BP Exploration will spend $200 million this year on a fast track appraisal of its Cusiana oil and gas discovery in Colombia.
The decision to channel more funds into Colombia follows encouraging initial results from BP's 1 Buenos Aires well, 3.1 miles south of 2A Cusiana, which established Cusiana as a significant discovery (OGJ, July 15, 1991, p. 47).
BP's 1 Buenos Aires, drilled to 16,000 ft, cut a gross hydrocarbon column of 881 ft in three successive zones: Eocene Mirador and Paleocene Los Cuervos and Barco.
BP called the results "very encouraging." It has begun tests to confirm flow rates and the likely mix of oil, condensate, and gas in the reservoir.
Cusiana lies mainly in the 378 sq km Santiago de las Atalayas license in the Llanos foothills, about 100 miles northeast of Bogota. The 1 Buenos Aires is in the adjoining 157 sq km Tauramena license.
RESERVES
John Browne, BP Exploration chief executive officer, said the planned appraisal program is a very considerable undertaking that in 1992 will yield a reliable estimate of Cusiana reserves. The company will not declare any of the reserves proved for 1991.
Some industry sources say Cusiana could hold reserves of 2 billion bbl of liquids, along with a significant volume of gas.
In its 1991 annual report, Cusiana interest owner Triton Energy Corp., Dallas, said independent consultants DeGolyer & MacNaughton reported initial proved reserves for the company's interests in the 1 Cusiana and 2A Cusiana wells. Based on results from the two wells, Triton's share of proved reserves as of May 31, 1991, were 14 million bbl of liquids and 84 bcf of natural gas. D&M reported gross proved undeveloped reserves associated with Triton's reported net proved undeveloped reserves for four sands encountered in the two wells at 87 million bbl of liquids and 526 bcf of gas, according to Triton's annual report.
BP estimated the fields may cover an areal extent of as much as 50,000 acres, Triton said.
"The operator expects the individual wells to produce between 10,000 and 15,000 b/d of oil and initial field production to commence in 1993 at 60,000 b/d utilizing an existing pipeline near the field," Triton said. "Consideration is being given to building a larger pipeline to handle any higher volumes as the field is developed."
BUILDUP
Embarking on the Cusiana appraisal program will require a substantial buildup in the company's Colombian operation. By yearend BP's Colombian workforce will increase to 500 from the current 120, and the number of rigs under contract will increase to 10.
Most of the rig time will be spent on the Cusiana appraisal program, but a number of rigs will drill wildcats on other 100% owned BP acreage on the same geological trend to the north.
Triton said eight or nine additional appraisal wells are scheduled to be drilled in fiscal 1992-93.
BP holds 100% interests in the Pauto, Tamara, and Sacama license areas covering about 2,900 sq km. The first well on the Tamara license, 1 Tamara, is drilling below 16,000 ft.
BP also has taken a farmout on the 1,781 sq km Recetor license held by Maxus Energy Corp. After running seismic surveys, BP has the option to drill a well to increase its interest to 50% from an initial 1017, and take over as operator.
Cusiana is the most significant discovery made under BP Exploration's new policy of pursuing frontier prospects in a bid to replace the company's two biggest mature oil fields: Forties in the North Sea and Prudhoe Bay in Alaska.
BP holds a 40% interest in Cusiana. Its partners are Total Exploratie Mij. BV 40% and Triton Colombia Inc. 20%.
State owned Ecopetrol has a right to take a 50% interest in the discovery in the event of commercial development.
Copyright 1992 Oil & Gas Journal. All Rights Reserved.
