The reef and shoal facies reservoir in Changxing Formation, Upper Permian, is located in Kaijiang-Liangping intraplatform trough. According to the analyses of core observation, thin sections and sedimentary facies and by using geology, bore wells and seismic data, the electrofacies and seismic facies models are established to recognize the reef and shoal facies reservoirs. The chimney effect which is used to confirm the mess of wave resistance, interception and pulldown in seismic cross section is an effective sign of looking for reef and shoal facies reservoirs enabled gas reservoirs. Based on it, reef and shoal geologic model acting to seismic inversion constraining condition of predicting favorable reef and shoal facies zone, combined with the thickness distribution map of dolomites, the favorable area for reservoir evaluation is estimated.
