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Fuxian area is located in the southern part of the Ordos Basin, Ordos Basin is located in the western part of the North China platform craton superimposed basin, is one of China's most important petroliferous basins basic structural form of the north west tend to monoclinic. Over the past ten years has experienced several years exploration practice in the area from the Paleozoic to Lower Paleozoic have found several sets of oil and gas bearing system, extend the group is one of the exploration target, through the distribution of depositional systems, Reservoir characteristics and effective reservoir distribution studies have shown that Fuxian area Yanchang as a low porosity and permeability, flat and vertical lithologic reservoir heterogeneity. In this thesis, by core observation sheet identification, physical property data, scanning electron microscopy analysis of statistics, combined with the well logging data and the results of previous studies, the use of sedimentary petrology, reservoir sedimentology, geophysical logging disciplines. Theory and Methods, systems research Fuxian area Yanchang reservoir characteristics, reservoir control reservoir development factors and a comprehensive evaluation. Studies have shown to extend the group's main producing formation in the area for the long paragraph 8 ~ 2 paragraphs long, long paragraph 8 mainly delta front sand deposition, 7-segment long, narrow long paragraph 6 of the lake area, delta front phase turbidite fan deposition and development; 45 sections of the lake basin area continues to shrink, early development for the delta plain; the long paragraph 3, Section 2, long lake basin gradually disappearing, developed delta plain deposits. Petrologic characteristics of the area, pore type, pore structure, and four sexual relationship study concluded that: Yanchang sandstone reservoir rock types are mainly fine-grained feldspathic sandstone, lithic arkose, lower component maturity and textural maturity, with an average porosity of 9.3%, the average penetration rate of 0.46 × 10-structure and physical property parameter in acidic volcanic reservoir, the overall performance for low porosity, permeability, fine pore throat sorting poor characteristics, residual intergranular porosity is the The reservoir's main reservoir space, followed by dissolution pores. Flakes observation and analysis of the physical properties constructive diagenesis, including dissolution, fracturing, and secondary chlorite rims, quartz cementation suppression increased support and protection of the reservoir porosity, resulting reservoir deterioration of the physical properties of destructive diagenesis compaction, cementation of carbonate cementation, illite clay minerals, sandstone deposition of particle size, sand body thickness and sedimentary microfacies planar distribution control storage layer development, good reservoir properties distributary channel microfacies deposited, followed by the mouth bar, distal bar. Comprehensive study indicates Fuxian area Yanchang sandstone reservoir porosity lower limit of 8%, the penetration rate of the lower limit of 0.1 × 10-structure and physical property parameter in acidic volcanic reservoir reference Changqing Oilfield Yanchang classification of low porosity and low permeability reservoir divided Ⅰ class, Ⅱ, Ⅲ, Ⅳ class, Ⅴ, Section 2 (non-reservoir), Section 2, paragraph 8 of the Chang ~ long developmental class Ⅲ class IV reservoir, which is only three paragraphs long, long development of a small amount of storage better set of physical properties of class II reservoir. According to the planar distribution of effective reservoir thickness of each layer and the storage coefficient, and sedimentary facies distribution of the study area, the reservoir enrichment patterns Reservoir Evaluation of the district, and in the current exploration results achieved and the understanding of the basis on the long paragraph 8, Chang 6 and Chang 3 of favorable exploration area forecast.
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