Origin Energy, on behalf of the T/18P Joint Venture, advised that the Trefoil 2 gas appraisal well commenced drilling at 08:00 hours EDT on Tuesday, October 6, 2009. The well is being drilled using the semisubmersible drilling rig Kan Tan IV.

Trefoil 2 is located in exploration permit T/18P, operated by Origin some 38km west of the Yolla gas field and will appraise the Trefoil gas field discovered by Trefoil 1 in 2004.

Planned total depth of the well is 3,221mRT. The well is expected to reach the top objective in approximately 23 days. The primary objectives are the gas-bearing sands intersected in Trefoil 1 within the Paleocene and Cretaceous Eastern View Coal Measures. The well will be plugged and abandoned after the evaluation program is completed.

T/18P Participating Interests:

Origin Energy Resources Ltd* 39.0% (Operator) Australian Worldwide Exploration Limited 47.5% CalEnergy Gas (Australia) Ltd 8.5% Innamincka Petroleum Ltd 5%

Tags: Origin Energy