Cairn Energy and its joint venture partners have completed operations on the SNE-1 well, offshore Senegal.
The well, which is about 100km offshore in the Sangomar Offshore block, was drilled to a total depth of 3,000m.
The discovery is forecast to be evaluated in 2015. SNE-1 is 1,100m deep, near the company's FAN-1 well, and could hold 150-670 million barrels of resources.
Cairn Energy discovered oil in the upper clastic target, but no hydrocarbons were found in the deeper target of karstified and fractured Lower Cretaceous shelf carbonates.
The company is the 40% owner of three blocks off Senegal, covering 7,490km². ConocoPhillips, FAR and the national oil company of Senegal, WI and Petrosen, own 35%, 15% and 10% stakes respectively.
Earlier this year, Cairn Energy and its partners discovered oil at the FAN-1 exploration well, about 60 miles offshore Senegal.
The FAN-1 well, in the Sangomar Deep block, was drilled to a depth of 16,164ft in about 4,700ft of water.
Cairn Energy is currently focusing on the Atlantic Margin, the Mediterranean and the UK and Norway.