The Remaining Oil Research Of Fuyang Reservior In Xinli Oilfield

The old area of Xinli oilfiled is low permeability and low porosity fractured sandstone reservoir, more longitudinal reservoir development. The interlamination and areal heterogeneity is seriously, the physical property of the Fuyang reservoir is poor. Xinli oilfiled was invested into development in 1983. In the early time, 300 meters well spacing for the inverted nine-spot square pattern was used. In the year of 1997, the well array further adjustments were conducted. Row of adjustment oil/water well were drilled between the two original rows of wells, and by means of crude oil/water wells type traded, linear injection strategy near east-west direction was formation. Until March of 2015, the total numbers of well are 2655. The verified daily oil-producting of Xinli oilfield is 1092 t, composite water cut is 70.23 percent, recovery degree is 19.62 percent. With thoroughly development, the oilfield has entered the “high-yield water, high extraction” stage and the situation are enormous. Into the high water-cut stage, the emphasis and difficulty of oilfield exploitation turn to rediscover and exploit remaining oil.Under the guidance of geostatistics 、 high definition sequence stratihraphy and sedimentology, using the fine individual layer decarcation and comparison means, we build a fine strata framework of the work area. Then interpretate manually for sedimentary facies of every well and every layer to make sure sedimentary facies distritution features. On the base of the research above, the statistical model of the sand body of work area reservoir distribution in the space was confirmed. By the reservoir model building software, a three-dimensional geological model was built. Combining the sedimentary microfacies, a sedimentary model was established. The porosity, permeability and oil saturation modes are built. On combination of the late oil saturation, we can know the distribution of residual oil and profitable layer. The research findings of the interlamination, layer and areal heterogeneity show that the major layers of 8, 14 and 16 have strong serious heterogeneity, which indicates a potential for exploiting remaining oil. At the same time, we introduce reserves evaluation coefficient to make a comprehensive analysis of the scale of the regional reservoirs and single layers, and confirm the higher one among them, in order to provide a reliable support to deploy new wells. The Fuyang reservoir of Xinli Oilfield(old area) has a greater potential on exploiting remaining oil. According to the detailed reservoir geological study and development data, various methods are carried out to study the regular pattern of the remaining oil and forecast the remaining oil in-place, then it is favorable for EOR.