Publications

The Krisna Field is operated by Pertamina/IIAPCO within the Offshore Southeast Sumatra Production Sharing Contract. It is located in the Java Sea approximately 125 Km Northwest of Jakarta. The main oil producing reservoir in the Krisna Field is the Lower Batu Raja forma- tion, a carbonate build-up.The first platform producing from the Krisna Lower Batu Raja reservoir was placed on production in November 1980, but reservoir development was continued from additional platforms through August 1982. An early decline in well productivity, caused by a rapid decline in reservoir pressure, indicated that some form of pressure maintenance would be required to optimize reserves recovery. Following a favourable response to a pilot water injection project initiated in August 1982, a reservoir simulation study was commissioned in December 1982, with the objective of defining the optimum development strategy for the reservoir. Lemigas was selected to conduct the study. Based on the recommendations of the model study, a full scale waterflood has been initiated.This paper reviews the development and performance of the Krisna Lower Batu Raja reservoir, outlines the pilot water injection project, discusses the reservoir model study, and describes the full scale waterflood implemented to op- timize oil recovery.