Project Profile
Value: Undisclosed
Location: Southern Bonaparte Basin, offshore Western Australia
Area: 5,420 km² or 1,339,310 acres in total
Start-up Year: -
The Octanex Group holds a 75% interest in WA-375-P and WA-376-P permits and the Operator of the Torrens Joint Venture is Goldsborough Energy Pty Ltd, a wholly-owned subsidiary of Octanex NL. The Torrens Joint Venture members are: Octanex Group (75%) and Torrens Oil & Gas Pty Ltd (subsidiary of Gascorp Australia Pty Ltd) (25%). The permits were granted by the Designated Authority on 6 February 2006, both for a period of six years. They comprise 65 graticular blocks (approximately 5,420 km² or 1,339,310 acres in total) located in the Southern Bonaparte Basin, offshore Western Australia. During year 3 of the permits, the Gold 2D seismic survey acquired some 1,875 line km of new data, of which 1,800 km was within the area of the WA-375-P and WA-376-P permits. That survey data has undergone a number of rounds of processing and has been interpreted. A ‘region-wide’ reprocessing project has been completed that incorporated in excess of 11,675 km of existing 2D data, including approximately 730 km of 2D data previously acquired within the area of WA-375-P and WA-376-P.
The area of main interest in the permits is in the vicinity of the Torrens-1 well, which encountered what are thought to be residual oil shows. Torrens-1 was drilled by Kufpec Australia Pty Ltd in 1993 and targeted fluvio-deltaic sandstones of the Keyling Formation within a three-way dip and fault dependent closure below the Hyland Bay Formation. Increasing closure was mapped with depth and the well was directionally drilled below the lower section of the Hyland Bay Formation to ensure all potential objectives would be intersected in a near crestal position. The well reached a total depth of 2497 MDRT within the Kuriyippi Formation. Two main zones of hydrocarbons were encountered; residual oil in sandstones of the Fossil Head Formation at 1517 – 1523.8 MDRT, and possible minor moveable oil and gas at low saturations in the Tern Member of the Hyland Bay Formation at 994 - 1000.5 MDRT. Analyses of oil inclusions in detrital grains provided evidence for the existence of three palaeo-oil columns at Torrens-1; a 42 metre thick column within the Permian Fossil Head Formation and two separate columns within the Late Carboniferous Kuriyippi Formation.
Work Program:
The permits are in year 6 of their initial terms where the work programme obligations in both cases are to continue geological studies and review the permit data obtained to date with a view to seeking renewals.
Operators:
Torrens Oil & Gas Pty Ltd (subsidiary of Gascorp Australia Pty Ltd): Operator with 25% interest
Octanex Group: 75% interest