FORMATION AND IDENTIFICATION OF THE OIL WATER INTERVALS IN FUYU-YANGDACHENGZI PAY ZONE IN THE WEST OF DAQING PLACANTICLINE

Starting from the formation principle of the special reservoir with top generation-bottom accumulation and combining the exploration practices for Fuyu-Yangdachengzi pay zone in the west of Daqing placanticline in the Songliao Basin,the formation mechanism of the water/oil intervals in Fuyu-Yangdachengzi pay zone was discussed in detail.Research shows that the water/oil intervals in Fuyu-Yangdachengzi pay zone formed under the reservoir-forming condition of taking the overpressure of overlying source rock as driving force.Oil mixing with water migrate into the reservoir.Because the pore throat of reservoir is small,gravitational differentiation of oil and water is not good leading to the oil in pore and water in throat.For this low permeation reservoir,the pore configuration is complicated,the oil saturation is low and the distribution of oil and water in pore is special.These make the electrical resistance curve reflecting fluid information and the identification of water/oil intervals more difficult.For this reason,the method of distinguishing water/oil/gas intervals by multiple parameter decrease dimensionality is put forword and achieved a good effect in actual application.