Ann: Drilling Activity Update , page-11

Extract from Tullow's trading statement dated 27/01/11:

Mauritania

The Cormoran-1 exploration well (Tullow 16.2%) located offshore Block 7 completed drilling in January 2011. The objective of the well was to appraise the Pelican gas discovery and to target two underlying exploration prospects; Cormoran and Petronia. The well successfully intersected gas in both Pelican and Cormoran. The Pelican interval was flow tested at a stabilised flow rate of approximately 23 mmscfd. In the deeper Petronia target, the well encountered rich gas in Turonian-age reservoirs. However drilling had to be stopped for operational reasons before fully penetrating the trap. The Maersk Deliverer rig has now moved to Block 6 where it has commenced drilling the Gharabi prospect (Tullow 22.4%).

Gross production from the Chinguetti field (Tullow 19.01%) in Q4 2010 averaged just over 7,400 bopd


Planned 2011 Exploration Programme

Block Prospect Interest Spud Date
Block 6 Gharabi 22.4% In progress
Block 6 Sidewinder 22.4% 2H 2011

Regards

SP