STRUCTURAL INHERITANCE IN THESOUTHERN KIRTHAR FOLD BELT

ABSTRACT

Field data, seismic evidence and the results of recentdrilling in the southern Kirthar Fold Belt (KFB) haverevealed that the location and magnitude of many ofthe large fold structures can be attributed to inversionof an earlier set of normal faults. Our current analysissuggests that Jurassic rifting produced a rift zone in thewest flanking a stable platform with only minor faultingto the east. This structural template had a profoundeffect upon the sedimentation patterns and structuralgrowth of the younger cover sediments.

Evidence for Jurassic normal faults is seen in the JurassicShirinab Formation of the Mor and Kulri Ranges in thewestern part of the fold belt where carbonate debrisflows and massive slump blocks record syn-depositional,fault-related fragmentation of the margin of the carbonateplatform to the east. Examples of these faults showevidence of inversion with contractional structures inboth footwall and hangingwall yet with overall netextension.

East of the Mor Range, Jurassic outcrop is absent.Seismic data indicates that the Jurassic platform is notaffected by major faults. Yet facies trends in the Tertiarycover sediments and the location of Tertiarycompressional structures appear to be influenced bythe location of earlier extensional faults. The Chapar-Andhar High is flanked by an orthogonal system offaults which has controlled the dimensions of the Eocenecarbonate platform that underlies the structure. Thetrend of these faults is parallel and perpendicular to theJurassic faults recorded in the western KFB (NNW-SSE and ENE-WSW). The main Eocene platformmargin on the Gorag Ridge to the east is very abruptand consistent in strike suggesting fault control. Theseobservations are consistent with sub-seismic scale

Jurassic faults being present on the platform.

The main inversion event took place during Plio-Pleistocene collision. However an important phase ofearlier inversion occurred in the Late Palaeocene relatedto the emplacement of the Bela Ophiolite onto themargin of the Indo-Pakistan Plate in the Kirthar area.Seismic evidence demonstrates that substantialaccommodation space was generated during loading ofthe passive margin by ophiolite emplacement.Subsequent infill of this marine ‘foreland basin’ isreflected in the rapid westward thickening of SequenceT20 within the foldbelt. Subsequent pre-collisionalinversion events have been recorded in the EarlyOligocene and Early Miocene and are attributed totransfer of stress through the plate from the Himalayancollision zone, dating from the Early Eocene.

Despite the evidence for repeated Tertiary inversion ofearlier normal faults, this is not thought to be the maincause of structural elevation of the mountain belt.Instead this is attributed to thick skinned buckle foldingat a crustal scale.

INTRODUCTION

Between 1994 and 1997 Eni-LASMO Pakistan andpartners acquired exploration licences covering an areaof almost 13,000 square kilometres in the southernKirthar Fold Belt (KFB) of southern Pakistan (Fig. 1).This acreage covers Recognition of these earlyextensional structures and the timings of subsequentinversion plays a major role in the exploration forhydrocarbons in the southern KFB. It is crucial thatthe geometry and timing of early structural growth bedetermined in order to constrain the results of basinmodelling, source rock maturation and hydrocarbonmigration studies.

1Earth Resources Limited, Innovation Centre, Singleton Park,Swansea, SA2 8PP, UK2Eni-LASMO Pakistan, 5th Floor, The Forum, G-20, Block 9,Khayaban-i-Jami, Clifton, 75600 Karachi, Pakistan* Present address ROC Oil Company Limited, 100 WilliamStreet, Sydney, NSW 2011, Australia

John D. Smewing1, John Warburton2*,Antonio Cernuschi 2 and Nazir-Ul-Haq2

Fig. 1 - Location map. Eni-LASMO foldbelt acreagein green.

Recent analysis of depositional sequences in the southernKFB [1, 2] has resulted in accurate dating ofdeformational events on the passive margin. We expectthe next breakthrough in our understanding of the KFBto be a better knowledge of the relationship between

early extensional faults, their impact on depositionalsetting of reservoir, source and seal facies and theirsubsequent behaviour during Tertiary compressionaltectonics. To this end, surface and subsurface data arecurrently being integrated to produce a coherentstructural model. This paper highlights several keyobservations made to date.

TECTONIC SETTING

The KFB forms the southern part of the Western FoldBelt of Pakistan [3] located adjacent to the present daystrike-slip western margin of the Indo-Pakistan Platerepresented by the Ornach-Nal Fault System and theChaman Fault (Fig. 1). The southern KFB consists ofJurassic to Miocene sediments exposed in a series ofdoubly plunging N-S to NNW-SSE anticlines andelongate anticlinal ridges, separated by broad synclines. The folds die out eastwards beneath the KirtharForedeep, a deep trough infilled with up to 5km of Plio-Pleistocene molasse.

The southern KFB is bound to the west bythe Bela Ophiolite (Figs. 1 & 2). This ophiolite wasformed in the Maastrichtian around 70Ma and obductedonto the continental margin shortly thereafter with finalemplacement taking place in the Late Palaeocene toEarly Eocene (~50Ma) [4].

MAKRANFOREARC

BASIN

CH

AM

AN

FA

UL

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ENGLARGEDIN FIGURE-2

Porali Trough

Makran SubductionZone

INDIA

KARACHI

MURRAY

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66 E 68 E 70 E

0 100 km

24 N

26 N

28 N

30 N

SULAIMANFOLD BELT

BELAOPHIOLITE

Recent & sub Recent alluvium

KIRTHAR PROVINCE

Gaj, Manchar & Dada Fms-Neogene

Nari Fm - Oligocene

Kirthar, Ghazij & Laki Fms - Eocene

Ranikot Fm - Palaeocene

Pab Fm - Maastrichtian

PAB PROVINCE

Kohan Jhal Fm - Late Eocene - Oligocene

Khude Fm - Late Palaeocene - Middle Eocene

Rattaro Fm - Palaeocne

Pab & Mughal Kot Fms - Late Camp - Maastr

Cretaceous

Jurassic

Bela Ophiolite

0 15Km

26o 45'

26o 30'

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Within the KFB itself, the western margin of the KirtharRange (Fig. 2) marks the line of the shelf-slope breakfrom the Maastrichtian until emergence of the mountainrange in the Neogene. Abrupt changes in lithofaciestake place across this line. The area to the west of theline is referred to as the Pab Province and that to theeast as the Kirthar Province, each with its ownlithostratigraphic nomenclature (key to Fig. 2).

RIFT-DRIFT-COLLISION HISTORY

The KFB is located on the NW margin of the Indo-Pakistan Plate. The rift-drift-collision history of thisplate is well documented [5, 6, 7]. The oldest sedimentsexposed in the southern KFB are limestones with minorclastics of Early to Middle Jurassic age. These weredeposited during a lengthy period of passive subsidenceprior to separation of the Indo-Pakistan Plate from theAfro-Arabian margin in the Oxfordian. During the pre-rift, rift and drift phases of this margin up to 9km ofsediments were deposited over the site of the KFB.

The drift phase was terminated by initial collision ofthe northern margin of the plate with Eurasia at 55Ma[7], around the Palaeocene/Eocene boundary. The BelaOphiolite was emplaced at this stage. The first northerlyderived Himalayan-sourced clastics were deposited inthe late Middle Eocene (40Ma) and up to 2.5 km oflate Palaeogene flysch (Kohan Jhal Formation) werethen deposited in a narrowing seaway between the Indo-Pakistan Plate and the Afghan Plate [8, 9]. Initial upliftof the mountain belt dates from the Miocene when thedepocentre of the Himalayan-sourced clastics switchedfrom a position west of the fold belt to the developingKirthar Foredeep to the east. The main phase ofdeformation and uplift however is of Plio-Pleistoceneage and is related to the final collision of the Kirtharmargin with the Afghan Plate along the proto-Chamanfault [8]. This event marks the first appearance ofsignificant westerly-derived clastics in the foredeep,replacing the hitherto northerly-sourced clastics.

Palaeomagnetic data for igneous units in the westernparts of the southern KFB (Bela Ophiolite, Cretaceoussills) indicate that they have been rotated anticlockwiseby up to 70 since emplacement/intrusion [10]. A similaramount of clockwise rotation has been found in thewestern Sulaiman Fold Belt [11]. The significance ofthis observation for the KFB is that the present NNW-SSE strike restores to a NE-SW orientation which isthe depositional strike of the pre-collisional margin.

The age of rotation in the KFB is not constrained bythe palaeomagnetic data. However the magnitude and

regional extent would indicate that the most likelytiming/mechanism is the Plio-Pleistocene collision ofthe NW margin of the Indo-Pakistan Plate with theAfghan Plate, and specifically the sinistral movement onthe Chaman and Ornach-Nal Fault Systems. The mappattern of the Makran folds to the west of these faultsystems reveals a similar anticlockwise rotation (Fig. 1).

STRATIGRAPHY

Stratigraphic nomenclature in this paper is based onrecent work [2] in which the lithostratigraphy of thesouthern KFB has been rationalised into a sequencestratigraphic scheme comprising 23 depositionalsequences (Fig. 3).

Fig. 3 - Stratigraphy of Southern Kirthar Fold Belt.

Each depositional sequence has been identified with akey letter (J for Jurassic, K for Cretaceous, T for Tertiary)and labelled in decimal units in ascending stratigraphicsuccession (J10, J20, J30 etc).

Analysis of these depositional systems has shown thatmany have resulted from tectonic events affecting theNW margin of the Indo-Pakistan Plate during its rift-drift-collision history. Identification of these tectonicsignatures has been instrumental in timing the inversionevents described in this paper.

JURASSIC-AGED FAULTS

In the western KFB three major high angle reversefaults have been identified in outcrop, boundingrespectively the Kulri, Mor and Pab Ranges. Fromwest to east these are the Wayaro, Jezar and Mor FaultsFigure-2. A variety of structural and stratigraphicobservations indicate that these faults were active duringJurassic rifting.

The evidence for this is best preserved in the Kulri andMor Ranges in the hanging walls of the Wayaro andMor Faults. In the Kulri Range, debris flows occurwithin a 15 metre thick shaly section within the pelagiclimestones of the Anjira Member and compriseindividual flow units 1-3 metres thick carrying darkgrey shelly limestone blocks of platformal character upto 1 metre across in a yellow calcareous mudstonematrix. Huge tabular slide blocks of interbeddedlimestone and shale, up to 2km across also occur nearthe top of the Anjira Member, lying concordant withthe surrounding bedding.

Although the constituents of the debris flows and slideblocks show a superficial resemblance to the SpingwarLimestone Member below the Anjira, the presence ofshells floating in the matrix of the debris flows identicalto those within the blocks themselves indicate that theywere sourced from semi-lithified shelf carbonates ratherthan older, deeper and presumably lithified SpingwarLimestone of pre-Toarcian age. This suggests theywere sourced from a penecontemporaneous carbonateplatform up dip to the SE.

This carbonate platform would have been the Bajocian-Bathonian Chiltan Formation Figure- 4 which occursin the subsurface in the Middle Indus Basin to the eastand outcrops in the northern KFB. It does not outcropin the southern KFB and no wells have been drilled tothis depth. Its former presence in the Gaj River howevercannot be ruled out as here all post-Toarcian sedimentshave been removed at the unconformity (SBJ50) below

Neocomian Sembar.

The Mor Fault may have marked the basinward limitof Chiltan progradation. The break up of the platformat the Mor Fault seems the most likely source of thedebris flows and slide blocks in the Kulri and Mor Ranges.

Fig. 4 - Palaeogeographic map for southern Pakistanin the Middle Jurassic showing proposed westernlimit of Chiltan carbonate platform defined byMor Fault.

Following maximum Chiltan progradation the platformwas exposed at SBJ50 in the Late Jurassic. The presenceof karstified platform limestones in basinally redepositedpalaeosols immediately down dip from the Mor Faultprovides further evidence that it was a major basin-bounding fault in the Middle to Late Jurassic.

Despite the presence of contractional structures in bothits hangingwall and footwall, the Jezar Fault is still inoverall extension (Fig. 5). Although the age of extensioncannot be dated, the structural geometry is consistentwith the evidence from the Wayaro and Mor Faults ofMiddle to Late Jurassic extension followed by Plio-Pleistocene contraction (inversion).

In the case of the Mor Fault, extension appears to havecontinued into the Early Cretaceous; the SembarFormation thickens eastwards towards the fault from300m to more than 2000m over a horizontal distanceof 10-12km. The possibility that some of this thickeningis due to structural imbrication cannot be excluded butit is nevertheless likely that original stratigraphicthickening played a role in the observed trend.

MORFAULT

24 N

KI

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DB

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0 50 100km

ANJIRASLOPE

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CHILTANCARBONATEPLATFORM

MIDDLEINDUS

LOWERINDUS

KARACHI

24 N

26 N

68 E66 E 70 E

68 E66 E 70 E

26 N

JEZAR FAULT

WAYARO FAULT

Fig. 5 - Cross section over Jezar Fault in westernMor Range illustrating contractional structures inboth footwall and hangingwall but overall netextension. J1-Lower Spingwar Member; J2-UpperSpingwar Member; J3-Loralai Member; J4-AnjiraMember; S-Sembar Formation.

EXAMPLES OF STRUCTURALINHERITANCE

Away from the western KFB, the lack of pre-LateCretaceous sediments precludes analysis of the earlyhistory of major faults based on outcrop data alone.Seismic data indicates that the Early Cretaceous doesnot show any major thickness changes above Chiltanas far west as Chapar. Although data quality is poor atthese depths this observation is taken to indicate thatthe Chiltan Platform lacks seismic scale syn-depositionalfaults and that the Mor Fault marks the eastern boundaryof the main rift zone. Subtle features of the Palaeocene-Eocene palaeogeography east of the Mor Fault howeversuggest that sub-seismic scale Jurassic faults werepresent and exerted an influence on the inversion patternsof the younger sediments.

Chapar-Andhar High

The Chapar-Andhar High is an isolated Eocenecarbonate platform in the eastern part of the Pab Provincedown dip from the main Eocene shelf-slope break tothe east (Fig. 2). It is unique in the Pab Province asbeing the only locality where shallow marine limestonesoverlie an erosionally truncated Rattaro section – ie itis the only known basinward location where the baseof depositional sequence T10 is represented by anunconformity. On the flanks of the high a distinctive

horizon of Late Palaeocene red shales is present on thecorrelative conformity at the base of T10. These areinterpreted as basinally reworked palaeosols derivedoff the Late Palaeocene exposure surface on the high.

Late Palaeocene uplift of the Chapar-Andhar High wasaccomplished by inversion of faults underlying itsflanks. Evidence for the presence of these deep-seatedfaults can be seen on the western, northern and southernmargins of the high. Here, progradational wedges ofKhude D limestones interfinger with Khude C basinalshales (Fig. 6). Each succeeding progradational wedgewas downflexed and onlapped by shales, building upto a point when the next wedge could prograde out.Downflexure around the margins of the high is due todifferential compaction between the Eocene platformlimestones on the high and the contemporaneous shalesin the basin

The axes of downflexure reflect the orientation of theinverted faults at depth. They are arranged in anorthogonal pattern with that on the western marginoriented NNW-SSE and those on the southern andnorthern margins oriented WSW-ENE. These arerespectively parallel and perpendicular to the faults ofJurassic age in the rift zone to the west and imply acontinued Jurassic control on sedimentation patternseast of the rift zone, albeit reduced in magnitude. Theorthogonal pattern identified is interpreted asrepresenting respectively the rift and transformorientations of the Jurassic rift.

Kirthar Range-Gorag Ridge

During the Late Cretaceous the Pab shelf prograded asfar west as the Kirthar Range/Gorag Ridge boundarybetween the Pab Province and the Kirthar Province.Apart from a brief basinward excursion of the shelfmargin in the Middle Eocene (Khude D) this stronglylinear NNW-SSE feature then remained the site of theshelf-slope break until Neogene times. Due to thedominance of Eocene outcrop along this zone, it is inthis interval that the shelf to slope transition is bestseen.

Along the Gorag Ridge, Eocene shelf carbonates passwestwards into fully basinal equivalents over a lateraldistance of less than 3km (Fig. 7). Although someelement of tectonic shortening is evident between thesefacies, it is not believed to be major. This rapid faciestransition and the strongly linear extent of the shelf-slope break suggests that the Kirthar Range/GoragRidge was underlain by a series of west-dipping highangle normal faults prior to Tertiary inversion.

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Bhit

At Bhit, the Dunghan Formation onlaps the RanikotFormation from north to south. Also depositional cyclesin the Nari Formation on the northeastern side of theBhit anticline thin southwards towards the central partof the fold subsidence appears to have been lower thanthe regional norm. These observations taken togetherindicate the presence of an extensional precursor to thepresent contractional Bhit Fault underlying the easternflank of the fold. This fault was partially inverted inthe Late Palaeocene to produce a broad submergenthigh, onlapped by the Dunghan Formation. During theEarly Oligocene deposition of the Nari Formation,maximum inversion of that part of the fold which hadthe highest original amount of extension accounted forthe observed pattern of sedimentary cycle thickness.

Laki Range

The Laki Fault on the eastern side of the Laki Rangeappears to have undergone successive phases ofinversion dating from the Late Palaeocene; four erosionalsurfaces downcut progressively through the hangingwall towards the fault indicative of inversionFigure-8. These repeated inversion events areresponsible for dramatic thinning of the Tertiary section

Fig. 8 - Schematic representation of Tertiary erosionalsurfaces downcutting towards Laki Fault. Not to scale.1. SBT10 Late Palaeocene; 2. SBT50 Early Oligocene;3. SBT60 Early Miocene; 4. SBT70 ?Pliocene.

towards the Laki Range culminating in exposure ofCretaceous Pab and Fort Munro Formations in thecentre of the range.

The Early Oligocene unconformity, SBT50 is one ofthe family of erosional surfaces that follows the patternof downcutting eastwards towards the Laki Fault. Itdivides the Kirthar Formation into upper and lowermembers. The fact that this partition is visible as farnorth as the Gaj River and possibly further suggests anorthward continuation of the Laki or related fault inthe subsurface to the east of the mountain front.

DISCUSSION

The examples cited above provide ample evidence thatTertiary and Cretaceous facies belts and some of themajor Late Tertiary fold structures in the southern KFBare not randomly distributed but instead are controlledby the positions of earlier extensional faults. Themajority of these faults are believed to be inheritedfrom Jurassic rifting. Observational data suggests theMor Fault on the eastern side of the Mor Range mayhave marked the boundary between a NE-SW (restored)Jurassic rift zone to the west, infilled with slope andbasinal sediments and a relatively stable platformal areato the east with minor faults parallel to and perpendicularto the rift zone (Fig. 4). Progressive deepening of theenvironment in which the Mor and Kulri Range Jurassicsediments were deposited may have been accomplishedby movement on the bounding faults of the rift zone.

The general organisation of facies belts in the KFBreveals that the rift zone is oriented parallel todepositional strike (NE-SW, restored). The orientationof the rift may itself have been inherited as it is parallelto the Precambrian Eastern Ghats trend in the basementof northern India. The cross-strike orientations identifiedon the Chapar-Andhar High are interpreted as transferfaults on the SE flank of the main rift, parallel tosubsequent transform offsets of the Mesozoic passivemargin.

The main inversion of the Jurassic faults took placeduring the Plio-Pleistocene collision event. Howeverearlier inversion took place dating from the LatePalaeocene. Late Palaeocene inversion is related toemplacement of the Bela Ophiolite onto the leadingedge of the plate. This event generated the T10 sequenceboundary and produced sea floor highs such as at Bhitand in the Laki Range. Seismic evidence shows thatsubstantial accommodation space was created throughloading of the passive margin at this time. Subsequentinfill of this marine ‘foreland basin’ is reflected by the

LAKI RANGEBADHRABHIT

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LOWER KIRTHAR

LOWER KIRTHAR 1

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SBT60

SBT50

SBT40 2

SBT30

LAKI

SBT20

SBT10

BARA

KHADRO

PABLAKHRA

DUNGHAN

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3

2

1

rapid westward thickening of the Laki/Khude Formations(Sequence T20). Ophiolite emplacement in the KFBtook place during first contact between India and Eurasiain the Indus Suture Zone. Later, pre-collisional Tertiaryinversion in the southern KFB is probably related totransfer of stress through the plate from the Himalayancollision zone.

In terms of the scale of the foldbelt, the effects ofinversion described above could all be produced byrelatively small scale reverse displacements on pre-existing normal faults, certainly not exceeding several100’s of metres. Given the 5-10km of structural reliefof the southern KFB, it is clear that this cannot beproduced by inversion alone. The consistent topographic(hence structural) elevation within the foldbelt suggestsa crustal scale (thick-skinned) process at work ratherthan fault-related basin inversion. Given there is noappreciable displacement across the mountain frontthen the deformation causing the uplift is restricted tothe fold belt. The surface deformation must howeverequate to a similar amount of deeper crustal shortening.Deep seismic or gravity/magnetic profiles would berequired to test this concept.

ACKNOWLEDGEMENTS

The authors wish to thank colleagues in Eni-LASMOPakistan Ltd for discussions which helped formulatethe ideas expressed in this paper. Notable amongstthese are Simon Beswetherick, Arshad Palekar, MujahidAli and Jerry Smart. The interpretations expressed inthis paper nevertheless are entirely the responsibilityof the authors.

REFERENCES

[1] Hedley, R., J. Warburton and J.D. Smewing, 2001.Sequence stratigraphy and tectonics in the KirtharFoldbelt, Pakistan. Proceedings of the SPE-PAPGConference, Islamabad, Pakistan, 2001, p. 1-11.[2] Smewing, J.D., J. Warburton, T. Daley, P.Copestakeand N. ul-Haq. Sequence stratigraphy of the southernKirthar Fold Belt and Middle Indus Basin, Pakistan.Geological Society, London, Special Publication 195,in press.[3] Bannert, D., A. Cheema, A. Ahmed and U. Schäffer,1992. The structural development of the Western FoldBelt, Pakistan. Geologisches Jahrbuch, Vol. B80, p.3-60.[4] Gnos, E., M. Khan, K. Mahmood, A.S. Khan, N.A.Shafique and I.M. Villa, 1998. Bela oceanic lithosphereassemblage and its relationship to the Réunion hot spot.Terra Nova, Vol. 10, p. 90-95.

[5] Patriat, P. and J. Achache, 1984. India-Eurasiacollision chronology and its implications for crustalshortening and driving mechanisms of plates. Nature,Vol. 311, p. 615-621.[6] Besse, J. and V. Courtillot, 1988. Palaeogeographicmaps of the continents bordering the Indian Ocean sincethe Early Jurassic. Journal of Geophysical Research,Vol. 92, p. 11791-11808.[7] Searle, M.P., R.I. Corfield, B. Stephenson and J.McCarron, 1997. Structure of the north Indiancontinental margin in the Ladakh-Zanskar Himalayas:implications for the timing and obduction of therSpontang ophiolite, India-Asia collision and deformationevents in the Himalaya. Geological Magazine, Vol.134, p. 297-316.[8] Treloar, P.J. and C.N. Izatt, 1993. Tectonics of theHimalayan collision between the Indian plate and theAfghan block: A synthesis. In: Treloar P.J. and M.P.Searle (eds) Himalayan tectonics. Geological Society,London, Special Publication 74, p.69-87.[9] Qayyum, M., A.R. Niem and R.D. Lawrence, 1996.Newly discovered Palaeogene deltaic sequence inKatawaz basin, Pakistan, and its tectonic implications.Geology, Vol. 24, p. 835-838.[10] Hailwood, E. and F. Ding, 1998. A supplementarypalaeomagnetic study of the Bela ophiolite, southwesternPakistan. Unpublished Core Magnetics Report No.CM9808.[11] Klootwijk, C.T., R. Nazirullah, K.A. De Jong, andH. Ahmed, 1981. A palaeomagnetic reconnaissanceof northeastern Baluchistan, Pakistan. Journal ofGeophysical Research, Vol. 86 B1, p.289-306.

ABOUT THE AUTHOR

John Smewing

John Smewing graduated withfirst class honours in EarthSciences and Chemistry fromUniversity of Leeds in 1971 andthen completed his Ph.D. at theOpen University in 1975 on theTroodos ophiolite in Cyprus.Following an early career inophiolite studies, John wasappointed Director of the Earth Resources Institute (ERI)of University of Wales, Swansea in 1980. His responsibilitieshere included managing a variety of field-based projectsin Oman, UAE, Madagascar, Turkey, Indonesia and Yemen.John's interest in Pakistan commenced in 1997 when ERIwere awarded a mapping contract in the SW Kirthar FoldBelt by Lasmo Oil Pakistan Ltd. Subsequent field work forLasmo has been carried out over abroad area of the southernKirthar Fold Belt and several 1:50,000 scale maps havebeen produced. The disparate lithostratigraphy of this areahas recently been formalized within a sequence stratigraphicframework.

Antonio Cernuschi

Antonio Cernuschi graduatedin Geological Sciences fromState University, Milano, Italy,in 1985. He has seventeenyears experience in the oil &gas industry as field andwellsi te geologist , andsubsequently as explorationgeophysicist. His main areasof experience are Continental Europe (France, Spain, Italy,Malta) Mediterranean offshore, East Africa onshore andoffshore, Asia and Far East (China, Malaysia, Vietnam,Mongolia, Pakistan), Australia. His most recent assignmentwas with AGIP China B.V. Beijing as Chief Geophysicist.He is currently Chief Geophysicist and Kirthar FoldbeltTeam Leader at Eni-Lasmo Pakistan in Karachi.

John Warburton

John received a First ClassHonors Degree in GeologicalS c i e n c e s f r o m L e e d sUniversity, UK in 1979 andcompleted his PhD inStructural Geology at SwanseaUniversity, UK in 1982. Hejoined BP Exploration in 1983as a Geo-scientist working inUK North Sea, Pakistan, Spain, Oman, Yemen, United ArabEmirates, Azerbaijan and Kazakhstan. In 1994 John joinedOil Search Ltd in Sydney, as Asset Manager for the PapuaNew Guinea Foldbelt Licenses and in 1997 was responsiblefor the company’s International New Venture assessments.In 1998 John joined LASMO as Exploration Project Managerfor North Africa & South Atlantic where he was responsiblefor onshore Algeria new business and for the company’sentry into deep water Morocco. From 1999 to mid 2002John was the Exploration & New Business Manager forLASMO Oil Pakistan Ltd. He was elected as the VicePresident of the Pakistan Association of PetroleumGeoscientists in 2001 and as Vice Chairman of the PetroleumExploration & Producing Companies Association Technical& Operations expert committee. John joined Roc OilCompany Ltd in Sydney in August 2002 where he is currentlythe Regional Manager – West Africa, responsible for allRoc Oil’s operated assets in Senegal, Angola and EquatorialGuinea and for the non-operated portfolio in Mauritania.John has numerous publications on tectonics, sequencestratigraphy and petroleum geology and he is an alumni ofCranfield Business School, UK.

Nazir Ul Haq

Nazir received his B.Sc. (Hons)and M.Sc. in Geology fromUniversity of Karachi in 1981.He joined Pakistan PetroleumLimited in 1982 wherein heworked in various disciplinesincluding mud engineering,welsite geology, filed geologyand reservoir geology for aboutten years. He joined LASMO Oil Pakistan initially asKadanwari Development Geologist in 1991 and later moved toKirthar Foldbelt team to work as Field and Exploration Geologist.