Amerisur Briefs on Colombian Block Operations

Amerisur provided the following update on operations in the Fenix Block, Colombia, further to that provided on March 22.

The 8.1/2" deviated section of Isabel-1 has been drilled to 1854 ft, with a final inclination of 44 degrees. Following logging, which indicated a total apparent thickness of 144ft of sandstones with oil saturation, the 7" casing was run and successfully cemented.

Drill Stem Tests were performed in two zones:

DST#1 was performed over the interval 1121 to 1164 ft. This zone was identified from logs as having high hydrocarbon saturation but relatively poor reservoir characteristics. The zone flowed oil but could not be flowed consistently to surface. However a downhole sample of fluid returned dry oil (0%BS&W) at 34.5 degrees API. This section was subsequently isolated and remains a valid candidate for stimulation at a later date.

DST#2 was performed over the interval 960 to 1040ft. The interval produced light oil to surface under natural flow (32.5 degrees API) through various choke sizes at rates from approximately 150 to 350 BOPD. The well has now been completed as a producer and the Company will apply in the next few days to the Ministry of Mines and Energy for authorisation to begin a Long Term Test (LTT) of this interval.

The Company and its contractors have now sourced the required equipment to re-enter and stimulate the Iguasa-1 well deep section. It is expected that this work will be performed during April.

John Wardle, CEO said, "This is a very good result from Isabel-1, which significantly de-risks the shallow prospect we have mapped within the block. This shallow play, coupled with the deep zone we identified in the Iguasa-1 well represents an important opportunity for the Company to build reserves and production levels."

Giles Clarke, Chairman commented, "Once the LTT begins, Isabel-1 will be the third production well for the Company. We are very pleased with the progress being made."