C&N&DIA.N AOURNAL OF EXPLORAITION GEOPHYSICS
““L, 30. NO, 2 ,DECEMBER 19941, P, 103~114
PETROLEUM GEOLOGY OF NEPAL’
OR. FRIEDENREICH*, O.L. SLIN$, U.M.S. PRADHAN~ AND R.B. SHRESTHA~
The project was a team effort consisting of Alconsult
Magnetic. gravityandseisn1ic exIcnSi”e
surveys, geologicalfield professionals in the fields of geology, geophysics (seismic,
mapping programs. StrUCtUlal straiigraphic studies and
prtr”le”m grochrmicill in”esligati”nshaveher” carried““I in ,hr gravity), sedimentology, petrography and photogeology
Trrai plains andthe adjacent Siwalik Fold Belt of southern Nepal along with petroleum geochemists from the Geological
sincethe lxc 1970s. work. which hashem recentlyincorp Survey of Canada and geologists from the Petroleum
ratedinto a comprehensive evaluation. that
mrac,iYe petroleumpor,ihihties. Rockswith iignificam xn”rCe Exploration Promotion Project of Nepal. The work done by
potential havebeensamplcd from oumops.andlhcmal modelling the team consisted of: a) reviewing all petroleum-related
ruggcsts ill theprDspecli”r 01Ncpd ,hesc potentialS,~“ICC information on Nepal and environs: b) collecting and analyr-
rocksarein theoil andgasgmerationwindow.Effectiveresewoirr
Emcxpeccml beloud in IhCt,.owcr
to Siwalik.S”rkhCI Condrana
amI ing oil and gas seep samples; c) conducting field traverses
sandrtoncsand in the carhonatci of the I.akharpata~Vindhyan throughout southern Nepal to collect samples for geochemi-
G*O”p. cal and petrographic analyses; d) field mapping (structure) in
Enpl”rati”n “pp”nunities in the Trrai includeStl”Cl”lrSilSS”Ci~ selected critical areas; e) studying the sedimentology 01
atedwith blind thrusts.hascment~con,rollcd and bull ~b’uc-
drape potential reservoir rocks; and f) reviewing and interpreting
twes, stratigraphic pinch-outs and suhcrop trapr. Major folds and
thrusts theSiwalik FoldBelt arelikely to providestr~ctwaltraps.
in all the existing Nepal geophysical data.
Ddling dcplh* to ohjeclivcs arc hm 1500105000mctrc*in the
Teraiandfrom25011 4000rncmsin theSiwalik FoldBell.
fo 4.0 DATA BASE
The data base included all previous work in which the
PEPP/DMG was involved. This data included: a) more than
IO years of geological field mapping (Schroeder, 19X I ;
This paper is based on the recently completed Nepal Source Shrestha and Shrestha. 1983); b) a regional aeromagnetic
and Seal Study conducted by Alconsult International Ltd. survey (CCC. 1980); c) a photogeological study (Hunting
(AIL) and the Nepal Petroleum Exploration Promotion Project/ Geology and Geophysics Ltd., 1984); d) results of several
Department of Mines and Geology (PEPP/DMG) HMG of geochemical investigations (Kay&ha, 1989): e) information
Nepal (Slind, 1993). Geochemical sample collecting, labora- from the Shell Biratnagar I well; and f) basic field data and
tory analysis, interpretation and modelling was conducted by interpretations from four geophysical surveys: 1983. I984
the Geochemistry Section of the Institute of Sedimentary and World BankKGG 1250 km reflection seismic program
Petroleum Geology (ISPG) of the Geological Survey of (Harris, 19X4), 1987.1988 PClAClAirborne 1651 km retlec-
Canada. The study operated under the overall direction of tion seismic and gravity program (Friedenreich and Slind.
Petro-Canada International Management Services (PCTMS) for 1989), 1988-1989 Shell Nepal 1940 km (615 km used in this
the Canadian International Development Agency. interpretation) reflection seismic program, 194 l-1993 French
Government/CGG 422 km retlection seismic program.
2.0 OtSJECTtVE STUDY
5.0 GEoCnAPHICAL/GEoLoCICAI. SETTING
The main objective of the study was to better understand
the petroleum geology of Nepal and to define its oil and gas The Kingdom of Nepal, an independent country lying
potential by combining existing data with new information between India to the south and China to the north (Figure I),
acquired during the course of the study. is 800 km long from east to west and ranges in width from
‘Presented at the CSEGKSPG Joint Convention, Calgary. Alhem, May I I. 1994. Manuscript received hy the Editor October 17. 1W4; wised manuscripr received
January 23, 19%
2AI~~n~~It lntrmationai Ltd.. 450.5X1 6th Avenue SW.. Calgary. Alhem T2P US2
?HMG Nepal Petroleum Exploration Promorion Project. Dcpartmcnt of Mines and Geology. Kathmandu. Nrpai
Thanks are given fo Psrro-Canada lnterna&mal Management Services. prqject managers for Canadian International Developmcnl Agmcy. and IO Lhc Pclmlcum
Exploration Promotion Project ofthe Departmcm of Mines and Geology of His Majesty’s G,ovcmmen~ d Nepal Curlhcir a~sisuncc in prcpring rhis paper.
ClECi 103 DccvlllbcrIV94
O.R. FKIEDENREICH. 0.L SLLND, U.M.S. PRADHAN and R.B. SHRESTHA
130 to 230 km. The country is naturally separated into four Group) thrust to the south (Parkash et al., 1980; Herail et al.,
major geographical/geological zones that parallel its long 1986). Gravity measurements and detailed field mapping indi-
dimension (Frank and Fuchs, 1970; Mitchell, 1979; StRcklin, cate that the cores of at least some of these structures contain
1980; Windley, 1983). Each zone has its own characteristic pre-Siwalik rocks that are considered to be hydrocarbon explo-
stratigraphy and structure and these zones are, from south to ration objectives (Friedenreich and Slind, 1989; Ebner, 1989).
north, described below (Figures 2.3). The Siwalik Fold Belt and the Terai are a pat of the fore-
land of the Himalayas (Parkash et al., 1980). They have
5.1 Terai some similarities with the foothills and western plains of
The Terai is the Nepal portion of the Indo-Gangetic Plain Alberta and British Columbia and are the main areas of
that extends from the Indian Shield in the south to the petroleum interest in Nepal.
Siwalik Fold Belt to the north. The Plain is a few hundred
metres above sea level and is underlain by a thick, relatively 5.3 Lesser Himal
flat-lying sequence of Mid to Late Tertiary molasse (Siwalik The Lesser Himal is a wide, stratigraphically and strut-
Group) which unconformably overlies subbasins of early turally complex zone that lies immediately north of the
Tertiary to Proterozoic sediments (Surkhet, Gondwana and Siwalik Fold Belt and is separated from it by the south-verging
Vindhyan Groups) and igneous and metamorphic rocks of main boundaty fault (MBT). The majority of the Lesser Himal
the Indian Shield (Agrawal, 1977; Acharyya and Ray, 1982; is composed of thrust sheets and nappes of metasediments and
Raivemun et al., 1983). The only deep well in Nepal (Shell igneous rock of the Midland Super Group. The Group is of
Nepal B.V. Biratnagar 1, TD 3530 m in 1989) was drilled in little hydrocarbon exploration interest, although the oil and gas
the far eastern part of the Terai. seeps of the Dailekh area occur within the Midland Group
(CPIT, !973). These seeps are interpreted to have been gener-
5.2 Siwalik Fold Belt ated in sediments below the nappes (Figure 2).
The Siwalik Fold Belt is from 5 to 45 km wide and rises
abruptly from the Terai along the main frontal thrust (MFT). It 5.4 Higher Himal
consists of a series of ridges and valleys composed of thick The Higher Himal, which contains the spectacular peaks
beds of folded and fault-repeated Tertiary molasse (Siwalik of the Great Himalayan Range, Everest, Annapuma, etc., is
80” 82” 84” 86”
S-N: Approx. Location of Schematic
Cross-Section Fig. 2
0 : Biralnagar - 1 Well
82’ 84” 86’ 88”
I I I I
Fig. 1. Geological map of Nepal.
CIEC 104 December IV94
PETROLEUM CEOLOCY “t- PvEPAL
thrust southward over the Lesser Himal by the main central not adequately dated, but is intcrprcted to be older than
thrust (MCT; Figures I, 2). The zone is composed of a basal Carboniferous and to range well into the Precambrian (Frank
slab of metamorphic Proterozoic rocks overlain by a con- and Fuchs, 1970; StGcklin, 1980).
formable sequence of Cambrian to Eocene Tethyan sedi- Duilekh Group ~ The Dailekh Group, the lower part of
ments (Bordet et al., 1981). Gas seeps occur in the upper the Midland Super Group, is made up of phyllites, garnetifer-
Tethyan of northern central Nepal near the village of ous schists, feldspathic greywacke, volcanics and stroma-
Muktinath (Figures 1.2). tolitic dolomites (Figures 2, 7). These rocks have been raised
to the low green schist facies in the centre of the Midlands
6.0 STRATICRAPHY and the metamorphic grade increases in successive thrust
sheets to the north (Mitchell, 1979; Bordet et al., 1981). The
The following discussion concentrates only on those rock
rocks of the Dailekh Group are not considered to bc cxplo-
units that have a direct bearing on hydrocarbon exploration
Vindhyun Super Group ~ Vindhyan sediments, equiva- Lakharpata Group ~ The Lakharpata Group occupies the
lent to those of the great Vindhyan Basin of Northern India, upper part of the Midland Super Group and, although not
are interpreted to extend beneath the Ta% and Siwalik Fold firmly dated, is interpreted to be of Late Precambrian to Late
Belt. The Vindhyan is reponed to have a maximum thickness Paleozoic ages (Stiicklin, 1980: Shrestha and Shrestha,
of 5250 m (Agrawal, 1977; Srivastava et al., 1983) although 1983). It is unconformably overlain by frequently organic
at least 12 000 m of pre-Tertiary seismic reflections have dark shales and sandstones of the Gondwana and Surkhet
been observed under the Terai. The Vindhyen, which is con- Groups. This Group and its Vindhyan equivalent are an
sidered to be a major hydrocarbon exploration objective, important exploration objective.
consists of an unmetamorphosed sequence of stromatolitic The Group contains the following formations and mem-
limestone, shale and sandstone. Although dating is difficult, bers:
the Vindhyan is considered to be equivalent to at least a part Sangram Fm: Greenish grey to black splintery shale, con-
of the Lakharpata Group of the Lesser Himal. taining zones of relatively rich organic intervals (up to 9%
Midland Super Group - The Midland Super Group, TOC); some shales being burned for fuel; major potential
which encompasses most of the rocks of the Lesser Himal, is source rock:
m ALLtJWUM SURKHET GP GRANITE
m SIWALIK FM LAKHARPATA GP OPHlOLlTE
m GONDWANA GP m b;$@&,C ROCKS m VOLCANICS
“INDHYAN GP TETHYAN SEDIMENTS SEEPS
BASEMENT HIGH GRADE
MFT MAN FRONTAL THRUST THRUST
MET MAN BOUNDARY THRUST MCT MAIN CENTRAL MMT MA!NMANTLETHRUST
Fig. 2. Schematic cross-section through central Nepal
CIEG 105 Drcrmbr ,994
MAtNT;;;;y LESSER HIMAL
SIWALIK FOLD BELT
PLIOCENE ;$$gi.z; I LOWER
UPPER v SURKHET MIOCENE
CRETACEOUS -GONDWANA TaOUP’
“INDHYAN - SOURCE ROCb
Fig. 3. Stratigraphic zonations of central-southern Nepal.
Ramkot Fm. Pink to grey sandstone and purple to grey fauna. The formation has a few intervals that contain up to
shale 850 m thick; 10% TOC and is considered an important potential source
Gawar Fm. Limestone and dolomite with abundant stro- rock. The Taltung Formation disconformably overlies this
matolites and algal mats and becomes more shaly and sandy Sinse and is comprised of conglomerate sandstone shale.
upwards; reaches a maximum thickness of 1700 m and is Gondwana sediments are considered an exploration objec-
considered an exploration objective; tive in Nepal. They probably occur in small pockets beneath
Khara Fm. Dark grey, microcrystalline limestone and the base Siwaliks (Figures 8, 9) in the eastern Nepal Terai,
shale; possibly in the Gandak depression in the Birganj and
Katwa Fm. Dark grey to black shales with minor stroma- Lumbini areas and could be caught up in smaller thrust slabs
tolitic dolomite; a potential source rock; beneath the Siwalik Fold Belt and main boundary thrusts.
Am Fm. Dense dolomite with lesser amounts of sandstone Good reservoir rocks were not seen in outcrop hut several
and shale; restricted to south-central part of Nepal; a poten- organically rich intervals have been mapped. The lower coal-
tial subcrop reservoir. hearing Gondwana could be both a source and reservoir for
Gondwana Group (Late Carboniferous to Early gas and the marine Upper Gondwana may be a potential oil
Cretaceous) ~ The Gondwana is a group of rocks occurring source rock.
in basins on the lndian Craton (unconformably below the Surkhet Group (Late Cretaceous to Early Miocene) - The
base of the Siwalik Group of the Terai) and in the southern Surkhet Group occurs in the southern, central and western part
thrust sheets of the Lesser Himal. The thickness of the Group of the Lesser Himal where it unconformably overlies
in eastern and central Nepal, which is quite variable, is Lakharpata or Gondwana rocks. The Group attains a maximum
approximately 1000 m in the ridges immediately above the thickness of 1200 m and is separated into the Melpani, Swat
MBT in central Nepal and is interpreted from seismic analy- and Suntar Formations (Sakai, 1983). The Group is correlated
sis to be at least that thick in the basins of the Terai (Bashyal, with the oil and gas producing formations of the Assam and
1980; Sakai, 1985; Datta et al., 1983). The Group is sepa- Potwar basins (Rangarao, 1983) and with the “Unnamed
rated into two formations. The Sisne Formation uncon- Formation” of Northern India (Schroeder, 1981) sediments.
formably overlies the L&harp& Group and is composed of The Swat Formation is composed mainly of shale that
diamictite and shale and contains late Paleozoic marine contains intervals with greater than 2% TOC and some of the
CEG 106 DIsElnkr lYY4
Mrlpani organic shnlcs have 20%, TOC. In the Danp Valley, southern Nepal. Seismic control in eastern Nepal is quits
the porosity of a distinct Melpani sandslonc is filled with dense (appnximatcly 2 km x 4 km). This xca is character-
solid hydrocarbon Wind, IYY~J. ired by many bassment~contn,llcd structures offsettin@ srdi-
Siwdik GIW[I (Late Miocene to Pliocene) ~ The Siwalik ment-filled suhbasins and erabcns beneath the Siwalik
Group is a thick section of fresh-water molasse. sxposcd in a molasse. The grid (IO km x IS km) of rcconnaissancc s&s-
ssties of fault slices that make up the Siwalik Fold Belt and lit
mic lines covering the halance of the Terai has identified
beneath the alluvial deposits of the Tcrai (Delcaillau, 19x6).
se~cral gculogical settines which hnvc the potential for
The Group is up to 4500 m thick and is scpxated into three f&
hydnxarhon pnxpccts. Thcsc include structured traps rclatcd
mntions: Lower Siwalik (LS), Middle Siwalik (MS1 and MS2)
and Upper Siwalik (US). The lower part of the Group i\ con- to normal faulting involving prc-Siwalik formations and
posed of fine-grained sandstones containing shale intcl-vals (IS thrusting involving the Siwaliks (Fi@w 4): subcrop traps
and MS I ) and becomes cot~rsfr @nrd upwards (MS2 and involving pre-Siwalik sequcnccs (Figure 51: and structural
US). Petroleum ohjcctives are expected to he restricted Iu the trap\ associated with blind ti~lds in front of the Siwalik Fold
lower part of the Group where thcrc is an effective combination Belt (Figures 6. 7). The location\ of seismic lines show11 in
of potential sandstone rcscr~oirs and shale se&s. Fipures 4. 5 and 6 are shown on Figure 8.
The hasc Siwdik seismic marker (Figures 4, 5, 6) is an
7.0 GEoPHYStCs important reflection in the Tel-ai region. It rcprcsents an
Geophysical exploration methods, rcflcction seismic. oncunlbunity that separates the Siwaliks (mid-Miwxnc and
jiravitv and magnctics, combined with surface mapping and younger) fri~nt older strata (L~wel- Miucenc to Precambrian).
hasin analysis. have cstahlished the subsurlhcc fmmewo~-k uf Figum 8 and Y reprcxnt structural maps of this marker in
Fig. 4. Migrated Line 59 in eastern Terai. showing two stages of thrusting (see Figure 8 for location)
(‘1i, i 107 ,kr,l,,rr, ,,,I,
“,R. FRIEDBNREICH. 0.L SI.,ND. I,.M.S. PKADHAN and R.B. SHKCSTHA
TERAI SIWALIK FOLD BELT ” LESSER HIMAL
SCALE: H = V
Fig. 7. Structure cross-section along tine 31.
the eastern and western Terai, respectively. The unconfor- seeps is interpreted to c”me from a conventional s”urce rock
mity lies between 3500 and 4600 m below the Terai plain beneath the nappes and rocks with source potential have been
which is approximately 100 m above sea level (al.). There is sampled from the Lakhqaw, Gondwana and Surkhrt Groups.
no dominant east-west gradient to the base Siwalik marker; Thermal modelling suggests that potential source rocks in the
however, the dipping of the marker toward the Siwalik Fold prospective part of Nepal are in the marginally mature-f”l--oil
Belt is very apparent. t” late-in-the-gas generation window.
Nine seismic and gravity traverses cross the Siwalik Fold
Belt and identify major folds and thrust faults that may con- 9.0 R~sliwom
tain substantial thicknesses of potentially prospective pre-
Siwalik rocks. Line 89 (Figures 9, IO) cr”sses a large Siwalik Studies of outcrop samples and analysts of Shell
fold and demonstrates good reflections on the flanks of the Biratnagar I indicate that effective reservoirs and seals are
structure but there is no coherent date in the core. Gravity likely to be found in the Lower Siwalik, Surkhet and
measurements along this line show a substantial 25 mgal Gondwana sandstones and shales. Outcrop studies have not
anomaly above regional f”r the traverse. Model studies show identified large areas of carbonate reservoir development in
(using densities derived by methods described by Gardner et the Lakharpata/Vindhyan Group, although it is expected that
al., 1974) that the anomaly is caused by highier) density rocks the unconformity at the base of the Siwalik molarsc will pro-
being involved in the core of the structure. These model den- vide a large number of attractive carbonate as well as cl&c
sities are comparable with those of the prospective pre- exploration objectives.
Siwalik (Lakharpata) dolomite (Figures I I, 12).
From the above, it is apparent that the gravity method may 10.0 DRILIJNG
be very beneficial and cost-effective in c”ncert with seismic
Nepal is virtually unexplored. The country’s only well was
surveys in delineating hydrocarbon prospects in the southern
drilled on a seismically defined, basement-controlled
put of Nepal.
anomaly in the far eastern part of the country near
Biratnagar. The well was abandoned at 3530 m after pene-
trating 3143 m of typical Siwalik molnsse and 387 m of
A considerable amount of geochemical work has now been arkose and shale that was interpreted to be of Eocene or
completed on rocks from Nepal. The oil from the Dailekh younger age. No hydrocarbons were reawered, although
C)H(; 110 ,w*
PCTROLF,UM clxxocY or NEPA,
SWAM FOLD ii 28N
m SiWALlK MOLASSE
Con,o”is in m bsi
0 50 km
Line 59: See Figure 4
Line 52: See Figure 5
Line 31: See Figures 6 & 7
83E 84E 85E 86E 87E
Fig. 8. Eastern Terai. structure map 01 Base Siwalik unconformity and location of Lines 31, 52 and 59,
small amounts of background (mud) gas were encountered in Compagnir GenCriilr de Geophysiqur (CCC). 19x0, Fin>,, report airborne
rnagnetomcter survey Nepal: Unpubl. Rep. for the Nepal Dept. of Miner
the lower part of the Middle Siwalik.
and Geulogy. 91p.
“nlld, N.R.. Milru, ND. and “undyopndhyay. 19x3. KeCem trends in the
11.0 OPPOHTUNITIW study 01 Gondwaoa hasins of Peninrula and extra-Peninsuliir IwJia:
Femlrum Ahi2 Journal,
Exploration opportunities in the Terai consist of structures Uelcaillau, B.. 14Rh. Dynanlique et e”“l”ti”n morph”.structurale d” piemont
associutcd with blind thrusts, bascmcnt-controlled structures, frwml de I‘Himalaya: ies Siwaliks du Ncpvl oriental: R&w dc Ciulugiu
stratigraphic pinch-outs and subcrop traps. Major folds and Dynamiquc a de GCographic Phyriquc. Paris. 27. Fast. 5, 3 19~337.
thrusts in the Siwalik Fold Belt are likely to provide strut- Ehner. E.J.. IVXO, Grwity survey. acquisition, pmcc*sing and intrrprclalion
mport. Terai and Siwalik Fold Hclt, Kingdom of Nepal: ELS Consulting.
turally controlled traps containing Lakharpata to Siwalik Oct. ,9x’).
reservoirs. Drilling depths to objectives are from 3500 to Frank. W. and Fuchs. G.R.. 1970. Geological investigations in West Nepai
5000 mctrcs in the Tcrai and from 2500 to 4000 metres in and their signilicancr Cur Ihr geology oi Ihr Himdayas: Geolugische
I<snd\cha” 5”. 552.580.
the Siwelik Fold Belt.
Friedenreich. O.R. ilnd Slind. O.L.. 1989. Ncpdl gcologicai and geophysiL
cal report of the 1987-19X0 Joint DMWPUAC seismic and gravity pm-
REFEREUCES gram: Alconsok Intrma~iond Ltd.. Oct. 1989.
Gardner, G.H.F.. Gardner L.W. and Gregory AR., 1974. Foitnafion velocity
and density the diagnostic hnsici. for stmigr;q+ic traps: Geophysics 39.
Hwris. I.R., li)W. An imrgmrd grolu~ic;ll~erophysicai inlerprr~aiion ni Ihc
1982~84 ~eirmk reflection survey dilra, phaw II of the pctmlcum cxplo~
ration ilnd p~~omnlion projccl Ibr OK Depilrlmenl d Minus and Gunlogy of
His Majesty’s Giwsrnn~eat of Ncpul. 9 i 11.
Sashyiil, R.P.. I WI. Gmhen;i type 01 hrmi~lion with phosphatic rocks in
S.E. Nspai: J. Grol. sot. liidiii. “ct. 1%m 484~14~1. Hcmil, G. Mode. G an* IMCililhU, H., IWh, LCS Siwalik de i‘Himaiaya
Bordst. P.. Colchsn, M.. Ls Fwi. F. and Pcchrr. A., ,981. The grodynmic du Nepal: un cnaniplc d~ebduiion gmdynnmiqoc: d’sn prcsure d.accrs-
wd~ti~n of the Himalaya teclycm of reie;irch in central Nepal and some lion inlrd conlincnlid Sciencch dc 18Tcm, Mcnl. 437. 155~182.
odxr regiunr: kc. Ciilhoi.. Paris. hncc: Univ. Poiiicrs. Lab, PcWui.. Hunting Geoiogy md Geophysics, Ltd.. 19X4. A photi~geok@zal study u(
Surf. Frmce. suulhern Uep;il: Unpuhl. Rep. lor he Nrpitl Dcpartmen~ of Mints and
Chinesektcde~in Investigation Team ~CI’IT~. 197.3. Report on the iwciti- Gcol<,gy. zap.
gadan of pciroicum pcology in rhc Kingdom of Nepal: ChinesePctrolem Kayasrha. N.L.. 1989).Kepon on gcochcmical sludics of field samples from
Corporation.Peking. CHN. 75 6uhfile B. 7bO582.75~203541. Nqal: PE.PP,“Mc; ivcpui. May IW9.
(IK 111 I>rwlilhrr i’l’,.l
81E 82E 83E 84E
m LESSER HIMAL SEQUENCES 29N.
2222x,, m SiWALlK FOLO BELT
j: SWAM MCILASSE
Contours I” mlt’s,
Lx 896s Figures 10, 11 & 12
8iE 82E 83E 84E
Fig. 9. Western Terai, structure map of Base Siwalik unconformity and location of Line 89 (Siwalik Fold Belt traverse)
Mitchell. A.H.C.. 197’).G”idCS10nmai pro,,inces in the Central Himalaya Sltkklin. 1.. 1980.Geology of Nrpal and ttr rcgmn:~lIriimr: J. Geol. Sot.
Coili5ion Reli: ,hc Ya,“r “i rrgionai stratigiaphic C”rrelati”ni and ,cc,ollic Lmdon 137. 1-34.
anidogics:Gcdogiual Society of China. Mcm. 3. 167~ (94. of
Windlcy. R.F.. 19x3. hlem,>qJhism nnd teCtOlliC1 ttlc Himalaya: J. Cd
Parka\h. 8.. Shama R.P. and Roy. A.K., IW,, The Siwalik GW”,, sot. hndon 140,84%X05.
~rdaire, iediments shed hy colli\ion ur conlincnlal plate*: Sedillient.
Gml. 25, 127-15’).
Raivrrman. V,. Kuntr, S.V. and Mukhcrjca, A.. 1’183.Basin geometry. FOK
REFEKENCES GENERAL READWC
Ccnwoic redi,,,snrutio,~ anil hydrucarhon pmspccts ill Nor,h wes,er,, Dspnrtment of Mines and Nepill
~;cology CDMGh Nepal:IWi, exploration
Himlayu and lndo-Cia”gcric Rein,: Pclrolcum Asia humal 6. no. 4. h,- oppurtuniries:Bmchurc.
Riing*rm. A.. 14x3. Geology an* hydrucarh”” pdcnlial Of>/pan of Assam-
~, 1990. Bmchure.
Exploration opportunih in Nepal:
Ankan Basin and its adjwcm rcgim. in Pelloliirruui basins of India: ~( The
19w. King&,“7 Nepal.<>l expl”rati”” Brochure.
Prtroleum Ah Juumal 6. 127-158. .!..
Ganrser. 1%9. o/the Wiley
Geology Himulayas: Inlcrscicncc. Lundon.
S&i. H.. IUS5 Gedogy of the Kali Gandaki Sup Group: Mm kc. Sci.. New Ywk.
Kyushu Clniv.,Ser. 13.C;col..WI. XXV. nu. 3.137-397. C.;and IWh. UI
Karunilkaran. Rm A.R.. Slatu, cxpluraiion hi hydmcarbon
Schrocdcr.J.W., 1’181, rrpun 0” petrolmm cxploralion “1 Nepal: Unpubl. in lhc Himalayx imd
region contributions lo rlratigraphy slru~tw~:
Rep. Ibr ,hc Nepd Dspartmentnf Miner and Gculugy. 74p. Himalayan Gculugy Sec. New
Seminar. 111, Delhi. Mis Puhl. Sure.Gcol.
S,,rcs,,,;,. S.8. and Shrerthn. J.K. 1’)83. The gr”lugical cnap of westem 41
Crnlral Nepal: His Majesty.\ Guvclnmral. Ministry of Industry. P. ‘The
Moinar. ilndTupponnier. I’,. 1477. collthion hcluccnIndiiiand
Depsrlmcnld Mines and Geology. Lnmcbour, Kathmundu. 236.
Curasi;i:Scientific American no 4.2W I
Shd. O.L.. 1w3, Nqxll. sourceand Xii\ Wd\. hydri,carh<ma~sessnx”l or Ir5.P. .llKl
Sc;,rle. ei a,..,987.Thething of .Trthy* tllc WClO”iU\Ihe 01
southernNepal: Alci,il\ult Intermli”n31 L.fd..July ,993. Bull. sot.
Hirn;d;,y,: mm,. Am98.hSX~,ill.
Sri”ao2dra.R.N., Rana. M.S. alid “ermn. N.K.. 1983,Cc”l”fy and hydlov KC..
Shxma. 1990. Ccohfyof Ncpnl and
Hmolsya adjaccni cuwmics:
carbo prnrpccri OilhC “indhyen Bssin: I’etmleiim Asia Journal6. Shwm;,. Nqa’.
Sangeel;, Hishnl Ka,h,llan<i”. Jan. Nepal. ,690.
c,,:ci 112 Wil
O.K. FKIEIxaKEICII. O,L, SLlNLl LI.M.S.WADHAN :ind K.B. SHKESTHA
LVMBlNl PLAiN SOMESHWAR RAPTI “ALLEY MAHABHARAT
RANGE (ES,) LEKH
PLEiSTOCENERECENT ChRBONlFEROUS TO
MIOCENE PLIOCENE SCALE: H =”
GD GONDWANA GP
su “PER SIWN.lK 0 5 k”,
A THRUSTFAULTS SM MlDDLESIWRUK PRECAMBRIAN 70
G G SEISMICMARKERS PAEOLOIC
X CRETACtOUS MlOCENE “IN “INOHYAN GP
x SEiSMlCREFLECT LK LAKHARPATA GP
SN SUNTAR MB1 MAIN BOUNDARY THRUST
SW SWAT MFT, MAIN FHON~reL lHHUST
Fig. 11. Structure cross-section along Line 89.
c 720 CALCULATEDGRAVITY
0 5 10 15 20 25
0 5 10 15 20 25 30 SCALE
Fig. 12. Model study for Line 89 (Siwalik Fold Belt traverse).
(lMi 114 ,‘,‘W