Putumayo appraisal drilling, 3D work starting

By OGJ editors
HOUSTON, Oct. 27 -- Consorcio Colombia Energy has started a multiwell appraisal and development program in Pinuna-Quillacinga and Cohembi fields on the 90,000-acre Suroriente block in Colombia’s southeastern Putumayo basin.

Now drilling is Pinuna-3, the first vertical appraisal of the early-2010 Pinuna U pool discovery. The Pinuna-5 discovery well has averaged a gross 2,309 b/d of 29° gravity oil with 12% water cut since coming on line Feb. 11.

The appraisal well targets to extend this pool to the north, said Suroco Energy Inc., Calgary, which holds 15.8% working interest in the block through a subsidiary. Further drilling is planned in the Lower T sand, the other main reservoir in Pinuna field.

Two wells are to be drilled starting in the first quarter of 2011 to offset the single well in Cohembi field. Preliminary results of reservoir simulation work support an interpretation that this pool could grow significantly in size with appraisal drilling, Suroco said.

Cohembi output has gradually increased to an average 1,988 b/d of oil on a larger submersible pump from Villeta N. Cohembi-1 cumulative production is 2.4 million bbl of 20° gravity oil as of Sept. 30, with no significant formation water recovery.

History matching of production and pressure data indicates that the oil-bearing reservoir extends at least 2 km downstructure.

A 3D seismic survey is to start in November on the northern part of the block covering 132 sq km to define potential drill targets along a structural trend that includes Quinde oil pool, a suspended oil well. Drilling could occur in late 2011.