The Tonel-1 well is the first in the three well Ophir Energy-operated 2012 Block R drilling campaign in Equatorial Guinea, Africa, which encountered a 182 m (597 ft) gas-bearing column. The column had a total 117 m (383 ft) of net pay in mid-Miocene aged sands, trapped within a thrust belt anticline.
The well was drilled using the Eirik Raude semisubmersible rig. The well was spud in a water depth of 1,599 m (5,246 ft) and was drilled to a total depth of 3,072 m (10,078 ft) subsea.
Gross in-place mean resources for the Tonel-1 discovery are estimated at 1.1 trillion cu ft of gas. Gross recoverable mean resources are estimated of 800 billion cu ft (Bcf) of gas.
The Erik Raude rig will now move to undertake appraisal and satellite exploration drilling around Ophir's previous Fortuna-1 gas discovery.
Nick Cooper, CEO of Ophir said, "The drilling program will now return to the vicinity of our earlier Fortuna-1 discovery. The Fortuna East-1 and Fortuna West-1 wells are designed to appraise 603 Bcf of the Fortuna Fan discovery and also to target additional cumulative exploration volumes of 833 Bcf. The three-well campaign is due to complete by September."

