Norwegian geoscience data services firm TGS has reached agreement with Angolan state oil firm Sonangol to begin a 3D multi-client survey covering nearly 4,825 square miles (12,500 square kilometers) offshore Angola.

The survey will begin over blocks 36 and 37 in late January before continuing over block 35, with completion expected during the third quarter of this year. The firm said that the blocks are highly-prospective deep water pre-salt blocks awarded by Sonangol to exploration and production companies in late December 2011.

TGS said that the high-potential pre-salt hydrocarbon play off the coast of Angola lies between 6,560 and 16,400 feet (2,000 and 5,000 meters) below sea level. Angola is already Africa's second-largest oil producer and the conjugate margin pre-salt basins, which are believed to be similar to hydrocarbon rich basins offshore Brazil, open a new frontier in petroleum exploration, the firm added.

"We look forward to our new, long-term relationship with Sonangol to support oil and gas exploration in the Republic of Angola," said Rod Starr, TGS's senior vice president for Africa, Middle East and Asia Pacific. "Entry into this market is consistent with our plans for strategic growth. TGS's commitment to expanding multi-client data in the offshore areas of West Africa has extended over 10 years and we are excited to have the opportunity to now add 3D data in offshore Angola to the TGS data library."

TGS, which has chartered vessel capacity for the project, will process the 3D seismic data in both time and depth using its proven sub-salt capability developed in similar basins. Preliminary products will be available to participating companies in the fourth quarter of this year with a final processed product expected by 4Q 2013.

Tags: TGS-NOPEC Geophysical Company