By field geological survey and geological structure study and small fault of the mine roadway analysis, the characteristics，formation mechanism and evolution process were probed into, which of overthrust and decollment structures in Tuoshan coalfield of Xiangzhong depression. The study results show that Ceshui 5 coal in Tuoshan, the lower carboniferous has dynamics condition of well-development bedding structure, and it is the nappe main potential sliding surface of Tuoshan coalfield. The mining area exist gravity sliding cover as well as squeeze the nappe. Sliding cover and nappe structure formed in different periods and different tectonic environment, combined with their own form, and evolution history. The tectonic inversion shows detachment structures in this area has experienced three difference stages: overthrust in the early stage, thrust strengthen in the middle stage, reverse gravity sliding in the late stage.