Enhanced Recovery from a Fractured Reservoir Using High Impact Biostratigraphy: a Case Study from the Fim Kassar Oil Field, Pakistan

Abstract

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 a fractured reservoir from the Fim Kassar Oil Field in Pakistan. Fim Kassar produces from fractured dolomites of the Eocene Sakesar and Chorgali Formations. Gulf Oil Company first discovered this field but because of low productivity, sold it to the Oil and Gas Development Corporation of Pakistan Limited (OGDCL). OGDCL drilled three wells that were either prolific or came out dry. This erratic production is attributed to poor understanding of fracture occurrence in the sub-surface. Although studies of fracture orientation have been made, the prediction of fracture prone beds remains problematic. Enhanced recovery from this fractured reservoir is contingent upon a better understanding of fracture occurrence in the subsurface. This study integrates several data sets to create a sequence stratigraphic model which is used to predict subsurface occurrence of fracture prone beds. Microfossils identify key-surfaces, delineate systems tracts, and "fingerprint" payzones which are used to design a biosteering program for future horizontal wells in this field.