Calvalley Petroleum has spudded the Qarn Qaymah 2 appraisal well on December 6, 2007. The primary objectives of this well were to appraise the Qarn Qaymah 1 basal Kohlan sandstone gas/condensate discovery and to explore for hydrocarbons within the large, underlying granite basement closure. Secondary objectives existed in the Saar-Naifa carbonates. The well was drilled to a total measured depth of 3,975 metres.
As previously announced on January 14, 2008, oil and gas shows were encountered in Qarn Qaymah 2 within the lower portion of the Saar and Naifa formations, which represent secondary zones of interest in the Qarn Qaymah 2 well and for future wells in Qarn Qaymah area. The Kohlan sandstone, which was a primary objective and sits immediately above the granite basement, was penetrated at a measured depth of 3,178 metres. A good natural gas show was displayed over a twelve metre sandstone interval. Gas and significant condensate were previously recovered on a short term test of the Kohlan sandstone in the Qarn Qaymah 1 well. Qarn Qaymah 2 is located 2.1 kilometres to the east of Qarn Qaymah 1.
The casing shoe was set 43 metres into the granite basement at a measured depth of 3,233 metres and drilling continued into the underlying granite basement. The well was deviated at an inclination of up to 72 degrees towards the south to enable Calvalley to drill towards seismic features that may represent potential fracture zones within the large potential basement closure. An additional 747 metres of granite was penetrated below the casing shoe, giving a lateral offset from the casing shoe of approximately 570 metres to the south. The total 785 metre granite basement intersection in Qarn Qaymah 2 equates to a true vertical basement section of 380 metres total vertical depth in the well bore. This demonstrates the presence of a structural closure with hydrocarbon shows in several fracture zones.
Six fracture zones, which are associated with faults or flexures within the granite basement, were encountered with associated hydrocarbon shows. Strong gas kicks were encountered soon after penetrating the granite basement and gas-condensate shows were associated with the first two fracture zones. As the well was deepened, oil was observed in good quantity over the shaker and mud pit from the four fractures. The mud weight indicates the reservoir pressure may be in excess of 5,000 psi.
Qarn Qaymah 2 has encountered excellent hydrocarbon indications while drilling and, depending on test results, may be the first hydrocarbon discovery within the granite basement zone of Block 9. The Qarn Qaymah granite basement is a large structural high and could have a significant volumetric hydrocarbon potential. Other discoveries have been made in the granite basement of the Masila basin which have achieved commercial productivity. The drilling rig will be demobilized following the completion of logging of the granite basement section and a service rig will be moved on site to commence extensive testing of various hydrocarbon horizons within the well.
The well has demonstrated the potential viability of the granite basement structure in Block 9 as another potential hydrocarbon reservoir and additional exploration is intended to be directed toward similar structures.
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