Water Depth Marks For West Africa (13394 bytes)
Exploration drilling in deep water off West Africa is on the upswing.
Wood Mackenzie Consultants Ltd., Edinburgh, expects 1995 activity to account for 15 deepwater wells drilled in the region.
The analyst defines deep water as 200 m or more.
Wood Mackenzie said deep water off West Africa holds three commercial oil discoveries, of which Nkossa is the most significant. Although it was discovered in 1984, it just now is under development.
"With liquids reserves of 600 million bbl, we regard Nkossa as the real pointer to the great potential of the West African deepwater province," Wood Mackenzie said.
There are 17 current exploration licenses off West Africa in deep water, covering a total 91,500 sq km. Twenty-nine companies have interests there, with Occidental Petroleum Corp., Elf Aquitaine SA, Royal Dutch/Shell, and Exxon Corp., in that order, having the most exploration commitments.
The three commercial finds to date are Elf's Nkossa field off Congo, Mobil Corp.'s Zafiro off Equatorial Guinea, and Agip's Kitina Sud off Congo. Shell's Bengo strike off Angola is regarded as noncommercial.
By the end of 1995 a total of 34 wells will have been drilled off West Africa, Wood Mackenzie said, of which 28 were new field wildcats. Twenty-five of these have been drilled since early 1992.
Wood Mackenzie reckons this year's 15 well completions will be a short term peak, with 13 wells scheduled to be drilled next year.
Beyond 1996, activity will be governed by appraisal work and commitments on new blocks.
Three new licenses are expected to be awarded early in 1996.
Amoco Corp. is negotiating for Block 18 and Mobil for Block 20 off Angola, Wood Mackenzie reported. Off Equatorial Guinea, Atlantic Richfield Co. is pursuing two licenses, one of which will be in deep water.
"Future drilling levels will remain high in the near term as operators strive to fulfill work commitments on recently awarded licenses," Wood Mackenzie said. "In 1996, a minimum of 10 wildcats are expected, excluding nonobligatory exploration and appraisal wells, that may bring the total to 13. In 1997, at least eight obligation wildcats are expected, but nonobligation wells are more difficult to predict at this stage."
PRODUCTION OUTLOOK
Of discoveries to date, Wood Mackenzie expects Elf's Nkossa field to be the first on production. Start-up is due in April 1996.
Nkossa straddles water depths of 180 m to more than 350 m. Two fixed platforms have been installed in about 190 m of water.
Mobil's Zafiro field is a March 1995 discovery. Wood Mackenzie said reserves are estimated at 100 million bbl of oil, "...but there is thought to be considerable upside potential."
Agip's Kitina Sud field holds estimated reserves of 20 million bbl of oil. Kitina field in shallower water is estimated to have 90 million bbl oil reserves and is under development with first production expected in 1997.
Kitina Sud likely will be tied back to Kitina at a later stage, Wood Mackenzie said. On a stand-alone basis, Kitina Sud would be noncommercial.
The analyst said Shell's Bengo has difficulties that include thin sands, low production potential of the Bengo-1 well, and a shallow reservoir that hinders development by deviated drilling.
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