Abstract:The Daba Shan region with its unique tectonic setting and rich petroleum resources is attracting people’s interest to conduct much in depth research. Based on the finite difference method and the elastic plastic constitutive model with two dimensional plane strain, this study carried out a series of numerical simulations for the Daba Shan foreland and thrust belt. The results show that the foreland area has the relatively weak detachment in the Lower Middle Triassic which includes gypsum and salt, which led to the main decollement surface transferring from the lower stratum in hinterland into the higher stratum in foreland. The distribution of Lower Middle Triassic detachment and syntectonic sedimentation put limitation on the position of the Zhenban Thrust, through which strong shortening strain in the hinterland was transmitted from basal detachment of lower Sinian into higher detachment of Lower Middle Triassic. Long term activity of the Zhenba thrust and Chenkou thrust might have accommodated more than half of total shortening strain of the Daba Shan foreland and thrust belt. After syntectonic sedimentation, the shallow Jura type folds in the foreland area propagated forward while those old faults in hinterland continued to thrust and rotate clockwise, thus forming an out of order thrusting sequence. Propagation of the main thrusts, which is different from classic piggyback mode, has shortening strain resulting from subduction of the footwall of main fault deeply into the backland. The simulation results are similar to the geological prototype of the Daba Shan foreland and thrust belt, illustrating that using finite difference software to simulate geological structure is feasible.