Controlling technique for water coning in thin oil reservoir with bottom water in Luliang Oilfield

A new technique for building gel barrier without reperforation to block bottom water was proposed. This technique took fully advantages of selective plugging effect of water-based blocking agent and gravity segregation resulted from density contrast of oil and water and could control water coning by gel barrier in vicinity of oil-water interface. Three operating fluids including high-density brine, gellant and over-displacing fluids were used for this technique. The behaviors of these fluids and their construction process were tested and theoretically researched. Since October 2003, eight oil wells in thin oil reservoir with bottom water in Luliang Oilfield have been constructed using this technique successfully. By August 2005, the oil production of these wells increased by 2622 tons, and the water production decreased by 4968 cubic meters. Declined water cut of mass production ranged from 11.3% to 38.4%. The result of field experiment confirmed that the technique is effective for controlling water coning in thin oil reservoir with bottom water.