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Ordos Basin, ranked second in the Great Basin, has a wealth of potential oil and gas reserves. In recent years, with the in-depth exploration and development of oil fields, southern Mesozoic area found a hundred million ton oil field, oil and gas exploration prospects in the area also caused great concern. Thus, the deepening understanding of the geology, and comprehensive utilization of the rock thin, logging data, combined with the test results, to carry out a detailed study of sedimentary petrology, and fine reservoir evaluation, objective and reasonable evaluation and reservoir analysis of the sand body forecast , looking for the enrichment of the local oil and gas, high-yield block, pioneering the exploration of new areas is particularly important. The rock theory based adhere macro and micro combined, through rock thin section analysis, combined with scanning electron microscopy, electron microprobe, X-ray diffraction analysis of a variety of methods to study the characteristics of the reservoir rock, the rock is divided into conglomerate, in coarse sandstone, fine sandstone, siltstone, shale types and analyze the variation of the area mineral constituents in maturity. Comprehensive utilization of logging data, the combination of tectonic and sedimentary history of the basin, sedimentary facies, microfacies division, four major sedimentary facies: alluvial fan facies, delta facies, lacustrine, fluvial development of the study area. Based on physical properties of reservoir sand bodies of different sedimentary environments: the best reservoir channel sand body underwater distributary channel sand body, followed by underwater distributary river end of the sand bar sand body reservoir sand bodies worst distal bar sand body and lacustrine sand body. Clay minerals and their evolution characteristics important symbol of the division of diagenesis, organic maturation process, oil and gas generation, the formation of new minerals, has a very close relationship between the degree of development of secondary porosity. Summarizes the evolution characteristics of clay minerals in the area, study area, pore type and characteristics of evolution, pore types of primary porosity and secondary porosity, depth of 1300m-1500m and 1700m-1900m for the development of secondary porosity segment. Extend the group type and stage of diagenesis, compaction, precipitation of new minerals and cementation in the organic matter in the immature stage times mature, dissolution and secondary porosity development in the organic maturation early. Secondary pore zone as a bit of favorable reservoir layers. The study of reservoir rock components, structure and reservoir characteristics summarized into five types of oil and gas reservoir-cover types in the study area, the combination has been divided: self-generated swells on the self-storage type, storage type, gave birth to storage, and favorable section predicted.
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