After the Stena Tay rig drilled the well to a current depth of 3674 metres, the operator Dana Petroleum decided to run a seven-inch casing string due to increasing formation pressure, Roc said.

The rig is now preparing to drill ahead in a six-inch hole to the planned total depth of 4237 metres.

Wireline logging, including pressure measurements and fluid sampling, were completed over the Upper Cretaceous interval above 3536 metres last week.

“Initial interpretation of the data collected indicates the presence of two hydrocarbon bearing sandstones, some 150 metres apart,” Roc said.

“The lower sandstone has a gross thickness of approximately 40 metres of which the upper 10 metres contains a hydrocarbon which appears to be a light oil or a liquids rich gas-condensate.”

But Roc said the precise composition of the hydrocarbon fluids recovered from both zones would not be known until fluid samples were fully analysed in an onshore laboratory.

“It should be noted that the logged interval corresponds to an upper target objective and there is potential for other s ands in the remaining section to the planned total depth,” it said.

Drilled in 1,162 metres of water, Faucon-1 is 140 km south of the Chinguetti Oil Field. The reservoir target is a Cretaceous canyon complex sealed against a salt diapir.

Equities in Block 1 are Dana Petroleum (E&P) Ltd (operator) 60%, Hardman Petroleum (Mauritania) Pty Ltd 18%, Tullow Oil 20% and Roc Oil (Mauritania) 2%.

Meanwhile on the other side of the continent, in Block 2, Uganda, Hardman said mobilisation of the drilling rig at the Mputa-1 wildcat site was complete, with fewer than 10 loads of consumables remaining to be mobilised.

Rig-up is now 85% complete and the Mputa-1 well, which has a planned total depth of 1100 metres, is expected to spud in less than one week.

Equities in Block 2 are: Hardman Petroleum Africa Pty Ltd (operator) 50% and Tullow Oil 50%.