Exploration Update: China

Roc Oil Company Limited 08 May 2006 8 May 2006 ROC OIL COMPANY LIMITED ('ROC') STOCK EXCHANGE RELEASE EXPLORATION DRILLING UPDATE: WEI-6-12S-1 WELL, OFFSHORE CHINA Wei-6-12S-1, Block 22/12, Beibu Gulf, Offshore China (ROC: 40% & Operator) As at 0600 hours (local time) on 8 May 2006, the Wei-6-12S-1 exploration well had drilled to Total Depth of 2,535 metres below rotary table ('mBRT') and the current operation was preparing to run wireline logs. Since the last Stock Exchange release, on 5 May 2006, when the well's reported depth was 2,007 mBRT, a gross sand-shale-silt interval, approximately 528 metres thick, has been drilled and a number of sandstones with oil and wet gas shows encountered. Until electric logs have been acquired and analysed, it is not possible to comment as to the commercial significance of the hydrocarbon shows seen in the well. Subject to hole conditions, initial log results are expected to be available within the next few days and a Stock Exchange release will be made as soon as possible thereafter. The Wei-6-12S prospect represents an unusual structural target. Within a small (about one sq km) area of closure, which has about 90 m of vertical closure, lies a thick (hundreds of metres) gross prospective sedimentary sequence which creates a potential structural trap capacity in the order of a few to many tens of millions of barrels of oil. Information from wells within and adjacent to Block 22/12 suggests that: reservoir quality will be good to excellent; the hydrocarbon type is likely to be oil rather than gas; recovery factors should be high; and oil viscosity is unlikely to be a problem in the targeted reservoir section. Wei-6-12S-1 is positioned so as to test the structure some 20 to 30 metres below its crest. The well is in about 30 metres of water, approximately 3 km southwest of the 2002 Wei-6-12-1 oil discovery. The Block 22/12 Joint Venture comprises*: Roc Oil (China) Company 40% and Operator Horizon Oil Limited 30% Petsec Energy Ltd 25% Oil Australia Pty Ltd** 5% *The China National Offshore Oil Company ('CNOOC') is entitled to participate at a 51% funding equity level in any commercial development within Block 22/12. ** A subsidiary of First Australian Resources Michelle Manook For further information please contact: General Manager - Corporate Affairs 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
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