Lithofacies and Microfacies Analysis of Kohat Formation, Panoba Village, Kohat Sub Basin, Pakistan (T-1447) (MFN 8323)

Abstract

The microfacies and lithofacies analysis of Kohat Formation was carried out at Panoba Range, for detailed stratigraphical and micropalentological studies to determine the age and depositional environment of the formation. To analyze the microfacies, lithofacies and depositional environment and diagenetic fabric, twenty outcrop samples were studied from limestone unit of Kohat Formation at Panoba Range. Kohat Formation shows variable thickness having thin to thick beds and mainly composed of nodular limestone with intercalations of thinly laminated shale. Based on lithology and primary sedimentary features, the Kohat Formation is divided into eight different lithofacies. The Kohat Formation contained abundant varieties of larger foraminifera belonging to the genera Nummulites, Assilina and Alveolina. Based on outcrop and petrographic data, six microfacies have been identified, i.e., Nummulitic Packstone Microfacies (KF-MF-1), Algal-Miliolid Wackstone-Packstone Microfacies (KF-MF-2), Bioclastic Packstone Microfacies (KF-MF-3), Bioclastic Wackestone Microfacies (KF-MF-4), Nummulitic Grainstone Microfacies (KF-MF-5) and Bioclastic Mudstone Microfacies (KF-MF-6). The characterization of these facies supports deposition in a shallow marine environment.The diagenetic fabric of Kohat Formation consisting of neomorphism, dissolution, micritization indicates meteoric to deep burial environment of diagenesis