Exxon Exploration Co. and BP Exploration Inc. are weighing development options for a Gulf of Mexico oil and gas discovery in more than 4,650 ft of water.
Partners began studying development concepts for their Diana discovery after the third well drilled on the prospect confirmed a gross hydrocarbon column of more than 1,400 ft.
The Diana prospect covers parts of East Breaks Blocks 945, 946, 988, and 989 in the western gulf, about 120 miles south of Freeport, Tex. Operator Exxon holds 66.7% interest in Diana and BP 33.3%.
The Ocean Valiant semisubmersible rig conducted a drillstem test at the third Diana well in 4,657 ft of water, a Gulf of Mexico water depth record for production testing. The well, the first Diana appraisal on Block 946 after the discovery well and one appraisal on Block 945, flowed as much as 4,838 b/d of oil and 2.6 MMcfd of gas through a 13/16 in. choke from an 84 ft interval at an undisclosed depth.
Log analyses and wireline tests in fourth quarter 1991 confirmed the Diana discovery well on Block 945 found oil and gas at 10,200-600 ft. Exxon and BP drilled 1 East Breaks 945 wildcat to 11,930 ft.
Based on test results, Exxon estimates Diana's hydrocarbon reserves in place at about 350 million bbl of oil equivalent.
Exxon this year in the gulf claimed the world water depth record for mooring a semisubmersible drilling rig when it drilled its Rockefeller wildcat with the Ocean Valiant in 4,864 ft of water on East Breaks Block 992.
Exxon deepwater acreage
Diana is one of seven Gulf of Mexico discoveries in more than 1,350 ft of water either producing or advancing toward development in which Exxon has interest.
Among the other deepwater discoveries are:
- Zinc, a four tract unit Exxon operates with a 100% interest about 45 miles south of Grand Isle, La. Three wells in about 1,500 ft of water produce through a subsea template on Mississippi Canyon Block 354 tied back to the Alabaster platform in about 470 ft of water on Mississippi Canyon Block 397.
- Ram-Powell unit, a Shell operated project in 3,250 ft of water on Viosca Knoll Blocks 867, 868, 911, 912, 913, 955, 956, and 957. Exxon holds a 31% interest.
- Vancouver unit, a Chevron operated project on Green Canyon Blocks 161, 205, and the east half of 160. Exxon holds a 38% interest.
- Ursa unit, a Shell operated project under appraisal on Mississippi Canyon Blocks 808, 809, 810, 852, and 853. Exxon holds a 16% interest.
- Brutus unit, a Shell operated project in about 3,000 ft of water on Green Canyon Blocks 158 and 202. Exxon acquired an interest.
- Mickey prospect, the gulf's first intentional subsalt discovery in about 4,350 ft of water on Mississippi Canyon Block 211. Operator Exxon and BP each hold a 50% interest.
Exxon estimates its combined net recoverable reserves from those deepwater developments at more than 500 million bbl of oil equivalent. In all, Exxon holds interests in 150 deepwater tracts covering nearly 640,000 net acres in the gulf.
Exxon offered solo apparent high bids on 32 central gulf deepwater blocks at Minerals Management Service's offshore lease Sale 157 last month in New Orleans. The sale drew bids on 442 tracts in more than 400 m of water (OGJ, May 6, p. 40).
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