High Resolution Sequence Biostratigraphy of the Fim Kassar Oil Field, Kohat-Potohar Basin, Pakistan

Ali Jaffri, Oklahoma State University, School of Geology, Noble Research Center, Stillwater OK 74078, [email protected]

The Fim Kassar Oil Field is located in Pakistan and produces from an anticline of dolomitized fractured limestones of the Eocene Sakesar and Chorgali Formations. The field has been studied in detail because of its erratic production history. Gulf Oil Company first discovered this field but because of low productivity (20 barrels/day), sold it to the Oil and Gas Development Corporation of Pakistan Limited (OGDCL). OGDCL drilled three wells that were either prolific (4000 barrels/day) or came out dry (Fim-4). This erratic production is attributed to a lack of high-resolution subsurface data and a poor understanding of fracture orientation. Although detailed studies of fracture orientation have since been made, the depositional system and reservoir compartmentalization remain problematic. This study integrates several data sets (seismic, well logs, outcrop, and core) to create a sequence stratigraphic framework that will be used to understand reservoir compartmentalization. Calcareous Nannoplankton, Palynofossils, and Foraminifera will be used to identify keys-surfaces, delineate systems tracts, and identify bioevents that will be used for OGDCL’s future horizontal drilling operations in this field.