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

Ali Jaffri
Oklahoma State University, Stillwater, OK

High impact biostratigraphy is the integration of high-resolution sequence biostratigraphy and multidisciplinary work to achieve business goals. This study applies high impact biostratigraphy to the Fim Kassar Oil Field in Pakistan. Fim Kassar 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 unusual 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. 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 predict subsurface occurrence of fracture prone beds. Calcareous Nannoplankton, Palynofossils, Foraminifera and others microfossils will be used to identify key-surfaces, delineate systems tracts, and identify bioevents that will be used to biosteer OGDCL's future horizontal wells in this field.