Consulting engineers have issued a best estimate contingent resource of 31.6 million stb for Block 95 in the Maranon basin of Peru, said Gran Tierra Energy Inc., Calgary.
The other estimates for the block are a high of 88.1 million stb and a low of 11.5 million stb, Gran Tierra said.
The 1974 Bretana 10-16-1X discovery well on Block 95 flowed at the rate of 807 b/d of oil, natural, for 6 hr from the Vivian formation. Well records indicate inconsistent oil gravity values of 13.1° and 17.6° gravity.
Since Bretana is in a remote location 160 km southeast of Corrientes oil field, it would be challenging to develop at an oil gravity of 13.1° gravity and would be economic if the oil gravity is 17.6°, Gran Tierra said.
The company plans to drill an exploratory well in the fourth quarter of 2012 to further delineate the field and to explore deeper reservoir horizons not penetrated by the discovery well. A drill site has been identified and civil construction initiated for the Bretana Norte 95-2-1X well.