Tullow mulls Guyana drilling campaign on heavy oil determination

Tullow Oil PLC and its Orinduick license partners are assessing the commercial viability of two offshore Guyana discoveries after lab results determined that the oil recovered is heavy crude with a high sulfur content.

Jethro-1 and Joe-1 proved two different oil plays in the basin in August and September (OGJ Online, Aug. 12, 2019; Sept. 16, 2019). The Jethro-1 well discovered 55 m of net pay in high-quality sandstone in the Lower Tertiary and Joe-1 encountered 16 m of net pay, opening a new play type in the Upper Tertiary. Both wells were drilled within budget, with measure while drilling logging tool and conventional wireline.

Tullow said it remains confident in the potential across multiple prospects in both the Cretaceous and Tertiary throughout the Orinduik and Kanuku blocks.

“While the results from the Jethro and Joe wells in the far north of our acreage continue to be evaluated, the petroleum system models are being updated in pursuit of additional prospects and lighter oil in the area and, together with the Carapa well result, these will inform the 2020 drilling campaign,” Tullow said in a Nov. 13 trading update.

“We remain confident in the broader light oil potential of the Orinduik and Kanuku blocks located in this prolific oil basin,” added Tullow Chief Executive Officer Paul McDade.

The Carapa well, targeting the Cretaceous play in shallow water on Repsol’s Kanuku license just south of Orinduik, is currently drilling. Started at the end of October, results are expected before yearend.

Orinduick block partner Eco (Atlantic) Oil & Gas Ltd. also is optimistic in considering development scenarios for the block.

Eco said the samples indicate mobile heavy crudes, not dissimilar to the commercial heavy crudes in the North Sea, Gulf of Mexico, Brazil’s Campos basin, Venezuela, and Angola, with high sulfur content.

Colin Kinley, Eco co‐founder and chief operating officer said, “The fact that the oil is already hot in the reservoir, and mobile, and has high-quality porous sand to travel through, helps to eliminate a great part of the conventional heavy oil challenge. Having 8,500 psi in the porous warm formation is an added advantage to drive the oil to the well. Horizontal well technology can allow excellent access to these thick fields and generally reduces the need for multiple additional wells, leading to lower development cost per barrel,” he said.

The partners have sought a third-party consultant with heavy oil development expertise to answer technical queries and provide an initial assessment of several potential development drilling and production scenarios.

While results are being evaluated, the company is in the planning stages of a 2020 drilling campaign in pursuit of additional discoveries. Drilling will be determined by the partners in the coming months.

Tullow Guyana BV operates Orinduick with 60%. Partners are Total E&P Guyana BV, 25%, and Eco, 15%.

Contact Mikaila Adams at [email protected].