Reservoir Characterization from Lucapa Field, Angola: Advanced Methods for the Reservoir Identification, Delineation & Connectivity Estimation

Jay Byers
Southern Africa - New Field Development, Chevron International Exploration & Production Company, Houston, TX

Lucapa field is a large Miocene-age oil field located in Block 14, Angola. The field was discovered in 2006 with the Lucapa-1 exploration well. Water depths in the field area range from 3000'-6000'. The field is adjacent to the Congo River Canyon and is characterized as a deepwater mid-slope turbiditic channel deposit consisting of reservoirs throughout the Middle Miocene section. Depth to the primary reservoir is 7000-8000 feet (2000'-4000' DBML).

Perhaps the most complex objectives faced during the characterization of the reservoirs in Lucapa field and likely all turbiditic reservoirs are: 1) identification of the reservoirs, 2) delineation of the reservoirs, and 3) quality of the reservoirs, and 4) connectivity of the reservoirs.

In this reservoir characterization effort, rock property information was integrated and used to guide the interpretation of the internal architecture of the reservoir elements to a degree not present in past work. The results using this integrated approach were superior to previous non-integrated methods and led to superior static reservoir models in which channel element interfaces did not cross viable reservoir-quality rock.

At the conclusion of the reservoir model grid construction, several lessons learned included:
1. Correct and detailed characterization of the reservoir is paramount to the success of any project due to the importance of the results being used in the construction of the static reservoir model.
2. Prior to any data interpretation, establish as complete and reliable stratigraphic and structural frameworks as possible. Edit and update the frameworks as required as interpretation progresses.
3. Utilize seismic attribute-driven reservoir geobodies interactively when interpreting seismic data to insure that channel and channel element interfaces don’t cross viable reservoir.

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