Abstract: Under the guidance of Changxing platform margin reef reservoir cognition, combination of the 3D and 2D seismic data, analysis of the sedimentary background, development model & ancient physiognomy were studied comprehensivly. In this study, evolution characteristics of reef in Pengxi-Wusheng depression edge in the middle of Sichuan Basin were analyzed, and three development models of reef in Tailai, Yongxingchang and Yihe depression edge in southeast of Sichuan Basin were put forward. Affected by North Kaijiang-Liangping shelf, Emei taphrogenesis & micro-palaeogeomorphology, the reef deposited dominately in depression edge in Tailai,low-energy bioclast-shoals deposited in Yongxingchang and row reef belt and patch reef developed in Yihe. Analysis of sedimentary pattern of Sichuan Basin during Changxing period, the deposition patterns of reef in Pengxi-Wusheng depression edge and Kaijiang-Liangping shelf margin were similar. The vertical developments of reef were in small scale, but the horizontal area distributed widely in depression edge.

Key words: Sichuan Basin, Late Permian Epoch, Pengxi-Wusheng depression, sedimentary comparison of reef