Microfacies and diagenetic-fabric of the Samana Suk Formation at Harnoi Section, Abbottabad, Khyber Pakhtunkhwa, Pakistan
Abstract
A detailed geological investigation of the Samana Suk Formation at the Harnoi section, District Abbottabad, Pakistan was carried out to elaborate its microfacies settings and diagenetic features. Thirty one samples were studied from a 60m thick section and three microfacies with five sub microfacies identified. The microfacies includes; 1. Grainstone microfacies (ooid grainstone, peloidal grainstone and intra-ooid grainstone as sub microfacies), 2. Mudstone microfacies (partially dolomitized mudstone and dolomicrite as sub microfacies) and 3. Bioclastic wackstone microfacies. The depositional environment depicted is beach, bars and shoal for grainstone microfacies, restricted lagoon for mudstone microfacies and inner to mid ramp for bioclastic wackestone microfacies. A variety of cement morphologies from early to late diagenetic phases have been identified. Micrite and spar have been developed in different diagenetic settings. Diagenetic features like stylolites, calcite veins, fractures, deformation and ferroancalcite formation have been observed. Varying degree of dolomitization has been developed at various levels within the formation. The Samana Suk Formation at the Harnoi section represents inner to mid-ramp environment of deposition.
References
Calkins, J.A., Offield, T.W., Ali, S.T., 1969. Geology and mineral resources of southern Hazara district, West Pakistan and part of western Kashmir. United States Department of State and Government of Pakistan project report, 43, 92.
Donahue, J., 1969.Genesis of oolite and pisolite grains. Journal of Sedimentary Petrology, 39, 1399-1411.
Dunham, R.J., 1962.Classification of carbonate rocks according to depositional texture. In: Ham, W.E. (Ed.), Classification of carbonate rocks. American Association of Petroleum Geologists Memoir, 108-121.
Fatmi, A.N., Hyderi, I.H., Anwar, M., 1990. Occurrence of the Lower Jurassic Ammonoid Genus Bouleiceras from the Surghar Range with a revised nomenclature of the Mesozoic rocks of the Salt Range and Trans Indus Ranges (Upper Indus Basin). Geological Bulletin Punjab University, 25, 38-46.
Flügel, E., 2004. Microfacies of carbonate rocks. Springer-Verlag, Berlin, Heidelberg, New York.
Folk, R.L., 1959. Practical petrographic classification of limestones. Bulletin, American Association of Petroleum Geologists, 43, 1-38.
Folk, R.L., 1962. Spectral subdivision of limestone types. In: Ham, W. E. (Ed.), Classification of carbonate rocks. American Association of Petroleum Geoscientists Memoir, 1, 62-84.
Folk, R.L., 1965. Some aspects of recrystallization in ancient limestones. Society of Economic Paleontologists and Mineralogists Special Publication, 13, 14-48.
Gardezi, A.H., Ghazanfar, M., 1965. Change of facies at the base of Jurrasic in Hazara. Geological Bulletin University of Punjab, 5, 53-56.
Halland, M.D., Riaz. M., 1988. Stratigraphy and structure of southern Ghandghar Range, Pakistan. Geological Bulletin University of Peshawar, 21, 1-14.
Iqbal, M.W.A., 1972. Bivalve and gastropod fauna from Jherruk-Lakhra-Bara Nai (Sindh), Salt Range (Punjab) and Samana Range (KPK). Geological Survey of Pakistan Memoir, 9, 104.
Latif, M.A.,1970. Explanatory notes on the geology of southern Hazara, to accompany the revised Geological Map. Jahrbuch der Geologischen Bundesanstalt, Sonderband 15, 5-20.
Masood, H., 1989. Samana Suk Formation depositional and diagenetic history, Kashmir Journal of Geology, 6 and 7, 151-161.
Mensink, V., Mertmann, D., Ahmad, S., 1988. Facies Development during the Jurassic of the Trans Indus Ranges, Pakistan. Neues Jahrbuch für Geologie und Paläontologie, Monatshefte, 3, 153-166.
Middlemiss, C.S., 1896. The geology of Hazara and Black Mountains. Indian Geological Survey Memoir, 26, 1-302.
Nizami, A.R., Sheikh, R.A., 2009. Microfacies analysis and diagenetic settings of the middle Jurassic Samana Suk Formation, Sheikh Budin Hill section, Trans Indus Ranges, Pakistan. Geological Bulletin Punjab University, 44, 11-25.
Qureshi, M.K.A., Butt, A.A., Ghazi, S., 2008. Shallow shelf sedimentation of the Jurassic Samana Suk Limestone, Kala Chitta Range, Lesser Himalayas, Pakistan. Geological Bulletin Punjab University, 43, 1-14.
Scholle. P.A., Ulmer-Scholle, D.S., 2003. A Color Guide to the petrography of carbonate rocks. American Association of Petroleum Geoscientist Memoir, 77, 459.
Schroeder, J.H., 1972. Fabrics and sequences of submarine carbonate cements in Holocene Bermuda cup reefs. Geologische Rundschau, 61, 708-730.
Tucker, M.E., Wright, V.P., 1990. Carbonate sedimentology. Blackwell Scientific Publication, London.
Waagan, W., Wynne, A.B., 1872. The Geology of the mount Sirban in the upper Punjab. Geological Survey of India Memoir, 9, 331-350.
Wilsons, J.L., 1975. Calcareous facies in geological history. Springer-Verlag, Berlin, Heidlberg, New York.
