LONDON (Dow Jones)--Independent oil and gas company, Gulf Keystone Petroleum Ltd (GKP.LN), Monday announces the start of workover and testing operations on the Shaikan-1 discovery well. MAIN FACTS: -Will execute the following work program in the given sequence: -1. Zone three: Re-test the Butmah (lower Jurassic) formation, from 1,783 meters to 1,814 meters depth in the well. -A very high permeability but low energy zone due to low gas content. -The zone, which originally lacked sufficient energy to flow to surface, will be re-tested using a 350 hp Electric Submersible Pump, or ESP, that will more adequately test the inflow capabilities of this zone. -2. Zone two: Re-test the Mus (upper Jurassic) formation, from 1,627 meters to 1,667 meters. -This is also a very high permeability zone with little reservoir energy due to the general lack of associated gas (low gas-oil-ratio or "GOR"). -This zone, which originally tested at 120 barrels of oil per day, or bopd, will also be re-tested using the same 350 hp ESP. -3. Zone one: Complete the well for long term production testing (18 to 24 months) in the original discovery zone, the Sargelu (upper Jurassic, 1,450 meters to 1,510 meters). -This zone has a higher GOR, in the range of 120 cubic feet of gas per barrel of oil, and demonstrated natural flow rates of almost 7,500 bopd, despite the limitations of the original test equipment. -It is the current intention that this production will be processed, through the facilities currently being constructed, and sold. -4. Drill an appraisal well through the Cretaceous intervals, 50 meters to the east of the existing Shaikan-1 well. -Much of the Cretaceous age interval could not be properly logged and evaluated during the initial drilling of the Shaikan-1 well due to a lack of drilling mud returns. -Evaluation of small portions of well logs from the initial drilling would seem to indicate that the Cretaceous intervals may hold significant quantities of recoverable oil. -These oil volumes could be substantial (estimated by Dynamic Global Advisors at more than 700 million barrels of oil-in-place) and were not fully taken account of in current resource estimates. -Test zones 4 and 5, which flowed 1,700 bopd and 10,000 barrels of oil equivalent, or boepd, will not be re-entered. -The entire workover and drilling program is estimated to take four to five months to complete. -Shares closed Friday at 68.0 pence. -By Iain Packham, Dow Jones Newswires; 44-20-7842-9269; [email protected] (END) Dow Jones Newswires July 12, 2010 02:18 ET (06:18 GMT)