Roc Oil Company Limited 20 December 2005 20 December 2005 ROC OIL COMPANY LIMITED ("ROC") STOCK EXCHANGE RELEASE DRILLING ACTIVITY UPDATE FAUCON-1 EXPLORATION WELL, OFFSHORE MAURITANIA ROC advises that since the Company's last "Drilling Activity Update" on 13 December, 2005, the "Stena Tay" drilling rig has drilled Faucon-1 a further 496 metres to a Total Depth of 4,170 metres without encountering any significant hydrocarbons. The current operation is preparing to plug and abandon the well as a regionally significant but sub-commercial, discovery. Therefore, the main outcome of the drilling of Faucon-1 remains as reported last week: it encountered two hydrocarbon-bearing sandstones some 150 metres apart. The upper sandstone is gas-bearing and four metres thick while the lower 40 metres thick sandstone has a 10 metre interval at the top of it which appears to contain light oil or liquids-rich gas-condensate. The composition of the hydrocarbon fluid cannot be finally determined until the downhole pressurised fluid samples recovered from the well have been fully analysed in an onshore laboratory. Faucon-1 is located in 1,162 metres of water, 140 km south of the Chinguetti Oil Field. Commenting on the Faucon-1 results, ROC's CEO John Doran said: "Any time you find net hydrocarbon pay in the Cretaceous in a previously undrilled area 140 km from Chinguetti, you have to be encouraged. Exploration offshore Mauritania is still in its infancy: more than 14 million acres/50,000 sq km; barely scratched by the drill bit." The Joint Venture Interests in Block 1 are: +----------------------------------------+------------+ | | Equity | +----------------------------------------+------------+ |Dana Petroleum (E&P) Limited (Operator) |36.0% | +----------------------------------------+------------+ |Gaz de France UK B.V. |24.0%* | +----------------------------------------+------------+ |Tullow Oil |20.0% | +----------------------------------------+------------+ |Hardman Petroleum (Mauritania) Pty |18.0% | |Limited | | +----------------------------------------+------------+ |Roc Oil (Mauritania) Company |2.0% | +----------------------------------------+------------+ * Subject to farmin from Dana 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