SANDBOX SIMULATION OF SALTROCK PLASTIC FLOW CONTROLLED BY FAULTS IN THE KUCHE DEPRESSION OF THE TARIM BASIN AND ITS INFLUENCE ON OVERLYING STRATIGRAPHIC STRUCTURES

Taking the Beiqiu Anticline in the Kuche Depression of the Tarim Basin as the actual structural style of the simulation experiment,the Cenozoic rock and saltrock were sampled and analysed for lithomechanical parameters (i.e.,elastic modulus,Poisson's ratio,compressive strength,etc.). By theoretical calculation and experiment,vaseline and loose fine sand were chosen as experimental material based on the similarity principle. Using the bilateral-compressive model. the saltrock plastic flow controlled by faults and its influence on overlying stratigraphic structures were simulated in a sandbox. The results revealed that a) the structural style of the Beiqiu Anticline type in the Kuche Depression was formed by underlying saltrock plastic flow under the control of faults,and the plastic flow of saltrock and the formation of overlying caprock structures were closely related to the time and velocity of tectonic processess,displaying brittle in the rapid and short-time process or plastic in the slow and long-time process;b)the boundary occurrence of faults was one of the major factors controlling the direction of saltrock flow;c) the change of saltrock thickness was jointly affected by plastic flow and tectonic processes,and complex structure deformation existed within the inner of saltrock;d) the salt-rock interaction was not well coordinated,and the "disjunctive" appearance was shown in the boundary;and e) the lithomechanical properties of underlying rock layers affected and controlled the development of overlying rock structures,though the overlying strata may have the identical lithomechanical properties.