US oil and gas explorer Anadarko Petroleum has discovered 30m of hydrocarbon pay at the Jupiter-1 discovery well, off the coast of Sierra Leone.

The Jupiter-1 well, located in block SL-07B-11, has been drilled to a total depth of 21,212ft, in water as deep as 7,215ft in the Sierra Leone/Liberia Basin.

Anadarko senior vice president Worldwide Exploration Bob Daniels said the well has been preserved for possible re-entry.

"We are planning potential drillstem testing in the basin, following the Mercury appraisal well, to provide additional information regarding reservoir quality and deliverability," he said.

The company will mobilise the rig to drill the Mercury-2 appraisal well in the same block once operations are complete at Jupiter.

Anadarko operates the block with a 55% interest, while other partners include Repsol Exploracion Sierra Leone and Tullow Sierra Leone B, which hold interests of 25% and 20% respectively.

The company also announced its latest appraisal well off the coast of Mozambique, Lagosta-3, which encountered about 176m of natural gas pay in multiple zones. Located 3km west of the Lagosta-1 discovery and 15km south of the Camarao-1 well, the Lagosta-3 appraisal well was drilled 13,715ft down, in water depths of 4,606ft.

Anadarko operates the 2.6 million acre Offshore Area 1 with a 36.5% interest, while other partners include Mitsui E&P Mozambique Area 1, which holds a 20% share, BPRL Ventures Mozambique with a 10% interest and Videocon Mozambique Rovuma 1, which also holds a 10% stake.