Tullow expands oil reserves in deepwater Ghana block

Sept. 28, 2011
Tullow Oil looks to have proven more oil in its Enyenra oil discovery offshore Ghana.

Offshore staff

LONDON – Tullow Oil looks to have proven more oil in its Enyenra oil discovery offshore Ghana.

The drillship Deepwater Millennium drilled the Enyenra-3A appraisal well in 1,102 m (3,615 ft) water depth in the Deepwater Tano license, encountering oil in good-quality sandstone reservoirs, said Tullow.

Analysis of wireline logs, reservoir fluid samples and pressure data indicate that the well intersected 17 m (55.8 ft) of 35° API net oil.

Pressure data also confirms a continuous oil column of at least 365 m (1,197 ft), and that the oil is in static pressure communication with both the Owo-1 discovery well, 6.5 km (4 mi) to the south, and the Enyenra-2A appraisal well, 14 km (8.7 mi) to the south.

On completion of drilling operations, pressure gauges will be inserted into Enyenra-2A and Enyenra-3A to determine reservoir connectivity.

Deepwater Millennium will leave the Deepwater Tano block in late October to be replaced by the drillship SedcoEnergy. The latter will drill Enyenra-4A well to further appraise the downdip extent of the field, at a location 6.8 km (4.2 mi) south of Enyenra-2A and over 20 km (12.4 mi) downdip from the Enyenra-3A well.

Next up, Tullow expects to drill Enyenra-5A north of Enyenra-3A to test the field’s ultimate updip extent.

Angus McCoss, exploration director, said: "This excellent result demonstrates that we are close to declaring the Enyenra and Tweneboa development commercial. Although the ultimate extent of the fields are yet to be fully determined, confirmation of this up-dip extension and long oil column in Enyenra is very encouraging."

Elsewhere in the region, Tullow expects the result of the Anadarko-operated Montserrado-1 well offshore Liberia to be released during October.

09/28/2011