London listed Tullow Oil says August and September’s Jethro (MEES, 16 August) and Joe (MEES, 20 September) discoveries on its Orinduik deepwater block off Guyana, were of “heavy crudes with high sulfur content,” potentially complicating the prospects for commercial development. Qatar Petroleum (QP) in July bought a 10% stake in the block from Total (15%), as well as 10% of the adjoining Kanuku block where Spain’s Repsol operates (MEES, 2 August).

“Tullow and the Joint Venture Partners are assessing the commercial viability of these discoveries considering the quality of the oil,” the London-based operator (60%) says in a 13 November update that suggests an expectation the crude will require special processing to render it saleable. Crude containing high concentrations of sulfurous compounds typically needs processing before it can use regular pipelines, whilst extra-heavy crude can need heating to enable it to flow – both types of treatment are of course more challenging for deepwater offshore discoveries. (CONTINUED - 283 WORDS)