Publications

Horizontal wells in Attaka, a giant mature field, have proven to be an effective method of arresting production decline where many of the reservoirs are pressure depleted or watered out (swept). Previous studies of select Attaka reservoirs have also indicated that waterflooding will yield an additional 50% more reserves than vertical or non-horizontal wells in depletion/partial water drive reservoirs. This study presents the successful results of a horizontal well in Attaka field and the future plan of waterflooding this sand by injecting down-dip in a converted depleted producing well . Attaka B-2RD2HZ, drilled and completed in October 22, 2006, has been producing for more than 1 year with zero percent water cut. Current production comes from a channel-sand in the middle shallow Miocene geological sequence. Hydrocarbon reserve estimates in this area are supported by reservoir simulation. Actual postdrilling results came in as planned on this 820 ft horizontal lateral producer, with expected primary reserves estimated to be 327 MBOE. Completion was done by slotted liner, and a later gas lift optimization was accomplished by installing a pencil orifice in the XD sleeve to lower the gas lift intake point. The next phase of this reservoirs development is to initiate water injection in the down-dip converted water injector. A successful waterflood will be used as the model for other similar characteristic reservoir in the future.