BHP Billiton has a 75 per cent interest in the blocks and Mitsui Atlantic Energy BV holds a 15 per cent stake, state-owned PetroSA said in a statement.

PetroSA said the venture was in line with its current strategic objective of growing its exploration and production business by increasing oil and gas reserves in Africa.

Apart from the coast of South Africa, PetroSA has extended its interests to Gabon, Equatorial Guinea and Sudan.

"The Northern and Southern Blocks off the coast of Namibia are particularly exciting opportunities for PetroSA, which will be able to bring its technical capabilities...

in fields such as gas-to-liquids (GTL) technology to bear on this project," Sipho Mkhize, PetroSA's chief executive officer, said.

PetroSA operates the Mossel Bay plant, one of the world's largest gas-to-liquid (GTL) plant, second only to Sasol's Oryx 34 000 barrel-per-day GTL plant in Qatar.

The Southern and Northern Blocks are located in the northern part of Namibia's Orange Basin, adjacent to the Kudu gas field to the east, near the Ibhubesi gas field to the south-east.

Though the Orange Basin is considered an immature basin, these significant gas discoveries on the shelf area of the basin prove that a working petroleum system exists, PetroSA said.

The two blocks cover an area of 10 844 and 18 010 square km respectively, and water depths range from 200 to 3 000 metres.

PetroSA said it may exercise an exclusive option to obtain a further 25 per cent interest and lift its stakes in these blocks up to 35 per cent if encouraged by findings from a current evaluation being undertaken by BHP Billiton.

PetroSA already has another exploration venture in Namibian waters, also a 10 per cent interest in Block 1711.

Nampa-Reuters

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