Pacific Rubiales announced new exploratory success at its Guairuro-1 stratigraphic well (the "Guaiuro-1 Well"), located in the CPE-6 Block, in the Llanos Basin, Colombia. The CPE-6 Block is a Special TEA awarded in 2008 by the ANH, in which Meta Petroleum (a wholly-owned subsidiary of the Company) is the operator and holds a 50% working interest. The remaining 50% is held by Talisman (Colombia) Oil & Gas, a wholly owned subsidiary of Talisman Energy.
The Guairuro-1 Well reached a total depth of 3,495 feet measured depth (MD), or 2,658 feet true vertical depth below sea level (TVDSS), and found the top of the C7 interval of the Carbonera Formation at 3,229 feet MD, or 2,392 feet TVDSS, the Mirador Formation (Basal sandstones) at 3,332 feet MD, or 2,495 feet TVDSS, and the top of the Paleozoic Basement at 3,428 feet MD, or 2,591 feet TVDSS.
The well was drilled with a 6 1/8" slim design, and was continuously cored along the main exploratory objectives, the Carbonera C7 interval and the Basal Sandstones of the Mirador Formation, obtaining a core recovery up to 145.7 feet (66%) from a total cored section of 220 feet. The cores are presently being analyzed and the results will be used to complete the evaluation of the exploration potential of this block.
The petrophysical analysis of the well indicates a net pay zone of 28 feet with 28% average porosity, and has identified oil bearing sandstones down to 3,377 feet MD, or 2,540 feet TVDSS, resulting in an oil column of 45 feet gross at the well.
The results from the Guairuro-1 Well confirm the presence of hydrocarbons in the region and reinforce the exploratory potential of the CPE-6 Block. The well cores also showed evidence of possibly lighter oil in two intervals at the Carbonera C7 sands, which may indicate that oil accumulations at these upper levels could also extend to the northern portion of the CPE-6 Block.
Since the Guairuro-1 Well is a stratigraphic well, and cannot be tested for long-term production potential, the Company is preparing the well to perform pressure tests on 30 levels, from C-7 to the Basal Sandstones of the Mirador Formation, and collect two fluid samples from the upper C-7 intervals.
The Guairuro-1 Well is the first of the six stratigraphic wells to be drilled in the Block in 2010. The Company is now planning to drill five additional wells during the third quarter to honor the minimum work program committed on this Contract.
At this block, the Company wanted to investigate the regional extension of the Basal Sandstone play found in the Rubiales and Quifa Blocks, which are located approximately 100 km to the east-northeast of the CPE-6 Block. The interest of the Company in the CPE-6 Block was based on the information provided by 4 wells drilled during the early 1980's - Manacacias 1 & 2, Los Kioskos 1 and SM-5. These wells showed oil bearing sandstones in the northern part of the block and these oil-bearing sandstones were interpreted to represent the same play found on Rubiales and Quifa. Three of the wells were tested (Manacacias-1 & 2 and Los Kioskos) but were plugged and abandoned because, at the time, they were considered uneconomic due to the gravity of the oil (10.5 to 12 degrees API) and the distance of the wells from any production facilities, which made the operating cost extremely high. The fourth well, SM-5 was abandoned due to a mechanical condition that did not allow for it to be tested.
The Guairuro-1 Well exhibited oil-impregnated cores in every single sandstone from Carbonera C-7 down to 3,377 feet MD within the Basal Sandstones (Mirador Formation), indicating that oil had enough mobility to reach, possibly through faults, more than 100 feet vertically from the basal sandstones into the C-7 units.
Based on the petrophysical results of the Guairuro-1 Well, the Company decided to re-evaluate the petrophysical parameters on the previous four wells and found net pay intervals on the basal sandstones varying from 20 to 38.5 feet, and porosities ranging from 25.5 to 28.6%.
The revised petrophysical evaluation on wells Manacacias 1 & 2, Los Kioskos, SM-5 and the new information from Guairuro-1 Well (especially the net pay and the depth of oil water contacts identified in all five wells), additional to the seismic interpretation of the stratigraphic pinch-out of the Basal Sandstones, has allowed the Company to re-map the prospect on which those five wells are located and has established that the possible area for the stratigraphic trap can reach at least 100 km(2) (25,200 acres from the pinch-out to the average oil-water contact). This acreage corresponds with the existence of a regional belt of heavy oil that may extend further northeast and reach the Rubiales-Quifa areas.
As part of the work commitment for the CPE-6 Block, the Company recently acquired 678 km of 2D seismic lines focused on the northern part of the block where the stratigraphic trap was identified. This new seismic information is currently being processed and will be integrated with the existing data to re-map the stratigraphic trap. The new interpretation will be used to identify the locations for the next five wells that need to be drilled during the third quarter of 2010.
The Company, as the operator of the Rubiales and Quifa heavy-oil fields, has the proven expertise to put into commercial production heavy oils. Accordingly, with this new information on the CPE-6 Block, production should be underway once the Company elects to convert this Special Technical Evaluation Agreement (Special TEA) to an Exploration and Production contract. Conversion will be requested of the Colombian National Hydrocarbon Agency (ANH) once the Company completes the exploratory commitments mentioned above and defines the area with the highest exploratory potential and subject to the technical evaluation of the TEA Area.
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