Vanoil Energy Ltd. provided an update on the first quarter 2012 program. In 2011, Vanoil contracted Sproule International Ltd. ("Sproule") and Geoseis Inc. ("Geoseis") both of Calgary to interpret approximately 1,770 miles (2,850 kilometers) of seismic data. This data included, legacy 1,243 miles (2,000 kilometers), seismic data shot in 1975 by Chevron that has proved to be of immense value after reprocessing for structural analysis but lacking the offset range for amplitude analysis.
Vanoil acquired 850 line kilometers prospect grade seismic data in 2010 and 2011 at a cost of $8.5 million that has adequate offsets for the purpose of mining geological data from seismic amplitudes.
The data has been relative amplitude and Amplitude Versus Offset (AVO) processed by Statcom Ltd. of Calgary. Structural leads identified by Sproule and Geoseis are observed to be coincident with some of the AVO anomalies. This correlation has de-risked and ranked the Sproule identified 27 leads.
The complete seismic data has been further subjected to advanced reservoir characterisation techniques (Chimney analysis by dGB / Petro-explorers highly successful in North Sea, Gulf of Mexico and on shore basins in South America) ranking the 27 leads by their fault sealing and hydrocarbon charge attributes.
This has led to delineation of an area of approximately 656 square miles (1,700 square kilometers) on the South and South-West flanks of the South Anza basin. The area is analogues to Melut basin in Sudan and is characterised by 15 leads that are grouped into Eastern, Southern and Western lead areas.
The Eastern lead area bears strong characteristics to the Adar Yale oil field in Sudan. It composed of a string of 6 leads which start from the depo center of South Anza basin up along a rollover structures and ending on a Horst block of a Karoo Graben. Stratigraphic sequence analysis of seismic data and correlation near the Bahati and Endela wells, which 9 miles (15 kilometers) away from East focus leads and 12 miles (20 kilometers) for the Western focus leads respectively clearly correlates the likely source and possible reservoir facies. This is fundamentally different interpretative approach (AAPG approved) from past practices due to advent of seismic sequence and facies analysis techniques in the 80's. The structural considerations alone has been the criteria of choosing drilling sites in past failed exploration programs.
In order to properly place the over 29 square miles (75 square kilometers) 3D seismic survey (cost $3.5 million) on one or two of the 15 leads, a 48-mile (78-kilometer) 2D seismic survey at a cost of $800,000 has been designed and shot in Block 3B along a string of 6 leads identified approximately 9 miles (15 kilometers) from the Bahati well. It was initially targeted for shooting in the last quarter of 2011 but heavy rains and adverse HSSE issues led to its postponement.
The 2D and 3D seismic data to be acquired in the second and third quarter of 2012 will lead to more advanced reservoir characterization techniques being applied for the purpose of choosing an optimum drilling site.
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