By OGJ editors
HOUSTON, Jan. 10 -- The Sapele-1 discovery well on the MLHP-5 block of the 2,316 sq km Etinde permit off Cameroon has encountered more hydrocarbon pay in Tertiary and Cretaceous objectives based on drilling, wireline logs, and samples of reservoir fluid and pressure data, said operator Bowleven PLC, Edinburgh.
Bowleven revised upwards its estimate of hydrocarbons in place to 65 to 430 million bbl with a mean of 217 million bbl. The numbers remain subject to revision, it said, as drilling is to continue beyond the present depth of 4,539 m to probe further identified Cretaceous potential.
A principal objective of the well was to prove the concept of the Cretaceous play in the offshore Douala basin. Sapele-1 has now confirmed the presence of reservoir and hydrocarbons in the Cretaceous and extended the Cretaceous play fairway significantly offshore, Bowleven said.
All five of the well’s target objectives are indicated to be hydrocarbon-bearing from log evaluation, and sampling has confirmed net pay in three of them.
Bowleven noted that the location, in 20 m of water, was chosen to intersect multiple independent exploration targets from the proven Miocene fairway down to the deeper Cretaceous fairway from a single drillsite. As a result, a number of the targets have been intersected at suboptimal locations.
“Consequently,” Bowleven said, “while the well has confirmed the prognosed targets as hydrocarbon-bearing, this is believed to have occurred at the extremities of Lower and Deep Omicron and the Cretaceous Epsilon Complex.” The well has drilled through the Cross-cut event and into the Cretaceous.
The well intersected a log-evaluated gross hydrocarbon interval of 18 m in what are believed to be moderate-quality interbedded reservoir sands. The provisional net pay is estimated at 4 m with 17% average porosity.
Meanwhile, the well intersected a log-evaluated 9-m gross hydrocarbon interval of moderate to good-quality reservoir sands in the Epsilon Complex. The Cretaceous net pay encountered to date is estimated at 4 m with 13% average porosity. Fluid samples acquired while logging confirm the presence of lean gas-condensate.
Due to the stratigraphic nature of the Omicron discoveries, further appraisal is required and being planned, Bowleven said. Updated volumetrics for the Epsilon Complex will be generated after completion of the well and integration and evaluation of the extensive well data acquired.
Vitol E&P Ltd. has an initial 25% interest in the MLHP-5, 6, and 7 blocks and has an option to acquire a further 10% interest in MLHP-7. Cameroon has the right to elect to take a 20% participating interest in any development activity, with Bowleven and Vitol reducing their interests pro rata.
The Etinde Permit covers 2,316 sq km in the Rio del Rey and Douala basins. The permit, whose exploration period expires at the end of 2011, has the provision for a 1-year extension for appraisal. The Bowleven group has drilled five successful wells on the permit since 2007.
Photo from Borealis AG.
Photo from OKEA.
