Nexen has failed to prove up oil in a sub-salt deepwater well in the US Gulf of Mexico.

Nexen said its Kakuna sub-salt exploration well in Green Canyon block 504 in the US Gulf of Mexico is to be plugged and abandoned after drilling to a depth of 30,300 feet without encountering commercial hydrocarbons.

Well costs were put at Can $120 million (US $120.80 m) net to Nexen  but the company goes on to point out that it has already found over 500 million barrels of reserves – 115 m net to Nexen – in and around the Appomattox field are in the US Gulf.