Large Basin Margin Fans and Structural Closures Identified

Rockhopper Exploration says an initial interpretation of the 3D seismic data collected over its licenses PL032 and PL033 in the Falkland Islands has revealed large fans and structural closures which could form targets for the next round of drilling. The largest fans cover approximately 40sq km and are located near to the Shell well, which recovered live oil.

CGGVeritas collected the 3D data between November 2006 and January 2007 over licenses PL032 and PL033, which were formerly held by Shell. Two wells were drilled by Shell on this acreage during 1998. Live oil was recovered from one, while oil and gas shows were found in the other. The collection of 3D over the sites of the wells allows Rockhopper to significantly reduce exploration risk.

The new Rockhopper 3D survey covers an area of 850 square kilometer and shows a number of large targets, which could be drilled during the next phase. Amplitude mapping indicates the presence of prominent fan-shaped anomalies along the eastern basin margin at the level of the main Post-rift source rock sequence. Two of these anomalies appear to coalesce and extend across a combined area of approximately 40 sq. km (which for the purposes of comparison, is slightly smaller by area than the Buzzard field in the North Sea). Neither fan anomaly has been tested by the two existing wells. These fans represent one of the largest prospects by area so far identified in the Rockhopper portfolio. The fans are located near to the Shell well, which recovered live oil to the surface and are in an area of the basin known to be generating oil. While oil shows were encountered in the center of the basin in the previous Shell wells, the eastern margin of the basin remains completely untested.

In addition, a number of structural closures have been mapped along the eastern basin margin. The largest structural closure identified to date is some 20km in length from north to south, closing against the eastern basin margin. The presence of basin margin closures and the identification of fan-shaped anomalies were the main targets of the 3D campaign. Both have now been successfully identified.

Mapping of the new 3D seismic will continue and additional technical work, which includes Amplitude versus Offset studies, basin modeling, reservoir modeling and a comprehensive study of the well logs and integration with the new 3D is also in progress.

The end of 2007 should complete all of the technical work on licenses PL032 and PL033, including a full prospect inventory, and a further announcement will be made at that time.

Pierre Jungels, Executive Chairman, commented:

We are very pleased to have identified encouraging indications of fan systems for the first time on our acreage. This target has the potential to be large and is in the area of the basin where oil has already been proven. In addition, the structural closures enhance the potential reserves of our prospect inventory. We will continue to refine our mapping before ranking our prospects and deciding on drilling targets.

We have already announced separately a positive EM result on Ernest and have other targets in Areas PL023 and PL024, giving a total potential figure of 2.5 Billion barrels recoverable in these additional license areas.

The market for semi – submersible rigs is easing and the market for farming out is improving and this gives us increased encouragement during the current phase of our technical work program.