Production Test Update: China

Roc Oil Company Limited 13 June 2006 13 June 2006 ROC OIL COMPANY LIMITED ('ROC') STOCK EXCHANGE RELEASE PRODUCTION TESTING UPDATE: WEI-6-12S-1, OIL DISCOVERY, OFFSHORE CHINA KEY POINTS • Production testing of each of three separate hydrocarbon columns encountered by the Wei-6-12S-1 oil discovery offshore China, has resulted in oil flows from all test zones and a total collective stabilised rate of up to 5,750 barrels of oil per day ('BOPD'). • The next step in appraising the commercial potential of the field will be drilling the first side-track well, Wei 6-12S-1Sa, which is designed to locate and core the relevant reservoir intervals. This will commence later this week. 1. OPERATIONS Since the last Stock Exchange Release on 24 May 2006 regarding the Wei-6-12S-1 exploration well in Block 22/12, Beibu Gulf, offshore China, three separate production tests have been conducted successfully. As at 0600 hours (local time) 13 June 2006, the current operation was preparing to drill a sidetrack hole, primarily to obtain core data from the oil reservoirs. 2. PRODUCTION TEST RESULTS As stated in previous Stock Exchange Releases, the Wei-6-12S-1 production testing programme was designed to provide the Joint Venture with the maximum amount of technical data for possible field development rather than maximum flow rates. 2.1 Lower Sand Package The first test had three main aims: to confirm the hydrocarbon type in the 111 metres gross column (35 metres net pay); to determine if a hydrocarbon-water contact is present; and to provide productivity data. The test perforated 12 metres between 2,435.5 metres below rotary table ('mBRT') and 2,447.7 mBRT and flowed 35 degree API oil through various choke sizes, up to a 32/64 inch choke, at stabilised rates up to 1,725 BOPD. The test conclusively proved that the hydrocarbon type present is oil. The test did not produce any water, despite being located near the possible oil-water contact, which strongly indicates that oil-water contact is not present in the well. Preliminary pressure analysis confirms this and suggests that the oil-water contact may be more than 20 metres down dip from the base of the oil column seen in the well. 2.2 Middle Sand Package The purpose of the second test was to obtain productivity data from the 65 metres gross oil column (31 metres net pay) encountered. Specifically the test perforated a total of 28 metres over two zones, 2,228.5 mBRT to 2,241.5 mBRT and 2,201.0 mBRT to 2,216.0 mBRT. The test flowed 39 API oil, through various choke sizes up to 48/64 inch, at stabilised rates up to 2,575 BOPD with no associated water production. The test results indicate that the reservoir has good natural productivity. 2.3 Upper Sand Package The third test aimed to provide productivity data from the 71 metres gross oil column (14.5 metres net pay) in the upper sand package and to obtain further insight as to how far down dip the oil bearing reservoir may extend. This test perforated 16 metres between 2,054 mBRT and 2,070 mBRT and flowed 38 API oil, through various choke sizes up to 44/64 inch, at stabilised rates up to 1,450 BOPD. The test results indicate a reasonably productive reservoir. Pressure gradient information suggests that the oil column extends down structure from the discovery well. 3. NEXT PHASE OF APPRAISAL PROGRAMME The next phase of appraisal will be the drilling of a sidetrack hole close to the original discovery well in an attempt to further delineate and core the relevant reservoirs. The Wei 6-12S-1Sa sidetrack is expected to commence drilling later this week. Due to the proximity of the sidetrack to the discovery well, the Joint Venture does not expect to make any further Stock Exchange announcements about the progress of drilling until this first sidetrack is completed in late June. It is anticipated that a second sidetrack well will be drilled after the first sidetrack is completed. This second sidetrack will be designed to intersect the various reservoir sands in a down dip position relative to the discovery well, including the possible downdip development of a small sand section intersected in the lower part of the upper sand package in the discovery well. This sand section was not production tested in the discovery well but oil was recovered during wireline sampling. Another important phase of appraising the Wei South discovery is the integration of well and seismic data to determine whether or not the various hydrocarbon sands have recognisable seismic signatures. Initial results of this work are encouraging. 4. CEO COMMENT Commenting on the production test results of the well, ROC's Chief Executive Officer, Dr John Doran stated that: 'The Joint Venture is maintaining its methodical approach to appraising the commercial potential of the Wei South discovery and on the basis of the recent production test results it would seem to be a case of - so far so good.' 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 up to a 51% funding equity level in any commercial development within Block 22/12. ** A subsidiary of First Australian Resources In accordance with new Alternative Investment Market of the London Stock Exchange ('AIM') rules the information in this report has been reviewed by an appropriately qualified person with more than 5 years relevant industry experience, specifically, Dr John Doran, Bsc (Hons) Geology; M.Sc; PhD, Chief Executive Officer, Roc Oil Company Limited, and a member of the Society of Petroleum Engineers. 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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