Dunsborough-1, Offshore Perth Basin: ROC: 37.5% & Operator
Roc Oil (WA) Pty Limited, a wholly owned subsidiary of ROC, advises that the Dunsborough-1 exploration well, WA-286-P, in the offshore Perth Basin, has been classified as a new field oil and gas discovery.
Since ROC’s last Stock Exchange Report on 1 June 2007, Dunsborough-1 has been drilled to a Total Depth of 1,755 metres Below Rotary Table and a comprehensive wireline electrical logging and fluid pressure and sampling programme has been completed. Preliminary interpretation suggests that the well has intersected a minimum 25 metre gross hydrocarbon column of which approximately 18 metres is net pay. The accumulation appears to have a small (<13 metres) gross gas column above an oil column containing light oil (approximately 40o API) in sands of poor to moderate reservoir quality. Pressure data indicate that the total gross hydrocarbon column associated with the Dunsborough structure may be up to 70 metres. Tentative volumetric estimates by ROC suggest that the structure could contain between 20 and 40 million barrels of oil in‑place.
As of 0600 hours on 12 June 2007, Australian Western Standard Time ("AWST"), the current operation at Dunsborough-1 was preparing to plug and abandon the well in accordance with the pre-drill schedule.
Dunsborough-1, located approximately 25 km south of Geraldton, Western Australia and about 50 km northwest of the Cliff Head Oil Field, is the third and final well in an offshore Perth Basin drilling programme which was initiated in early April, 2007 by the WA-286-P and WA-325-P joint ventures, both of which are operated by ROC. The programme’s first well was the Frankland-1 gas discovery in WA-286-P, about 25 km southeast of Dunsborough-1, the programme’s second well was the Perserverance-1 gas discovery in WA-325-P, approximately 50 km to the northwest of Dunsborough.
Commenting on the three well programme ROC’s Chief Executive Officer, John Doran stated that:
"It is always nice to drill three offshore exploration wells and make three discoveries, particularly when that extends the known oil and gas fields some 200 kilometres along regional strike to the northwest of the Cliff Head Oil Field. However, at the end of the day we’re not looking to play with exploration success statistics but rather to clock up commercial success - and it will take some time to establish whether or not we have done that.
Of the three discoveries, Frankland and Dunsborough look as if they have the best chance of being developed, while Perserverance will probably need a lot of good things to happen around it if is going to make the grade.
Whatever the details, it would seem that an exploration programme that was regarded by ROC as the last throw of the dice in the northern offshore Perth Basin, has certainly provided enough success to cause us to move the discoveries on to the appraisal stage and continue to explore around and on trend from them."
Participating Interests in WA-286-P are:
Roc Oil (WA) Pty Ltd (Operator): 37.5%
AWE Oil (Western Australia) Pty Ltd: 27.5%
Wandoo Petroleum Pty Ltd (Mitsui & Co Group of Companies)*: 24.0%
ARC (Offshore PB) Limited: 6.0%
CIECO Exploration and Production (Australia) Pty Ltd: 5.0%
* Subject to a purchase agreement with ARC Energy
