Origin Energy, on behalf of the L11 Joint Venture, has advised that the exploration well Redback South-1, which was completed in October, began a well testing program on 17 November 2009. The well was perforated in the Wagina Sandstone from 3,882.5mD to 3,888.5mD (6 metres).
The Redback South-1 well will be flare tested over a 3-4 day period and then shut-in for a 7 day pressure buildup. This information is expected to give an indication of the potential size and commercial significance of the discovery. Initial gas rates of up to 38.4 mmscf/day have been recorded on a 1" choke, at a flowing wellhead pressure of 1,750 psi. Further information will be released when the test is completed.
Commenting on the initial test result, Origin's Executive General Manager, Geoscience & Exploration New Ventures, Dr Rob Willink, said, We are encouraged by the extraordinary gas flow rate achieved to date. Whilst this result indicates the excellent reservoir quality of the upper Wagina Sandstone, gas flow rate on its own is not a measure of the size of this new gas discovery. An indication of the commercial significance of this resource must await the analysis of pressure data collected over the duration of the test period.
Well type and location: Gas exploration well, Redback South prospect, onshore northern Perth Basin, Western Australia (L11). Redback South-1 was drilled in September 2009 as a directional well to intersect the reservoir interval approximately 570 metres SSE of the Redback-1 surface location. The structural compartment being targeted by this well on the downthrown side of a fault immediately south of the Redback-1 well, with closure independent of the Redback-1 structure.
The Redback South-1 reached a total depth of 3,934mD on 17 September after intersecting the Wagina reservoir objective depth at 3,882.5mD. Wireline logs and pressure data indicated the presence of gas in the uppermost Wagina Sandstone. Gas samples recovered indicated a gas composition similar to Beharra Springs. The well was cased and suspended and the rig released on 27 September 2009.
The surface location is Latitude: 29o 27 28.05 S;
Longitude: 115o 09 43.51 E
The initial interests are: Origin Energy Developments Pty Ltd * 67% and Australian Worldwide Exploration Ltd (AWE) 33%.