A block with three legacy oil fields in shallow water offshore Ghana holds 500 million bbl of oil and 282 bcf of natural gas in place, according to an independent assessment reported by Erin Energy Corp., Houston.
The assessment covered the 373,000-acre Expanded Shallow Water Tano (ESWT) block, for which Erin signed a joint operating agreement for a 2-year initial exploration period last January. Erin subsidiary Camac Energy Ghana Ltd. is operator.
The block encompasses South Tano field, discovered in 1978 by Phillips Petroleum; North Tano field, discovered in 1980 by Phillips; and West Tano field, discovered in 2000 by Dana Petroleum. The fields are 9-21 miles offshore in 180-380 ft of water.
The ESWT block is north of giant Jubilee oil and gas field operated by Tullow Oil PLC (OGJ Online, Aug. 17, 2015).
The ESWT assessment considered results of 14 wells drilled by prior operators, many of which were flow-tested with oil and gas to surface. Test rates ranged from 600 b/d to 2,047 b/d of 15°-32° gravity oil. Erin said tests established a maximum gas flow rate of about 13 MMcfd.
Erin said it and partners are considering development options. A declaration of commerciality, it said, “is expected within the next few months.”
Development drilling could begin as soon as 2017.
Block interests are Erin and Ultramar Energy Resources Ltd., 30% each; Ghana National Petroleum Corp., 25%; and Base Energy Ghana Ltd., 15%.
