Aqueous Geochemistry

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					Eleventh Annual V. M. Goldschmidt Conference (2001)                                                                              sess87.pdf

                                                   POSTER PRESENTATIONS
                                               Colonnade Room and Stratford Atrium

                                                        Aqueous Geochemistry

           Savenko A. V.
               The Influence of Magnesium Upon the Sedimentation of Calcium Phosphates in Heterogeneous System CaCO3–
               Seawater [#3180]
               Interaction of calcium phosphates with seawater was experimentally studied. It is proved that carbonates’
               exchange by the apatites takes place inside the sediments layer in case of increased concentration of dissolved
               phosphates in porous solutions.

           Golubev S. V. Savenko A. V. Baturin G. N.
               Solubility of Crandallite in Seawater [#3181]
               Solubility of crandallite in seawater was experimentally studied. It is proved that aluminum phosphates may be
               a source of dissolved phosphorus which might later take part in genesis of sea phosphorites.

           Kalinichev A. G. Kirkpatrick R. J.
               H2O-NaCl Fluids: Thermodynamics, Structure, Ionic Hydration and Hydrogen Bonding as a Function of
               Temperature, Pressure, and Concentration [#3291]
               MD computer simulations were performed at temperatures, pressures, and concentrations up to 773 K, 1000
               MPa, and 4.4 m to study the energetic and structural details of the H-bonded networks and the ionic hydration
               shells in H2O-NaCl solutions.

           Putnis C. Pina C. M. Pollok K. Glikin A.
               Mineral Replacement Reactions in Solid Solution-Aqueous Solution Systems [#3555]
               The system KBr-KCl is used as a model replacement reaction. AFM observations combined with SEM and
               microprobe analyses show the replacement is by dissolution and reprecipitation — the rate of replacement is
               strongly dependent on supersaturation.

           Schofield P. F. Bailey E. H. Mosselmans J. F. W.
               Uranium(VI)-Citrate Speciation — pH and Temperature Dependence [#3602]
               In situ X-ray Absorption Spectroscopy has been used to investigate the pH and temperature dependence of the
               speciation of the uranyl ion in the presence of citrate ligands.

           Wilson C. L. Hinman N. W.
               Changing Water Chemistry in Thermal Springs May Affect Metal and Hydrogen Peroxide Cycling [#3713]
               Recent changes in the water chemistry of the Roadside Springs in Yellowstone National Park may affect metal
               redox cycling, metal availability, hydrogen peroxide formation and degradation, and the photochemistry of the

           Dolin V. V. Bondarenko G. N. Samchuk A. I. Kononenko L. V. Sushchyk Yu. Ya. Shramenko I. F.
           Dudar T. V.
               Geochemical Approach to the Problem of Restoration of Radiation Contaminated Areas [#3022]
               Conception of self-restoration and its geochemical criteria have been worked out. An effective resource of
               decreasing of radionuclides and heavy metals accumulation by vegetation on zeolite basis has been worked out
               and tested in natural conditions.

           Maurice P. A. Drummond J. Cabaniss S. E.
              Hydrologic and Geochemical Controls on the Chemical Characteristics of Natural Organic Matter at a Small
              Freshwater Wetland [#3072]
              Hydrologic and geochemical techniques were combined to study the hydrogeochemical controls on the
              chemical characteristics of natural organic matter in a small stream in the New Jersey Pine Barrens.
Eleventh Annual V. M. Goldschmidt Conference (2001)                                                                                sess87.pdf

           Ford S. T. Leithold E. L. Blair N. E.
               Transformations of Organic Matter Associated with Clay Sized Particles on a Transect Across the Northern
               California Continental Margin [#3168]
               Most organic carbon burial occurs on continental margins, where sediments discharged by rivers accumulate.
               The Eel River system illustrates the transformations of organic matter en route from river sources to burial on
               the continental margin.

           Gu B. Chen J.
               Microbial Reduction of Contaminant Metals as Affected by Different Fractions of Natural Organic Matter
               Different fractions of natural organic matter were isolated and characterized for their structural and functional
               properties. These properties were found to be important in mediating microbial reduction of contaminant

           Tang J. Johannesson K. H.
              Speciation of Rare Earth Elements in Natural Waters: Assessing the Role of Dissolved Organic Matter [#3418]
              A humic ion-binding model was used to assess the role of dissolved organic matter in REE speciation. Several
              natural waters exhibiting wide ranges of pH, ionic strength, and DOC concentrations were selected to examine
              humate-REE interactions.

           McGrath C. J.
              Abiotic and Microbially-mediated Reactions Affecting Explosives (TNT, RDX) in Reduced Iron Systems [#3868]
              The reactions of explosives (TNT, RDX) are examined as a function of temperature, the nature of the reactive
              surface (metallic iron, ferrous minerals, dissolved ferrous iron), and the presence of bacteria.

           Goyne K. W. Chorover J. Brantley S. L. Komarneni S.
              Sorption of 2,4-Dichlorophenoxyacetic Acid to Porous Minerals [#3413]
              Porous and non-porous silica and alumina were reacted with 2,4-D to investigate differences in organic
              compound sorption in the presence/absence of mineral mesopores. Isotherms indicate that porous alumina
              sorbed more 2,4-D than non-porous alumina.

           Hou X. Kirkpatrick R. J.
              Nucleotide Phosphate-layered Double Hydroxides (LDH) Nano-Composites [#3355]
              Adenosine-5’-monophosphate (AMP, a hydrolysis product of adenosine triphosphate, ATP) readily exchanges
              into the interlayers of LiAl2 LDH, and we report here a study of the stability and structure of this nano-hybrid.

           Zimmerman A. R. Brantley S. L. Kubicki J. D. Chorover J. Goyne K. W.
              The Effect of Mesopores on Organic Adsorption to Mineral Analogues [#3565]
              We conducted amino acid adsorption experiments using synthetic aluminosilicate mineral analogues with
              defined mesopore sizes to examine the hypothesis that organic matter is protected from degradation by
              occlusion in mineral mesopores.

           Vasudevan D. Fimmen R. L. Francisco A. B.
               Influence of Compound 3-D Structure on Adsorption at the Mineral-Water Interface [#3851]
               This research is aimed at determining the molecular structures of the isomers of Rhodamine WT (a fluorescent
               water tracer) and examining the role of isomer 3-D structure on the nature and extent of adsorption onto mineral

           Zhang Z. Zhang B.
              Environmental Geochemistry of the Lanmuchang Tl Deposit [#3365]
              Lanmuchang is the only large-size independent Tl deposit in the world. Samples of plant and villagers’ urine as
              well as hair and nails from the Tl mining district were analyzed. Analytical results showed that the contents of
              Tl, Hg and As are high.
Eleventh Annual V. M. Goldschmidt Conference (2001)                                                                            sess87.pdf

           Huang W. Lerner D. N. Smith C. C. Thornton S. F.
              A Novel Method to Investigate the Mixing Processes of Dissolved Oxygen and a Plume in Porous Media
              A novel non-invasive imaging technique was developed to investigate the mixing process of dissolved oxygen
              and plume in a two-dimensional porous media at laboratory.

           Lamb W. M. McShane C. J. Popp R. K.
              Phase Relations in the CH4-H2O-NaCl System: Comparison of Experiments and Equations of State [#3284]
              Synthetic fluid inclusions were used to determine the extent of immiscibility and compositions of co-existing
              fluids in the CH4+H2O+NaCl system. Results indicate good agreement between experiment and existing
              equations of state.

           Shiota D. Nakashima S.
               The Kinetic Effects of Silica on the Transformation of Amino Acids [#3489]
               A new hypothesis of coupled dehydration-polymerization in the hydrous silica-amino acids systems for the first
               chemical evolution of life was tested by some experiments. The polymerization reaction was kinetically favored
               by the presence of silica.

           Fu Q. Seyfried W. E. Jr.
               Hydrothermal Reduction of Carbon Dioxide Using Magnetite [#3581]
               With magnetite as a catalyst under hydrothermal conditions, CO2 reduction processes were observed. CH4 and
               CO were detected. A hypothesis, analogous to the F-T synthesis, is proposed. Within the whole process, the
               surface of magnetite is the key.

           Foustoukos D. I. Allen D. E. Fu Q. Seyfried W. E. Jr.
               Experimental Study of CO2(aq)/CO(aq) Redox Equilibria at Elevated Temperatures and Pressures: The Effect of
               pH on Reaction Relations [#3855]
               Experiments were performed to evaluate CO2(aq) reduction to CO(aq) under subseafloor hydrothermal
               conditions. The results indicate that acidic conditions enhanced CO catalysis. Our observations are in good
               agreement with theoretical predictions.

           Rakovan J. Sutton S. Newville M. Lanzirotti A.
              The Use of WDS in Synchrotron X-Ray Fluorescence and Spectroscopy: Case Studies Involving Heterogeneous
              Reactivity at the Mineral-Water Interface [#3795]
              The use of WDS in Synchrotron XRF and XAS is a powerful tool in the analysis of trace elements in complex
              materials such as minerals. We have been using WDS in studies involving heterogeneous reactivity at the
              Mineral-Water Interface.

           Gray J. C. Vanko D. A. Bodnar R. J. Sutton S. R. Lanzirotti A.
               Synchrotron X-Ray Fluorescence Microprobe Determination of Halides in Natural and Synthetic Aqueous-
               Fluid Inclusions: Analytical Protocol for Low-Salinity Inclusions [#3445]
               Synthetic fluid inclusions in quartz containing known amounts of Cl, I, and Br were excited with synchrotron
               X-ray beams of varying energy and flux. The goal is to develop a protocol for determining Cl/Br in natural low-
               salinity fluid inclusions.

           Kubicki J. D. Heaney P. J.
              Modeling Interactions of Aqueous Silica and Sorbitol: Complexation, Polymerization and Association [#3407]
              Our objectives are to test NMR peak assignments for aqueous solutions of silica and sorbitol, examine possible
              alternative explanations for the observed NMR peaks, and examine mechanisms of silica-sorbitol association in
              aqueous solutions.
Eleventh Annual V. M. Goldschmidt Conference (2001)                                                                                sess87.pdf

           Kalinichev A. G. Wang J. Kirkpatrick R. J.
               Structure of Carbonate and Bicarbonate Aqueous Solutions: Molecular Simulation of Ionic Hydration and Ion
               Pairing [#3293]
               The structure of carbonate solutions is difficult to study experimentally by conventional X-Ray methods
               because C and O of the carbonate species are indistinguishable from O of H2O. Computer simulations are used
               here to overcome these problems.

           Zhang Z. Ding K. Seyfried W. E. Jr.
               Ti(Ti/TiO2)-pH Sensor: An Alternative Method to YSZ-pH Sensor for Measuring pH in Hydrothermal Fluid
               Preliminary experiments demonstrated excellent pH-sensing ability of Ti(Ti/TiO2) material in NaCl-bearing
               fluid from room temperature to 300ºC. The results indicate that Ti-pH sensor can be potentially used as an
               alternative to YSZ-pH sensor.

           Hodson M. E.
              Experimental Evidence for Zr Mobility in Soils [#3266]
              Soil weathering calculations typically assume Zr immobility. This is not the case but Zr mobility is low (2–3
              orders of magnitude < that of major cations) so weathering rate calculations assuming Zr immobility only
              underestimate element release by <5%.

           Nasraoui M. Prudêncio M. I. Waerenborgh J. C.
               Geochemical Discrimination Indexes for Granitic Rocks: Application to Monument Stones [#3353]
               Geochemical study including Mössbauer spectroscopy was undertaken to characterize the stones of Évora
               Cathedral and some surrounding quarries. The samples have consistent geochemical characteristics well
               constrained by a limited number of element.

           Sak P. B. Brantley S. L. Fisher D. M.
               Diffusion Models for Weathering Rind Genesis [#3397]
               The rate of weathering rind growth around andesitic clasts is evaluated using both linear and shrinking core
               diffusion models.

           Petelet-Giraud E. Négrel Ph. Barbier J. Gautier E.
               Surficial and Ground Water Relations in the Loire Catchment (France). An Isotopic Characterization Focuses
               on a Wetland in the Upper Basin [#3222]
               This study, part of a French National Research Program dedicated to wetlands, aims to provide geochemical
               (major and trace elements, H2O stable isotopes and strontium isotopes) constraints on the hydrological
               functioning of the Loire catchment.

           Anderson S. P. Longacre S. A. Anderson R. S. Kraal E. R.
              Patterns of Glacial Water Chemistry and Discharge: Implications for Subglacial Water Storage [#3889]
              Kennicott Glacier shows long period variations in outlet river discharge and river chemistry. We hypothesize
              that these variations reflect changes in water storage underneath the glacier, and can be seen in the chemistry of
              the river.

           Boulanger J. R. Stewart B. W. Lowenstein T. K. Capo R. C.
               Sources of Water and Dissolved Solids in Death Valley: A Strontium Isotope Investigation [#3876]
               Strontium isotope ratios measured from Death Valley spring waters suggest a local source for solutes over the
               past 100 ka.

           Riotte J. Chabaux F. Benedetti M. Dia A. Boulègue J. Gérard M.
               Origin of the 234U-238U Fractionation in Surface Waters of Mount Cameroon [#3614]
               The purpose of this study is to discuss the parameters influencing the 234U-238U fractionation in dissolved load
               of river waters by a study of the hydrological system of Mount Cameroon volcano.
Eleventh Annual V. M. Goldschmidt Conference (2001)                                                                               sess87.pdf

           Dupré B. Dessert C. François L. M. Schott J. Gaillardet J. Allègre C. J.
              Studies of Basaltic Weathering Law and Elements Fluxes to Ocean [#3607]
              This study attemps to propose laws which both characterize the basalt weathering and quantify more precisely
              the elements fluxes from basalt erosion to the oceans.

           Dessert C. Dupré B. François L. M. Schott J. Gaillardet J. Oliva P. Chakrapani G.
               Erosion of Deccan Traps Determined by River Geochemistry. Impact on Global Climate and 87Sr/86Sr Ratio of
               Seawater [#3600]
               This study emphasizes the major impact of the emplacement and weathering of Deccan Traps on geochemical
               cycles, in particular the carbon cycle. Futhermore, it allows us to suggest an origin for some anomalies around
               the K/T boundary.

           Savenko A. V.
               Regularities of Behavior of Strontium, Calcium, Fluoride, and Boron in River Mouths of Russia and Adjacent
               Countries [#3179]
               As a result of field observations done in 1993–2000 in mouth areas of 11 rivers in Russia and adjacent
               countries, quasiconservative behavior of calcium, strontium, fluoride, and boron has been proved.

           Kohler M. Meece D. E. Davis J. A.
              A Comparison of Methods for Estimating Sorbed Uranium (VI) in Contaminated Sediments [#3878]
              Four different extractions and isotopic exchange experiments were carried out on uranium-contaminated aquifer
              sediments to determine the quantity of sorbed uranium(VI). The results show good agreement between isotopic
              exchange and high pH carbonate extractions.

           Gislason S. R. Eiriksdottir E. S.
               Al Toxicity at High pH Caused by Diatoms? [#3464]
               Primary production of diatoms in Lake Ellidavatn, Iceland, caused pH and Al concentration to reach toxic
               levels. Basic water passing over fish gills becomes more acidic, possibly leading to precipitation of Al and
               respiratory problems.

           Tomascak P. B. Hemming N. G. Pedone V. A.
              Lithium, Boron, and Strontium Isotope Constraints on Solute Sources for the Great Salt Lake, Utah [#3758]
              Li and B isotopes may be highly fractionated in surficial processes, and thus may be useful as geochemical
              tools. As Sr isotopes in Great Salt Lake water are correlated to lake level, we compare Li and B data to
              interpreted Sr sources to the lake.

           Mora G. Jahren A. H.
              Changing Biohydrology Along a Precipitation Gradient: Insights from Stable Isotope Measurements [#3136]
              We report upon the effect of rainfall on fluxes of evaporation and transpiration in deciduous forests of southern
              United States as expressed through hydrogen and oxygen isotope-ratios in rainwater, soil water, groundwater,
              and water extracted from plant tissues.

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