Reservoir Management in a Mature Carbonate Environment
Increasing oil demand requires greater efforts and imagination to develop hydrocarbons in increasingly difficult conditions: deep offshore, tight reservoirs, heavy oil, acid gas, etc. In this context, re-development of mature fields requires innovative solutions and often significant investments. A proper quantification of the stakes through a correct understanding of production mechanisms is necessary in order to optimise end-of-life developments and the timely implementation of the appropriate solution for curbing production decline. The Abu Al-Bukhoosh field, located offshore Abu Dhabi, has been producing for nearly 40 years. Total has been the operator since 1974. The successive phases of the field’s development over the past decades to further evaluate the field’s resources in response to its growing maturity will be described. Good volumetric sweep has been achieved in most of the reservoirs through extensive drilling, combination of water and gas injection and improved reservoir management by extensive focus on reservoir description, monitoring and modelling. Various IOR/EOR techniques were then implemented in subsurface (tertiary gas injection, horizontal drains), drilling (splitter well heads, multi lateral drilling), well activation and surface (process, water and gas management). Today, the field is definitely living a pivotal turn with decreasing oil stakes and higher investments for a second EOR generation and surface facilities revamping. The maturity level of the field provides new opportunities to start tackling relevant subsurface issues. Those issues concern the growing importance of secondary heterogeneities through field life, proper data acquisition strategy in highly swept environment or even an adapted use of emerging technologies. This is a matter of importance since the field resembles other giant carbonate fields of the United Arab Emirates and the Middle East, which will reach maturity in a few decades from now.
AAPG Search and Discovery Article #90077©2008 GEO 2008 Middle East Conference and Exhibition, Manama, Bahrain