Colombia: Llanos well cased for multizone tests

March 10, 2011
Petroleo Brasileiro SA has cased the Balay-2 ST1 well on the Balay block in Colombia’s Llanos basin 160 km east of Bogota.

By OGJ editors
HOUSTON, Mar. 10
– Petroleo Brasileiro SA has cased the Balay-2 ST1 well on the Balay block in Colombia’s Llanos basin 160 km east of Bogota.

The well went to a total depth of 15,084 ft true vertical depth, said 15% interest owner Petroamerica Oil Corp., Calgary. Petrobras is operator with 45%. Cepsa Colombia SA has 30%, and Sorgenia has 10%.

The original objectives of the Balay-2 well were to appraise the 2010 Balay-1 Mirador formation discovery and to assess the hydrocarbon potential of the deeper Barco, Guadalupe, Gacheta, and Une formations that could not be properly evaluated in the Balay-1 well for operational reasons.

Logs at Balay-2 ST1 indicate a probable 50 ft of net oil pay in Upper Mirador, compared with 20 ft in Balay-1. Oil shows were observed while drilling the deeper reservoirs.

Balay-1, on long-term test since July 14, 2010, and has recovered more than 200,000 bbl of 28° gravity oil from Upper Mirador under natural flow with 0.2% BS&W. Present rate is 1,378 b/d on a 48/64-in. choke.