The Shenandoah-2 appraisal well in the deepwater Gulf of Mexico has encountered more than 1,000 net ft of oil pay with “reservoir rock and fluid properties of much higher quality than previously encountered by industry in Lower Tertiary discoveries,” said Anadarko Petroleum Corp.
Shenandoah-2, having tapped multiple Lower Tertiary-aged reservoirs, is a potentially giant development that will require further appraisal and is one of the company’s largest oil discoveries in the gulf, Anadarko added.
Shenandoah-2 went to 31,405 ft in 5,800 ft of water on Walker Ridge Block 51 more than 1 mile southwest and 1,700 ft structurally downdip from the early 2009 Shenandoah-1 discovery well that cut more than 300 net ft of Inboard Lower Tertiary oil pay on Block 52 (OGJ Online, Feb. 5, 2009).
Shenandoah-2 was drilled to test the downdip extent of the accumulation, and the targeted sands were full to base with no oil-water contact.
Bob Daniels, Anadarko senior vice-president deepwater and international exploration, said, “With ownership in the successful Shenandoah wells, the adjacent Yucatan prospect, and the very encouraging results from the nearby Coronado well, Anadarko is strategically positioned in the Shenandoah basin, which has the potential to become one of the most prolific new areas in the deepwater Gulf of Mexico.”
Anadarko is operator of both Shenandoah wells with a 30% working interest. ConocoPhillips has 30%, and Cobalt International Energy LP has 20%. Holding 10% each are Venari Resources LLC and Marathon Oil Corp.
ConocoPhillips noted that it had doubled its deepwater Gulf of Mexico acreage position in the last 2 years.
Anadarko has a 15% working interest in both the Coronado well more than two blocks southeast on Walker Ridge 98 and the Yucatan prospect on Walker Ridge 95 about 3 miles south of Shenandoah-2.