Norwegian oil firm Statoil, in collaboration with its project partner ExxonMobil, has made a large gas discovery off the coast of Tanzania.

The Ocean Rig Poseidon vessel drilled the Zafarani exploration well, located in Block 2 licence, to discover a proven 5Tcf gas column.

This is the fifth high impact discovery made by Statoil in the last 12 months; further wells will be drilled to an expected total depth of 5,100m, at 2,582m underwater.

Statoil said that the well encountered 120m of excellent quality reservoir, with high porosity and high permeability. The gas-water contact has not been established and drilling operations are on-going, the company added.

Statoil executive vice president for exploration Tim Dodson said it was the company’s first operated discovery in East Africa.

"It is a demonstration of how Statoil’s exploration strategy of early access and high impact opportunities strongly supports the company’s ambition for international growth," said Dodson.

Tanzania Petroleum Development Corporation (TPDC) managing director Yona Killaghane said added that the discovery could be a potential catalyst for large scale natural gas developments in Tanzania.

Earlier this week, the partnership signed an addendum to the production sharing agreement for Block 2. It stipulates the commercial terms in case of a development of natural gas resources in the block with the Tanzanian authorities.

Other discoveries by Statoil include Skrugard and Havis in the Barents Sea, Johan Sverdrup (former Aldous/Avaldsnes) in the North Sea and Peregrino South in Brazil.

Statoil operates the Block 2 licence on behalf of TDPC with an ownership share of 65%; its license partners ExxonMobil Exploration and Production Tanzania hold the remaining 35% stake.


Image: The Ocean Rig Poseidon encountered a proven 5Tcf gas column at the Zafarani location. Photo: courtesy of Statoil.