Abstract:In Qianjiang Depression, China, inter-salt argillaceous dolomite covers an area of 1800km2, and there are 193 cyclothems of grade Ⅲ. According to the third resource evaluation, oil generation volume may have as much as 43×108 tones in the argillaceous dolomite in Qianjiang Depression. And oil resources can reach 1.68×108 tones. The Wangchang area in Qianjiang Depression is considered as the most favorable area for inter-salt argillaceous dolomite reservoir-forming. Inter-salt argillaceous dolomite in the area is a typical unconventional reservoir. "Sweet Spot" is mainly controlled by oil-bearing property and reservoir conditions. Through petro-physics, seismic facies, pre-stack elastic parameter inversion, azimuth anisotropy research, and combined with the geological knowledge, "sweet spots" of 10th rhythm member in Qian 3 oil formation is predicted in Wangchang area.