20 January 2012, Sweetcrufde, ACCRA – United Kingdom’s Tullow Oil, which discovered Ghana’s first oil in 2007, has made another major discovery in the West African nation. This time, it has hit “significant quantities” of light oil in an appraisal well in the Deepwater Tano Block off Ghana.
According to a statement by Tullow’s partner, Kosmos Energy of the United States, the oil was discovered in the Ntomme-2A appraisal well – located about 4 kilometres south of the Tweneboa-3 sidetrack, which earlier discovered the Ntomme field.
The well hit 45 metres of high-quality stacked reservoir sandstones, including 39 metres of 35 degrees API gravity net oil pay, the statement added.
Paul Dailly, Senior vice-president of exploration for Kosmos called the find a “great result” because Ntomme was originally identified as a gas-condensate discovery.
“However, this well confirms the majority of resources to be oil,” he said in a statement.
Ntomme-2A was designed to test the potential for an oil leg beneath the previously identified gas-condensate at Ntomme, Kosmos said.
“Pressure data from the well and the original discovery well suggests the potential for an oil column at Ntomme of approximately 125 meters below the gas-condensate accumulation,” it added.
Operator Tullow drilled the Ntomme-2A well to an interim depth of 3905 metres in water of 1730 metres.
The company is in the process of deepening the well to a total depth of 4010 metres, after which it will run a drill stem test.
Tullow operates the Deepwater Tano Block with a 49.95% working interest. Kosmos and Anadarko Petroluem each own an 18% stake, with Sabre Oil & Gas Holdings on 4.05% and Ghana National Petroleum Corporation on a 10% carried interest.