Appraisal drilling key to West African E&D plans

April 27, 1998
West Africa Development Activity [164,339 bytes] Last year's string of giant oil discoveries off West Africa has led to an increase in exploration there and a scramble to secure acreage. This is the view of Wood Mackenzie Consultants Ltd., Edinburgh, which says 1997 was an outstanding year for the region's exploration and development companies. Deepwater areas off Angola and Congo Republic were said to be confirmed as a world-class exploration play, with production from the region
Last year's string of giant oil discoveries off West Africa has led to an increase in exploration there and a scramble to secure acreage.

This is the view of Wood Mackenzie Consultants Ltd., Edinburgh, which says 1997 was an outstanding year for the region's exploration and development companies.

Deepwater areas off Angola and Congo Republic were said to be confirmed as a world-class exploration play, with production from the region replaced almost six times by new finds and reserves upgrades.

"We predict," said Wood Mackenzie, "that 1998 will be another busy year in all sectors. New field developments will continue apace and production will continue to rise.

"Appraisal of some of the important recent discoveries will maintain high levels of exploration and appraisal drilling in 1998."

Exploration

The analyst said 70 exploration and appraisal wells, including 40 wildcats, were drilled last year in West Africa, excluding Nigeria, up from 53 in 1996 and 35 in 1995: "We expect drilling activity to maintain this high level in 1998."

Fourteen potentially commercial discoveries were made last year, said the analyst, adding combined reserves tentatively estimated at 2.86 billion bbl of oil.

Most significant were said to be Dalia, found by Elf Aquitaine SA on Block 17 off Angola, and Kuito and Landana found by Chevron Corp. on Block 14 off Cabinda.

Dalia has estimated reserves of 1.5 billion bbl of oil and is on the same block as Girassol, with estimated reserves of 700 million bbl. Both are expected to be developed with giant production barges.

Kuito has estimated reserves of more than 700 million bbl of oil, while Landana has an estimated 500 million bbl. Kuito is also likely to be developed with a floater, while Landana has yet to be appraised.

These three finds were said to account for 94% of new reserves found last year: "35% of the 40 wildcats drilled in 1997 were commercial discoveries. The average reserves found per wildcat were 71.5 million bbl, almost double the previous year, which was itself outstanding."

Eighteen new exploration licenses were awarded last year, down from 21 in 1996 but significantly higher than the five and 10 awarded in 1994 and 1995, respectively.

"The slight downturn in licensing activity," said Wood Mackenzie, "reflects reduced acreage availability as many companies chose to renew rather than relinquish.

"In 1998 several awards in Angola are pending, and many other exploration licenses are expected during the year in Cameroon, Equatorial Guinea, and Gabon."

West Africa's total discovered commercial reserves, excluding Nigeria, are said to amount to 17.3 billion bbl of oil, of which 9.6 billion bbl has not been produced.

"Total reserve replacement in 1997, comprising discoveries plus reserves upgrades, of 3.161 billion bbl of oil compares very favorably with the 544 million bbl produced last year."

Production

West Africa's production in 1997 averaged 1.49 million b/d, from fields in Angola, Cameroon, Congo, Equatorial Guinea, and Gabon. With Nigeria included, West African output averaged 3.85 million b/d.

"Output (excluding Nigeria) will continue to increase in the near term," said Wood Mackenzie," averaging about 1.58 million b/d in 1998 and reaching 1.83 million b/d in 2002."

The analyst expects 13 fields to be brought into production in West Africa this year (see table), while 12 fields were brought on stream in 1997.

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