Study on Economic Marginal Limit of Well Spacing Density During Extra-High Water-Cut Stage of Oilfield

In view of Shengli oilfield＇s current situation of high or extra-high water cut and economic efficiency based on oilfield＇s actual data this paper established the quantitative relationship between oil recovery and well spacing density． It takes into consideration the investment on infrastructure and the operating and management spending during investment pay out period etc using the principle of loss-and-gain balance this paper formulated the expression of reasonable well spacing density． This formula has been applied and verified in Shengli oilfield on to high and low permeability reservoir of fifty units altogether which have been classified into two categories high-permeable and low permeable． It provide reliable scientific basis for oilfield development decision making and production operation．