Rockpool Acqui Regulatory News (ROC)

23 Apr 2007 07:02

Roc Oil Company Limited23 April 2007 23 April 2007 ROC OIL COMPANY LIMITED ("ROC") STOCK EXCHANGE RELEASE Drilling Activity Update: Offshore Perth Basin Exploration Drilling - Frankland-1 KEY POINT • The Frankland-1 exploration well, in WA-286-P in the offshore Perth Basin, is being plugged and abandoned as a gas discovery. The discovery needs to be evaluated in more detail to determine its size and whether or not an associated oil log is present. Preliminary indications suggest that the structure could contain between 60 and 90 billion cubic feet of gas in-place and that if an oil leg exists it is likely to be small. Roc Oil (WA) Pty Limited advises that, as of 0600 hrs on 23 April 2007Australian Western Standard Time ("AWST"), the Frankland-1 well was beingplugged and abandoned as a gas discovery. Since the last Drilling Report on 17April, 2007, the well drilled to a Total Depth of 2,340 metres Below RotaryTable ("mBRT") and an extensive evaluation programme was carried out. Preliminary interpretation of wireline and pressure data suggests that the wellintersected 35 metres of gas saturated sand of which approximately 28 metresappear to be net pay of moderate to good quality. The gas sand is at the top ofthe objective section at 1,986 mBRT and is interpreted as being equivalent tothe Dongara Sandstone. Underlying the gas sand there are 232 meters of shalesinterbedded with generally tight sands with gas indications down toapproximately 2,065 mBRT. Below this shale-sand sequence there are severalwater-bearing sands near Total Depth. An obvious gas-water contact was not seenin the well and further evaluation is required to determine how much of thestructure, which has a vertical relief of more than 100 m, is gas filled.Initial calculations for the 35 metre gas sand suggest in-place gas could rangebetween 60 and 90 billion cubic feet. On balance the well data suggest that ifan oil leg is present it is likely to be small. The forward programme for the "Premier Wilcraft" rig is to move to thePerserverance-1 exploration well location in WA-325-P, approximately 80 km northof Frankland-1, where drilling is expected to start prior to the end of theweek. 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% In accordance with ASX Listing Rules and AIM Rules, the information in thisRelease has been reviewed and signed off by Dr John Doran, Chief ExecutiveOfficer, Roc Oil Company Limited, BSc (Hons) Geology; MSc and PhD. Dr Doran hasat least five years' relevant experience within the sector and consents to theinformation in the form and context in which it appears. Damian FisherGeneral ManagerExternal Affairs & Investor Relations For further information please contact: Dr John Doran on Tel: +61-2-8356-2000 Fax: +61-2-9380-2635 Email: jdoran@rocoil.com.au Or visit ROC's website: www.rocoil.com.au Dr Kevin Hird General Manager Business Development Tel: +44 (0)207 586 7935 Fax: +44 (0)207 722 3919 Email: khird@rocoil.com.au Nick Lambert Bell Pottinger Corporate & Financial Tel: +44 (0)207 861 3232 This information is provided by RNS The company news service from the London Stock Exchange