins
                                      [Stressability by gas pressure and fracturing of evaporites of Zechstein-formation relevant to gas
Förster, S.                      1985 cavern storage]                                                                                         Freiberger Forsch.-H. A 724                               Report (Abstract)   german

Faske, B.;                            Vorrichtung zum Einbringen eines Dichtmittels in ein Bohrloch
Stein-Lausnitz, E.-G.v. et al.   1987 [Apparatus to inject a sealant into a well]                                                             DD 262 887 A1                                           Patent                german
Hambley, D. F.;                                                                                                                               Key questions in rock mechanics: Proc. 29th U.S. Symp.,
Dusseault, M. B. et al.          1988 Characterization of saltrock creep behavior                                                             pp.179-189                                              Paper

                                                                                                                                              Key questions in rock mechanics: Proc. 29th U.S. Symp.,
Van Sambeek, L. L.               1988 Mechanical behavior and performance of concrete seals in rock salt                                      pp.665-672                                              Paper

Borgmeier, M.;                        Gaspermeabilitätsmessungen an homogenen Modellsalzkernen
Weber, J. R.                     1992 [Permeability investigations of homogenous model salt cores]                                            Erdöl Erdgas Kohle 108 (1992) 10, pp. 412-414             Journal Article     german




Chester, F. M.;                       Frictional faulting in polycrystalline halite: correlation of microstructure, mechanisms of slip, and   American Geophysical Union: Geophysical Monograph
Logan, J. M.                     1990 constitutive behavior                                                                                   56, pp. 49-65                                             Paper




                                      Untersuchungen zum belastungsabhängigen Durchlässigkeitsverhalten von Salzgestein unter
                                      besonderer Berücksichtigung der Porenraumbeladung
                                      [Investigations on the load-dependent permeability behavior of saliferous rock focusing on pore space   Clausthal-Zellerfeld : Techn. Univ., Fak. f. Bergbau,
Borgmeier, M.                    1992 loading]                                                                                                Hüttenwesen u. Maschinenwesen                             Thesis (Abstract)   german




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Bosworth, W.            1981 Strain-induced preferential dissolution of halite                                               Tectonophys. 78 (1981), pp. 509-525                        Journal Article
Cosenza, P.;                                                                                                                 Proc. 3rd Conf. Mech. Behavior of Salt, Palaiseau, 14.-
Ghoreychi, M.           1993 Coupling between mechanical behavior and transfer phenomena in salt                             16.09.93, pp. 271-293                                      Paper




Aubertin, M.;
Gill, D. E. et al.      1991 An internal variable model for the creep of rock salt                                           Rock Mech. Rock Eng. 24 (1991), pp. 81-97                  Journal Article




Langer, M.;
Wallner, M.             1988 Solution-mined salt caverns for the disposal of hazardous chemical wastes                       Bull. IAEG No. 37 (1988), pp. 61-69                        Journal Article

Hunsche, U.;
Schulze, O.             1993 Effect of humidity and confining pressure on creep of rock salt                                 Proc. 3rd Conf. Mechan. Behavior of Salt, pp. 223-234    Paper
Van Sambeek, L. L.;                                                                                                          Int. J. Rock Mech. Min. Sci. & Geomech. Abstr. 30 (1993)
Ratigan, J. L. et al.   1993 Dilatancy of rock salt in laboratory tests                                                      7, pp. 735-738                                           Journal Article




Borns, D. J.            1983 Petrographic study of evaporite deformation near the Waste Isolation Pilot Plant (WIPP)         Albuquerque : Sandia Nat. Lab., SAND83-0166                Report




Borns, D. J.            1987 Rates of evaporite deformation: The role of pressure solution                                   Albuquerque : Sandia Nat. Lab., SAND85-1599                Report


Allemandou, X.;                                                                                                              Proc. 3rd. Conf. Mechanical Behavior of Salt, Palaiseau,
Dusseault, M. B.        1993 Procedures for cyclic creep testing of salt rock, results and discussions                       14.-16.09.93, pp.193-204                                   Paper

Arnold, W.;
Förster, S. et al.      1974 In situ investigations of fracturing in salt cavities for determining stress components         9th World Oil Congress, Tokyo, 1974, PD21 (3), pp.89-96 Paper
Bazargan, W.;                                                                                                                Proc. 4th Progress Meeting PEGASUS, Exeter, 26.-
Telandro, S. et al.     1994 In situ gas and brine permeability test in salt: design and deployment of experimental device   27.06.94, EUR 16001, pp.171-183                         Paper
Bérest, P.;
Brouard, B.             1996 Behavior of sealed solution-mined caverns                                                       Proc. ISRM Int. Symp., Eurock '96, pp.1127-1131            Paper


Cosenza, P.;                 Évolution de la perméabilité du sel gemme sous sollicitations mécano-chimiques
Ghoreychi, M.           1997 [Permeability evolution of rock salt under mechano-chemical stresses]                           Bull. Soc. Géol. France; in Press                          Journal Art.(Abstr.)




Cosenza, P.;                 Mesure de la perméabilité in situ du sel
Ghoreychi, M. et al.    1997 [In situ permeability measurement in salt]                                                      Rev. Franc. Géotechn.; in Press                            Journal Art.(Abstr.)




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Cosenza, P.;                                                                                                                       Proc. 4th Conf. Mechanical Behavior of Salt, Montreal,
Ghoreychi, M. et al.    1996 In situ gas and brine permeability measurements in salt                                               1996; in Press                                             Paper




Cosenza, P.;                                                                                                                       Proc. 5th Progress Meeting PEGASUS, EUR 16746,
Ghoreychi, M. et al.    1995 First results and interpretation of in situ permeability measurement in salt to gas and to brine      pp.167-175                                                 Paper

                                                                                                                                   Maury; Fourmaintraux (Eds.): Rock at great depth, 1989,
Dusseault, M. B.        1989 Saltrock behavior as an analogue to the behavior of rock at great depth                               pp.11-17                                                   Paper

                             Zur Ermittlung der Gasdruckbelastbarkeit des Werrasteinsalzes und der Ableitung zulässiger
Jäpel, G.;                   maximaler Betriebsdrücke für die Kavernenspeicheranlage Xanten
Schmidt, T. et al.      1990 [The determination of the maximum gas pressure capacity of the salt and the deduction ...]            Erdöl Erdgas Kohle 106 (1990) 4, pp.155-161                Journal Article     german




                             Gebirgsmechanische Untersuchungen zur Bestimmung des Maximaldrucks von Salzkavernen                   Hannover : Univ., Forschungsergebnisse a.d. Tunnel- u.
Struck, D.              1993 [Rock mechanical tests to determine the maximum pressure of salt caverns]                             Kavernenbau H.15                                           Report              german
Thorel, L.;                                                                                                                        Proc. 3rd. Conf. Mechanical Behavior of Salt, Palaiseau,
Ghoreychi, M.           1993 Rock salt damage. Experimental results and interpretation                                             14.-16.09.93, pp.161-175                                   Paper

Urai, J. L.;                 Deformation mechanisms operating in naturally deformed halite rocks as deduced from microstructural
Spiers, C. J. et al.    1987 investigations                                                                                      Geol. Mijnbouw 66 (1987), pp.165-176                         Journal Article


                             Mesure de la perméabilité de roches très peu perméables et étude de son évolution sous sollicitations
                             thermomécaniques
                             [The permeability measurement in ultralow permeability rocks and the study of the evolution under
Le Guen, C.             1991 thermomechanical stresses]                                                                            Paris : École Nat. Supérieure des Mines                    Thesis (Abstract)   french




                             Sur les couplages entre comportement mécanique et processus de transfert de masse dans le sel
                             gemme
Cosenza, P.             1996 [Coupled effects between mechanical behavior and mass transfer phenomena in rock salt]                Paris : Univ.                                              Thesis              french


Trimmer, D.             1982 Laboratory measurements of ultralow permeability of geologic materials                                Rev. Sci. Instrum. 53 (1982) 8, pp.1246-1254               Journal Article




Chan, K. S.;                                                                                                                       Computational Mechanics '95, Proc. Int. Conf. Comp.
DeVries, K. L. et al.   1995 A damage mechanics approach to life prediction for a salt structure                                   Eng. Sci., Hawaii, 30.07.-03.08.95, Vol.1, pp.1140-1145    Paper
                             Langzeitsichere Verschlüsse für Untertagedeponien und Endlager unter besonderer Berücksichtigung
Sitz, P.;                    natürlicher Materialien
Gruner, M.              1996 [Long term seals for underground repositories focusing on natural materials]                          Glückauf 132 (1996) 7, pp.327-332                          Journal Article     german




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Peach, C. J.;                     Influence of crystal plastic deformation on dilatancy and permeability development in synthetic salt
Spiers, C. J.                1996 rock                                                                                                        Tectonophys. 256 (1996), pp.101-128                  Journal Article




Mazariegos, R. A. et al.     1996 Modeling the evolution of salt structures using nonlinear rocksalt flow laws                                Tectonophys. 256 (1996), pp.101-128                  Journal Article


Gniady, C. T.;
Ehgartner, B. L.             1993 Fracture predictions for over-pressurization of sealed wellbores                                            SMRI Fall Meeting, Lafayette, 24.-28.10.93           Paper


Thoms, R. L.; Gehle, R. M.   1986 Hydrofracture gradients in salt domes                                                                       SMRI Fall Meeting, Amsterdam, 22.09.86               Paper




                                  Panel discussion questions plugging brine filled solution mined chamber, and comments related to
Van Fossan, N.               1988 panel discussion on plugging of wells                                                                       SMRI Spring Meeting, 1988                            Paper
Thoms, R. L.; Gehle, R. M.   1984 Progress report. Hydrofrac gradients in salt domes                                                          SMRI Fall Meeting, 1984                              Paper
Munson, D. E.;
DeVries, K. L. et al.              Measured and calculated closures of open and brine filled shafts and deep vertical boreholes in salt       DOE Contract No. DE-AC04-76DP00789                   Report (Abstract)




Biggers, J. V.;
Dayton, G. O.                1982 Brine migration in hot-pressed polycrystalline sodium chloride                                              ONWI-415                                             Report




Wawersik, W. R.;                  Application of hydraulic fracturing to determine virgin in situ stress state around Waste Isolation Pilot
Stone, C. M.                 1985 Plant - in situ measurements                                                                                Albuquerque : Sandia Nat. Lab., SAND85-1776          Report




                                                                                                                                              Berkeley : Serata Geomech. Inc., SMRI Research Project
Serata Geomechanics, Inc.    1984 Ultimate stress in the salt envelope of a sealed liquid-filled solution cavern. Final report                Report 84-0004-S                                       SMRI Research Report




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                                             Bestimmung des Diffusions- und Permeabilitätsverhaltens von Wasserstoff in Steinsalz und
                                             kompaktiertem Salzgrus                                                                                 Battelle Ingenieurtechn. GmbH, BMBF-
Battelle Ingenieurtechnik GmbH et al.   1995 [Determining diffusion and permeability behaviour of hydrogen in rock salt and compacted salt fines]   Förderkennzeichen 02 E 8492/3 u. 02 E 8462/9             Report (Abstract)




Rutter, E. H.                           1976 The kinetics of rock deformation by pressure solution                                                  Phil. Trans. Royal Soc. London A 283 (1976), pp.203-219 Journal Article

Fuenkajorn, K.;                                                                                                                                     Proc. 1st. North American Rock Mechanics Symp.,
Serata, S.                              1994 Dilation-induced permeability increase around caverns in salt                                          Austin, 01.-03.06.94, pp.649-656                         Paper




Lee, R.;                                                                                                                                            Proc. 2nd. North American Rock Mechanics Symp.,
De Souza, E.                            1996 The effect of brine dissolution on the strength behaviour of evaporites                                Montréal, 19.-21.06.96, Vol. 1, pp.69-76                 Paper (Abstract)


Munson, D. E.;                               Brine release based on structural calculations of damage around an excavation at the Waste Isolation   Proc. 2nd. North American Rock Mechanics Symp.,
Jensen, A. L. et al.                    1996 Pilot Plant (WIPP)                                                                                     Montréal, 19.-21.06.96, Vol. 2, pp.1495-1500             Paper




Fokker, P. A.;
Kenter, C. J. et al.                    1993 The effect of fluid pressures on the mechanical stability of (rock) salt                               Proc. 7th. Symp. on Salt, Vol. 1, pp.75-82               Paper




Van Sambeek, L. L.                      1993 Evaluating cavern tests and surface subsidence using simple numerical models                           Proc. 7th. Symp. on Salt, Vol. 1, pp.433-439             Paper




Van Sambeek, L. L.                      1992 Dilatancy of rock salt in laboratory tests                                                             SMRI Fall Meeting, Houston, 18.-21.10.92                 Paper




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Kublanov, A.                 1995 Experiences in using hydrofracturing at the holes of Novo-Moscowsk brine field operations                SMRI Fall Meeting, San Antonio, 22.-25.10.95     Paper




Anthony, T. R.;
Cline, H. E.                 1974 Thermomigration of liquid droplets in salt                                                               Proc. 4th. Symp. on Salt, Vol. 1, pp.313-320     Paper




Rummel, F.;
Benke, K. et al.             1996 Hydraulic fracturing stress measurements in the Krummhörn gas storage field, northwestern Germany        SMRI Spring Meeting, Houston, 14.-17.04.96       Paper




Tomastik, B. E.              1993 Investigation of active and abandoned class III salt solution mining projects in Ohio                    SMRI Spring Meeting, Syracuse, 25.-27.04.93      Paper




                                  Geochemische Prozesse in marinen Salzablagerungen: Bedeutung u. Konsequenzen f. d.
                                  Endlagerung..
                                  [Geochemical processes in marine salt deposits: their significance and their implications in connection
Herrmann, A. G.              1980 with disposal of radioactive waste within salt domes]                                                   Z. dt. geol. Ges. 131 (1980), pp.433-459          Journal Article   german




Nelson, R. A.;                    Review of hydraulic fracturing tests in salt, southeastern Utah, compared to other recent salt testing
O'Rourke, J. E.              1986 experience                                                                                               SMRI Spring Meeting, Baton Rouge, 20.-22.04.86   Paper




Thoms, R. L.; Gehle, R. M.   1986 Hydraulic fracturing tests in a Gulf Coast salt dome                                                     SMRI Spring Meeting, Baton Rouge, 21.-22.04.86   Paper




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Allison, H. G.;
Ford, E. C.                1988 The first plug is the key to a good plug and abandonment or liner job                                   SMRI Spring Meeting, Mobile, 25.04.88         Paper


Aufricht, W. R.;
Howard, K. C.              1961 Salt characteristics as they affect storage of hydrocarbons                                             J. Petrol. Technol. (1961) 8,. pp.733-738     Journal Article




                                Zur Frage der Porosität und Permeabilität von Salzgesteinen
Hofrichter, E.             1976 [Remarks on the porosity and permeability of salt rocks]                                                Erdöl-Erdgas-Zs. 92 (1976) 3, pp.77-80        Journal Article   german




Hunsche, U.;                    Das Kriechverhalten von Steinsalz
Schulze, O.                1994 [Creep of rock salt]                                                                                    Kali u. Steinsalz 11 (1994) 8/9, pp.238-255   Journal Article   german
Jewentow, J. S.;                Über die Erdöldurchlässigkeit fossiler Salze. Abgehandelt am Beispiel der Kaspisenke
Mileschina, A. G. et al.   1973 [On the relative permeability to oil of fossil salts. Using the Caspi basin as an example]              Zs. f. angew. Geol. 10 (1973) 2, pp.67-71     Journal Article   german

Piper, T. B.               1980 Hydraulic fracturing applied to solution mining                                                         SMRI                                          Report




Roedder, E.                1984 The fluids in salt                                                                                      Am. Min. 69 (1984), pp.413-439                Journal Article




Rokahr, R. B.;                  Development of a new criterion for the determination of the maximum permissible internal pressure for
Staudtmeister, K. et al.   1994 gas storage caverns in rock salt                                                                        SMRI Spring Meetin, Houston, 24.-27.04.94     Paper
                                Beitrag zur Porosität von Salzgesteinen
Tollert, H.                1964 [Porosity of salt rocks]                                                                                Kali u. Steinsalz 4 (1964) 2, pp.55-60        Journal Article   german




Le Guen, C.;
Deveughele, M. et al.      1993 Gas permeability changes in rock salt subjected to thermo-mechanical stresses                           Quart. J. Eng. Geol. 26 (1993), pp.327-334    Journal Article




Saulnier, G. J.;
Domski, P. S. et al.       1990 WIPP Salado hydrology program data report #1                                                            Albuquerque : Sandia Nat. Lab., SAND90-7000   Report

Wieczorek, P.;
Rothfuchs, T.              1986 In situ permeability measurements                                                                       in: EUR 10827 EN/I, pp.169-180                Paper




                                Plasticité et endommagement des roches ductiles - Application au sel gemme -
Thorel, L.                 1994 [Plasticity and damage of ductile rocks - application of rock salt]                                     Paris : Ècole Nat. Ponts Chaussées            Thesis            French




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Stavrogin, A. N.;
Georgievskii, V. S. et al.   1975 Effect of atmospheric moisture on creep in salt                                                         Soviet Min. Sci.11 (1975) 1, pp.65-67   Journal Article




Rokahr, R. B.;                    Development of a new criterion for the determination of the maximum permissible internal pressure for
Staudtmeister, K. et al.     1997 gas storage caverns in rock salt. Final report                                                          SMRI Research Project Report No. 1-94   SMRI Research Report




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Abstract

Mechanical properties of the rock mass surrounding an underground salt cavern can be measured through different tests performed in brine filled caverns. Dynamic and static tests are discussed and a nine years long static test is fully described.
Additional results confirm that during most of the consolidation of polycrystalline salt in brine, the previously proposed rate expression applies. The final consolidation, however, proceeds at a lower rate than predicted. The presence of clay hastens the consolidation process but
observed relationship between permeability and void fraction. Studies of the migration of brine within polycrystalline salt specimens under stress indicate that the principal effect is the exclusion of brine as a result of consolidation, a process that evidently can proceed to comple
gradient could be identified. A previously reported linear increase with time of the reciprocal permeability of salt-crystal interfaces to brine was confirmed, though the rate of increase appears more nearly proportional to the product of dDP rather than dDP² (d is the uniaxial stres
hydraulic pressure drop). The new results suggest that a limiting permeability may be reached. A model for the permeability of salt-crystal interfaces to brine is developed that is reasonably consistent with the present results and may be used to predict the permeability of bedde
needed, however, to choose between two limiting forms of the model.
Pressure-pulse tests have been performed in bedded evaporites of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) site to evaluate the hydraulic properties controlling brine flow through the Salado. Hydraulic conductivities ranging from about 10-14 to 10-11 m/s
m²) have been interpreted from nine tests conducted on five stratigraphic intervals within eleven meters of the WIPP underground excavations. Tests of a pure halite layer showed no measurable permeability. Pore pressures in the stratigraphic intervals range from about 0.5 to
(Marker Bed 139) appears to be one or more orders of magnitude more permeable than the surrounding halite. Hydraulic conductivities appear to increase, and pore pressures decrease, with increasing proximity to the excavations. These effects are particularly evident within tw
Two tests indicated the presence of apparent zero-flow boundaries about two to three meters from the boreholes. The other tests revealed no apparent boundaries within the radii of influence of the tests, which were calculated to range from about four to thirty-five meters from th
to determine 9 brine flow through evaporites results from Darcy-like flow driven by pressure gradients within naturally interconnected porosity or from shear deformation around excavations connecting previously isolated pores, thereby providing pathways for fluids at or near lith
In order to check the validity of the nitrogen-leak MIT, a gas-brine interface was lowered to half-height of a cavern well in order to minimize the risk of (real) gas leak.
The cavern, which had been leached out 14 years ago, has stabilized; creep, percolation or thermal effects can be considered negligible. Mock leaks were then provoked by injecting or withdrawing known quantities of nitrogen or brine through the well-head. The test gives clea
effect; measured and calculated values of the gas-brine interface displacement and leaks were found to be in good agreement.

Solution-mined caverns will be one day sealed and abandonned. Due to an increasing concern in environmental and safety issues, the long term behavior of brine bubble initially enclosed in the cavern has been analyzed by several authors, who lay emphasis on the fracturation
build up in the cavern caused by brine heating and cavern creep. In this paper we suggest to take into account the rock salt permeability : even if small, it allows some pressure release and leads to a final equilibrium pressure which is substantially lower, in many cases, than the
We discuss several aspects of the so-called MIT test which is performed by lowering a nitrogen/brine interface in the annular space of a salt cavern hole.
1.In case of a gas leak, the leak rate is underestimated by a factor comprised between 1 and 2 when multiplying the annular cross section by the interface rise rate.
2.The interface level, as measured by a logging equipment, can be checked by:
i.Comparing the brine and gas pressures as measured at the well head.
ii.Measuring the cavern compressibility and brine pre-pressure.
iii.Measuring the nitrogen injected mass.
3.Several factors, like thermal expansion, steady state and transient creep, brine percolation can modify the interface rate even in the case of absence of leak. The effect of some of those factors can be precisely estimated.
4.A thoroughful examination of brine and gas pressure at ground level allow for estimating the gas leak.

Three original in situ tests performed on salt caverns are described and discussed. The first is the measurement of the natural vibrations of the brine mass contained in the cavern and tubing. It is proved that their period is of the order of one minute and is related only to the cav
cavern volume is a very simple procedure. The second test consists of measuring the dips induced at ground level by a sudden pressure variation in a deep salt cavern. The average elastic properties of the ground at a very large scale can be deduced from these measurement
resolution tiltmeter.
The last test is the measurement of the volume rate of brine naturally expelled from a salt cavern. The interpretation is difficult, for many phenomena play a role in the expulsion of brine. Slowly-varying phenomena are brine heating, cavern creep and brine percolation. These thr
relative importance is variable during the whole test, which lasted nine years. Atmospheric pressure and temperature at ground level vary widely even during one day. When these phenomena are taken into account, the effects of the daily earth tides, in spite of being extremely
At the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico, the Disturbed Rock Zone (DRZ, the zone of rock in which the -mechanical and hydrologic properties have changed in response to excavation) has been characterized with visual observations, geophysical m
The visual observations, geophysics, and gas-flow tests have defined a DRZ at the WIPP mending laterally throughout the excavation and varying in depth from 1 to 5 m. Desaturation and microfracturing has occurred to some degree within the zone. The dilation that results fro
provides a component of the observed closure.
After they have been washed out, cavities (4) in rock salt contain a large quantity of brine (8) at a temperature which is lower than the temperature of the surrounding formation (2). This means that the cavity cannot be sealed quickly because the brine will expand progressively
invention serves to shorten the time period between the end of working the cavity for salt and being able to abandon the cavity finally from about 30 years to about 2 years. The method consists in injecting quantities of a mixture (12) into the cavity (4), the mixture being of greate
capable of setting, with equivalent quantities of brine (8) being returned to the surface, and then in keeping the cavity (4) open after it has been completely filled with mixture (12) for as long as it takes the rock salt (2) to creep and fill up the shrinkage voids which appear during
the cavity (4) can be sealed. To do this, it is advantageous to make use of waste material for constituting the mixture (12).
Data from the Waste Isolation Pilot Plant (WIPP) site in southeastern New Mexico suggest an alternative hypothesis to the widely held view that salt in a geologic environment below the water table is "dry" and impermeable. The alternative is that the salt section, which for the m
porosity, is saturated with brine. The implication of this hypothesis is that a repository in salt will fill with brine once the ventilation of the facility ceases to remove moisture. The rate of inflow to the facility will depend on the permeability of the salt. Data from the WIPP facility sug
of »10 nanodarcies (10-12 cm/s). Given such a low permeability, the rate of brine inflow to an underground facility will be quite low, of the order 0.01 L/day/m of tunnel.
A method for testing formations of very low permeability is presented. The method is based on an analytical solution that describes the decay of a head change caused by pressurizing the volume of water stored in a shut-in well. Type curves prepared from this solution are matc
the hydraulic properties of the formation tested. The test is similar to the conventional slug test; however, its much shorter duration makes the testing of extremely tight formations feasible.
In situ rock stress measurements by small-scale hydraulic fracturing were performed in two salt beds in the Texas Panhandle, approximately 60km (36 miles) south of Amarillo, Texas. Data analysis indicates that small-scale hydraulic fracturing is applicable for determining the m
stress and the direction of the maximum stress in salt. However, when hydraulic fracturing equations based on elasticity are applied to salt (a non-elastic medium), anomalously high in situ maximum stress and tensile strength values are calculated. Due to the non-elastic proper
the derived maximum stress nor the tensile strength values are considered valid using the elastic hydraulic fracturing stress equations.
Magnesium and potassium salts are being solution-mined from carnallite/bischofite layers in the north-east of The Netherlands, near Veendam. It is planned that, at the end of the mining process, the brine-filled cavities will be abandoned.
The paper presents some rock mechanical considerations with respect to cavity behaviour after abandonment, assuming perfect cavity sealing. A finite element analysis of the cavity response after shut-in, and the design requirements for a suitable sealing plug for the borehole
The finite element calculations indicate a rise in brine pressure after shut-in, followed by a gradual pressure increase towards an asymptotic value. This change in pressure is accompanied by adjustments in the cavity roof, wall and floor stresses.
Different sealing principles and plug designs are considered. Cavity response after abandonment, long-term reliability, and general compatibility with in-situ conditions are the major criteria in the selection of a suitable sealing plug material.
A borehole closure protocol for a Gulf Coast site near Orangefield, Texas was developed by Du Pont. These procedures were based largely upon recommendations provided by EPA Region 6 and created a borehole closure test to demonstrate that, under a worst case scenario
naturally. The borehole closure test successfully demonstrated natural sealing. Within one week of setting the screen, tubing and pressure transducers in the borehole, testing confirmed the absence of upward movement of fluid from the test sand. The documentation for the ab
1) Schlumberger Water Flow Log* and 2) the absence of pressure response on the upper transducer located outside the tubing and inside the casing. Testing was conducted in accordance using specified procedures, with pressure testing conducted at even higher pressures to
The borehole closure test provides a sigfnificant additional margin of confidence that there will be no migration of hazardous constituents from the injection zone for as long as the waste remains hazardous.
Laboratory experiments of hydraulic fracturing in salt have shown that the breakdown pressure does not vary significantly with the differences between the maximum and minimum stresses normal to the borehole axis. The presence of a non-hydrostatic stress in salt may be dete
hydraulic fracture alone. A series of laboratory experiments were performed to determine the influence of deviatoric in situ stress on the form and orientation of hydraulic fractures in salt.
The hydraulic-fracturing tests were run on prismatic blocks in a polyaxial loading frame over a range of stress ratios from 1 (hydrostatic) to 1.5. The fracturing oil contained a fluorescent dye that marked the fracture traces for mapping after the samples were split.
The results indicate that the form of the hydraulic fracture reflects whether or not the stresses are nearly hydrostatic. For large stress ratios (> 1.5), the fractures are straight and strongly oriented. For stress ratios near one, the fractures are poorly oriented and exhibit significant
hydrostatic conditions can be determined from the form of the hydraulic fracture alone, regardless of ambiguities in the interpretation of pressure-time records from the fracturing experiment.




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Hydraulic fracturing tests were performed at about 900 meters (2950ft) deep in a bedded salt formation at ETREZ, eastern France. These tests comprised a "Field Test N°2 with gas" that followed an initial field test, using brine as the test fluid, which was performed in the same
The principal objectives were to determine hydrofrac gradients at different pressurization rates, to compare hydrofrac gradients values obtained with liquid and gas, and to study in such in-field conditions, self-healing effects and percolation of fluids in the salt massif. These are
defining maximum operating pressures in salt formations.
With nitrogen as the test fluid, the hydrofrac gradient with slow pressurization (long-term test over a one-year period) was 0.237 bar/m (1.05 psi/ft). A value of 0.236 bar/m (1.04 psi/ft) was obtained with relatively, fast pressurization (short-term test over a one-day period). With b
bar/m (1.06 psi/ft) and 0.256 bar/m (1.13 psi/ft) for the long and short-term tests respectively. The salt massif seems more resistant to hydrofracture (higher frac gradient) when only one phase (brine) is present in the crystal interstices.
Testing in Well EZ58 began in 1989 and ended in 1994. For each test fluid, the short-term test was performed some time after the end of the long-term test. It was concluded that under field conditions, recrystalization processes can heal fractured salt rapidly, in about one mont
that this self-healing process entirely, restores the mechanical strength of the salt massif.

In this tightness/fracturing test at brine, the pressure in the free space was gradually raised in steps of 0.1 MPa. The pressure reached was held constant for a period of 1 month by precisely controlled injection of fluid. The results presented here were obtained by applying Darc
the fluid injections
It is inevitable that sealing and abandonment will someday occur in a U.S. Strategic Petroleum Reserve (SPR) cavern or caverns. To gain insight into the long-term behavior of a typical SPR cavern following sealing and abandonment, a suite of finite element analyses were perf
quickly and to what extent a cavern pressurizes after it is plugged. The analyses examine the stability of the cavern as it changes shape due to the increased pressures generated after plugging. Internal fluid pressures in a brine filled cavern eventually exceed lithostatic pressur
resulting in enlargement and stress reduction. The buildup of fluid pressure after plugging is largely determined by salt creep, salt dissolution, and geothermal heating of brine. Volumetric closure due to creep increases brine pressure. Salt dissolution and geothermal heating oc
cooler than the surrounding salt at the time of plugging. The individual and coupled effects of creep, dissolution, and geothermal heating are modeled. The analyses suggest that the predicted rate and magnitude of fluid pressurization in SPR caverns is not high enough to resul
cavern pressure can be substantially mitigated by delaying plugging until the brine has come closer to thermal equilibrium.
Granular salt can be used to construct high performance permanent in boreholes which penetrate rock salt formations. These seals are described as seal components of the host rock, the seal material, and the seal rock interface. The performance of these seal systems is defin
between these seal system components through time. The interactions are largely driven by the creep of the host formation applying boundary stress on the seal forcing consolidation of the granular salt. The permeability of well constructed granular salt seal systems is expecte
permeability (<10-21 m² (10-9 Darcy)) with time. The immediate permeability of these seals is dependent on the emplaced density. Laboratory test results suggest that careful emplacement techniques could result in immediate seal system permeability on the order of 10-16 m² t
The visco-plastic behavior of the host rock coupled with the granular salts ability to 'heal' or consolidate make granular salt an ideal sealing material for boreholes whose permanent scaling is required.

The intrusion of water or brine into a final repository for radioactive waste in salt rock is regarded as the greatest hypothetical accident scenario.
The intrusion of water or brine into a final repository for radioactive waste in salt rock is regarded as the greatest hypothetical accident scenario. The most crucial aspect is the prevention of dispersal of the dissolved radionuclides into the biosphere. Special plugs or seals in add
rock and caprock play a significant role in preventing the escape of nuclides through cavities.
The decision to flood the abandoned potash mine at Hope, north of Hannover, was made in 1982. In addition to geochemical, geophysical and aeomechanical investigations this provided the first opportunity for testing the tightness of a bulkhead in situ at a pressure of 6 MPa at
Salts are mined for both storage and extraction purposes, either via dry or solution mining techniques. For operational, environmental and geological purposes, it is important to understand and predict the in situ behaviour of salt, in particular the creep and strength characteristi
A micro-mechanically based explanation and quantification of primary (strainhardening) creep in rocksalt have not yet been reported. Creep models for primary creep are still mainly based on curve fitting. At relatively low temperatures (0-200 C°), as encountered near all excava
important, certainly at laboratory time scales.
Since understanding of the mechanism may be important in extrapolating relatively short term laboratory tests to long term creep in situ, an attempt is made in this thesis to explain (and simulate) both primary and secondary (steady state) creep via a micro-mechanical approach
governed by dislocation motion, which becomes increasingly hindered with strain by crystal lattice defects, resulting in strain hardening. The defects in turn are assumed to be dislocation dipoles (two mutually trapped dislocations of opposite sign). Recovery in this model is rela
generation of vacancies and interstitials by the disintegration of dipoles consisting of very near dislocations. These vacancies and interstitials in turn precipitate on other (more rigid) dipoles, allowing them to annihilate by climb. This model describes the observed measurement
transition zones after changing a strain rate. Unfortunately this model does not result in a simple constitutive equation, although possible in theory. Simpler, but for general practice usually sufficiently accurate, curve-fitting laws have been implemented in the DIANA Finite Eleme
salt creep behaviour.
Rocksalt at greater depth is usually impermeable, thus forming a good seal against fluid penetration. A combination of high deviatoric and low confining stresses leads to dilation and even failure during deformation. Tensile stresses can result in micro- or macro-fracturing of the
sealing capacity of salt. Contrary to common opinion so far, it is shown here that fluid pressures (as present in, for instance, caverns or aquifers) do not increase the sait's bearing capacity. Hence, salt needs to be treated like a Terzaghi material, subtracting fluid pressures from
dilation or fracture criteria.

The constitutive behaviour of rocksalt is explained from micro mechanical concepts. Rocksalt plasticity (or primary creep) can be well explained by a dislocation glide mechanism, where gliding becomes increasingly hindered by dislocations (in fact dislocation pairs or dipoles), d
are both the main source for hardening, as well as the main source for time dependent behaviour. From such a description a deformation model can be derived that relates strain rates to stresses, strains and the temperature. The resulting creep curve bears great similarity with
Schreiner deformation law. However, different from these curve fitting laws, primary creep here is based on proper micro-mechanical considerations and moreover can cope with the transient effects as occurring when load or strain rate increments are suddenly changed.

The main criteria for the construction of storages or for the use of existing underground cavities for storage is the tightness of the rock surrounding the cavity. The maximum working pressures for the cavity must therefore be selected to ensure that the host rock will not fracture,
The investigations described here focus on the rock surrounding the salt cavity.
This paper describes the process, criteria, and considerations for design of borehole seals in rock, with a main emphasis on the hydraulic and mechanical performance of the cementitious and bentonitic seals. It is recommended that design and material selection for borehole se
sealing effectiveness should be made on the entire seal system, i.e. seal, seal-rock interface, and the surrounding rock.

The functional relationship between various definitions of effective stress, i.e., conventional, Biot-Willis-Nur-Byerlee, and theory of interacting continua (Tinc), is explored both theoretically and experimentally. Stress-strain data on dry and saturated Weber sandstone demonstra
law grossly overestimates the pore pressure effect, whereas Biot-Willis-Nur-Byerlee and Tinc laws somewhat underestimate this effect. Failure is examined from a microscopic point of view. It is shown that Tinc-type effective stress laws cannot account for the effect of pore pres
Failure is one aspect of material response in which the conventional effective stress law is useful. In summary, it appears necessary to have two effective stress laws, i.e., one to describe the stress-strain response and a second to delineate the failure surface.

The matching curves are presented on figures 20 and 21.
It was made clear during the simulation progress that it was not possible to correctly match the injected volumes over the whole test, taking into account the assumptions about pressures initialization and salt petrophysical characteristics invariance in the vicinity of the well durin
Indeed, if the permeability is chosen so as to adjust the brine quantities on the first steps (1.6 to 2 gradient), the volume required for the next steps will be much too high. If, on the contrary, the matching is made on the last steps the computed values will be too small for the first
In the first case, we have to assume that the characteristics of the open hole sail change during the test : the permeability in the vicinity of the well or, at least the productivity index would decrease with time.
In the second case, it is possible to think that the uncertainty on the initial pressures condition prevents to correctly simulate the flow rate at the beginning of the test, while its influence becomes less important on the last steps.
This last assumption was eventually retained for the interpretation.
The matching was mainly performed on the permeability as it is less sensitive to the porosity. It is possible, for instance, to obtain similar computed flow rates with the following values :
k=6 x 10-5 mD =1 % (mean value)
k=5.5 x 10-5 mD =2 % (mean value)
k=6.5 x 10-5 mD =0.5 % (mean value)

The influence of other parameters was also examined : if rock or fluid compressibility is increased, the variation of the injected volumes from one gradient to another one stays similar, but it is again necessary to decrease the permeability to find the same values.
Eventually, the simulations were performed with a permeability of 6 x 10-5 mD and a porosity of 1 %.




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A method is described for measuring the permeability of rock salt. Different specimens of salt were studied, and the technique was checked by use of a solid crystal of sodium chloride. Both reactive and nonreactive fluids were used in collecting permeability data. Permeability te
dome and bedded formations. The dome salt was found to have a very low permeability, and the bedded salt was found in general to be impermeable. Where there was some measurable permeability under the conditions of the test, it was found that the permeating flow occurre
salt and not through the crystals themselves. These fractures were apparently caused by the relaxation of stress which occurs when underground samples are removed from a compressed formation. The dome salt was found to have more fractures than the bedded salt, owing p
Such surface fractures, found in both types of salt, will be localized in the vicinity of a mine and consequently will not extend throughout a formation.
This paper examines one of the major uncertainties in the application of laboratory test results to the design of solution-mined storage cavities in rocksalt. The properties of salt are such that water will, when present, have significant effects on mechanical behaviour, including en
increased capacity for creep deformation and possible volume changes associated with the hydration of secondary minerals. Although these effects are widely recognized, surprisingly few observations have been recorded and the available data, discussed here, can only be as
evidence is, however, sufficiently conclusive to indicate that, unless special measures are taken to reproduce the in situ condition of the salt in the laboratory, the experimental results will be grossly incorrect. The uncertainty lies in the selection of appropriate laboratory test con
that, for cavity closure prediction, salt specimens should be thoroughly dried and tested under conditions devoid of moisture.
Two 100 mm diameter by 200 mm long cylinders of Avery Island (A.I.) rocksalt have been subjected to a constant strain rate 10-9 s-1 at 15 MPa confining pressure and 50 and 100°C. The experimental conditions have been virtually constant over a period of about 3.5 years dur
homogeneously by about 11%. The specimen deformed at 100°C (Test 47) reached a steady-state stress of 4.7 MPa at 2% strain whereas that at 50°C (Test 46), still slightly work-hardening, reached a quasi steady-state stress level of 12.6 MPa. Microstructural analysis reveals
dominated deformation at 50°C whereas, at 100°C, subgrain development is excellent indicating extensive dislocation climb.
These data points from Tests 46 and 47 were combined with nine earlier constant strain rate steady-state test results to provide, by nonlinear least squares, the relation

e8 = 6.5 x 10-5 exp (-69.7/RT 10-3)s5.9

When added to 27 A.I. constant stress test data points of RE/SPEC Inc., ten of the low stress, low strain rate tests at 100 and 200°C are very well fit by e a s3.4 whereas the remaining high strain rate, high stress quasi steady-state data are well fit by e a s5.2. This change in be
change in dominant, rate-limiting, mechanism bears importantly on inferences concerning rates of natural salt deformation. At comparable temperature and stress, the e a s3.4 relation predicts strain rates two orders of magnitude higher than does the e a s5.2 equation; the latte
This paper describes preliminary interpretation of in-situ pressure and flow measurements of the Salado Formation at the Waste Isolation Pilot Plant (WIPP). The WIPP facility is located 660 m underground in the Salado, a bedded salt deposit. Shut-in pressure tests were condu
mining of a circular drift in order to evaluate excavation effects on pore pressure, permeability, and host rock heterogeneity. Borehole deformation was measured during these tests and used to correct for changes in the test region volume due to salt creep effects.
Preliminary pre-excavation results indicate that the flow properties of this layered host rock are heterogeneous. Resulting pore pressures range from 1 to 14 MPa and permeabilities range from below measurable to about 1 nanodarcy. Normalized borehole diameter change rate
microstrains/day.
Shut-in pressures and borehole diameters in all test boreholes were affected by the excavation of Room Q coincident with the advances of the boring machine. Preliminary results from post-excavation test results show decreased pore pressures compared to pre-excavation valu
The solution in accordance with the invention prevents for the most part the transfer into the cavern roof of substantially higher rock pressures from the lower cavern section and hence substantially reduces the risk of fracturing. The invention enables safe abandonment of salt c
hazardous materials and waste products.
The connection between the rheological behaviour of the mineral halite (NaCl) in the presence of very small quantities of free water and radioactive waste disposal may at first seem obscure. There is a strong link, however, some aspects of which are described by Urai et al. (1)
previous work (2, 3), these authors go some way towards elucidating the marked effects on halite rheology of the very small quantities of brine inherent in a polycrystalline salt mass. The investigations have important implications for the determination of long-term stability in any
considered as a repository of radioactive waste or for material storage. Their findings are also of importance in the wider field of salt tectonics.

Operational experience has shown that a fluid filled cavity in rock salt is tight at normal operating pressures which are below the ambient lithostatic salt stress. However, little is known about the tightness at pressures above lithostatic. It was shown in an experimental set up that
roof under these conditions. The process is largely governed by a threshold pressure, being the ambient litho-static stress. Below this threshold flow is negligible; above the threshold pressure the fluid is opening up intercrystalline boundaries in the rock salt. Once a flowpath ha
driven by the excess pressure above lithostatic only and not to be affected by the pressure drop from lithostatic to hydrostatic. The permeability decreases about proportional to consolidation pressure and consolidation time of the salt sample on a log-log scale.
The interpretation of in-situ-hydrofrac results in salt rock is fraught with particular difficulties, if there is a marked deviation between the measured critical pressure values and the theoretical results expected. Here the performance of tests along with rock and rock massspecific p
significance. Some laboratory experiments are presented, which indicate the influence of various test parameters on the level of the frac pressure measured. Therefore thickwalled cylindrical specimes of rocksalt, lithostatically loaded in a pressure chamber (autoclave) were inje
different test conditions to initiate hydraulic fractures.
Concern for leakage of reactor fuel waste materials from underground salt cavities has prompted questions regarding the permeability of rock salt materials. To provide information on this question, the flow rate of kerosene through rock salt specimens was studied for a range of
stresses. Kerosene was used as the fluid because of a similarity to radioactive waste materials and its nonrusting properties when In contact with steel. Expressions for the permeability of the rock salt were developed In terms of the stress conditions and void ratios of the rock s
A high pressure triaxial cell was designed and constructed for permeability tests at various stress states. The cell permitted application of axial loads separate from lateral pressures. Independent hydraulic systems maintained axial and lateral pressures to about ± 5 psi of select
axially through the sample under a head differential of 125 psi.
Rock salt from an underground formation In Louisiana was cut into cylindrical samples 3 inches high by 3 inches in diameter. Strain gages attached to the sides of the sample provided information on tangential and axial strain. Overall axial deformation, obtained by means of a d
cell, provided a check on strain gage values. Kerosene flow through the sample was recorded at given time Intervals.
The experiment date provided the basis for developing empirical expressions for the rock salt permeability in terms of the mean normal stresses and octahedral shear stresses. Strain measurements permitted incorporating changes in void ratio into the permeability expressions.
salt appears to obey approximately the same laws as developed for flow of water through soils. Laboratory permeabilities for the rock salt varied from 0.0036 to 40.6752 milli-darcy for various stress states. Very low permeabilities indicate that leakage of radioactive waste materi
The need for storage caverns for oil and gas, and repositories for toxic chemical waste is increasing world-wide. Rock salt formations are particularly suitable for the construction of cavities for such purposes. Owing to its favourable geomechanical properties, rock salt remains s
support, and it can be shown that the geological barrier of the host rock remains intact for a remarkably long time.
Safety analysis must be made for each proposed site based on site-specific data. The methods of doing this are well known and related technical recommendations exist in Germany. These recommendations apply to the planning, construction, opera. tion and post-operational m
the underground disposal of hazardous wastes. In particular, geotechnical site-specific safety verification, as required by the govemment's technical regulations on wastes (TA-Abfall) under the section "Underground Disposal", is required. This safety verification must cover the e
the cavem and the surrounding rocks. For this purpose geomechanical models have to be developed. The steps which must be taken when carrying out geological engineering site explorations and when determining geotechnical parameters are discussed. In addition, recomme
construction of underground repositories.
For liquid-filled caverns, long-term sealing from the biosphere is of particular interest. In this instance it must be shown that the natural increase in pressure in the closed cavity due to long-term convergence does not exceed the fracture pressure. A special field test (scale 1:1) h
A number of soundly based modern salt mechanical methods are available for the rock mechanical elaboration of stability aspects in rock salt caverns. These are: material laws and material parameters, failure criteria, and calculation techniques based on the finite element meth
discussion of these tools, the special stability problems occurring when sealing liquid-filled repository caverns will be analysed. In particular, the pressure increase in such caverns will be calculated using models, and these will be used to derive conclusions on the frac risk. The
conventional hydraulic frac tests in boreholes cannot be directly extrapolated, but require prior comprehensive computer analysis.
Permanent disposal of wastes in salt caverns must address the effects of salt closure plugging of the disposal well. Caverns with liquid components to the waste, or significant liquid remaining from the leaching / brine removal process, have the capability to create sufficient pres
the cavern integrity threatened. Our understanding of the salt creep and thermal processes associated with cavern waste disposal and current state of the art modeling capabilities are sufficient reasonably accurate predictions of sealed cavern pressures. Strategic Petroleum Re
pressures following plugging and abandonment analyzed. Results of FEM analysis are shown that detail the time frame and, magnitude of the pressurization problem. Waste disposal would nominally be done in similar geometries, and at similar depths. The final internal cavern
dependent on initial temperatures and salinity of the fluid. For caverns of SPR height and salt dome geometries, final pressures are not predicted to place the salt in tension and potentially create salt cracking or fractures. Limited experimental data available from foreign tests h
maintaining integrity under such conditions. Until further controlled experiments with real caverns or wells can be completed, the long-term integrity of sealed salt caverns with significant liquid components will remain uncertain. Use of caverns for oil and gas waste disposal mus




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The first test series to determine permeability carried out in August 1989 took place prior to drifting the south barrier roadway in unfractured evaporite. The permeabilities determined were generally in the range k < 1.0E-21 m2. The exception was borehole UP5 which had a high
borehole, which was divided into two measurement intervals, there was communication above the salt between the measured zones, which was confirmed by marking with neon, so that both intervals were investigated together in the following test. The second test series carried
carried out prior to drifting the south barrier roadway. In the interval between these two test series, boreholes UP3 and UP4 were no longer usable because of leaking packers. The tests carried out during this test phase largely confirmed the results of the first test series. Howev
had risen. In the case of borehole UP7 which was still very tight in the first test series with less than 1.0E-21 m2, the permeability had increased to around 7.6E-18 m2 to 6.0E-17 m2 during the second test series.
During the drifting of the south barrier roadway (third test series), boreholes UP2 and UP6 which terminate a distance of 2.5 m and 5.6 m respectively above the roof of this roadway were tested. No effect was noticed during drifting.
Only in the fourth test series carried out after drifting did borehole UP2 show a slight increase in permeability from less than 1.0E-21 m2 to 3.0E-21 m2. No permeability increase was established in borehole UP6 after evaluation with Interpret/2, which was attributable to the fact
permeability limit of 1.0E-21 m2, which is above the values for borehole UP6. However, the pressure data pointed to a slight increase in permeability. Interestingly, borehole UP8 which had the largest separation from the roof (12.1 m) had a permeability increase of 2.0E-21 m2
UP7 - which previously had higher permeabilities - also revealed an increase in permeability. A clear increase in permeability in borehole UP5 which was closest to the roof (1.6 m separation) pointed to the development of a fracture zone at the edge of the roadway. The permea
boreholes, namely UP7 (8.0 m) and UP8 (12.1 m), may be attributable to far-reaching stress relocations caused by drifting of the roadway.
Closures and closure rates measured around excavations in the bedded salt formations at the Waste Isolation Pilot Plant (WIPP) were at least three times larger than initial predictions made with a reference creep model for rock salt. Subsequent investigations uncovered a num
including questions about the constitutive behavior of salt in situ (Morgan et al., 1986; Munson & Fouum, 1986; Munson et al., 1989). In addition, controlled laboratory experiments on thick-walled hollow cylinders of salt, subjected to various combinations of axial load, internal p
temperature, were suggested as one expedient and cost-effective means of narrowing the existing uncertainties (Lux & Heusermann, 1985, Van Sambeek, 1986; Wawersik & Morgan, 1987). Two recent tests on thick-walled cylinders of rock salt are discussed in this paper to ex
experiment and to address four concerns: (1) differences between behavior of salt core in the laboratory and behavior of salt masses in situ due to, e. g., hardening and damage during sample extraction, (2) generalization of triaxial measurements to three dimensions requiring c
rules, (3) effects of inhomogencous stress states with gradients as opposed to homogeneous stress fields, and (4) effects of pressure and moisture (Wawersik & Morgan, 1987).
The present evaluations are based on comparisons of measurements on the hollow cylinders with predictions from three different constitutive models for rock salt. The three models are (1) an elastic power-law secondary creep (ESC) model, (2) a revision of the ESC (RESC) mo
This paper investigates by numerical methods the cause(s) of mine seismicity and mine flooding occurring at several potash mines in Saskatchewan, Canada. To assist in the investigation, a finite-element model based on viscoelastic / viscoplastic material behaviour has been u
mining situations it is concluded that hydraulic fracturing of the brittle Dawson Bay formation occurs as a result of changes in the stress-strain regime due to mining and this might be a possible cause of induced seismicity. Hydraulic fracturing of the Dawson Bay and underlying
communication of the aquifer with the top of the mine development openings and rooms and hence a path for flow of pressurized water into the openings.
Hydraulic fracturing of both the Dawson Bay and underlying evaporite layer are demonstrated to be dependent upon pore water pressure in the aquifer, the in situ state of stress prior to mining and the duration of mining.
The multimechanism deformation model for the creep deformation of salt is extended to treat the response of salt to imposed stress drops. Stress drop tests produce a very distinctive behavior where both reversible elastic strain and reversible time dependent strain occur. Thes
compared to the positive transient strains produced by the normal creep workhardening and recovery processes. A simple micromechanical evolutionary process is defined to account for the accumulation of these reversible strains, and their subsequent release with decreases
stress drop tests for various stress drop magnitudes and temperatures are adequately simulated with the model.
The final disposal of hazardous wastes in underground repositories will have an increasing importance in the future. Salt caverns created by solution mining have to be considered as a promising alternative to existing repositories excavated by conventional mining techniques.
As the initial stress in a disposed waste material is lower than the stress in the surrounding rock mass, closure of the cavern is the consequence which, however, is influenced by the back fill material (hazardous waste) in the cavern. The resulting interactions are investigated by
It is shown that sealing of a liquid-filled cavern causes a pressure increase, and that finally the pressure in the cavern roof exceeds the primary rock stress, the amount of the excess pressure depending on the cavern geometry. The resulting divergence is accompanied by tensi
mass, although no tensile stresses occur. Under these circumstances, it has to be proved that a disposed liquid does not spread in the rock mass, and that the long-term tightness of the sealing construction is maintained.
Considering the final disposal of solid hazardous wastes, both loose granulated and in situ hardening materials are analysed. The results of the FE-calculations demonstrate that, from a geomechanical point of view, those materials are favourable which quickly achieve a high s
deformability. The stress-strain-behaviour of a granulated hazardous waste has to be investigated in detail, and has to be described by an adequate material law.
It is important to have quantitative predictions of brine movement in a radioactive waste repository for performance assessment and for seal design evaluations. Experiments to quantify brine transport to boreholes in multi-heater, full scale tests simulating high level waste repos
way in the bedded salt of the Waste Isolation Pilot Plant (WIPP) since April 1985. Water vapor released to the test boreholes has been collected in flowing nitrogen and weighed periodically. Before heating, water was collected during several days from four test boreholes at rat
result highlights the need for an isothermal model for brine movement in the host rock salt. After heating began, the water collection rates rose to a peak. decreased, and then remained nearly constant for several hundred days. Subsequently trends to decreasing rates have bee
water were 4.3 kg at 441 days from each two boreholes in Room A1 (with a 470 W heater in each borehole). and 36 to 38 kg at 600 days from each of the two boreholes in Room B (with a 1500 W heater in each borehole). After the early transients. approximately 8 g day boreho
to 80 g day borehole were collected in Room B. These are much larger brine inflow rates than were observed during heated brine migration tests in the domal salt of the Asse mine in the Federal Republic of Germany. Results from in situ brine transport tests in domal salt are no
salt.
Although the excavations in bedded salt at the Waste Isolation Pilot Plant (WIPP) are, for all practical purposes, dry, small amounts of brine have been observed to weep from exposed surfaces in the repository horizon and seep into drill holes in the underground excavations. A
Evaluation Program (BSEP) at the WIPP, this study has been made to formulate the complex problem of brine and nitrogen flow through deforming salt as completely as possible. The derived equations are coupled where appropriate in order to closely describe the natural phen
paper is to suggest a method by which the formulation might be solved in order to estimate the brine inflow rate into the excavated rooms at the WIPP repository level. The suggested solution method requires the modification and combination of two finite element codes which m
computer memory for data storage.
The exact expressions for the effective stress (sij) and, in particular, pressure (P) that cause elastic strain of material with pore fluids are, assuming only that Hook's law is valid, (sij) = (sij) - aPsij and <P> = Pc - aPp, where a = 1 - (K/Ka), Pc and Pp are confining and pore pressu
of the rock and grain, respectively. The equation for <P> was first suggested by Geertsma (1957) and by Skempton (1960) on empirical grounds. The expression does not depend directly on porosity, but when pores vanish the effective pressure <P> equals the confining pressu
strain of a porous solid with pore pressure can be completely determined from the elastic modulus of the solid without pore pressure, if the effective stress law in the equation for (sij) is used. The exact expression for the effective stress describes quite accurately the measured s
samples at confining and pore pressures to 2.5 kb. The results are not applicable to inelastic processes, such as fracture, or elastic processes other than strain.
It is affirmed that a consistent development of the equivalent channel model for both fluid permeation and electrical conduction in saturated porous media leads to the expression CR²/F where R is the hydraulic radius, F the formation resistivity factor or tortuosity/porosity ratio an
around 0.3 to 0.4. This expression is approximately supported by observations reported on granular media and fairly porous rocks. Confirmation of its applicability to low porosity, microcracked rock is still lacking but it would appear to be consistent with measurements on granite
radius (represented by half the mean crack opening width) decreases as the confining pressure is increased. In any application it is important in estimating R and F to take only the connected porosity into account.




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This report represents a final report on work done on the transport properties of salt during the period 1/1/84 - 30/6/85. The work documented was directed largely at the measurement of creep-induced permeability in salt rock, at determining the permeability persistance/decay c
rock under hydrostatic conditions (wet and dry), and at ion migration/retention experiments on both deformed and undeformed material. The main conclusions drawn are summarised below:-
1)Measurements performed using argon gas have shown that the true (inert liquid) permeability of intact Asse salt rock (Speisesalz) is <= 10-20 m², even at confining pressures of only 2.5 - 5.0 MPa. Natural undisturbed material at depths > 800 m (i.e. confining pressure >= 18
permeabilities of < 1 x 10-21 m².
2)"Crept" salt rock extracted from gallery walls may exhibit permeabilities up to 10-17 m², or higher if badly disturbed. Note, however, that in the case of galleries at the 800m level in the Asse Mine, the region of substantially increased permeability seems to be limited to a depth
3)Gas permeability measurements made on samples deformed experimentally under worst case conditions (high deviatoric stress, low pressure) show increases in permeability from 10-21 m² to ~10-15 m². It is inferred that the maximum likely value for purely creep-induced perm
probably around 5 x 10-16 m².
4)Argon gas permeability tests performed on experimentally deformed (work hardened and dilated) Asse salt with a (worst case) permeability of ~ 10-16 m² have shown that permeability reduction under hydrostatic conditions (presumably by compaction creep) occurs only at eff
MPa. Measured rates of permeability reduction in the range Pe = 8.5 - 13.5 MPa are ~ 4 x 10-23 m² s-1. These rates can not yet be extrapolated reliably to predict long term behaviour but suggest that the time required to reach a natural, non-dilated permeability of 10-21 m² from
order of 1 - 1000 years (at effective pressures Pe = 8.5 - 13.5 MPa). More rapid rates of permeability reduction can be expected when Pe exceeds the maximum deviatoric stress reached during deformation. For lower values of Pe, instantaneous changes in confining pressure s
recoverable, elastic manner. The magnitude of this effect diminishes with increasing Pe.
5)Brine permeability tests performed on similar material (see 4), under hydrostatic conditions, have shown that wet permeability decay rates depend upon effective confining pressure (Pe) and brine flow rate (and/or brine pressure gradient). The flow-rate/pressure-gradient effec
very important. It should be noted, however, that the effect may represent a manifestation of electroviscous drag phenomena. Further work is required here to understand and quantify the observed effects adequately. Nonetheless, at the flow rates and pressure gradients used i
permeability to brine appears to obey a power law of the form k= At -b, where b= ~0.5 at Pe = 8.5 MPa, and b= ~l at Pe = 18.5 MPa. The long term validity of this law is uncertain. Note that at a given permeability and effective confining pressure, wet dilated Asse salt rock under
permeability, during a saturated brine flow-through experiment, than the equivalent dry material. This is presumably due to solution transfer effects.
6)Permeability measurements performed on individual samples using gas (argon) and then brine (under almost identical conditions) are in excellent agreement, at permeabilities of the order of 10-17 m2.
7)Migration/retention experiments on intact Asse Speisesalz placed in contact with brine containing high concentrations of Cs+ , Sr2+ , or Fe3+ (at NTP) have shown that in the absence of a hydraulic head, no detectable ionic migration occurs within laboratory time scales.
8)In similar experiments performed on creep-dilated material, relatively rapid migration of Sr2+ and Cs+ occurs as a result of capillarity-driven migration of brine into voids. Further:-
-In the case of Cs+, no detectable retention effects were observed.
-In contrast, strong retention was observed for Sr2+ . This retention is primarily due to precipitation of insoluble SrSO4 at polyhalite grains, via ion exchange reactions. Similar retention effects can be expected for all contaminant ions having insoluble sulphates.
While the fluid transport properties of rocks are well understood under hydrostatic conditions, little is known regarding these properties in rocks undergoing crystal plastic deformation. However, such data are needed as input in the field of radioactive waste disposal in salt forma
understand deformation, shear zone evolution and associated fluid movement, metamorphism and mineralization in the deep crust and even upper mantle.

The present study is concerned with the development of a fundamental understanding of the influence of crystal plastic deformation on dilatancy and permeability evolution in salt rocks and salt/anhydrite rocks. It is experimentally based and seeks to explain the influence of defo
framework of "percolation theory", currently finding wide application in solid state physics. The results relate directly to the behaviour of salt rock in disposal systems and, viewing salt as an analogue material, provide insight into the effects of plastic deformation on the fluid trans
general.
Chapter 1 introduces the problems to be investigated. Chapter 2 describes the experimental apparatus and methods used and developed during the study.
The work reported in Chapter 3 was principally directed at the influence of crystal plastic deformation on dilatancy and permeability development in natural rocksalt (Asse Speisesalz, Germany) under repository relevant conditions. The intact starting material was found to have a
m²). In deformed material from gallery walls, values up to 10-16 m² were measured. In triaxial deformation experiments performed on intact material at room temperature, minor amounts of dilatancy (< 0.2 vol%) accompanying crystal plastic deformation led to extremely rapid init
suggesting critical behaviour of the type described by percolation theory. Microstructural evidence showed that dilatancy was associated with grain boundary and transgranular microcracks. Additional short-term hydrostatic experiments, performed on dry dilated material, showe
depend on pressure in a manner best explained by an elastic microcrack closure model. Long-term hydrostatic experiments on dilated material, dry and wet, showed permeability to decrease with time. Permeability decay rates were faster in wet material presumably due to crack
Chapter 4 documents triaxial compression experiments designed to determine the influence of plastic deformation on dilatancy and permeability development in fine grained synthetic salt rock, at room temperature, confining pressures (Pc in the range 5 - 20 MPa and strain rate
This paper will describe experimental techniques and review the results of two sets of borehole tests aimed at quantifying the ability of grout plugs to seal boreholes through either anhydrite or halite formations. One set of tests was performed on a grout plug placed in a borehol
performed on horizontal and vertical plugs set in shallow boreholes drilled into the ribs and invert of a mined facility. These tests were performed in order to evaluate the capability to seal boreholes and shafts against incursion of aquifer fluid.
A total of eighteen (18) gas permeability tests were conducted by S-CUBED for Sandia National Laboratories (SNL) as part of SNI Contract No. 58-5831. These tests were conducted at the Waste Isolation Pilot Plant (WIPP) facility horizon in southeastern New Mexico. The obje
to determine:

*The permeability and porosity of the competent salt,*
*The permeability variation with distance from the mined surface, and
*The influence of the interspersed clay and anhydrite seams on the measured permeability values.
Six short duration "order-of-magnitude" permeability tests were performed as Phase II of this project. These tests were used to provide confirmation of the Phase I test results.
Two types of test were performed. In one test the downhole pressure was maintained at an approximate constant value and the resulting flow measured. In the second, the test region was pressurized, then shut-in, and the pressure decay subsequently monitored. The resulting
permeability and porosity values.
The test system and test technique used for the twelve Phase I tests were designed to evaluate formations having permeability to porosity ratios as low as 10-4 darcy. This downhole measurement system consisted of a dual packer assembly which isolated a test interval and ad
test interval pressure, temperature, and flow (as well as the guard interval pressure) were measured. Use of the guard interval was critical to interpreting data obtained in these low permeability formations.
Permeability and porosity values were inferred from the measured data using one-dimensional and two-dimensional axisymmetric solutions to equations describing gas flow through an isotropic porous medium. In those cases, where the analytical/numerical solutions failed to de
additional testing should be performed to evaluate the formation characteristics.
This is a study of the formulation, some basic solutions, and applications of the Biot linearized quasistatic elasticity theory of fluid-infiltrated porous materials. Whereas most previously solved problems are based on idealizing the fluid and solid constituents as separately incomp
constituent compressibility. Previous studies are reviewed and the Biot constitutive equations relating strain and fluid mass content to stress and pore pressure are recast in terms of new material parameters, more directly open to physical interpretation as the Poisson ratio and
undrained deformation. Different formulations of the coupled deformation/diffusion field equations and their analogues in coupled thermoelasticity are discussed, and a new formulation with stress and pore pressure as basic variables is presented that leads, for plane problems,
representation of solutions. The problems solved include those of the suddenly introduced edge dislocation and concentrated line force and of the suddenly pressurized cylindrical and spherical cavity. The dislocation solution is employed to represent that for quasi-static motion
is given, based on fracture mechanics models for fault propagation, of phenomena involving coupled behavior between the rupturing solid and its pore fluid, which could serve to stabilize a fault against rapid spreading. Also, the solution for a pressurized cylindrical cavity leads
The invention is with respect to a process for the permanent sealing of caverns in carnallitite constructed using either hot or cold solution mining and filled with liquid following completion of the solution mining process. According to the invention, after termination of solution min
comprising a highly concentrated MgCL2 solution of at least 0.4 - 0.5 m thickness is injected via the leaching string directly below the cavern roof, whereby the solution is either saturated or supersaturated with components KCl and NaCl and the solution temperature is 5-20 K a
cooling the sealing solution starts to crystallise forming a primary seal at the cavern roof and such that in the event of movement of the cover rock the sealing solution penetrates into possible migration paths forming a secondary seal.




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Phase I: Constitutive Equation of Finite Element Program GEO

outcome of literature studies on theories, laboratory experiments and in situ measurements of salt permeability, as well as formulation of a salt deterioration function and an inelastic volume expansion function.
A large amount of experimental data, including recent results provided by Sandia National Laboratories, has revealed permeabilities of undisturbed in situ salt to be less than 10-22 m². The data also reveal that around an opening, the permeabilities can be as high as 10-18 m².
permeability zone change with time due to the plastic creep and time-dependent fracture propagation of the salt. The change is identified as an outcome of chain reactions of the five basic relations:
1) stress-strain, 2) strain-deterioration, 3) deterioration-volume expansion, 4) confinement-porosity, and 5) porosity-permeability.
A permeability function has been formulated by presenting the five component relations of the chain reactions in order to construct the finite element program of permeability of salt. Various aspects of the relations have been calibrated and tested against laboratory and field me
development. Phase II: Finite Element Model to Predict Permeability Increase around Salt Cavern
Theoretical models for compaction creep of porous aggregates, and for conventional creep of dense aggregates, by grain boundary diffusion controlled pressure solution are examined. In both models, the absolute rate of creep is determined by the phenomenological coefficien
activated term representing effective diffusivity along grain boundaries. With the aim of determining Z(), DH and hence Z* for pressure solution creep in rocksalt, compaction creep experiments have been performed on wet granular salt. Compaction experiments were chosen sin
solution creep is accelerated in this mode. The tests were performed on brine-saturated NaCl powder (grainsize 100-275 mm) at temperatures of 20-90°C and applied stresses of 0.5-2.2 MPa. The mechanical data obtained show excellent agreement with the theoretical equatio
samples exhibited well-developed indentation, truncation and overgrowth microstructures. We infer that compaction did indeed occur by diffusion controlled pressure solution, and best fitting of our data to the theoretical equation yields Z() = (2.79 ± 1.40) x 10-15 m³s-1, DH = 24
values into the theoretical model for conventional creep by pressure solution leads to a preliminary constitutive law for pressure solution in dense salt. Incorporation of this creep law into a deformation map suggests that flow of rocksalt in nature will tend to occur in the transition
This report documents work done on the rheological and dilatant properties of dry and wet salt during the period 1/11/81 - 31/12/83. The report opens with a review of previous evidence and theoretical models for water weakening effects in the long-term creep of salt. The progr
such effects experimentally. Sections 3 and 4 describe the experimental apparatus and techniques used. Section 5 reports detailed characterisation work on the experimental starting material (Speisesalz, Asse, FRG). Section 6 deals with experiments on the rheological/dilatant
results show that even under worst case conditions, creep-induced dilatancy is almost completely suppressed at hydrostatic pressures > 15 MPa. Experiments on the influence of brine are reported in Sections 7 and 8. These show that small amounts of brine (e.g. 0.05 wt% inhe
decrease in the creep strength of salt at low strain rates. This is related to a change in deformation mechanisms from dislocation glide/creep (at normal laboratory rates) to creep involving fluid-assisted recrystallisation and diffusional creep (at low rates). The results imply that g
cannot necessarily be extrapolated to predict long-term behaviour under natural conditions. Final conclusions are summarised in Section 9.
An approach for predicting the development and subsequent healing of the DRZ in rock salt has been developed to support seal design activities. Structural models of rock salt behavior are used to predict (1) dilation (inelastic volume strain) in response to excavation to estimat
changes in response to seal emplacement to estimate DRZ healing. This approach focuses on the mechanical response of the rock salt; permeability changes are not explicitly considered. By limiting the approach to the mechanical response, we focus on the more tractable por
predictions of damage and healing consistent with their underlying mechanisms.
This approach was applied to a shaft seal location at the disposal horizon. The damage zone predicted to develop from excavation-induced stress redistribution was confined to within 1/2 of a shaft radius. Calculated stress changes indicate this damage is likely to be completely
placement of a relatively stiff seal. This example may be relevant to rock salt damage and healing adjacent to a panel seal as well.
Confidence in and further applications of this approach require healing data under deviatoric stresses, and further development of a damage model for rock salt which includes time-dependency.
The Small-Scale Mine-By was an in situ experiment to measure changes in brine and gas permeability of rock salt as a result of nearby excavation. A series of smallvolume pressurized brine- and gas-filled test intervals were established 8 m beneath the floor of Room Ll in the W
were isolated in the bottom of the 4.8-cm diameter monitoring boreholes with inflatable rubber packers, and are initially pressurized to about 2 MPa. Both brine- and gas-filled test intervals were located 1.25, 1.5, 2, 3, and 4 r from the center of a planned large-diameter hole, whe
hole. Prior to the drilling of the large-diameter borehole, the responses of both the brine- and gas-filled test intervals were consistent with the formation modeled as a very low permeability, low porosity porous medium with a significant pore (brine) pressure and no measurable g
mine-by borehole created a zone of dilated, partially saturated rock out to about 1.5 r. The formation pressure increases from near zero at 1.5 r to the preexcavation value at 4 r. Injection tests reveal a gradient of brine permeabilities from 5x10-18 m² at 1.25 r to about the pre-ex
injection tests reveal measurable gas permeability is limited to within 1.5 r.
Discontinuous behaviour is being observed and measured in the vicinity of excavations constructed in a bedded salt formation 650 m below ground surface for the Waste Isolation Pilot Plant (WIPP) Facility. The 2 m thick salt layer in the immediate roof acts as a beam, shearing
seam. Vertical separations between the immediate roof layer and the overlying strata are often observed at the anhydrite clay seam above the centre of excavations of larger span (11 m). The floor of the excavations is comprised of a 1 m thick salt layer underlain by a 1 m thick
(referred to as MB 139). Fractures in MB 139 develop beneath most excavations, with increased fracture frequency with drift span and age. In the excavations of larger span (11 m), MB 139 eventually debonds along the underlying clay layer. The salt layer overlying MB 139 dev
In a few locations below excavations of large span, continuous fracture systems are developing from rib to rib through MB 139 and the overlying salt. In the ribs, there is limited fracturing within the first metre of most larger excavations. Vertical fractures develop in pillars at most
behaviour is qualitatively consistent with analyses of the formation behaving as a layered medium (elastic beam analysis) and limited tensile and compressive failure of the rock salt. The significance of the discontinuous behaviour is that it can dominate the effective fluid transp
Numerous gas flow measurements have been made at the Waste Isolation Pilot Plant (WIPP) Facility horizon during 1988. All tests have been pressure decay or constant pressure tests from single boreholes drilled from the underground excavations. The test fluid has been nit
as permeabilities and porosities by means of a transient numerical solution method. A closed-form steady-state approximation provides a reasonable order-of-magnitude permeability estimate. The effective resolution of the measurement system is less than 10-20 m².
Results indicate that beyond 1 to 5 m from an excavation, the gas flow is very small and the corresponding permeability is below the system resolution. Within the first meter of an excavation, the interpreted pemeabilities can be 5 orders of magnitude greater than the undisturbe
interpreted permeabilities in the region between the undisturbed region and the first meter from an excavation are in the range of 10-16 to 10-20 m². Measurable gas flow occurs to a greater depth into the roof above WIPP excavations of different sizes and ages than into the rib
formation surrounding the smallest excavation tested are consistently lower than those at similar locations surrounding larger excavations of comparable age. Gas flow measured in the interbed layers near the WIPP excavations is highly variable. Generally, immediately above
Numerous gas flow measurements have been made at the Waste Isolation Pilot Plant (WIPP) Facility horizon from 1984 through 1986. Almost all tests have been constant-pressure or pressure-decay tests from single boreholes drilled in the underground excavations. Results in
excavation, both halite and interbeds (anhydrite and clay layers) allowed very low gas flows, and calculated permeabilities are below 1 microdarcy. In regions within 2 m of an excavation, very high flow rates were measured in the interbeds immediately above and below an exca
from near the center of the excavation. Further, measured flow rates increase with the width of the excavation. The halite also permits substantially greater gas flow within about 1 m of the excavations. Limited tracer measurements reveal that flow paths in both the halite and int
significantly larger than those in the presumed undisturbed condition. The gas flow measurements are consistent with the development of a (perhaps partially-saturated) dilatant zone (increased porosity) around the excavations. Considerable uncertainty is associated with perm
measurements, due to unknowns of rock saturation. entry pressure effects, flow homogeneity, etc.
Observations based on these gas flow measurements will aid in understanding the behavior and response of rocks surrounding the WIPP Facility excavations. The implications of these measurements for seal design are useful, particularly in assessing the degree of seal bypas
The performance of seal systems in rock salt formations can be dominated by the increased permeability of the damaged rock adjacent to an excavition. Under favorable stress conditions this damaged region is expected to "heal" and return to a condition comparable to intact ro
for first predicting excavation-induced damage of rock salt, and then the potential for its subsequent healing. This method avoids the necessity for developing complicated coupled models for damage and healing processes, and is appropriate for locations where conditions favo
develop quickly such as adjacent to a relatively stiff seal. Predictions are consistent with field and laboratory measurements, and suggest that healing will occur within a few years after emplacement of a cementitious seal.

Gas permeability and porosity measurements have been made during hydrostatic and triaxial quasi-static, stress-rate controlled compression tests. The permeability and porosity of the as-received samples decrease significantly as a result of hydrostatic loading. These changes
believed to "heal" or return the rock to a condition comparable to its undisturbed state. The permeability can increase more than 5 orders of magnitude over the initial (healed) state as the samples are deformed during deviatoric loading. The gas permeability and porosity chang
based on the equivalent channel concept. A model of microcrack initiation and growth based on the frictional sliding crack suggests the flow paths initially develop along grain boundaries and then along axial intragranular tensile cracks. Post-test visual observations support the

Changes in brine and gas permeability of rock salt as a result of nearby excavation (mine-by) have been measured from the underground workings of the WIPP facility. Prior to the mine-by, the formation responds as a porous medium with a very low brine permeability, a signific
measurable gas perrneability. The mine-by excavation creates a dilated, partially saturated zone in the immediate vicinity of the excavation with an increased permeability to brine and a measurable permeability to gas. The changes in hydrologic properties are discussed in the
Laboratory measurements of the argon gas permeability for rock salt specimens from the Waste Isolation Pilot Plant (WIPP) site in Southeast New Mexico (SENM) are obtained by using a transient, pressure step technique. Permeabilities of seven specimens are investigated as
and time. These data, when evaluated with the results of other authors, lead to the conclusion that if this formation is in a state of hydrostatic compression in its undisturbed state, then its in situ permeability is less than 5 x 10-20 m². And, if any connected porosity is introduced i

Laboratory measurements of the argon gas permeability for rock salt specimens from the Waste Isolation Pilot Plant (WIPP) site in Southeast New Mexico (SEIIM) are obtained by using a transient, pressure-step technique. Hydrostatic and differential pressure states are investi
pressure and time. These data, when combined with the results of other experimenters, lead to the conclusions that the in-situ permeability of the undisturbed formation is less than 0.05 µd; the introduction of non-lithostatic stress states into the formation, as with mining, may pr
increase the permeability of the formation; and, hydrostatic pressure states applied for finite time periods tend to "heal" the formation to its original undisturbed state.




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In situ tests of rock salt for possible gas flow between boreholes were performed by Louisiana State University (LSU) personnel in the Jefferson Island (J1) mine of south Louisiana. The work reported here is part of a more extensive and general study currently being carried out
compressed air energy storage (CAES) in salt reservoirs.
A significant finding from this study was that detectable amounts of Freon-12 (F-12) gas apparently did not penetrate even 12 in. (305 mm) of salt between parallel boreholes over a period of approximately 4 hours. During the test F-12 pressure was maintained at 90-95 psi (620
parallel holes on either side were periodically checked with an electronic F-12 detector ("sniffer") with sensitivity of 3 ppm (manufacturer's literature).
Test holes were kindly drilled dry by Jefferson Island mining personnel so as to achieve approximately the desired configuration indicated in Fig. 1. (1)*. The lower 10 ft. (3m) of the holes were left open. This configuration was selected so that the salt tested would be essentially
confined. Further, finite element modeling (2) for similar sites indicated that relatively large values of confining stresses would be present around the test holes, "Dry" drilling of the holes insured that the salt to be tested would not be "glazed over" by contact with brine (3).
It is well known that pillars in many salt mines tend to fissure and spall (forming "scales") with time. In addition, pillar faces are subjected to blasting during mining which tends to fracture salt, a strain rate dependent material. That is, salt typically behaves as a brittle material whe
by stress waves caused by blasting (4). Thus, permeability tests performed with horizontal holes drilled to relatively shallow depths near the free faces of rock salt pillars should not be considered, representative of in situ salt masses
Two groups of previous workers investigating permeability of rock salt for possible hydrocarbon storage have reported widely varying results from in situ tests in the Weeks Island mine of south Louisiana.
Aufricht and Howard (3) employed a qualitative test (modified and used in the current study as reported here) in which they injected F-12 into holes drilled 12 ft. (3.6 m) into salt, with 3 ft. (.9 m) of open hole at the bottom. They reported, "after a few minutes, small but detectable
escaping along the salt face at horizontal distances of as much as 14 ft. from the point of injection". They also found permeability of salt (from laboratory tests) to be highly sensitive to apparent glazing effects from brine, i.e., permeability of salt was sharply decreased when subj
Mahtab, et. al. (5), reported from in situ tests that Weeks Island salt was essentially impermeable. And a predominant number of their test holes were deliberately located in "anomalous zones" (6) in the mine. However, their test holes were apparently drilled with brine, thus dire
(according to the findings of Aufricht and Howard).


To model the deformational behavior of any polycrystalline aggregate, it is necessary to account for, among other variables, the effect on flow stress of preexisting microstructures. For example, it is commonly observed that apparent steady state stress values, following an abru
rate, reach levels appreciably higher than those obtained had the test been carried out monotonically at the reduced conditions. This strengthening caused by the initial defor,-natiozi, has been attributed to barriers to dislocation glide during the second stage created by either s
forest dislocation networks (3,4). While both types of obstacles may be effective in impeding free dislocation glide in varying degrees, it is important to determine the dominant strengthening mechanism.
The strengthening effect of subgrain boundaries is attributed to those boundaries composed of closely-spaced dislocations which may serve as barriers to gliding dislocations (5), leading to a reduced creep rate and larger stress exponent (1). However, not all subgrain boundar
dislocation glide and the results from many experimental studies question the importance of subgrains as obstacles. For example, 20%Cr-35%Ni steel (6), begins to form subgrains during secondary creep instead of primary creep, as has been generally believed. Aluminum defo
misorientation angles increased by a factor of two (from about 0.5° to about 1.2°) over the strain range from the onset of steady state (e = 20%) to a strain of about 120% (7). Dislocation bands cutting across many subgrain boundaries in deformed NaCl crystals (8) also indicate
boundaries as barriers to dislocation motion. As a final example, the flow strengths of natural rocksalt specimens deformed at 100° and 200°C fell to single-stage values at 10-6 s-l following an abrupt decrement to 10-6 s-1 after 4% strain at 10-4 s-1 (9, 10). Subgrains, with an a
during the initial stage at 200°C but did not form at 100°C. Following the decrement to 10-6 s-1 in the test at 200°C, steady-state stress was reached by 1 % strain but 4% strain was required for the subgrain size to equilibrate with the stress. Thus, in these studies neither the oc
characteristics of subgrain boundaries altered steady-state creep rates or stress levels.
Free dislocations in any crystal that has experienced slip on more than one plane form three-dimensional networks during deformation at elevated temperature (3). The networks consist of large numbers of meshes and polygons of varying sizes. Dislocation lines, or links, const
are pinned at their ends, or nodes, by the elastic interaction of intersecting dislocations. Under applied stress, a given link bows in its glide plane into an arc with a radius of curvature fixed by the shear stress resolved on its slip line (11). The bowed links may break free from the
The rheological properties of rock salt are of fundamental importance in predicting the long-term evolution of salt-based radioactive waste repositories and strategic storage caverns, and in modelling the formation of salt diapirs and associated oil traps. The short-term high rheo
laboratory experiments; however, extrapolation to appropriately low stream fails to predict the rapid flow men in certain natural structure. Furthermore, experiments have failed to reproduce the recrystallized microstructure of naturally deformed salt. Here we report experiments i
can be explained by taking into account the influence of trace amounts of brine. Trace brine is always present in natural salt but sometimes escapes during experiments. Our tests on dry dilated salt show more or less conventional dislocation creep behaviour, but brine bearing s
low strain rates. This is associated with dynamic recrystallization and a change of deformation mechanism to solution transfer creep. Because natural salt always contain some brine these results cast substantial doubt on the validity of presently accepted dislocation creep laws
behaviour of salt in nature.
This work deals with two topics.
First, - as observations on naturally deformed salt rocks indicate that brine has been present in these during salt metamorphism, and that this brine has strongly effected rheological behaviour -, the effect of saturated brine on the rheological properties of polycrystalline carnallite
(MgCl2O) was investigated. Second, - as salt minerals are good analogues for other rock forming minerals -, a fundamental study of microstructural evolution during dynamic recrystallization was carried out.
Most of the experiments on carnallite were performed using starting material obtained from the Asse salt mine in W-Gemany. Microstructural analysis of this material (chapter 2) indicates a history involving three processes: grain boundary migration, progressive misorientation o
the fluid phase. Detailed investigation of hematite inclusions found in the carnallite (which give the carnallite its red colour) reveals that these are decorating dislocation networks. This provides strong evidence that the hematite was precipitated after formation of the carnallite.
Experimental deformation of the carnallite has been carried out at T 60°C, confining pressures between 0.1 and 31 MPa, fluid contents up to 2.5% and strain rates between 10-4 and 10-8 s-l, (chapter 3). At a relatively high strain rate (5 x l0-5 s-1), rheological behaviour depend
pressure, brine content and content of other phases, with a general weakening towards increasing brine contents. Deformation also results in an up to 1% dilatation, associated with an about two orders of magnitude increase in permeability.
Experiments at lower strain rates show power law creep with a stress exponent between 4 and 5 for wet samples.
Deformation mechanisms are intracrystalline slip, twinning, cracking and displacement along grain boundaries. Recrystallization is strongly enhanced by the presence of brine. At low strain rates, however, overgrowths start to appear at dilatation sites, indicating that diffusive m
important and may become rate controlling at even lower strain rates. Microstructures in these samples are very similar to those found in the naturally deformed material.
Experimental deformation of bischofite (chapter 4) was carried out on artificially prepared samples at temperatures between 40 and 100°C, confining pressures between 0.1 and 28 MPa, and strain rates between 10-4 and 10-8 s-l.
First, at a strain rate of 10-5 s-l, the effect of grain size, impurity content and water content on the flow behaviour was investigated. Addition of 0.1 wt% water was found to decrease the flow stress by a factor of 5.
Second, the strain rate sensitivity of the flow stress in selected samples was investigated. Two regimes could be distinguished one with a stress exponent n=4.5 in the power law creep equation for values of the differential stress above 2.0 MPa, and one with n=1.5 for stresses b
Deformation mechanisms were intracrystalline slip, twinning and grain boundary sliding. Recrystallization occurred by subgrain rotation and grain boundary migration. Brine was found to strongly enhance recrystallization. Before and after deformation, brine was found in fluid inc
To get more insight into microstructures during deformation, 0.1 mm thick samples of carnallite and bischofite were deformed in-situ under the optical microscope (chapter 5). Microstructural evolution was correlated with observations made on thin sections of deformed samples.
In the case of bischofite, a number of interesting additional observations were made in the in-situ experiments.
(a)grain boundary migration rates fell into two different regimes, one of about 0.1 x 10-6 m/s and one between 1 and 10 x10-6 m/s. Sudden changes of grain boundary migration rate were observed.
(b)Microstructural evolution during dynamic recrystallization was characterized by the coalescence of grains, cutting up of grains, and cyclic changes in a grain's size. By these processes, "orientation families" developed.
(c)grain boundaries during migration were optically clear. This, together with the observation of necking-down processes, led to the conclusion that migrating grain boundaries contain a fluid film (about 50 nm thick) which develops into an array of fluid inclusions after the bounda
Chapter 6 is an attempt to incorporate the in-situ observations into existing theories of recrystallization. A classification of recrystallization into seven regimes is proposed, based on the relative importance of the three processes "slow" and "fast" grain boundary migration, and pr

The manner in which solution caverns fail and the way in which migration of stored products occur in the event of such failure is generally misunderstood. It is necessary that the stresses imposed on a solution cavern as a result of storage operations be thoroughly understood a
mechanisms of cavern failure before adequate precautions can be made to prevent failure. Eleven potential failure modes are discussed herein. The manner in which crude oil could migrate from the cavern in the event of failure, the degree to which such migration might progre
stored crude oil in natural occurring traps is also discussed. The migration of crude oil is used as an examnple because of the major emphasis now being placed on the Strategic Petroleum Reserve Program and the general body of knowledge relating to the characteristics of oil
domal salt formations. The migration of gaseous phase stored products and those having a low specific gravity or high vapor pressure could be quite different from crude oil. One scheme for storage cavern wellhead instrumentation and controls sufficient to restrain operating co
Tests were carried out upon halite to determine the effect of different humidity levels, and of immersion of the specimen in saturated brine or water, upon the creep rate. Tests were also performed to discover how long it took specimens of halite to reach equilibrium when placed
the same relative humidity as those in which creep tests were carried out.
It was found that the creep of halite is affected by the relative humidity of the atmosphere, especially above 75% R.H., when solution of the sample occurs. Below 75% R.H. no detectable solution occurs, but creep is still affected by the humidity: the mechanism for this is uncerta
effect.
Creep in saturated brine is affected by recrystallisation of the sample, as is creep at R.H. levels of over 75%. Creep in water results in rupture due to solution.




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In this paper results are given of work in various countries in rather unrelated areas of research. Nevertheless, since the studies have been undertaken to better understand salt behaviour, both from mechanical and chemical points of view, some connection between the studies
contribution the geological conditions have been investigated that might promote or prevent the formation of salt domes from layers, in view of possible use of the latter type of formation. This was done theoretically by the finite element method, and a start was made with centrifu
samples from salt and overburden from the Bresse basin was measured and it was shown that a favourable condition exists in this region for waste disposal. In the German contribution various subjects are touched upon, one being the effect of water on the mobility in the early s
also shown that in the final stages the water content is very low and that the thermal release of water occurs at higher temperatures than 250 °C for polyhalites and, under the prevailing pressure, for carnallite at temperatures above 140 °C.
Regarding the mechanical properties in the German work evidence was found for an anisotropy in salt in such a way that fibre textured material under compression parallel to the fibre axis shows significantly higher strain that when tested normal to it.
One Dutch contribution presents results of laboratory and in-situ measurements at ambient temperatures in the Asse mine, with an acoustic method to detect the extension of cracks in stress-relieved locations, such as gallery walls etc.
In the laboratory, tests were done with cubic blocks of rock salt under 3-D loading. The structural changes in the rock salt could be followed clearly by means of acoustic travel time measurements. During the test decompaction and recompaction of the rock salt was observed as
macro cracks was clearly observed when the heater was suddenly switched off. A not relevant loading case however in a repository!
In the wall of an old room In the ASSE-mine two measuring holes were drilled. The area between the holes was examined, open fissures could easily be detected. The measurements in the area close to the wall of the room points to the occurence of micro-cataclasis is parallel
observation that this effects decreases according to the increase of the distance from the wall side. This research is of particular interest for detailed analytical modelling of i.e. pillars in a HLW-repository.
Another Dutch contribution describes results of studies on the effect of small amounts of water on the rheology of salt. The results imply that flow laws obtained for salt at rapid strain rates and/or low confining pressure (i.e. much of the preexisting rheological data) cannot be rel
The economic and safe utilization of cavities in rock salt for the storage of gas and oil or waste disposal purposes requires stable performance of the cavities. Beside that, for liquid-filled cavities, long-term sealing from the biosphere is of particular interest. In that case, the follow
from the rock mechanics point of view: the permanent tightness of borehole cementation has to be proved and the natural pressurization of the encapsulated fluid in the sealed cavity, due to long-term convergence, must not exceed the frac-pressure. It is shown that with the aid
of hydro-frac can be calculated. Frac pressure risk depends on the height and depth of the cavity, as well as on the pressure increase rate.
The effective pressure pe for measurements off fluid permeability < k > is shown to be (pc - spp) where pc is confining pressure, pp is pore pressure, and s depends on the topography of the fracture surfaces and rock type. Measurements of flow through simulated fractures by K
between 0.5 and 1.0. The analysis here suggests that < k >1/4 should be linearly related to ln pc. Data from studies by Kranz et al. [1], Brar & Stesky [2], and Jones [3] follow the theoretical relationship.
The use of hydraulic fracturing in elastic rock is described in terms of comprehensive hydraulic fracturing observations in rock salt in the Salado formation in southeastern New Mexico. Inelastic rock behaviour involves both rate-independent and rate-dependent permanent defor
volume tests in initially open, horizontal drillholes, finite-element analyses, and in situ fracture observations demonstrates that the pressure-time data in inelastic rock can differ fundamentally from those typically recorded in competent hard rock. Stable pressure-time signatures
peak and driving pressure are obtained in isotropic stress fields. Increasingly unstable records appear to be characteristic for anisotropic stress conditions. Qualitatively, the shapes of the pressure-time records of hydraulic fracturing tests in rock salt appear to be remarkably se
principal stresses normal to the fractures. Obtaining quantitative estimates of in situ stress magnitudes in rock salt and other highly inelastic rocks, however, hinges on the existence of reliable rate-dependent constitutive models in conjunction with relatively complex numerical a
greatest and least in situ compressive stresses are inferred from applications of elasticity solutions. Time-dependent effects on the characteristics of hydraulic fracturing in rock salt and associated difficulties in data interpretations arise if hydraulic fracturing is performed almost

Elf Atochem - Saline de Vauvert have been solution-mining a salt formation in Southern France for the last twenty years and there arises the problem of what to do with the deep caverns once brine production ceases. The wells are currently open and instrumented, but this situa
Elf Atochem - Saline de Vauvert and Géostock in close collaboration with Elf Aquitaine Production, have put forward procedures for sealing off the caverns to make them environmentally safe.
This paper is based on the report submitted to the regulating authorities further to a site study undertaken over recent years. It describes an experimental procedure for determining well-closure safety criteria and appropriate means of monitoring the reactions of the surrounding
A WIPP data base that characterizes brine movement and accumlation is summarized and analyzed. The data are interpreted in terms of a model for flow in a saturated porous medium. The model, summarized in this report, embodies the Darcy-flow assumption and storage due
salt and brine. Comparisons between model calculations and brine inflow rates measured in the WIPP show order-of-magnitude agreement for permabilities in the range of 10-21 to 10-20 m² (1 - 10 nanodarcies). These values of permeability are in accord with independent, in s
the salt. Expected accumulations of brine in typical WIPP waste disposal rooms were calculated by numerical methods using a mathematical description for the brine inflow model. The expected brine accumlation in a disposal room was calculated to be in the range of 4 m³ to 43
rooms, filled with waste and backfilled, are expected to be virtually completely reconsolidated due to host rock creep in about 100 years, preventing further accumulation of brine. Calculations show that water-absorbing tailored backfill materials can readily absorb the maximum
disposal rooms while maintaining adequate mechanical strength.
Solution wells in salt are used for either mineral production or space to store gases, liquid hydrocarbons, or wastes. During the well's operational lifetime, the pressure or flow at the wellhead is controlled. Abandonment of a solution well, however, introduces many questions. Wh
pressure in a plugged solution well? Will the plug hold? Will the salt hydrofrac? If the well is left open, what will the flow be from the wellhead?
In this paper, a simple analytical method is described for computing either the pressure buildup in a plugged well or the flow from an open well. Pressurization and flow predictions for a typical storage well are presented and compared to the results from a sophisticated finite ele
also used to predict the pressure buildup for two shut-in wells on the Warren Petroleum property at Mont Belvieu, Texas. The agreement between the measured wellhead pressures and the predicted pressures is quite good.


Proceeding from both the theoretical relations between initial fracturing and fracture propagation in tight saline rock and the prevailing stress state numerous results of in-situ investigations gained in several salt deposit areas are interpreted in a uniform mode. Data are estimate
of maximum working pressure in cavern storage. The results obtained are also important in designing sealing measures in potash and rock salt mining.
The apparatus is used for the preservation and maintenance of wells filled with liquid media, in particular caverns in evaporites, following termination of usage. Below the well seal a container is positioned containing the sealant/protective medium, the walls of which vessel are m
material which is heavily corroded by the content of the well and which decomposes as a result. If as a result of geomechanical processes the gas cap is displaced and the level of the liquid rises up to that of the container then the corroded metal is perforated and the sealant ca
spread across the surface of the liquid.
Improvement of saltrock creep laws requires microscopic mechanisms incorporation, adequate tests, appropriate equation forms, and better use of field data. A low-stress pressure solution mechanism, affected by grain size, may he important for field modelling, leading to a stre
with sufficient moisture content.
Small-scale cementitious seal tests in rock salt are being conducted at WIPP by Sandia National Laboratories. Measurements of the mechanical behavior from these tests are compared to numerical modeling results. Factors considered in the numerical model were the heat of h
creep, and chemical expansivity of the concrete and the creep of salt. Based on the comparison, salt creep and concrete chemical expansivity seem to control the early-time response of the seals, while salt creep dominates the long-term response. Permeability testing indicates
immediately surrounding the borchole were effectively sealed.

In this paper permeability investigations of homogeneous model salt cores using a triaxialpermeameter are introduced and discussed. Of major interest was the influence of stress on the gas flow through the core under different water saturation conditions. In experiments outer
100 MPa while pressure at the entrance of the pores was differed between 0.5 MPa and 15 MPa. The results showed a clear dependence of gas permeability on the inner and outer stress. Furthermore it could be proved that the permeability behaviour is to a great extent subjec
The relation between friction constitutive behavior and the mechanisms of shearing in a monomineralic, polycrystalline material that deforms by combined cataclasis and crystal-plasticity has been investigated by shearing thin layers of halite between blocks of quartz sandstone
normal stresses between 20 and 70 MPa, and shear-displacement rates between 300 and 0.030 mm s-1 in a triaxial rock deformation apparatus. Constant and stepping displacement rate modes of testing were utilized, and some tests were preceded by a confining pressure (Pc
reduction of Pc after establishing a differential axial load. Pc-reduction causes the shear stress to increase as the normal stress approaches zero, and , promotes compaction and the formation of a slip surface in the halite at small shear displacements relative to that for constan
paths. Discrete changes in the steady state microstructure and constitutive behavior of halite with normal stress and displacement rate define distinct mechanismfields of frictional faulting. Cataclastic mechanisms dominate at normal stresses less than 40 MPa and at all displace
of friction varies from 0.6 to 1.0 as a function of displacement rate. Relatively large magnitude rate-weakening is observed at high displacement rates and is associated with stick slip sliding on a discrete surface. Because steady state shear involves localized slip at these condit
The shallow north German salt domes appear to be ideal locations for natural gas storage caverns or as repositories for nuclear and hazardous waste. One of the most important conditions to be met for the safe operation of cavern storages is the impermeability of the enclosing
cavities created by mining is considerably disturbed for long periods of time as a result of this activity. This can lead to changes in the permeability and porosity in the area proximal to the emplacement chambers.
This work was carried out with the objective of investigating the effect of various factors on permeability, and primarily the influence of external loading and the internal pore pressure, as well as fluid loading and temperature. The investigations were carried out in a triaxial perme
cavern wells, as well as on model salt cores made out of salt granulate.
The following parameters were varied systematically as part of the test programme: the isostatic and anisotropic external loads were varied between 5 - 60 MPa, and the gas injection pressures were varied from 1 to 20 MPa. The tests revealed that permeability decreases expon
radial loading. No significant change occurs by increasing axial load.
A considerable increase in permeability was determined for each different load with a gas injection pressure/relocation pressure ratio of 0.9 - 0.95 under isostatic stress conditions. This increase can be attributed to the formation of microfractures as well as a reduction in capilla




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Previous experiments on the effect of a fluid phase in deforming rock and rock analogue systems have failed to differentiate between the relative roles of stress and permanent strain in controlling preferential dissolution at fluid-grain boundary interfaces. Experiments are describ
were loaded under dry conditions, followed by removal of load and immersion of the crystals in brine. A correlation between net dissolution rate and plastic strain of the adjacent crystalline material was then observed at free crystal surfaces. Calculation of the increase in free en
deformation indicates that plastic strain should play a greater part in controlling dissolution than elastic strain in the experimental design reported here.
Although pressure gradients or differences in normal stress may dominate over strain energy terms in producing solution transfer or diffusion through disordered phases in natural rock systems, these halite-water experiments demonstrate that caution must be used in interpretin
other observations of the phenomena now commonly referred to as "pressure solution".
After a review of the basic coupling phenomena for salt subject to gas and /or brine migration, Thermodynamics of Open Porous Media is used to set up a model taking into account Thermal, Hydraulic, Chemical and Mechanical couplings. The model is simplified and applied to
results show that the structure response is very sensitive to hydro-chemical effects which change the thermo-mechanical behavior of salt.
The creep strain rate e of rocksalt, like that of other ductile crystalline materials, can be described by a power law equation of the type ea(oa)n where the active stress oa is the difference between the total deviatoric applied stress o and an internal stress oi. In this paper, the ori
stress, which develops during inelastic deformation of the material, are discussed. It is shown that this internal stress can serve as an internal (or state) variable in the constitutive model of rocksalt, which reflects the microstructure evolution of the material under the competitive
mechanisms.
An analysis of experimental data, both our own and those taken from the literature, demonstrates that such a law is able to correctly reproduce rocksalt creep test results in the steady-state domain. The proposed model is in accordance with the macroscopic and microscopic be
measurements of the internal stresses made by others on this material.
The need for storage caverns (oil, gas) and depositories (radioactive waste, toxic chemical waste) is rising world-wide. Rock salt (halite) formations are particularly suitable for the construction of cavities for such purposes. Rock salt is practically impermeable to gases and liquid
provides the means for the creation of large storage capacities at economic costs and, due to its favourable geomechanical properties. halite remains stable over long periods of time without support. Moreover, it can be shown that underground depositories in salt are safer from
compared with conventional depositories in shallow ground.
However, safety analysis has to be carried out in each case based on specific site-investigated data. The geotechnical behavior of rock salt is well-known, with sufficient details for dimensioning purposes. For liquid-filled cavities, long-term scaling from the biosphere is of particu
topics have to be investigated from the engineering-geological viewpoint : the permanent tightness of borehole cementation has to be proved and it must be shown that the natural pressure rise in the closed cavity due to long-term convergence does not exceed the frac pressure
fracturing can be calculated with the aid of finite element computations. Hydraulic fracturing depends on the height and depth of the cavity as well as on the pressure increase rate.
Uniaxial tests with stepwise variation of the relative humidity f of the surrounding air show that steady state creep rates are increased by a factor of about 55 between f = 0 and 75 %RH. Triaxial creep tests with stepwise variation of the confining pressure p show that steady stat
of about 30 between p = 3 and 0.1 MPa. This humidity induced creep is explained with moisture assisted in situ recrystallisation at points with stress concentrations caused by strain hardening at the contact of grains. This effect is possible only at low pressures p in the vicinity o
is dilatant and thus permeable for the moisture. An empirical function has been formulated describing the change of steady state creep rate as a function of f and p.

-
The Delaware Basin of southeastern New Mexico contains ~ 1000 m of layered evaporates. Areas in the northern Delaware Basin, bordering the Capitan reef, have anomalous seismic reflection characteristics, such as loss in reflector continuity. Core from holes within this zone
and extension structures. On a larger scale, anticlines and synclines are indicated by structure contours based on boreholes. The deformation is probably gravity-driven. Such a process is initiated by basin tilting during either a Mesozoic or Cenozoic period of uplift. The age of
Permian to Recent.small-scale structures suggest that deformation was episodic with an early, syndepositional stage of isoclinal folding. Later, open-to-tight asymmetric folding is more penetrative and exhibits a sense of asymmetry opposite to that of the earlier isoclinal folding.
development of zonal crenulation cleavage and microboudinage of more competent carbonate layers. At the same time, halite beds developed dimensional fabrics and convolute folds in anhydrite stringers. Late-stage, near-vertical fractures formed in competent anhydrite layers
anhydrite porphyroblasts, stress shadow growth, and microboudinage. Except during late-stage deformation, anhydrite and halite recrystallized synkinematically. Drastic strength reduction in anhydrites through dynamic recrystallization occurs experimentally near 200°C. Howev
Evaporite sequences have been intensely studied for hazardous waste disposal and hydrocarbon development: and storage. Rates of deformation are important in evaluating the long-term performance of different evaporites. Reported naturally occurring strain rates (x) are: 5 x
mine closure; 3 x 10-14, 10-15, and 10-16 for salt domes; 3 x 10-16 for bedded salt. Rates are controlled by temperature, differential stress, and active mechanism of deformation for each specific type of evaporate and setting.
Strain rates are estimated through in-situ measurements and the integration of geometric strain analysis and stratlgraphic arguments for the time required for the observed deformation to occur. An inherent problem in such calculations is the large extrapolation of rates through t
estimation is to calculate x directly, using the constitutive models for different deformation mechanisms that may be dominant. Specific mechanisms can be determined from petrofabric study, as at the WIPP site, SE New Mexico, where textures indicating that pressure solution w
based on experimental data are limited by the relatively poor data on diffusion in intergranular fluids. A variety of grain boundary diffusion models have been used. Some models (e.g., cubic approximation of the grain shape) leave gradients undefined at the grain edge.
For gravity-driven deformation near the WIPP site, geometric-stratigraphic integration predicts a x of 10-14 s-1 to 10-16 s-l. Strain rates of 10-15 to 10-16 s-1 are predicted using models for dislocation creep and pressure solution. The rates using two approaches, geometric-stra

In the experimental research we present here, we demonstrate that sampling damage causes opening of grain boundaries and generation of sufficient microfractures as to significantly affect mechanical properties. We show through CAT-scan experiments that sampling damage
hydrostatic stresses. We demonstrate that unconfined and confined compressive strength of salt rock are strongly influenced by this healing process. Finally, we validate a test procedure, and we prove that transient creep of salt rock can be evaluated using a series of compres
Experiments were conducted under various stress deviator and mean stress levels from one cycle to another; the results obtained are consistent with our interpretation of annealing, and have led to the development of a phenomenological model for salt rock.
Knowledge of the state of stress in salt rocks plays an important role in dimensioning the size of cavities and the pressure load in underground storage. By laboratory tests the questions and problems occurring in them cannot be solved clearly. Therefore, in situ tests are necess
reported. wherein salt rock boreholes gas pressure was produced up to fracturing of the originally impermeable rocks. Connections appear in outline between the mechanical strength of the salt rocks, the presence of so-called etching pits, the strain behaviour and the pressures
fracturing in salt rocks in situ.
The in situ test conducted in the Potash Mines of Alsace is designed to measure the permeability of a salt formation to gas and brine for purposes of long-term safety assessment of a radioactive waste repository. This paper describes work relating to the design and deployment
comprised of seals, a resin sealant, a fluid injection system, data acquisition systems for temperature and pressure and a heat regulating device for the test.

When solution-mined caverns are sealed, rock-salt creep and brine heating generate a brine pressure build-up which in many cases leads to fracture. Brine seepage through the rock-mass mitigates pressure build-up and can prevent fracturing.
The results given in this paper deal with experimental and theoretical studies performed on rock salt permeability, in the framework of hydrocarbon or radioactive waste storage. The results of a field experiment carried out in a salt layer in the Mines de Potasse d'Alsace is in agr
performed in other salt formations : rock salt is permeable to gas and to brine, at least around underground facilities. Its permeability is about 10-21 m². This permeation is due to damage resulting from excavation or tectonics.
Considering rock salt as a porous, permeable and reactive medium, a theoretical framework is used to discuss two phenomena playing a role on permeability: (a) dissolution/crystallisation in microcracks due to brine solubility changes (b) healing process due to hydrostatic load
agreement with those of laboratory tests, and show that a mechano-chemical coupled effect associated with viscoplastic deformation of grains can explain the extremely low permeability of rock salt at a geological time scale.

In order to measure rock salt intrinsic permeability located far from underground facilities, an in situ experiment was performed in the Amélie mine belonging to the Mines de Potasse d'Alsace (MDPA, Mulhouse, France). A vertical borehole was drilled from a niche excavated to
halite. The selected salt bed is approximately one meter thick and is located 16 meters away from the gallery floor. Test fluids were nitrogen and saturated brine. In order to minimize and to control disturbing phenomena (thermal effects, solution/crystallization and creep), consta
tests were recommended. As a matter of fact and because of the geological conditions (low thickness of the tested halite bed), a special device had to be designed and its principal components (packers and fluid injection systens) needed to be tested in the laboratory and in the
The results of the field experiment show that rock salt is permeable to gas and to brine, even far enough from underground openings.
The results of the tests with brine are interpreted in a satisfactory way using a model based on the Darcy's law and characterized by a permeability value of 2 x 10-21 m2 and an initial pore pressure value of 1 MPa. Analysis of measured gas flow rate shows that :

- after a brine percolation, capillary pressure effect is significant

- fluid migration in salt is not controlled by Darcy diffusion, Knudsen effect and partial saturation
may play an important role.




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The results of a field experiment carried out in a salt layer in the Mines de Potasse d'Alsace (France) confirm that rock salt is permeable to gas and to brine, at least around underground facilities.
A simple analysis of measured gas flow rate shows that (a) capillary pressure effect is significant (b) fluid migration in salt is not controlled by Darcy diffusion.
The results of the tests with brine are interpreted in a satisfactory way using a model based on Darcy's law characterized by a permeability value of 2 x 10-21 m² and an initial pore pressure value of 1 MPa. The following non linear effects are considered : (1) salt damage create
stress changes (3) change in salt concentration of brine saturation state resulting from pressure changes.

An in situ experiment is being performed in the Mines de Potasse d'Alsace (M.D.P.A., Mulhouse, France) in the framework of a C.E.C. contract (coordinator: ANDRA, contractor: G.3S, technical assistance : COSEREP). The objective of this test is to measure the permeability of
This paper deals with the experimental procedure, the measurements, and the first interpretation of the results.
Two tests with nitrogen under the pressure levels of 4 and 6 MPa, and three tests with brine under 2, 4 and 6 MPa of pressure have been performed. The experiments are completed with three more tests, again with gas under 2,4 and 6 MPa. These last tests allow to check tha
to brine is not permeable to gas regarding capillary effects.
The experimental set up is capable to measure very low values of permeability about 10-21 m². The basic flow mechanism involved in gas flow is possibly a multiphase flow for which capillary pressure may play an important role. On going and further studies will allow the final in
results.
The elastoviscoplastic behavior of saltrocks may be interpreteted in terms of a number of different fundamental deformation mechanism that act at different rates at different shear and normal stress levels. The paper presents a new approach to a constitutive law for these mater
behavior, and making distinctions between different types of yield criteria and viscous flow laws. An attempt is made to develop this behavior as an analogue to the behavior of rock at high temperatures and stresses, where viscous mechanims become possible. It is emphasised
deformation mechanisms acting at particular conditions will guide the form of macroscopic constitutive laws for non-saltrocks.
An important operational parameter for an underground gas storage cavern produced in salt by solution mining is the maximum admissible gas pressure coefficient and the elated mayimum admissible operating pressure for the storage cavern.
In cooperation between the VEB Kombinat Gasanlagen, Mittenwalde (GDR), the Thyssengas GmbH, Duisburg, and renowned scientists from the GDR and the Federal Republic of Germany, in-situ measurements to assess the maximum gas pressure capacity of the salt were su
in the Federal Republic of Germany employing a testing process developed in the GDR.
The work carried out has been supported by the competent mining authority and the results obtained from the basis for the mining authority's approval of higher maximum internal pressures at underground gas storage caverns in Xanten.
Parameters which have a significant influence on the determination of maximum cavern internal pressure were derived from the available investigations for determining the maximum pressure in salt caverns (fig. 7-1). Although the formation pressure is the critical parameter, the
behaviour - with their influence on the determination of maximum pressure - cannot be ignored. Moreover, a combination of single factors also affects the maximum pressure. Thus, the loading history in combination with the creep behaviour and the location of the cavern in a fie
field for assessing the maximum pressure which could not be determined from a single parameter. The new "concept for determining maximum pressure in salt caverns by establishing boundary conditions" proposes the use of safety zones and a minimum pressure stress for the
maximum pressure. The maximum pressure can be determined on the basis of numerical calculations in combination with the determination of permeability in the surrounding rock.
The maximum pressure determined in this way can be used to guarantee the sustained stability and tightness of a storage cavern during its operating period. The proposed criteria for this are:
(1) The maximum internal pressure must be smaller than the formation pressure! The reference depth is the casing shoe of the last cemented casing string,
(2) There must be a zone which is unaffected by the stress relocation associated with the alternating stress in the roof zone! This zone is designated the "primary sealing zone".
(3) There must be a zone in the area of the secondary stress field created by the alternating internal pressure that prevents the propagation of leakiness under maximum pressure conditions. This zone, which is designated "safety zone II" must be seen in connection with the pri
interact and are time-dependent.
(4) A minimum pressure stress for the tangential stress is proposed to avoid fracturing of the cavern wall. This assumes a loading history involving a sudden internal pressure increase from minimum internal pressure to maximum internal pressure.
One cannot exclude the possibility that the storage medium infiltrates the rock in the proximal cavern wall zone. This zone may be restricted to the immediate area of the storage cavern wall if the maximum pressure is determined in compliance with the recommended criteria.
Moreover, it is a basic fact that the pressure release rate not only influences the minimum internal pressure through the lower stressing of the cavity wall and smaller volume convergence, but that advantages are also apparent for lower loading rates at maximum pressure in the
Axisymmetric triaxial tests have been performed on rock salt, and global volumetric strains were measured. Initiation of damage is supposed to be linked to the change of curvature of volumetric strain from compressibility to dilatancy due to microcracking. The results are interpr
stress space in order to identify the damage and its evolution, using the classical formalisms of plasticity or the plasticity associated with damage.
In this paper we describe the microstructures of naturally deformed rocksalt samples from the Asse salt anticline, FRG, as revealed by a chemical polishing-etching procedure, and by gamma-irradiation. Evidence is presented for the operation of dislocation creep processes, ac
grain boundary migration. Grain boundaries can be shown to have contained thin brine films during recrystallization, suggesting that solution-precipitation processes could also have been important deformation mechanisms. Recrystallization and solution transfer processes hav
experimental work to date, thus casting doubt on the validity of extrapolating these data to predict the long-term creep behaviour of salt during natural flow.

measure permeabilities of rocks under thermomechanical stresses using the pulse decay method. This apparatus can measure permeabilities between 10-15 and 10-22 m².
Two calculation methods have been used: the first one, based on the Brace equation, is efficient for samples of ultralow porosity. The second one resolves numerically the diffusivity equation and is efficient for all types of sample.
Several thermomechanical tests, including intermittent permeability determinations, have been carried out on samples issuing from the Bresse basin saliferous lithofacies. The initial permeabilities are more representative of the state of the sample than of the in-situ formations. O
evolution during the thermomechanical tests seems to be directly conneced to the nature and torture of the material and express quiet well the structural evolution. For example the deformation tests under constant pressure and temperature show that, for all the lithofacies, the p
relation with the creep capacity of halite.

The results of a field experiment carried out in the Mines de Potasse d'Alsace (MDPA, France) show that rock salt is permeable to gas and to brine, at least around underground facilities (four radii far from the gallery wall). In contrast to gas flow rate, brine flow rate is interpreted
based on Darcy's. law. On the othcr hand, after brine percolation into the rockmass, capillarity has a significant effect on the gas injection flow rate.
During laboratory compressive triaxial tests, under high confining pressure (up to sixty Mpa) unjacketed samples of MDPA.salt show a lower damage initiation and a lower compressive strength than jacketed samples. These effects induced by salt permeability become more ma
fluid.
In the theoretical part, a framework is proposed and used to discuss dissolution/crystallisation phenomenon leading to a change of transport properties. The "healing process", associated with viscoplastic strains of grains can explain the extremely low permeability of rock salt at
Results of the calculations on underground structures show that a very low permeability which may not be measurable using existing techniques, modifies in a significant way the long term evolution of an underground storage.
A new apparatus is described for determining permeability (water) in geologic materials as a function of confining pressure (to 200 MPa), pore pressure (to 25 MPa), and deviatoric stress (500-800 MPa). The samples are relatively large (0.15 m diameter x 0.28 m long) and may
going fracture. Permeabilities of 10-11 - 10-24 m² (10 - 10-12 D) may be measured, simultaneously, with electrical conductivity and acoustic velocity and amplitude. Crack closure is also monitored for the fractured samples. All experimental control and data-acquistion functions
discussion of data-analysis techniques and typical data are also presented.
Excavated rooms in natural bedded salt formations are being considered for use as repositories for nuclear waste. It is presumed that deformation of the rooms by creep will lead to loss of structural integrity and affect room life history and seal efficiency. At projected repository
mechanisms in salt are creep-induced microcracking in triaxial compression and cleavage in tension. Thus, an accurate prediction of the time of room life and seal degradation requires a reliable description of the creep and damage processes.
While several constitutive models that treat either creep or fracture in salt are available in the literature [1-4], very few models have considered creep and damage in a coupled manner. Previously, Munson and Dawson [1] formulated a set of creep equations for salt based on th
mechanisms in the creep process. This set of creep equations has been generalized to include continuum, isotropic damage [5] as a fully coupled variable in the response equation [6]. The extended model has been referred to as the Multimechanism Deformation Coupled Frac
constants for the creep and damage terms was deduced based on test data for both clean and argillaceous salt [7-9].
In this paper, the use of the MDCF model for establishing the failure criteria and for analysing the creep response of a salt structure is demonstrated. The paper is divided into three parts. A summary of the MDCF model is presented first, which is followed by an evaluation of th
Practical experience already exists on the technical realisation of seals for underground cavities which, despite similar terms of reference and conditions, are not adequately taken into consideration in the conception of underground repositories. Only natural materials with confi
used for the long term safe sealing of underground repositories. In evaporite caverns, natural stone (basalt, rock salt blocks) can be used for static massive seals, and precompacted dry bentonite, or bitumen, asphalt or mastic asphalt for sealing elements. The use of crushed sa
possible under certain conditions. This paper concludes with details of a long term safe horizontal roadway seal. Long term safe shaft seals can be constructed using a similar basic concept.




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While the fluid transport properties of rocks are well understood under hydrostatic conditions, little is known regarding these properties in rocks undergoing plastic deformation. In this study the influence of macroscopic plastic deformation on permeability has been investigated e
rock. Dilatometric triaxial deformation experiments performed on this material. at room temperature, confining pressures (Pc) in the range 5-20 MPa and strain rates of - 4 x 10-5 s-1 to total strains of ~ 15%, exhibited work hardening behaviour with minor amounts of dilatancy at
observations confirmed that deformation occurred by dislocation glide, with grain boundary microeracking in the dilatant field. At the lowest pressures. deformation-induced ditatancy of only 0,1-0.2 vol.% produred extremely rapid initial increases in permeability (from < 10-21 m²
behaviour of the type described by percolation theory. This rapid permeability development with dilatancy is well described by crack linkage models based on percolation theory, provided a broad range of fluid conductance is incorporated. The study has shown that minor dilata
deformation n' salt rock can lead to very large increases in permeability. This is of direct interest with regard to the behaviour of salt rock in waste disposal and storage systems, and may have important implications for the transport of fluids through. and the interaction of fluids w
We analyzed the evolution of a single wavelength (l= 13.4 km) salt structure of initial amplitude Ao = 100 m by means of a 2D finite-volume numerical model. The model incorporated two laboratory-derived rheological laws for rocksalt: a low-stress, dislocation-creep power law (
creep law (e a s/Td³), in which e is strain rate, s is the equivalent stress, T the absolute temperature and d the grain size. Our model also accounts for salt thermal conductivity dependence on temperature. The models comprised 3.6 km of sediments overlying a 1.2-km-thick salt
between sediments and salt of 100 kg/m³ and sediments viscosity m2 = 3.0 x 10 to the power of 19 Pa s. We assumed that deformation is driven solely by buoyancy forces. Results predict that salt structures evolve faster (2- to 3.5-fold) in fluid-assisted models than in dislocatio
and viscosities predicted by the fluid-assisted law are lower than those predicted by the power law, by factors of 3, and 1 to 2 orders of magnitude, respectively, depending on the degree of structural maturity. In contrast, strain rates predicted by both rheological law., are nearly
degrees of structural maturity. Temperature distribution in the model domain was controlled by the thermal conductivity contrast between salt and sediments, the shape of the salt structure and thermal conditions imposed at model boundaries. At the early stages of evolution. a p
The finite element method is used to evaluate the mechanical response of a weilbore that is internally pressurized above lithostatic pressure. The uncased wellbore is emplaced in salt, a rheologic media. Salt creep tends to relax the stress state in the salt around the wellbore m
the wellbore without fracturing the surrounding salt. This is a very desirable sealing feature as plugging and abandoning a cavern typically results in wellbore pressures that exceed lithostatic pressure. The analyses show that the rate of pressurization determines the hoop stres
Pressurizing the wellbore above the surrounding lithostatic pressure reduces the hoop stress and, for very quick pressurization rates, the hoop stress can become tensile and fracture the salt. For most cavern fields, the pressurization rates after sealing and abandonment should
mechanically fracture the salt surrounding a plugged wellbore. In the long-term, however, other mechanisms may contribute to fracture, or to increase the permeability in the salt.
This report summarizes results from recent field tests that were performed for the SMRI project: "Hydrofracture Gradients in (U.S.) Salt Domes". This project was initiated in May, 1984, and a relatively detailed report was presented on the background of this project during the SM
special technical session on hydraulic fracturing of rock salt. Thus this presentation will emphasize field tests performed since that report. A detailed final report to the SMRI will provide a complete description of this project, and will include our analyses of field test data and its s
solution mined caverns in salt domes.
1) What is the "upper" limit on the pressure, in a sealed brine filled chamber, due to natural occurring forces?
2) What general effect would the numerous near vertical striations of differing salt compositions, variations of anhydrite in salt, and anhydrite have on the stress field surrounding the chamber (i.e., would it tend to be significantly distorted)?
3) Is it likely any of the above striations would be continuous over an extended vertical interval? Is there likely to be a significant difference in the mechanical "strength" of the varous striations?
4) If the pressure in a sealed chamber ever reached geostatic (i.e., the fracture gradient) at the exposed face of a vertical striation of significantly lesser mechanical strength, is it likely a long vertical fracture would occur?
5) What do we know about the nature of occurrence and probable extent of micro-fracture (i.e., area covered, width, orientation, length, etc.) resulting from over-pressure in a borehole? Is it likely they would be of the same nature and extent in the salt face of a large volume solu
subjected to a pressure in excess of geostatic?
6) Is it likely micro-fracturing would be concentrated in limited areas where "weaker" striations exist thus occurring at a pressure significantly less than geostatic?
7) What is the effect of aging on the strength of the commonly used oil field type cement (s)?
8) What is known in respect to the shear strength of common neat cement?
9) What might be the relative values of the shear strength of the salt in contact face area and that of the cement in the plug itself?
10) What is generally considered the maximum open hole diameter within which a plug can be set?
11) In the event it is impractical to emplace an open hole plug, what criteria should be set for mechanical integrity in the casing cementation?
12) What data, other than chamber brine pressure, should be manitered'in a sealed solution mined chamber? (Temperature, pressure on face of cement plug, shear stress within cement plug, etc.?)
-
Results are presented of shaft closure measurements based on a rather unusual emplacement of very early time closure points. These data are in good agreement with calculations based on the prediction to techniques developed for underground rooms in salt using a complete
calculational mesh also gives good agreement, which permits this model to be used for parametric studies of long term closures of open and brine filled shafts and boreholes.
This report describes experiments designed to provide data on brine migration in polycrystalline salt. Polycrystalline samples of various grain sizes, density, and purity were prepared from several commercial grade salts by hotpressing. Three distinct experimental set-ups were
thermal gradient in contact with a brine source. The test designs varied primarily in the way in the thermal gradient was applied and monitored and the way in which brine migration was determined. All migration was in enclosed vessels which precluded visual observation of brin
microstructure.
Migration velocities were estimated either by the timed appearance of brine at the hot face of the sample, or by determination of the penetration distance of migration artifacts in the microstructure after tests of fixed duration. For various reasons both of these methods were subje
results suggest, however, that the migration velocity in dense polycrystalline salt may be at least an order of magnitude greater than that suggested by single crystal experiments.
Microstructural analysis shows that brine prefers to migrate along paths of high crystalline activity such as grain and subgrain boundaries and isdispersed rather quickly in the microstructure. A series of tests were performed using various types of tracers in brine in order to flag
Hydraulic fracturing tests were carried out in horizontal drillholes in rock salt in the Waste Isolation Pilot Plant (WIPP) near Carlsbad, NM. It was determined that the virgin in situ stress field is isotropic or nearly isotropic. The inferred magnitude of the isotropic in situ stress falls
17.9 MPa for the average breakdown/reopening pressures and driving pressures. The best estimate from instantaneous shut-in pressures is 16.61 MPa. Given some uncertainties about the interpretation of hydraulic fracturing data in salt, all of the foregoing values are in accep
calculated isotropic in situ stress of 14.9 MPa at an average depth of 657 m below surface. Interpretations of breakdown and reopening pressures are based on finite element analyses of the relaxed stress field around a borehole in salt. This stress field varies little between app
drilling. The finite element analyses were also used to interpret the observed stable pressure-time signatures with little or no pressure drops during primary breakdown of the salt formation. The conclusion about the isotropic nature of the virgin in situ stress field is supported by
patterns. The report includes a comparison of the hydrofrac data in the WIPP with the published results of hydraulic fracturing tests in salt at three other locations.
This report summarizes the project work, "Ultimate Stress in the Salt Envelope of a Sealed Liquid-Filled Solution Cavern," conducted by Serata Geomechanics, Inc. (SGI) for SMRI. SGI's finite element code, REM, was used for the computer simulation portion of this study. The o
the fundamental mechanism of long-term behavior of a solution cavern sealed with a cement plug. The boundary conditions of the cavern development and the cement plugging procedure, as well as the overall scheme of analysis, are specified by SMRI in our contractual agree
The study was conducted in the following three phases:

Phase 1: Equilibrium Analysis
REM computer simulation analysis for the entire process of sequential cavern development, including temperature effects, was conducted with regard to the time-dependent behavior of the cavern. A computer model of the solution cavern was developed by closely simulating th
sealing the cavern, resulting in brine pressure build-up. This simulated pressure build-up was related to the material properties of the rock salt, and further compared with the actual pressure build-up data obtained in various field observations. By verifying the close interrelation
properties, and field observation, the REM model of the solution cavern was quantitatively established.

Phase 2: Plug Analysis
A REM simulation was conducted to examine plug stability during and after the pressure build-up stage by utilizing the stress-strain conditions established in Phase 1. The structural stability of the cement plug and surrounding ground were examined in this phase.

Phase 3: REM Validity Check
The validity of the REM program was confirmed and illustrated using two entirely different methods. One method compared behavior of the laboratory cavities tested at the SGI laboratory with the REM model of the same cavities. The other method compared results of the finite
published by Ghaboussi (5) with an identical run using REM.
The major factors incorporated into the REM simulation analyses were temperature effects and material properties. Not considered in this study were the chemical reactivity of the contained fluid and the effect of impurities in the salt mass. All other design parameters, such as s




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It must be expected that repositories for radioactive wastes situated in salt rock formations will, in certain zones, generate and release hydrogen. It must therefore be guaranteed to ensure long term integrity of the repository that this does not represent a hazard. In order to be in
statements concerning the location or transport of the hydrogen, it is necessary to acquire data on the permeation and diffusion behaviour of salt rock. To achieve this, a number of model salt cores were prepared using salt fines during which the following parameters were varie
compaction time, compaction pressure, mineralogical/chemical composition, grain size, moisture and temperature. These cores were then tested for hydrogen permeability and diffusion. In order to allow comparisons with natural salt rock, a number of salt cores were also inves
In order to prepare the test cores and to perform the comprehensive permeability and diffusion measurements under various parameters, a number of suitable test apparatus were constructed.
The tests were carried out using salt fines from the former Asse salt mine taken at various depths (Staßfurt and Leine series) and from the Bernburg pit (Leine salt rock). The cores tested were for the most part recovered from the Asse salt mine (Staßfurt series).
In order to quantify the various influential parameters, the salt specimens were analysed for chemical and mineralogical composition, grain distribution and their water content and absorption isotherms were determined.
In preparatory tests a number of different techniques were reviewed in connection with achieving diffusion-tight clamping of the salt specimens and the influence of the specimen diameter and the salt aggregate size on the permeability behaviour.
The results were used to perform the main tests using both original cuttings (recovered from a partial road header) as well as strained original material (< 10 mm) with in-part modification of anhydrite content.
The permeability tests on the salt fines samples were performed while varying type of salt, porosity (compaction density), mineralogical composition and time. Insodoing the permeability was found to be in a range of 10-12 m² and 10-23 m².
It was found that the salt dampness, the anhydrite and polyhalite contents, and the size of the grains had the most influence on reducing permeability over time (with appropriate overburden pressure) as well as with falling porosity.
Similarly the temperature of the compaction had a greater than negligible influence on the permeability behaviour of the specimens over time. In particular, the specimens compacted hot had a major difference in their pore structure (smaller pore radii, larger access porosity) tha
diffusion behaviour of the hot compacted specimens was considerably different to the cold compacted, even with the same permeability.
The experimentally proven connection between porosity and permeability allows two ranges to be identified. In the total porosity range between 7% and 1.5% the permeability drops exponentially from approx. 1·10 to the power of 13 m² to approx. 5·10 to the power of 17 m². The
salt dampness and mode of preparation (cold or hot compacted) has a virtually negligible effect in this range. Only those samples prepared with hygroscopic salt drawn from 490 m and 700 m depths were found to have a temporal permeability drop of up to four powers of ten do
level within only a few days in the porosity range between 1.5% and 5%. The specimen porosity after the measurement was found to be still in the order of 2%.
In the case of all salt types in the porosity range of < 1.5% the influence of all the above named parameters was found to be greater than negligible. Below this porosity the permeability of the salts with low anhydrite content fell dramatically down to the lower detection limit of k =
The decisive factor determining the permeability of the porous material is the accessible porosity of the flow medium. In order to determine the accessible porosity a number of methods were investigated. Determining the accessible porosity and comparing this with the overall p
compaction and the pressure of compaction have a decisive influence on the ratio on these two pore factors in compacted salt fines. In the case of samples prepared with low compaction pressure and long compaction time the difference between total and accessible porosity is
specimens compacted at high pressure.
Long term tests and an overburden pressure of 200 bar (creep compaction) allows a differentiation between samples with larger k <10-15 m2) and lower initial permeability. In the case of higher initial permeability (e.g. low compaction density, large porosity) the influence on the
permeability reduction is low - depending upon type of salt. However, the lower the initial permeability the larger the temporal permeability falls whereby this also depends on type of salt and salt moisture. In the case of intensively dried salt cores the influence on the overburden
drop is minor even for lower values of initial permeability.
Within the permeability measurements the influences resulting from the method of evaluation (Darcy equation) such as slip flow, turbulent effects and pore structure, were investigated as was their influence on the accuracy of the permeability measurement. The deviations resul
between the measured "apparent" and the "true" permeability are identifiable by suitable tests yet play only a subordinate role compared with the influential factors referred to above.
During the overall project over 400 salt core samples were subjected to permeability testing.
The testing of diffusion was undertaken on an apparatus with open, semi-open and closed systems using nitrogen and hydrogen as measurement gases. The system differences refer to the degree of freedom of the gas located on both sides of the salt specimen core in the hydr
The test conditions were adapted to the conditions found in the salt mine.

A simple model for rock deformation by pressure solution, assuming grain boundary diffusive mass transfer to be deformation rate controlling, is presented. The model leads to a constitutive flow law which is of the same form as that for Coble creep. It is argued that the presenc
boundaries leads to enhanced diffusivity of solute particles in the grain boundary. Some simple experiments are described, which demonstrate rapid diffusion in solutions in pores, much slower diffusion in stressed interfaces and deformation by pressure solution.
By using the theoretical model, and by assuming that the pressure of the interfacial solution is equal to the applied normal stress, so that available experimental data on the effect of pressure on mineral solubility could be used, rates of deformation by pressure solution have bee
with rates of deformation by crystal plastic and high temperature diffusive flow processes, by using deformation mechanism maps. Predicted transition conditions between various deformation mechanisms are found to be consistent with those inferred from the study of textures o

A permeability model is developed from triaxial flow test data to predict the permeability increase of rock salt around storage caverns, as affected by excavation, confining and internal pressures, age and shape. The confining and internal pressures may increase the surrounding
of 10-22 m² to as high as 10-16 m². The permeabilities increase with time and reach their ultimate value at within one year after excavation. Salt permeabilities around elliptical caverns are several orders of magnitude higher than those around the spherical cavern.

In response to interest regarding the effects of inflow brine on the strength characteristics of pillar support in soft rock mines, a laboratory research program which simulated the interaction of brine with potash and salt rock has been successfully undertaken. Potash and salt core
constant load conditions, both with and without added inflow brine. Factors such as brine temperature and axial load were varied in order to determine their relative effects on both deformation rates and dissolution chemistry. The results indicated a substantial increase in creep
of inflow brine. Elevation of brine temperature resulted in further increases in deformation rates. The dissolution experienced by the salt material was very small even at elevated temperatures while that of the potash increased considerably. The implications to mining are that in
the creep rates of evaporate ores through the enhancement of fracture mechanics processes as well as solution transfer creep. In potash ore, this weakening is compounded by the removal of supportive material through the selective dissolution of sylvite.

In a large in situ experimental room, circular in cross section, inflow of brine was measured over a five year period. After correcting the measured brine accumulation for initial losses by evaporation into the mine ventilation air, the measurements gave data for a period of nearly
accumulation based on a mechanical "snow plow" model of the volume swept by creep-induced damage as calculated with the Multimechanism Deformation Coupled Fracture (MDCF) model was found to agree quantitatively with the experimental results. The calculation sugges
effectively extends only some 0.7 m into the salt around the room. Also, because the mechanical model of brine release gives an adequate explanation of the measured data, the hydrological process of brine flow appears to be rapid compared to the mechanical process of brin
The effect of fluid pressures on the behaviour of salt has not been investigated thoroughly until now, since salt rocks at great depths have been considered impermeable and non-porous. Recent investigations have shown, however, that permeability of salts may be significantly
lithostatic pressures, which may have a large influence on the strength. This permeability increase is believed to be caused by the viscous micro fracturing at above lithostatic fluid pressures, or by shear dilatancy at sublithostatic fluid pressures and sufficiently large deviatoric s
permeability increase is that pressure communication between pore fluid and cavern fluid needs to be taken in account and salt needs to be treated as a Terzaghi material, splitting total stresses in effective stresses and pore pressures. Hence conventional cavern analysis with
loads rather than boundary pore-pressures may not be right for caverns with sublithostatic pressures at greater depths and for caverns with above lithostatic pressures in general. Also standard salt strength determination on jacketed triaxial samples may not be directly applicab
fluids will penetrate into salts. The above theory is supported by laboratory tests and field evidence; for example, unjacketed triaxial tests have been conducted on halite, which showed that the strength measured this way does not exceed the UCS value of approximately 300 ba
Cavern tests are routinely conducted to prove the integrity of solution wells and storage caverns. Because cavern tests are performed as demonstrations, test data are not fully analyzed and information that would be useful in characterizing the well and surrounding salt is ignor
surveys are routinely performed over mining operations and cavern storage facilities because of regulatory requirements. The information from these surveys is often plotted and used to demonstrate that 'normal' subsidence is occurring without recourse to understanding what t
numerical models are described that aid the interpretation of cavern test data and surface subsidence measurements. The theoretical basis, construction, and practical application of each numerical tool is discussed.
The cavern test model is used to interpret shut in and flow-rate cavern test data based on the cavern geometry, temperature and density log information, brine or gas properties, and salt modulus and creep properties. Alternatively, the cavern model can be used to estimate salt
test data. The cavern model is demonstrated for case history test data from storage wells in domal salt and shaft closure in bedded salt.
The surface subsidence model is used to interpret and predict surface subsidence and subsurface strains, which result from underground excavation and creep of salt. The model accounts for the three-dimensional geometry of underground caverns or mined rooms, the timewis
Rock salt in its natural state is typically considered impermeable (k=10-24 m²). Creation of openings in salt, which is initially under lithostatic stress conditions, causes deviatoric stress states and creep begins to occur. There is no strong evidence to suggest that the permeabilit
most situations. An increase in test specimen volume has, however, been observed to occur in some laboratory tests on salt core. Such a volume increase is called dilatancy and is attributed to microcracking occurring both during load application through plastic deformation and
held constant. The microcracking will cause an increase in permeability by increasing the connected porosity. In this paper the stress conditions applied in laboratory tests are separated into those that did and those that did not cause dfiatancy. The types of tests considered are
quasistatic true-triaxial. The laboratory test data are from published test results.
Until recently, little research was done in terms of relating stress states, creep rates, and accumulated strain to damage in rock salt. After reviewing the results of three different laboratory testing programs, a criterion is proposed that signifies the potential for dilatancy based on




                                                                                                                                Page 27
                                                                                                                              SMRIBIBL




Novomoskovsk rock salt deposit is the monobed ore body of gently sloping occurrence, 40-50 m in thickness, situated at 900 m depth.
This deposit is being developed from 1960 by "Azot" (Nitrogen) - a largest in Russia chemical Novomoskovsk Stock Company.
Method for deposit development is the underground salt dissolution with individual caverns by stepwise method and with hydrocarbon blanket liquid.
Due to geological peculiarities and some errors in technology of mining, by early 1990s at the brine field operations occurred crosscutting of a part of caverns between themselves, which resulted, in its turn, to caving of oversalt rocks, ruptures and pinchings of casing and opera
Emergency situation that occurred at the site of crosscut caverns made impossible further operation of these caverns and resulted in drastic drop of the brine field facilities designed capacity. The critical situation urged the Novomoskovsk Stock Company "Azot" to apply to VNIIG
assistance in restoring the needed capacity of brine mining.
The salt mine burial of fission waste products resulting from the reprocessing of spent fuel elements is now planned as a permanent means of disposal of these highly radioactive wastes. Although salt mine burial is apparently the best method of disposal the vigorous self-heatin
some potential problems. Natural salt formations regularly contain small brine inclusions which will migrate up the thermal gradients generated by the self-heating of the waste products. The resulting inflow of water into the nuclear waste crypts is undesirable because water vap
corrosion and/or lead to fission product contamination of currently unused sections of the salt mine. In addition, contaminated vapor-liquid biphase droplets generated on the walls of the nuclear waste crypt are capable of dispersing fission products throughout the saltformation
down thermal gradients, in contrast to the normal thermomigration ofsimple gas or liquid droplets up thermal gradients in salt. By considering viscous gas flow, vapor diffusion, liquid diffusion, evaporation and condensation, and liquid currents driven by surface tension gradients
the vapor-liquid droplets observed in the present investigation is explained. It is concluded that a modest dispersal of radioactive wastes may occur in the saltformation. However, because of droplet trapping by the grain boundaries in the salt, the escape of radioactivity to the ou
The Ruhrgas AG gas storage field Krummhörn is located near the North Sea harbour town of Emden, NW Germany. The present storage facility consists of 3 caverns leached in the Groothusen saltdome (Zechstein 2) at a depth between 1500 and 1800 meters. To investigate t
respect to a future increase of the storage capacity, 2 deep boreholes were drilled in 1994. In one of the boreholes, Krummhörn K 6, an extensive hydraulic fracturing test program was conducted for determination of the in situ stress within the salt at depth, as the limiting input p
storage pressure planning.

Using the MeSy wireline hydrofracturing technique where the double straddle packer unit is moved within the borehole on a standard borehole logging cable, a total of 11 hydrofrac tests were successfully carded out in the 8.5 inch diameter open hole between app. 1300 and 18
initial fracturing cycle and several subsequent refrac cycles for reliable and precise determination of the shut-in pressure. Most of the frac cycles demonstrated distinct breakdown at fracture initiation and reproducible fracture re-opening pressure values, while determination of r
required an extensive analysis of the pressure records. The analysis yields a welldocumented shut-in pressure profile

Psi, MPa = 29.38 + 0.0194 . (z, m - 1300)
or a shut-in pressure gradient of
dPsi / dz, MPa 1 m = 0.0221

for the depth between 1300 and 1720 m (TVD). The shut-in pressure profile is in good agreement with the vertical stress profile derived from various geophysical logs for the overburden density.
Solution mining for salt in Ohio began in 1889. Since 1889, at least 234 solution mining wells have been drilled in Ohio at nine different solution mining facilities. Today, only two projects and 38 wells remain in operation.
The principal salt beds solution mined in Ohio occur within the Silurian-aged Salina Group and include the B, D, E, F,, and F, salt units. Depths to these salt beds range from 1800 to 3150 feet below the surface and individual bed thickness rarely exceeds 100 feet. A number of
been utilized in Ohio since 1889,.but today most wells are operated as two-well galleries that are either hydraulically fractured or directionally drilled to achieve interconnection.
In July of 1989, the Ohio Division of oil and Gas (Division) initiated a study of Class III salt solution mining operations in Ohio to determine whether current practices and regulations were adequate to ensure protection of Underground Sources of Drinking Water (USDWs) . This
solution mining projects; two of which are currently active, and three which were abandoned.
During this project, the Division investigated 90 oil and gas wells near the five solution mining facilities to determine the possible extent of the solution mining caverns and whether the uncemented surface/production casing annuli of these wells could pro,yide potential avenues
into USDWs. Special permit conditions for drilling, completion, and plugging of oil and gas wells have been developed and implemented as a result of this study. Review areas have been delineated around all five facilities. If an application for permit to drill or plug is received fo
the Division performs a site specific review and designs special permit conditions for protection of USDWs.
One of the principal areas of concern investigated during this study was the abandoned PPG Industries, Inc. solution mining facility at Barberton, Ohio. Oil and gas drillers have reported encountering fluids with unusual pressures, volumes, and properties and/or gases while dri
Group interval. In addition, the Division found that plugged solution mining wells were leaking fluids to the surface. The Division of oil and Gas and the Ohio EPA sampled 15 oil and gas wells that may have penetrated the Salina Group and two leaking solution mining wells in an
Attempts to effect permanent disposal of radioactive wastes in marine evaporates should do nothing to disturb, either in the short or the long term, the present relative stability of such bodies of rock. It is necessary to take account of all of the geochemical and physico-chemical
in the processes which formed the evaporates before proceeding to an acceptable strategy for disposal of radionucleldes.
These processes can be represented as three kinds of metamorphism: 1. solution metamorphism, 2. thermal metamorphism, 3. dynamic metamorphism. In all of the evaporate occurrences in Germany such processes have been influential in altering, on occasion significantly, th
and have also promoted a considerable degree of transposition of material.
Given similar geochemical and physico-chemical premises, these metamorphic processes could become effective now or in the future. It is therefore necessary to discuss the following criteria when examining salt domes as permanent repositories of highly radioactive substance

(1) Temperatures90° ± 10°C at the contact between waste containers and rock salt;
(2) Temperatures75°C within zones of carnallite rocks;
(3)Immobilisation of high-level waste in crystalline forms whenever possible;
(4)Systems of additional safety barriers around the waste containers or the unreprocessed spent fuel elements. The geochemical and physical effectiveness of the barriers within an evaporate environment must be guaranteed. For example: Ni-Ti-alloys, corundum, ceramic, anh
Hydraulic fracturing stress measurements were made in five different salt strata of the Permian-Age Paradox Formation (Nelson, et al., 1982, and Schnapp, et al., 1983). Test depths ranged from 3130 to 4890 ft.
The measurements were made in the Gibson Dome No. 1 (GD-1) borehole in southeastern Utah. Sedimentary Permian- and Pennsylvanian-Age deposits of sandstone, siltstone, limestone, and dolomite overlie the Paradox Formation to a depth of 2618 ft. The Paradox Formatio
separated by interbed sequences of anhydrite, dolomite, and fine clastic rock. The Paradox Formation was deposited in 29 depositional cycles with a total thickness of 2890 ft in the GD-1 borehole.
The salt found in each cycle is generally 95 percent pure and forms beds from 7 to 346 ft thick. Anhydrite bands within the salt beds comprise 2 to 5 percent of the rock mass in each depositional cycle. The anhydrite is found in two forms: (1) laminar anhydrite, which forms band
and spaced 1 to 4 in. apart; and (2) diffuse 1-in.-thick bands of anhydrite sand in a salt matrix. The anhydrite does not cause planes of weakness within the individual salt strata.
Care was taken to choose hydraulic fracture test intervals. that were (1) totally within a single cycle of salt, and (2) unfractured. To confirm an unfractured interval within the salt cycle, the core was carefully examined for preexisting fractures. None was observed within the test z
This is a report on field tests performed for the SMRI project, "Hydrofracture Gradients In Salt Domes". This project was initiated in May, 1984, with an initial time period of one year. The time period subsequently was extended for a second year.
Some preliminary hydraulic fracturing field test results for the Rayburns Dome were presented at the Fall SMRI meeting in October, 1985. Additional test data obtained in late December, 1985, are presented here, along with an interpretation of their significance.
This project has not been completed because of a significant set back experienced on a "final" field test series in March, 1986. The downhole valves/ controls chamber was flooded, and a number of test equipment components subsequently were damaged to an extent that will r
another 3 to 4 months are needed to complete this study.
Our current plans are to rebuild the valves/controls downhole assembly to essentially the same configuration as the predecessor unit, since the predecessor functioned downhole in a very satisfactory way prior to flooding. Moreover, a series of "checks" will be incorproated into
avoid any possible future flooding mishaps. We anticipate completing the field test program without additional significant delays once the rebuilt valves/ controls unit and incorporated procedure/equipment "checks" are ready.




                                                                                                                               Page 28
                                                                                                                               SMRIBIBL




The plugging and abandonment of caverns and the cementing of a liner into a leaking wellbore have the same critical first step: how to establish the first plug to work against. This paper will discuss five methods that are being used, these are:
1) Inflatable Packer
2) Umbrellas or oversized cement baskets
3) Section Milling and inflatable packers
4) Lightweight Cement using perlite additives
5) Foamed Lightweight Cements
The success and the cost effectiveness of each method is dependent upon the borehole geometry, and these considerations will also be discussed.
Results of laboratory tests, field tests and field observation of salt characteristics pertinent to either the storage of hydrocarbons or the disposal of industrial wastes are given. Of particular significance is the indication that under many conditions dry salt may be sufficiently perme
aqueous fluids. This flow appears to occur along crystal boundaries and cleavage planes and through bands of impurities, including dehydrated shales or mudstones. Present data indicate that water, even in very small quantities, materially affects these characteristics.
The variation and the presence or absence of permeability appear to be a function of (1) the type and amount of impurities (including shale), (2) the crystalline structure and cleavage planes, (c) the confining or overburden pressure and (4) water content. Additional study of thes
accurate evaluation of the feasibility of storage or disposal under various conditions can be made. The amount and effect of moisture content are particularly important, and additional study of both the amount and effect of in situ moisture is needed.

The velocities of elastic waves and the thermal conductivity of rocksalt -measured both in situ as well as in the laboratory - were compared with the corresponding values calculated theoretically. The basis of these theoretical values are the elastic and thermal data of NaCl cryst
The comparison shows that an undisturbed salt deposit has the same properties as those of quasiisotropic crystalline NaCl which is free from voids. Rocksalt, in situ around cavities in the mine and in the form of specimens, must have a looser structure on account of different el
Experiments with air under high pressure in salt mines have proven the impermeability of the salt rocks. Bituminous material in salt formations is usually of syngenetic origin. Its presence does not indicate a migration into the salt. C02 gas under high pressure occurs in the salt o
consequence of Tertiary volcanism. This gas could not escape since that time because of the impermeability of the salt.
This paper provides an overview of the current level of understanding of the creep behaviour of natural rock salt on the basis of physical processes and practical experience. Transient as well as stationary creep were defined on the basis of the effective deformation mechanism
discussed for both cases. This revealed that the reliable prediction of deformation over long periods of time is only possible on the basis of physical theories.
The correct modelling of the stress sensitivity of the creep is particularly important. Although this has not yet been solved satisfactorily, a stress exponent of n = 5 to 7 in the median stress zone is applicable. The use of a precise law for the stationary creep of a specific rock salt
together with a law for transient creep. Transient behaviour can only be adequately modelled with the help of inner strength variables. In addition, problems are discussed which arise when extrapolating one dimensional laws to three dimensional space.
The major differences in creep behaviour of various rock salt types are presented and attributed to the effect of contamination - the distribution of which has a geological cause. An example is the frequently observed difference in behaviour of rock salt from the Staßfurt series (z
exploration methods allow homogeneous zones with the same mechanical behaviour to be determined in rock salt deposits. The increasing effect of humidity on creep in the vicinity of cavities is quantitatively described on the basis of laboratory tests. Moreover, the effect of dila
Deep exploration wells have penetrated the salt series in the margins of the basin where it reaches a maximum thickness of 3000 to 3500 m (Biikshal, Kenkijak, Kindyssai, and other salt domes). In the centre of the basin it has been partially penetrated up to 2000 to 2500 m o
Tschernaja Retschaka, etc.).
A review of the state-of-the-art of the hydrofrac technique as applied to solution mining - being a method for obtaining a viable connection between two wells in a salt bed while enjoying the advantages of minimum cost and time. Directed to describing the mechanism and applica
terminology and identifying unknowns and areas open to research and further study.
The fluids in salt have been used as sources of information on the geological events leading to the formation of the enclosing salt beds, and the subsequent changes to which these beds have been exposed. In recent years, however, consideration of salt beds or domes as poss
repositories has added new significance to the study of such fluids.
This paper reviews the current status of the study of the types of fluid present in salt, their origin and evolution, and their significance to understanding the geological processes that have occurred.. These studies are pertinent to the engineering design of a nuclear waste storag
might happen in the future. The fluids in salt also introduce problems in the engineering design of a safe nuclear waste installation that must be carefully evaluated at each suggested site.

For the design and layout of gas storage caverns in salt rock it is necessary to develop a new criterion to determine the permissible maximum internal cavern pressure. The present concepts for determination of the maximum allowable internal pressure do not sufficiently consid
rock material, the history of internal cavern pressure and due to the loading conditions the induced secondary permeability of the rock salt.
Numerous laboratory research studies on the secondary permeability of rock salt have been published within recent years. The results of these studies will have to be integrated in the development of the new assessment criterion. Another main item to be included will be the tim
rock salt in loading and unloading conditions.
The paper points out by the way of example the influence of some significant parameters for the determination of the maximum permissible cavern pressure. It will be shown what kind of improvement is necessary to get a more accurate estimation for the safety against the loss
The influence of depth on porosity was investigated using rock salt as an example. This first involved eliminating the effect of the three main contaminants: sylvine, kieserite and anhydrite. This resulted in the unexpected observation that each contaminant salt independently gen
porosity in the rock salt with increasing content of the contaminant salt. This is attributed to the periodically changing binding strength of the rock salt lattice. No depth influence on porosity was determined.
Permeabilities lower than 10-17 m² cannot be measured using classical methods. To overcome this problem, the pulse decay method may be applied. In this method the evolution of a pressure pulse applied on the upstream side of the sample at t = 0 is recorded. An apparatus
low permeabilities of rocks under thermomechanical stresses; intrinsic permeabilities between 10-15 and 10-22 m2 can be measured.
Several thermo-mechanical tests, including permeability determinations have been carried out on samples from saline lithofacies of the Bresse basin (France). The initial permeabilities are more representative of the condition of the test sample than of the undisturbed state of th
permeability changes observed during these tests seem to be directly connected to the nature and structure of the material and are indicative of the structural modifications the material sustains under changes of temperature and stress. During isotropic deformation tests, the re
varies depending on the specific lithological characteristics of the samples. Deformation tests under deviatoric stress with constant confining pressure and temperature show that, for all the lithofacies, the permeability decreases continuously. This can be attributed to creep defo
WIPP Salado Hydrology Program Data Report #l presents hydrologic data collected during permeability tests of the Salado Formation performed from August 1988 through December 1989. Analysis and interpretation of the test data are presented in a separate report. The repo
and testing of six boreholes drilled from the WIPP underground facility 655 m below ground surface in the Salado Formation. Permeability tests were conducted using multipacker test tools with inflatable packers to isolate borehole intervals to allow formation pore-pressure build
tests. Test data include pressures and temperatures in brine-filled, packer-isolated test intervals and borehole-closure and axial test-tooi-movement measurements. The test boreholes are 4.0-inch (10.2 cm) in diameter, and were cored in halite and associated anhydrite interbed
oriented vertically downward, angled downward, and horizontal. The boreholes were drilled and cored using compressed air to remove drill cuttings. Three boreholes were drilled in Room C2: C2H01, C2H02, and C2H03. Borehole C2H01 was initially drilled to a depth of 5.68 m
deepened to 8.97 m to include Marker Bed 139 in the test interval. Borehole C2H02 was drilled to a depth of 10.86 m (7.68 m vertical projection from the floor of Room C2) at a 45° downward angle from the junction of the west wall and floor of Room C2. Marker Bed 139 was in
C2H02. Borehole C2H03 was drilled horizontally into the west wall of Room C2. Vertically downward boreholes were drilled from the floor in the North 1420 drift (borehole N4P50); the South 1300 drift (borehole SOP01); and in Room 7, Waste Panel 1 in the waste-storage area
Permeability tests were performed after installing multipacker test tools in test boreholes, inflating the packers, and allowing pressures to build up in the isolated intervals. Pulse-withdrawal tests were performed after buildup pressures approached the apparent formation pore p
Five in situ permeability measurements have been performed and evaluated based on the assumption of an unsaturated homogeneous formation using a program for the computation of one-dimensional pressure fields.
A partly good agreement between measured and calculated pressure curves was achieved, although in some cases a temperature reduction would have been required.
The calculated permeabilities were all in the range of 10-9 Darcy.
Elastoplastic short term behaviour and damage mechanisms of rocksalt are studied experimentally and theoretically. Review of previous works on rocksalt deformation mechanisms shows the role of different physical factors on ductile or brittle behaviour of rocksalt. Mechanical
those of other geomaterials. Experimental methods for identification of geomaterial damage are reviewed.
Compression and extension axisymmetric triaxial tests are performed. Volume change measurements are carried out during the tests. Under deviatoric loading, volumetric strain denotes the material damage state, especially damage initiation. Variation of elastic parameters is a
into account in the constitutive law.
A simple analysis of internal stresses using a self-consistent model allows to explain that damage appears earlier under extension loading than under compression. Kinematic and isotropic hardenings are then discussed.
An elastic-plastic model is proposed. It considers isotropic hardening and non associated flow rule with plastic distortion as a hardening parameter. Model parameters are fitted on the basis of experimental results related to the evolution of dilatancy angle. A 3D generalisation (u
is proposed. The constitutive model takes into account behaviour difference between extension and compression loadings. An application to circular cavities is given.




                                                                                                                                Page 29
                                                                                                                                SMRIBIBL




By studying the influence of atmospheric conditions on the rheological properties of rocks, we can find out more about their deformation and can study the process of fracture in nearly narural conditions.
Renzhiglov [l] investigated the influence of moisture in rocks (argillaceous and arenaceous) on their rheological properties. He found that moisture activates their creep. Surfactants strongly alter the mechanical properties of materials [2]. The surfactant may be simply a damp at
atmospheric moisture weakens the elementary interatomic bonds, so that creep becomes more rapid. Many investigations have revealed that it is elementary mechanisms of interatomic bond rupture which are responsible for processes occurring during long-term tests.
In this article we give a comparative assessment of the results of rests on the long-term strength of potassium salts (from the Verkhnekamskaya potash deposit) and rock salt (from the Starobin potash deposit), when atmospheric moisture was affecting their properties. The rest
Beginning with a state of the art review on criteria for the evaluation of safety at maximum internal cavern pressure state for gas storage caverns in domal rock salt designed for seasonal storage, a new criterion has been developed. It evaluates safety on the basis of a boundary
state is equated to that point in time when the infiltration of the storage medium into the rock mass starts and can not be prevented from continuing.
This is defined by a combined infiltration / safety criterion, describing the onset of infiltration qualitatively if the internal cavern pressure exceeds the level of one of the two components of the local stress state acting perpendicular to the spreading direction of the infiltration proce
infiltration being normal to the cavern wall in the vicinity of the cavern. The quantitative measure is given by the minimum extent of a closed safety zone surrounding the cavern where the two stress components of the local stress state in the rock mass, which are acting perpend
secondary induced infiltration, exceed the internal cavern pressure by a certain level.
Carrying out a sensitivity study including the main influencing factors on the rock mass state at maximum internal cavern pressure reveals that the developed criterion works, giving a qualitative and quantitative measure for the specific state to evaluate.
From that study it can be stated that the main influences on safety at maximum internal cavern pressure are associated with initial conditions such as the primary stress state (densities of the overlying rocks, depth of the cavern), the geometrical layout parameters (shape of cav
between cavern roof and casing shoe) and site location factors (pillar width).
The operating history conditions assuming a typical seasonal storage have a medium (time period at preceding minimum internal cavern pressure) to small (minimum pressure level) and very small (pressure drop down rate, level of preceding operations) effect on safety at maxi
Provided the material parameters for a suitable material law describing the response of rock salt under loading and unloading are determined with adequate accuracy, the studied influencing factors depending on material behavior have very small influence on the stress state in
cavern pressure (comparison of different material laws). But if the assumed set of material parameters is not representative, the change in safety conditions will be apparent in the sense of a declined or even non-existent safety zone (s. variation of material quality). Creep respo
influence on safety at maximum internal cavern pressure state.




                                                                                                                                 Page 30
                                                         SMRIBIBL




Descriptors                                    Remarks

In-situ tests                                  -




Interdependence rock stresses - permeability   -


Pore pressure in permeable salt /
high deviatoric stress;
Reservoir Mechanics                            -


In-situ tests                                  -

Cavern abandonment;
Thermodynamics                                 -




In-situ tests;
Thermodynamics;
Rock Mechanics                                 -




In-situ tests;
Thermodynamics                                 -


Permeability of rock salt                      -




Cavern abandonment                             -


Permeability of rock salt                      -

Permeability of rock salt                      -


Hydrofracturing                                -

Cavern abandonment;
Borehole seal;
Rock mechanics                                 -




In-situ tests                                  -




Hydrofracturing                                -




                                                         Page 31
                                                        SMRIBIBL




In-situ tests;
Permeability - liquid pressure above confining
pressure;
Reservoir Mechanics                                 -
Permeability of rock salt;
Hydrofracturing;
Reservoir Mechanics                                 -


Cavern abandonment;
Thermodynamics;
Creep behavior                                      -




Borehole seal                                       -




Borehole seal;
In-situ tests                                       -




Creep behavior;
Interdependence rock stress - permeability;
Permeability - liquid pressure above confining p;
Reservoir Mechanics                                 -




Creep behavior                                      -
Permeability of rock salt;
Interdependence rock stress - permeability;
Hydrofracturing                                     -

Borehole seal                                       -


Pore pressure in permeable salt;
Reservoir Mechanics                                 -




In-situ tests;
Permeability - liquid pressure above confining
pressure;
Reservoir Mechanics                                 -




                                                        Page 32
                                                                     SMRIBIBL




Permeability of rock salt                            -




Creep behavior                                       -




Creep behavior                                       -

In-situ tests;
Permeability of rock salt;
Reservoir Mechanics;
Pore pressure                                        -
Borehole seal;
Cavern abandonment                                   -

Rock mechanics;
Permeability of rock salt                            -
Cavern abandonment;
Permeability - liquid pressure above confining
pressure;
Reservoir Mechanics                                  -


Hydrofracturing                                      -




Interdependence rock stress - permeability;
Permeability of rock salt - High deviatoric stress   -




Cavern abandonment                                   -

Cavern abandonment;
Rock mechanics                                       -




Cavern abandonment;
Borehole seal                                        only abstract




                                                                     Page 33
                                                                     SMRIBIBL




Permeability of rock salt    -




Creep behavior               -




Hydrofracturing              -


Creep behavior               -




Cavern abandonment;
Rock mechanics               only Abstract; German original at KBB




Permeability of rock salt;
Reservoir Mechanics          -




Permeability of rock salt    -




Creep behavior               -


Permeability of rock salt    -




                                                                     Page 34
                                                         SMRIBIBL




Interdependence rock stress - permeability;
Permeability of rock salt - High deviatoric stress   -




Interdependence rock stress - permeability;
Permeability of rock salt - High deviatoric stress   -

Borehole seal                                        -




Permeability of rock salt;
Pore pressure in permeable salt;
Reservoir Mechanics                                  -




Interdependence rock stress - permeability           -


Borehole seal                                        -




                                                         Page 35
                                                                                   SMRIBIBL




Permeability of rock salt;
Interdependence rock stress - permeability           -




Creep behavior                                       -




Creep behavior                                       only abstract; out of print




Borehole seal                                        -




Permeability of rock salt - High deviatoric stress   -




Permeability of rock salt;                           thesis separately;
Interdependence rock stress - permeability           (1 copy for SMRI)




Permeability of rock salt                            -




Permeability of rock salt - High deviatoric stress   -


Borehole seal                                        -




Permeability of rock salt                            -


Permeability of rock salt - High deviatoric stress   -


Permeability of rock salt                            -


Permeability of rock salt                            -




                                                                                   Page 36
                                                  SMRIBIBL




Permeability of rock salt;
In-situ tests                                 -

Hydrofracturing                               -




Rock mechanics                                -




Creep behavior                                -




Interdependence rock stress - permeability;
Creep behavior                                -




Miscellaneous                                 -




Creep behavior                                -




                                                  Page 37
                                                                                        SMRIBIBL




Rock mechanics                                  only abstract


Cavern abandonment                              -
Pore pressure;
Permeability of rock salt                       -




Hydrofracturing                                 -




Cavern abandonment                              -




Permeability of rock salt;
Reservoir Mechanics                             -


Rock mechanics;
Cavern abandonment                              -




Hydrofracturing                                 only abstract; German original at KBB


Borehole seal                                   -

Creep behavior                                  -


Borehole seal                                   -

Interdependence rock stresses - permeability;
High deviatoric stress                          -




Creep behavior                                  -




Interdependence rock stresses - permeability;
High deviatoric stress;
Pore pressure in permeable salt                 only abstract; German original at KBB




                                                                                        Page 38
                                                                       SMRIBIBL




Interdependence rock stress - permeability   -

Interdependence rock stress - permeability   -




Creep behavior                               -




Cavern abandonment;
Rock mechanics                               -


Creep behavior                               -

Interdependence rock stress - permeability   no abstract




Creep behavior - phenomenological approach   -




Creep behavior - phenomenological approach   -




Creep behavior                               -


Hydrofracturing                              -

Permeability of rock salt                    -
Cavern abandonment;
Thermodynamics                               -

Rock mechanics;
Permeability - High devitoric stress;
Interdependence rock stress - permeability   only abstract, in press




Pore pressure;
Permeability of rock salt;
Reservoir Mechanics                          only abstract, in press




                                                                       Page 39
                                                                                      SMRIBIBL




Pore pressure;
Permeability of rock salt;
Reservoir Mechanics;
Interdependence rock stress - permeability    in press




Interdependence rock stress - permeability;
Permeability of rock salt;
Reservoir Mechanics                           -


Creep behavior                                -




Hydrofracturing                               -




Interdependence rock stress - permeability;
Rock mechanics                                only abstract; German original at KBB

Rock mechanics                                -


Creep behavior                                -




Permeability of rock salt                     -




Rock mechanics;
Permeability - High deviatoric stress;
Interdependence rock stress - permeability;   French thesis separately;
Reservoir                                     (1 copy for SMRI)


Permeability of rock salt                     -




Creep behavior                                -


Borehole seal                                 -




                                                                                      Page 40
                                                                     SMRIBIBL




Interdependence rock stress - permeability;
Permeability of rock salt - High deviatoric stress   -




Creep behavior                                       -


Cavern abandonment;
Rock mechanics                                       -


Hydrofracturing                                      -




Borehole seal;
Cavern abandonment                                   -
-                                                    no abstract

In-situ tests                                        only Abstract




Permeability of rock salt                            -




Hydrofracturing                                      -




Cavern abandonment;
Borehole seal;
Interdependence rock stress - permeability;
Reservoir Mechanics                                  -




                                                                     Page 41
                                                                                              SMRIBIBL




Permeability of rock salt;
Reservoir                                             only abstract; German original at KBB




Creep behavior                                        -


Permeability - High deviatoric stress                 -




Interdependence rock stress - permeability;
Strength of rock salt in case of brine impregnation   -


Creep behavior;
Interdependence rock stress - permeability            -


Interdependence rock stress - permeability;
Permeability - High deviatoric stress;
Perm. - Liquid pressure above confining pressure      -




In-situ tests;
Rock mechanics                                        -




Interdependence rock stress - permeability            -




                                                                                              Page 42
                                SMRIBIBL




Hydrofracturing             -




Permeability of rock salt   -




Hydrofracturing             -




Cavern abandonment          -




Permeability of rock salt   -




Hydrofracturing             -




Hydrofracturing             -




                                Page 43
                                                                          SMRIBIBL




Borehole seal                                 -




Permeability of rock salt                     -




Permeability of rock salt;
Pore pressure in permeable salt               -




Creep behavior                                -

Permeability of rock salt                     -

Hydrofracturing                               -




Permeability of rock salt                     -




Interdependence rock stress - permeability;
Rock mechanics                                -

Miscellaneous                                 -




Permeability of rock salt;
Interdependence rock stress - permeability    -




Permeability of rock salt                     only extracts


Permeability of rock salt                     -




                                              French thesis separately;
Rock mechanics                                (1 copy for SMRI)




                                                                          Page 44
                                                  SMRIBIBL




Rock mechanics;
Creep behavior                                -




Interdependence rock stress - permeability;
Rock mechanics                                -




                                                  Page 45

								
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