Research On Oil Reservoir Geology Feature Of Jie Faulted Block 2 Of Linnan Depression

By taking upper sha3 Member in Jie Faulted Block 2, Linnan Oilfield as the study case, the reservoir geological characteristics are studied on the base of drilling, logging and analytical data statistics, using sedimentary, logging geology and reservoir geology as the guide.The paper divides upper sha3 Member into 5 layers and 32 sub-layers by using the comprehensive method of contrasting and dividing layers, with the emphasis on sedimentary cycle and multiwell control. The paper makes a good foundation for establishing fine stratigraphic framework models.The reservoir sedimentary microfacies are studied on the base of core description, by using well-logging and well-test data, and by analyzing combined with log facies. According to the analysis of the facies marks, we know that upper sha3 Member is a delta sedimentary system, including delta plain, delta front and delta mud. Delta plain can be further divided into distributary channel, natural levees, crevasse-splays and tributary bay. The sedimentary microfacies of delta front include the underwater distributary channel, underwater interdistributary bay, mouth bar, distal bar and front sheet sand. The sedimentary facies types of non-core are established through the log facies analysis and the sedimentary facies spatial distribution of each layer are analyzed under the control of the stratigraphic framework.The reservoirs are nose structure reservoirs controlled by the downdropped block of Yingzijie fault, and lithologic reservoirs are developed locally. The layer slopes to the north and the region structure is simple. By drawing a single sand top surface of micro-structural map, the paper clarifies the micro-structural types. The main types of micro-structure are identified such as small nose, minor groove and ramp.Sedimentary microfacies control the development and distribution of reservoir, Yingzijie block controls the scale and shape of reservoir, and the microstructures control the distribution of oil. Through comprehensive evaluation, it is considered that the underwater distributary channels and mouth bars are main oil-bearing sand bodies, and the next is the front sheet sands. The southern high structure is the best hydrocarbon enrichment area and the microstructure plays an adjustment function.