Tullow assessing potential in frontier basins offshore South America

Feb. 8, 2017
A 2,500-sq km (965-sq mi) 3D seismic survey is under way over block 15 in the Pelotas basin offshore Uruguay.

Offshore staff

LONDON– A 2,500-sq km (965-sq mi) 3D seismic survey is under way over block 15 in the Pelotas basin offshore Uruguay.

OperatorTullow Oil says the aim is to capture data over high-quality leads identified in the concession.

Elsewhere in South America, the company plans to acquire 3D seismic overGuyana’s offshore Orinduik license, awarded last year, and over the Kanuku license, both up-dip of ExxonMobil’s deepwater Liza oil discovery.

These programs should collectively cover up to 6,000 sq km (2,317 sq mi) and will assist evaluation of leads mapped on existing 2D seismic.

Off neighboring Suriname, the company is in a license containing the potentially high-impact Araku prospect, which the partners are looking to drill during the second half of 2017.

Araku is a large structural trap with a resource potential of more than 500 MMbbl, which has been de-risked by a 3D seismic survey shot in 2015 that identified geophysical characteristics consistent with potential oil or gas effects in the target reservoirs.

The partners are scouting for a rig for the well, which will likely cost Tullow $14 million net to drill.

Offshore Jamaica, following the completion of a drop core and seep study in the Walton Morant blocks that identified a live oil seep, the company will acquire a further 680 km (422 mi) of 2D seismic data before determining whether to follow up with a 3D survey.

Across the Atlantic, the company expects approval from Ghana’s government in mid-year for itsGreater Jubilee full field development plan.

This was submitted in December 2015, and has been redesigned in light of the current oil price environment to reduce the overall capital costs and allow flexibility on the timing of capital investment.

At the company’s nearbyTEN fields, gas compression/injection and water injection systems on the FPSO have been commissioned and are operational. In early January, the FPSO’s capacity was successfully tested at an average rate that exceeded the design capacity of 80,000 b/d during a 24-hr flow test.

Production testing and initial results from the 11 wells drilled to date indicate that reserves estimates for Ntomme and Enyenra are as anticipated.

However, there have been issues with managing pressures in the Enyenra reservoir, and no new wells can be drilled until after the ITLOS ruling on Côte d’Ivoire’s offshore median line dispute with Ghana which includes the TEN area.

Oral hearings are scheduled for this month, with a final ruling likely in 4Q. Drilling should then be ready to resume in 2018.

Gas production from the TEN fields is currently being re-injected. The gas export line between TEN and Jubilee is set to be connected this month with gas export due to start later this year.