Opportunistic Pressure Data Gathering Campaign During Production Shut Down—Added Insight Into the Water Flood Response and Pressure Connectivity in a Highly Heterogeneous Clastic Reservoir in North Kuwait

摘要

Upper Burgan is a sandstone reservoir in North Kuwait, which is a depletion drive reservoir predominantly, with a very weak aquifer support. The reservoir has cumulatively produced about 7% of oil in place since its discovery. Almost 90% of production in the historical past came from the crestal area leading to a rapid decline in reservoir pressure. The initial reservoir pressure was about 3800 psia and it is continuously declining to bubble point pressure. Recently water flood has been initiated at three of the injectors in the crestal area to reverse the trend of pressure decline. Pressure monitoring is the key for the monitoring heterogeneous Upper Burgan reservoir, currently under water flood. This has been achieved in three ways during past 5 years: Time lapse SBHP monitoring; isochronal full field pressure surveys during reservoir shutdown and PBU/PFO /RFT/ data integration with PLT & Production tests. Extensive data gathering has enabled the team to enhance the water flood response. Additionally, smart maps using OFM have also been created as tracking tools. The pressure monitoring & analysis has helped in effective water flood management as well as sustaining the production rates for this challenging heterogeneous reservoir. Also, the extensive data acquired and analyzed has added value to the comprehensive channel description, reservoir continuity and simulation model update for this reservoir. The objective of the paper is to share the approach adopted by us and experiences gained during last 5 years of water flood monitoring in North Kuwait.