Onshore exploration enters Ghana after 40-year hiatus

Dec. 1, 2015
EPI Group’s Ghanian joint venture company EPI SonarTusk has signed a 2-year contract to support seismic exploration by Ghana National Petroleum Corp. in the Voltaian basin. The operator will acquire 2D seismic in the 104,000-sq-km basin, which covers about 40% of Ghana’s land mass.

EPI Group’s Ghanian joint venture company EPI SonarTusk has signed a 2-year contract to support seismic exploration by Ghana National Petroleum Corp. in the Voltaian basin. The operator will acquire 2D seismic in the 104,000-sq-km basin, which covers about 40% of Ghana’s land mass.

The Voltaian basin consists of sedimentary Neoproterozoic rocks with similarities to hydrocarbon producing areas in other parts of North Africa. Exploration in such a basin carries higher risk than most conventional plays due to age and probable geological history of the subsurface, the company said. Volta Lake, the world’s largest man-made water body, also adds to the complexity of shooting seismic in the basin.

Ghana’s exploration efforts shifted offshore in the mid-1970s with the discovery of South Tano field in 1978, by Phillips Petroleum. In late 2015, Erin Energy Corp. reported that Ghana’s 373,000-acre Expanded Shallow Water Tano (ESWT) block holds 500 million bbl of oil and 282 bcf of natural gas in place (OGJ Online, Oct. 6, 2015).

The EWST block is north of giant Jubilee oil and gas field, which is operated by Tullow Oil PLC (OGJ Online, Aug. 17, 2015).

Alexander Kofi-Mensah Mould, acting chief executive of GNPC, said the operator wants to better understand the basin and its potential for development before inviting partners to join, given the associated risks of Ghana’s onshore potential.