Study On Geological Characteristics And Remaining Oil Distribution In Wuxingzhuang Reservoir

The Wuxingzhuang oil field is located in the western Yishan slope of Ordos Basin. The oil field has the characteristics of low porosity, low permeability, complex oil-water distribution, low degree of reserve recovery and larger remaining oil reserves etc. Currently, the geological research work in the study area is not comprehensive, and the remaining oil distribution is unlear. We carry out a series of studies to solve these problems. The technical route in this paper is based on the combination of static and dynamic, geology research and reservoir engineering analysis, qualitative analysis and quantitative calculation. According to the technical route we have studied the Wuxingzhuang reservoir geological characteristics and have illustrated the distribution characteristics and the control factors of remaining oil.Through meticulous stratigraphic classification and correlation of stratum. original Chang8would be parted further. Chang8is devided into3small layers which including Chang81. Chang82-1and Chang82-2. The research of structural feature has shown that the Chang8strata is gentle monoclinal structure. Through the research on the area of microstructure we found that it plays a significant role in remaining oil distribution.Divided the sedimentary microfacies using the sign of the sedimentary facies, and identified the distributary channel, mouth bar, sheet sand etc. We have researched the profile and plane distribution characteristics of microfacies. At the same time, we establish the three-dimensional geological model of the sedimentary using the deterministic method in the study area. Through the analysis of the relationship between sand structure and oil-water movement, describes the control function of sedimentary microfacies about the remaining oil.Based on the core observation, the analysis of laboratory and logging data, the reservoir petrology characteristics, reservoir space characteristics and four-property relationship are studied. According to the results of previous logging parameters, the reservoir lower limit is determined and the oil-water layer identification chart is established. According to the above research we have checked the log interpretation results and completed the reserves recalculation. On this basis we have studied the characteristics of reservoir distribution and its influence on remaining oil. At the same time we used sequential gaussian simulation method to establish the reservoir parameter model. The results showing that Chang8layer heterogeneity is intense, and Chang8reservoir is low porosity, low permeability; According to the above study we have summarized the control function on remaining oil distribution about reservoir sand body and reservoir heterogeneity.We have researched the original oil-water distribution characteristics in the study area, and the Wuxingzhuang region of Chang8reservoir geological reserves is7.122million tons. So the Chang8reservoir is a small, low abundance, low yield and semideep strata’s lithologic deposit; Based on the above research, through the dynamic analytic method and the comprehensive geological methodology, we have carried forecast on the oil deposit’s remaining oil distribution, and the remaining oil distribution of Chang82"1and Chang82-2have a clear understanding. Through the above research work, we know the Wuxingzhuang oil field geological characteristics and Chang8reservoir remaining oil distribution feature systematically. According to the knowledge we have obtained a series of research methods, the methods are helpful to other remaining oil distribution prediction in similar reservoirs.