Facies Analysis, Sequence Stratigraphy and Diagenetic Studies of the Jurassic Carbonates of the Kohat Basin, Northwest Pakistan: Reservoir Implications

作     者：Emadullah KHAN Abbas Ali NASEEM Suleman KHAN Bilal WADOOD Faisal REHMAN Maryam SALEEM Mubashir MEHMOOD Waqar AHMAD Zubair AHMED Tahir AZEEM Emadullah KHAN;Abbas Ali NASEEM;Suleman KHAN;Bilal WADOOD;Faisal REHMAN;Maryam SALEEM;Mubashir MEHMOOD;Waqar AHMAD;Zubair AHMED;Tahir AZEEM

作者机构：Department of Earth SciencesQuaid-e-Azam UniversityIslamabad 45320Pakistan Department of GeologyAbdul Wali Khan UniversityMardan 23200Pakistan Department of GeologyUniversity of PeshawarPeshawar 24420Pakistan State Key Laboratory of Continental DynamicsDepartment of GeologyNorthwest UniversityXi’an 71006China Department of GeologyUniversity of SwabiSwabi 23561Pakistan Department of Earth&Environmental SciencesBahria UniversityIslamabad 44000Pakistan Department of Earth&Atmospheric SciencesUniversity of AlbertaEdmonton T6G 2R3Canada 

出 版 物：《Acta Geologica Sinica(English Edition)》 (地质学报（英文版）)

年 卷 期：2022年第96卷第5期

页      面：1673-1692页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

主　　题：porosity diagenesis reservoir Samana Suk Formation Kohat Basin 

摘      要：The present study deals with the depositional facies, diagenetic processes and sequence stratigraphy of the shallow marine carbonates of the Samana Suk Formation, Kohat Basin, in order to elucidate its reservoir quality. The Samana Suk Formation consists of thin to thick-bedded, oolitic, bioclastic, dolomitic and fractured limestone. Based on the integration of outcrop, petrographic and biofacies analyses, the unit is thought to have been deposited on a gentle homoclinal ramp in peritidal, lagoonal and carbonate shoal settings. Frequent variations in microfacies based sea-level curve have revealed seven Transgressive Systems Tracts(TSTs) and six Regressive Systems Tracts(RSTs). The unit has undergone various stages of diagenetic processes, including mechanical and chemical compaction, cementation,micritization, dissolution and dolomitization. The petrographic analyses show the evolution of porosity in various depositional and diagenetic phases. The fenestral porosity was mainly developed in peritidal carbonates during deposition,while the burial dissolution and diagenetic dolomitization have greatly enhanced the reservoir potential of the rock unit, as is further confirmed by the plug porosity and permeability analyses. The porosities and permeabilities were higher in shoal facies deposited in TSTs, as compared to lagoonal and peritidal facies, except for the dolomite in mudstone, deposited during RSTs. Hence good, moderate and poor reservoir potential is suggested for shoal, lagoonal and peritidal facies,respectively.