A preliminary account of the Middle Jurassic plays in Najafpur Village, southeastern Hazara, Khyber Pakhtunkhwa, Pakistan
Keywords:
Jurassic; Grainstones; Samana Suk; Hazara; Hydrocarbon prospects.Abstract
The southeast Hazara forms a part of Himalayan fold and thrust belt of Pakistan. The study area is covered by Mesozoic-Cenozoic age rocks that have undergone severe deformation and is characterized by the formation of complex fold and thrust assemblages. The structures include northwest and southeast verging thrust systems with associated folds. Two deformational events separate the structures in the area. The structures in the northwestern quadrant display southeast facing direction whereas the southeastern quadrant is dominated by structures that dip towards southeast. The general trend of the structures is northeastsouthwest and that attributes to the northwest-southeast contractile deformation. The trend of the structures depicts that stresses were directed from northwest. The folds are found to be tight to overturned and the cores of the folds are usually occupied by competent Samana Suk Formation. The organic rich horizons were observedin the eld within the Formation, the TOC of which was calculated as 0.28%. Microfacies analysis reveals well sorted and well-rounded ooidal-peloidal grainstones and packstones as well as dolomitized and fractured wackestones and mudstones. The diagenetic signatures include fracturing and dolomitization depicting its source and reservoir quality for a hydrocarbon prospect.
References
Beard, D.C., Weyl, P.K., 1973. The influence of texture on porosity and permeability on unconsolidated sand. Bulletin of American Association of Petroleum Geologist, 57, 349-369.
Chilingar, G.V., Terry, R.D., 1964. Relationship between porosity and chemical composition of carbonate rocks. Petroleum Engineering, 54, 341-342.
Cotter, G.D.P., 1933. Geology of part of Attock district west of longitude 72° 45' E. Geological Survey of India Memoirs, 55 (2), 63-161.
Dunham, R.T., 1962. Classification of carbonate rocks according to depositional texture. In: Ham, W.E. (Eds.), Classification of carbonate rocks. Bulletin of American Association of Petroleum Geologists Memoir, 1, 108-121.
Flügel, E., 2004. Microfacies of carbonate rocks, analysis, interpretation and application. Springer-verlag, 976.
Fraser, H.J., 1935. Experimental study of the porosity and permeability of clastic sediments. Journal of Geology, 43
Ghazanfar, M., Chaudary, M.N., Pervaiz, K., Qayyum, M., Ahmed, R., 1990. Geology and Structure of Kuza-DungaGali-Ayubia Area, Hazara-Potwar Basin with reference to Hydrocarbon Prospects of Attock Hazara Fold and Thrust Belt. Pakistan Journal of Hydrocarbon Research, 2(2)
Hussain, H.S., Fayaz, M., Haneef, M., Hanif, M., Jan, I.U., Gul, B. 2013. Microfacies and diagenetic fabric of the Samana Suk Formation at Harnoi Section, Abbottabad Khyber Pakhtunkhwa, Pakistan. Journal of Himalayan Earth Sciences, 46 (2), 79-91.
Izzat, C.N., 1993. Variation in thrust front geometry across the Potwar Plateau and Hazara/ Kalachitta Hill Ranges, Northern Pakistan. Unpublished PhD thesis, Imperial College of Science, Technology and Medicine, London.
Kazmi, A.H., Rana, R.A., 1982. Tectonic map of Pakistan. Geological Survey of Pakistan
Krumbein, W.C., Monk, G.D., 1942. Permeability as a function of the size parameters of unconsolidated sands. Transactions of the Petroleum Division, American Institute of Minerals and Metallurgical Engineering, 1492, 1-11.
Latif, M.A., 1970. Explanatory notes on the geology of Southeastern Hazara to accompany the revised geological map:
Wein Jb. Geol. B.A. Sonderban, 15, 5-20. Masood, H., 1989. Samana Suk Formation depositional and diagenetic history, Kashmir Journal of Geology, 6-7, 151-161.
McDougall, J.W., Hussain, A., 1991. Fold and Thrust Propagation in the Western Himalaya based on a balanced cross section of the Surghar Range and Kohat Plateau, Pakistan. Bulletin of American Association of Petroleum Geologists, 75, 463-478.
Middlemiss, C.S., 1896. The Geology of Hazara and Blank Mountains. Geological Survey of India Memoirs, 26, 302.
Middlemiss, C.S., 1896. The Geology of Hazara and the Black Mountains: Geological Survey of India Memoirs, 26(1), 1-290.
Nizami, A.R., Sheikh, R.A., 2009. Microfacies Analysis and Diagenetic Settings of the Middle Jurassic Samana Suk Formation, Sheikh Budin Hill Section, Marwat Range,
Trans Indus Ranges, Pakistan. Geological Bulletin Punjab University, 44, 69-84.
Pogue, K.R., 1994. Stratigraphic and structural framework of Himalayan foothills, Northern Pakistan. Ph.D. thesis, Oregon State University, USA.
Pryor, W.A., 1973. Permeability-porosity patterns and variations in some Holocene sand bodies. Bulletin of American Association of Petroleum Geologists, 57, 162-189.
Qureshi, M.A., Baig, S., Munir, M.H. 1997. Reconnaissance microfacies analysis of the Upper Jurassic Samana Suk Formation, Northern Hazara Pakistan. Geological Bulletin, Punjab University, 31-32.
Rogers, J.J., Head, W.B., 1961. Relationship between porosity median size, and sorting coefficients of synthetic sands. Journal of Sedimentary Petrology, 31, 467-470.
Sheikh, R.A., Qureshi, M.K.A, Ghazi, S., Masood, K.R. 2001. Jurassic carbonate shelf deposition Abbottabad District Northern Pakistan. Geological Bulletin, Punjab University, 36, 49-62.
Waagen, W., 1872. Rough section showing the relations of the rocks near Murree (Mari) Punjab. Geological Survey of India Records, 5, 15-18.
Wynne, A.B., 1873. Notes from progress report on the geology of parts of the upper Punjab. Geological Survey of India Records, 6 (3), 59-64.
Wynne, A.B., 1875. Notes on the Tertiary zone and underlying rocks in the northwest Punjab. Geological Survey of India Records, 10(3), 107-132.
