Tullow Oil Updates Drilling Activities

Tullow Oil provides an update on recent drilling activities in Mauritania and Angola.

MAURITANIA BLOCK 1 - Faucon-1 Exploration Well (Tullow 20%)

Drilling on the Faucon-1 exploration well in Block 1 offshore Mauritania has now been completed. The well reached a total depth of 4,170m and encountered a total of 96.5m of potential reservoir of which the upper 14m is hydrocarbon bearing. The hydrocarbon fluid composition will not be finally determined until the downhole pressurised fluid samples recovered from the well have been fully analysed in an onshore laboratory in January 2006. The well will now be plugged and abandoned.

ANGOLA BLOCK 10 - Ngueve-1 and Henda-1 Exploration Wells (Tullow 15%)

The two well exploration program in Block 10 offshore Angola has now concluded with both wells being plugged and abandoned.

The Ngueve-1 well was spudded on November 3, 2005 and intersected all of the planned objectives before reaching a total depth of 2,830m. Wireline logs indicated that all the porous zones encountered by the borehole are water bearing and the well was plugged and abandoned on November 30, 2005.

The second well, Henda-1, commenced on December 5, 2005 and was drilled to a total depth of 1,539 meters. Although the main objective was intersected, no liquid hydrocarbons were encountered. The well was therefore plugged and abandoned on December 15, 2005.

Block 10 is a largely unexplored block covering some 4,800 sq km. Although the wells did not encounter commercial hydrocarbons, they provided key geological and geophysical information that will be integrated with the 3D seismic data to allow further evaluation of the prospectivity of Block 10 and the region.

Commenting today, Aidan Heavey, Chief Executive of Tullow said:
"Although we believe the Faucon well is most unlikely to lead to a commercial development, it significantly upgrades the prospectivity of Tullow's regional position in Mauritania and Senegal, where further work is planned for 2006. Similarly, while we are disappointed with the result of the Ngueve and Henda wells, we remain committed to developing a long-term business in Angola. "