Abstract: Steep slope of continental rift lake basin always develops a variety of sand bodies.They interfere with inversion structure recognition because of their particularity of seismic reflection characteristics.With examples of positive inversion folds of Wuhaozhuang fault zone in Gubei Sag and GaoqingPingnan positive inversion fault in Gaoqing areas，the paper analyzes the seismic reflection characteristics of the inversion structure and formation subdivision and correlation with drilling data.The amount of erosion is calculated by acoustic time and tectonic stress characters are determined by fluid inclusions.The seismic reflection characteristics of positive inversion fold appear on the concaveconvex shape in Wuhaozhuang fault zone，and the upper strata are thick in middle，thin in wings.The top of the fold suffers erosion，and reflection events cut significantly.The lower strata preserve filling characteristics of rift basin.Drilling data also show that the anticline core is denuded and acoustic time curve changes significantly in the denuded segment.Two types of inclusions developed in tensional and pressure environment in GaoqingPingnan faults are found.The accuracy of inversion structure recognition is raised with a variety of mutually constraint methods.

Key words: inversion tectonics, acoustic time, fluid inclusions, Jiyang Depression, seismic reflection characteristics