| On the basis of the theory of petroleum geology, by means of geology investigations in the field and research indoors, combined with core analysis, logging curve and oil testing, the paper researches Chang2 oil bed rules of distribution of stratum and sandstone, structural feature, rules of sedimentary subfacies, reservoir characteristics, the rules of accumulation and the distribution of oil and gas. The conclusions are listed as follows:1. Chang2 stratum is divided into 3 substratums, includes chang21, chang22, chang23. Chang22 is parted into anther three reservoir sections, includes chang221, chang222, chang223. Chang222 is the sub-main reservoir while chang223 is the main layer.2. Chang22 is super-special low permeability arkose reservoir, with miniature holes and micro throats. Average porosity is 11.24%, and average permeability is 0.8×10-3μm2. On the whole, all the intrastrata, interstrata and plane of Chang 2 oil layer have a strong anisotropy.3. Chang2 formation is confirmed being deltaic front parfacies sediments, It is abvious that underwater distributary channel contrals the depth of stratum.4. The reservoir type is mainly lithologic reservoir. Regularities of distribution of chang2 oil reservoirs are controlled by sand bodies of channels. There isn't edge water and bottom water in oil reservoir because of bad differentiation process between oil and water. The formation pressure is over saturation differential pressure with some elastic energy, and the drive type in Chang2 oil reservoir is elasticity-dissolved-gas drive.5. According to research results and the result of oil test of exploration wells, this paper predicts reservoir distribution of study area.
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