Download - Free Documents

//
Oldest reservoirs of Cambrian, Permian lightly tested in Potwar basin, Pakistan Save this
page
Click to read and S bscribe today For past issues click here.
This Weeks Iss e
Save Article Instructions Close
Olde
e e oi of Camb ian, Pe mian ligh l e ed in Po a ba in, Paki an
In Pakistan the first oil well was drilled near an oil seep at Kundal in the Potwar basin in , just
years after the Drake well in Pennsylvania. Since then in spite of a low number of wells
drilled, several oilfields have been discovered.
ogj.com/ /oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan.saveArticle
/
Permian lightly tested in Potwar basin. to the north by the Main Boundary Thrust. and to the
west by Kalabagh transform fault. Dhurnal. Chak Naurang. stresses the need for more
concentrated effort on these older reservoirs. . Po a geolog The Potwar basin is bounded to
the south by Salt Range escarpment.// Oldest reservoirs of Cambrian. Rajian. Ltd. to the east
by the Jhelum transform fault.saveArticle / .Save this page Yet the Potwar basin still has not
acquired the status of a mature basin as all of its potential reservoirs either have not been
Click here to enlarge image reached or tested. as in Missa Keswal.com/
/oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan. which either have not
been reached or missed production tests in the first holes. MissaKeswal. The oldest
reservoirs of Cambrian and Permian ages have been found in the quotthrusted anticlinal
playquot of Adhi. Balkassar. Pakistan . ogj. The recent commercial oil discovery in Permian
Tobra sandstone in Missa Keswal well by Oil amp Gas Development Corp. Main production
has been from Paleogene carbonate and Jurassic clastic reservoirs. Joya Mair. and Kal oil
fields Fig.
Save this page Infracambrian evaporites of unknown true thickness were deposited in the
Potwar basin in restricted environments caused by carbonate banks developed over the east
bank of the Jhelum reentrant. Permian lightly tested in Potwar basin. collectively known as
the Jhelum Group. Click here to enlarge image Rocks of Cambrian age. are extensively
exposed along the southern boundaries of the KohatPotwar basin in the Salt and Khisor
Ranges and encountered in subsurface in the Potwar basin in several wells. north of present
KalaChitta and Margala Ranges. The Jhelum Group represents different cycles of
sedimentation beginning with mixed nonmarine and marine sandstone. and ogj.// Oldest
reservoirs of Cambrian. .com/
/oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan. where open marine
conditions prevailed Fig. Pakistan . along Precambrian basement lineaments which isolated
Potwar from Kashmir and Hazara.saveArticle / .
on wireline logs. the lower Nilawahan Group and the upper Zaluch Group. and Table . and
the latter including marine rocks Fig.com/
/oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan. The Permian rocks of
the Salt Range and TransIndus Ranges are m thick and can be further subdivided into two
groups. Click here to enlarge image ogj. and on seismic sections. Pakistan .Save this page
ending with the lagoonal Bhaganwalla/Khisor formation. Click here to enlarge image An Early
Permian unconformity marks the onset of fluvioglacial to glaciomarine/lacustrine conditions.
Permian lightly tested in Potwar basin. the former predominantly of continental origin.
Significant lithological change preceding and following the Cambrian makes the upper and
lower contacts easy to recognize in the field.// Oldest reservoirs of Cambrian.saveArticle / .
It is associated with a major EW thrust fault. tested gravity oil from Tobra sandstone. Adhi.
dipmeter logs. km. locally high but normally low to moderate amplitude. The top Salt
Range/Base Cambrian reflector is fairly strong and consistent. eroded down to MioPliocene
Chinjis. ogj. Balkassar. Permian lightly tested in Potwar basin. consistent seismic reflector. it
tested gravity oil from Cambrian Khewra sandstone and Tobra sandstone. Fig. with low
frequency and strong amplitude. and seismic sections. with m of vertical closure. and gravity
oil from Paleogene Sakessar limestone. and Joya Mair oil fields. It is a NESW trending.
eroded down to Chinjis. especially in East Potwar.Save this page Permian rocks have been
encountered in several wells drilled in the Potwar basin. gravity oil from Cambrian Khewra
sandstone. Pakistan .com/
/oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan. by . is a
representative seismic section of Upper Indus/Potwar basin.saveArticle / . by . discovered
this field in East Potwar in . drilled to . and on trend with Karsal. Adhi oil field Pakistan
Petroleum Ltd. It is reflected at the surface as an EW trending narrow anticline covering .//
Oldest reservoirs of Cambrian. Click here to enlarge image Top Tobra is a strong. At top
Eocene level it is by . In addition to the primary Eocene Chorgali limestone reservoir. Chak
Na ang oil field OGDC discovered this field in the Potwar basin in . Cambrian seismic facies
are characterized by variable. km with m of vertical closure. km with m of amplitude. very
narrow steep anticline. In general. m. The base Permian unconformity is quite easy to pick
on densityneutron logs.
Pakistan . It is a narrow NESW trending structure with surface expression by .// Oldest
reservoirs of Cambrian. the latter providing the permeability through which the hydrocarbons
are produced. micritization. with energy conditions ranging from moderate to high.
calcareous sandstones. Missa Keswal. chemical compaction. Based on the lithologic and
biotic differences. . and secondary porosity development. The important diagenetic
processes recognized are bioturbation. and kerogen type. dissolution. At surface it is an EW
syncline. A m thick micritic dolomite unit is very distinctive and traceable over a long distance
in the study area. discovered this field in in the triangle zone in the foreland belt of the North
Potwar Deformed Zone. cementation. siltstone. while at Paleogene and Permian subsurface
levels it is an anticline with fourway dip closure. A geological and petrophysical study of
cores from the Adhi. The Dhurnal well tested . latter enhanced by faults. and wells by Core
Laboratories has divided the Tobra formation into six lithofacies including sandstone. and
shallow subtidal environments. dolomitization. silicification. Chhidru. Mi a Ke al oil field
OGDC discovered this field in East Potwar in . All hydrocarbons are stored in fractures. and
bioturbated argillaceous sandstone. Bhaganwalla. This unit can be identified as a potential
reservoir.saveArticle / . while the Wargal formation is a cliffforming massive carbonate unit.
poorly bedded sandstone. ogj. km. which can further be divided into microfacies. drilled in .
pebbly sandstone. Proven source rock Patala and potential source rock Salt Range are
extremely rich sources for liquid hydrocarbons. There is little if any intergranular hydrocarbon
storage. sandy conglomerate. Hydrocarbon Development Institute of Pakistan measured and
sampled in detail a m thick Wargal formation along the Chhidru Nala stream in the Western
Salt Range. So ce ock Marine and restricted marine shales of the Paleocene Patala
formation are the proven source rocks in the Potwar basin. Permian lightly tested in Potwar
basin. estimated visual carbonization scale.com/
/oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan. Cambrian Kussak
had also tested positive. and Khewra sandstone gravity. eroded down to Chinjis. and Amb
formations are mainly slopeforming. the Wargal formation has been divided into seven
lithologic units. b/d of oil from Permian Wargal limestone. Based on weight percent organic
carbon. Tobra sandstone was not tested in this well. intertidal. Cambrian Jutana dolomite.
which were deposited in marine nearshore. potential source rocks include shallow
marineestuarine shales of Chhidru Late Permian and Sardhai Early Permian and restricted
marine shales of the Salt Range Precambrian formation. tested commercial oil production
from the Tobra sandstone reservoir. Pe mianCamb ian e e oi The Permian. There are
indications that hydrocarbons were generated in Khisor Cambrian source rocks.Save this
page Dh nal oil field Occidental Petroleum Corp. fracture fillings. Missa Keswal has been an
oil producer from Paleogene SakessarLockhart.
B. October . It is recommended to drill and test Paleozoic in general and CambrianPermian
reservoirs in particular. with fining upward units from waning flows. Diagenesis has had a
significant effect. Pakistan . poorly bedded sandstone. Predrilling predictability can be
attempted to assess such parameters. especially in East Potwar where these reservoirs
occur at shallower depths as a result of Mesozoic being eroded out. October .quot
OGJ...Save this page These lithofacies form a thinly interbedded succession in which small
scale fining upwards units can be recognized. A. with average porosity . .. early hydrocarbon
emplacement. with geometric average permeability of . or stimulation practices.quot
published by Pakistan Petroleum Ltd. md. and laminated rippled sandstone. Kadri. . and
Quadri..saveArticle / . quotA Geological and Petrophysical Study of Cores from Wells Adhi
and . Karachi.quot Core Labs. The rate of permeability and porosity decline with increasing
depth can be significantly reduced by grain coats and rims. Permian lightly tested in Potwar
basin.J. V. in Adhi and . Martin. and geometric average permeability . Although permeability
and porosity decrease with depth. in Adhi. md and .com/
/oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan. and the occurrence
of ice rafted laminate facies in the Adhi well probably represents glacial outwash sediments
deposited into a marine basin. wellbedded sandstone. Lateral continuity in adjacent wells
and outcrops argues against considering deposition as a meandering channel system/point
bars. These are red colored. Three lithofacies are identified from Adhi in the Cambrian
Khewra formation. . Generally a glacial environment exists for Tobra. quotMicrofacies
Analysis and Porosity Development in Wargal Formation Permian Exposed at Chhidru
Nala.// Oldest reservoirs of Cambrian. respectively. May . G. Compaction is minimized in the
Khewra formation by early precipitation of quartz overgrowth cements. as a result of more
accurate delineation of subsurface structural crests by use of sophisticated seismic
technology.quot SPEPAPG Annual Technical Conference. anomalously high values can
occur at depth. md in Adhi. I. considered to have been deposited as high energy braided
stream deposits or as unconfined sheet flows accumulated in distal alluvial fan/sand flat
environments.H. quotPetroleum Geology of Pakistan. Reservoir characteristics include poor
to moderate average porosity of . September ogj. Both the Tobra and Khewra formations are
susceptible to formation damage through adverse reactions between certain sensitive
minerals and particular drilling. and shallow development of fluvial overpressure. Reservoir
characteristics are poor to moderate. Cheema. quotAnatomy of success in oil and gas
exploration in Pakistan. Refe ence . The time of hydrocarbon generation. Quadri. . migration.
Western Salt Range. Wellbedded sandstone lithofacies at the top of the Khewra formation
have the best reservoir quality. Quest. Recommenda ion The prospectivity of the Potwar
basin has been significantly enhanced by discoveries of hydrocarbons in the deeper
Paleozoic reservoirs. completion. although it is subordinate to depositional texture as a
control on porosity and to a lesser extent on permeability. and the presence of suitable
structural and stratigraphic traps need further study in search for oil in CambrianPermian
reservoirs.N. These are believed to have been deposited within a shallow marine
environment from shortlived densityturbiditic underflows. Pakistan..
Pakistan . Quadri vnquadrihotmail. go to h p// . .e e oi ofcamb ianpe mianligh l . retiring as
acting general manager of exploration after nearly years service. Jeelani Quadri has been
regional manager of the public sector of OGDC.com served Oil amp Gas Development Corp.
Permian lightly tested in Potwar basin. to enlarge image To access this Article. After
retirement from active exploration.com/con en /ogj/en/a icle /p in / ol me/i e/e plo a ionde
elopmen /olde . the UK. Islamabad. and US geoscientists and visited China. V.Save this
page revised May .com/
/oldestreservoirsofcambrianpermianlightlytestedinpotwarbasinpakistan. Click here Norway.
Norad. and Cida petroleum to enlarge workshops. Bloch.N.e edinpo a ba inpaki an.
Canadian.h ml ogj. Canada.. He was also exploration advisor to Marathon Pakistan
Petroleum and Pakistan Shell Oil Co. The a ho Mrs.. Norwegian. He has a BSc in geological
and physical sciences from Queens University and an MSc in geological sciences from the
University of Toronto. Click here S.M. quotAnomalously High Porosity and Permeability in
Deeply Buried Sandstone Reservoirs. February . OGDCL archives. et al.ogj.G. S.// Oldest
reservoirs of Cambrian.saveArticle / . he served in the oilfield equipment and services
industry for about years. from its inception.quot AAPG Bull. She has an MS in geophysical
prospecting from the University of Michigan as a FulbrightSmith image Mundt scholar.. She
carried out several technical studies in collaboration with Russian. and the US as Pakistani
delegate to Unido.