Geological Modeling Research On Chang 6₂ Reservoir In S160 Well Area Of Ordos Basin

SI60 well area locates in the center of North Shaanxi Slope in Ordos Basin, its main purposed formation of exploration is Chang62 oil layer of the Upper Triassic Yan Chang Formation.In order to master the geology and accumulation characteristic of SI60 well area, this study used sedimentary, reservoir geology, natural gas geology, petroleum entrapment geology and logging geology theory as the instruction, and used geological, logging, production test and measurement test, test oil and production dynamic data as the foundation, combining with various testing methods and analysis approaches, deeply and systematically studied on the formation, structure, sedimentary microfacies types, distribution characteristics as well as reservoir characteristics for this area, and also built a 3-D geology model.Identified the targeted strata developed delta front facies depositional model by research. Underwater distributary channel, distributary bay, mouth bar, far sand dam, these four kinds of microfacies have been distinguished further. Underwater distributary channel microfacies is the skeleton sand bodies of reservoir.According to the research, which is based on drilling core observation and laboratory test datum, Chang62 reservoir belongs to low-especially low porosity, low permeability reservoir. Property becomes better from bottom to top gradually. Considering the reservoir rock types, sedimentary facies, reservoir physical property (mainly for porosity and permeability), sand body thickness, the microcosmic pore structure characteristic, the reservoir in this area are classified as:Ⅲa-Ⅳb type, in which Ⅲa>Ⅲb type are good reservoir of Chang62 in the research district, Ⅲb type is better reservoir. Ⅳa type is medium reservoir, IVb type is poor reservoir.A model is established based on establishing facies-controlled geological model refer to Chang 62 on the basis of the former study and establishing structural model by using hierarchical data. Established a sedimentary facies model by Sequential Indicator Simulation (SIS). Then, facies-controlled modeling could be conducted based on previous sedimentary facies model. The outcomes show that the conditions established by the phased model is more consistent with the reality, and satisfactorily characterizes the properties of the reservoirs with severe heterogeneity as well. It also provides the basis for the further development and accurate assessment of oil reserves.