Vanco is preparing for a 3D seismic program to assess the sub-salt potential of Anton Marin

Following the strategic decision to exit the North Sea in favor of deepwater frontiers, Vanco selected the Lower Congo Basin offshore Gabon for its first foray into deepwater Africa. Production Sharing Contracts were signed in 1997 for the Anton Marin contract area and the adjacent Astrid Marin area. These blocks spanned water depths ranging from 1,000 to 3,000 meters in an area adjacent to the Congo/Angola region that was yielding giant field discoveries.

After acquiring 2D data to define prospect potential, Vanco attracted several industry heavyweights, including Total, Shell and others, to participate in the further exploration and development of both contract areas. The Vanco Gabon Group acquired a 4,000-square-kilometer 3D seismic survey over portions of the Anton and Astrid Marin permits, leading to the drilling of four wells in 2001. The wells were technically significant, confirming the presence and extent of the ancient Congo River sand channels, although source beds were found to lack communication to the reservoirs. In February 2003, the Vanco Gabon Group dissolved and relinquished the Astrid Marin contract area.

Vanco extended the 1.6-million-acre Anton Marin permit for six years as Operator with 100% participating interest, because only one of many potential play concepts had been evaluated. In 2005, Vanco completed the acquisition of a 2,261-kilometer 2D seismic program designed to further evaluate Anton Marin prospects and leads, particularly the numerous large structures associated with the Albian Madiela Formation ‘raft play’ which is a continuation of the Pinda play that has been found productive in Congo and Angola.

Recent discoveries in the deepwater basins of the Brazilian conjugate margin have generated active interest in the sub-salt potential of Anton Marin. Petrobras and partners discovered the sub-salt Tupi Field in the Santos Basin in 2,100 meters of water. The pay sand is 3,000 meters below a 2,000 meter salt layer and could contain as much as 8 billion barrels of recoverable oil. Since that discovery in October 2006, Petrobras has made other significant sub-salt finds in the Santos and Compos basins. On Anton Marin, a 3D seismic survey is planned for 2008 to identify attractive prospects for drilling.