--> Abstract: Learning by the Bit: 15 Years of West Africa Deepwater Exploration, Development, and Production, by Kurt W. Rudolph; #90082 (2008)

Datapages, Inc.Print this page

Learning by the Bit: 15 Years of West Africa Deepwater Exploration, Development, and Production

Kurt W. Rudolph
ExxonMobil Exploration Company, Houston, TX

The past 15 years has witnessed the opening of a major new hydrocarbon province in the deep-water of West Africa, resulting in the discovery of over 20 billion oil-equivalent barrels of recoverable oil and gas. A significant part of this resource is already on production, contributing about 2.5 million barrels of oil per day. This intense period of exploration, development, and production provides a unique laboratory to understand Tertiary deep-water petroleum systems.

Several key technical learnings from the deep-water portions of the Aptian Salt Basin and Gulf of Guinea are summarized:
+ Rich source rocks with recent hydrocarbon generation driven by Neogene load have created robust petroleum systems. These are dominated by vertical migration into younger reservoirs.

+ Petroleum reservoirs are mostly slope channel complexes, with subsidiary distributive systems. Resulting lateral variability in sand development creates the opportunity for combination structural-stratigraphic traps with channel complexes draped across 3-way closures.

+ Generally excellent seismic imaging has facilitated the direct detection of reservoir and fluids. DHI/AVO analysis is a key technology with most discoveries associated with predrill anomalies.

+ Deep-water reservoirs have displayed excellent productivity and usually have good pressure connectivity. But complex reservoir heterogeneity can result in non-uniform sweep. This places a premium on accurate reservoir characterization, optimized development programs, and active surveillance (including 4D).

A significant future remains for this area as a prolific hydrocarbon province. However, exploration and production opportunities are becoming increasingly complex. Continued success will require ongoing improvements in technology and concepts to address seismic imaging, field size, and reservoir complexity challenges.

AAPG International Conference and Exhibition, Cape Town, South Africa 2008 © AAPG Search and Discovery