By OGJ editors
HOUSTON, Aug. 18 -- Antrim Energy Inc., Calgary, says it will complete for production two East Causeway wells in the UK North Sea.
The decision followed positive test results for the 211/23d-17z well, which flowed on final test at multiple stabilized rates of up to 7,500 b/d of light, sweet oil at 1,006 psi through a 42/64-in. choke. The oil also has a low gas-oil ratio, the company said.
The well, drilled horizontally and at a high angle through the Middle Jurassic Brent Group of sandstones, intersected several reservoirs in the Ness and Tarbert formations in two separate fault compartments. The Brent group consists of the Oseberg main reservoir and the Rannoch, Etive, Ness, and Tarbert formations.
This second and final test, performed on the Ness formation in the western fault compartment, is similar to that recovered from the initial test announced Aug. 3. The first test recorded stabilized rates of as much as 7,000 b/d of sweet, 32° gravity oil from the Tarbert formation, also from the western fault compartment. No water was tested from either zone. The Ness formation consists of a series of delta plain channel sandstones braided with coal beds. Sand lobes vary in width from 50 to 400 m and in thickness from 1.5 to 15 m.
The test rates do not include the 8,100 b/d of oil flow rate previously recorded from the Ness formation in the suspended 211/23b-11 well in the eastern fault compartment. It is Antrim's intention to complete for production the well from the Ness formation in the eastern fault compartment. This Ness reservoir was also intersected by the 211/23d-17z well but was not tested.
Antrim, which operates the wells and holds a 65.5% interest, will now analyze the flow rate and pressure data from the tests to assess the full productivity and reserve potential of the Ness Sandstone intersected by both wells, the two zones tested by 23d-17z, and several other zones that remain untested in 23d-17z.
Log data through the horizontal section of the well bore indicates a net pay of 77 ft, rather than 57 ft as reported July 24.
The 23d-17z well also is being suspended, pending final development, and the drilling rig was to be released this week.