Zarat well strengthens development prospects

Sonde Resources has completed drilling and production testing of the Zarat North-1 appraisal well on the 7th of November block, offshore Tunisia/Libya.

Offshore staff

CALGARY, Canada -- Sonde Resources has completed drilling and production testing of the Zarat North-1 appraisal well on the 7th of November block, offshore Tunisia/Libya.

Jack Schanck, president and CEO, said: “We are very pleased with the robust test results from this well, and the thickness of the hydrocarbon column, which was about twice that originally estimated for this location.

“Our near-term engineering studies will include reviewing the use of horizontal wells for developing the field, which may result in significantly higher production rates and recoverable reserves per well, given the high quality of reservoir rock encountered.”

The well was drilled vertically to a TD of 9,728 ft (2,965 m), encountering 240 net ft (73 m) of pay in the Eocene El Gueria limestone. After being cased to TD, three production tests were performed through a 2 ¼-in. diameter test string, from 42 ft (12.8 m) above the water contact to 177 ft (54 m) above the water contact.

Sonde says all three tests flowed substantial quantities of gas and condensate, with the second test yielding sustained rates of around 750 b/d of condensate and 8 MMcf/d of gas. At peak, Test 2 flowed 1,100 b/d of condensate.

Tests 1 and 3 brought sustained rates of roughly 600 b/d of condensate and gas rates of 8–11.5 MMcf/d. All the tests produced water at rates from 200-350 b/d. This included both drilling fluids and formation water, with water decreasing and oil increasing throughout the tests, Sonde said.

The well was drilled 2 km (1.25 mi) northeast of Marathon’s Zarat-1 discovery and 3 km (1.9 mi) northeast of the Zarat-2 appraisal. It encountered gas/oil and oil/water contacts at the same structural elevation as the Marathon wells. According to Sonde, this indicates a significant extension to the previously-proven accumulation, which could be economic to develop.

Management is reviewing recoverable reserve scenarios, options, and cost estimates for development of the Zarat field, and also will investigate unitization options with PA Resources, which has an operating interest in part of the field immediately south of the 7th of November block. Sonde may also look to bring in farm-in partner to help finance development.

The well will be temporarily abandoned for potential re-entry in a future development.

01/12/2011

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