中文摘要：

基于均匀连续、各向同性、半无限空间中的弹性位错理论，模拟计算了汶川地震引起的地表同震形变场和重力场，并分析了断层参数和地壳介质结构对其影响效应。结果表明：对于地表垂直位移和重力，应用多个子断层面上的非均匀位错模型计算结果和实际观测更为接近，其与运用均匀位错模型计算结果相比提高了近40%；地壳介质分层结构对水平位移场的影响约为2.7%，分层介质模型理论模拟值与观测结果更为接近。

英文摘要：

On the elastic dislocation theory in the homogeniously continuous, isotropic and infinite half-space, we calculated the coseismic deformation field and gravity field caused by the Wenchuan Ms8.0 earthquake and analyzed the influence of the fault parameters and crustal media structure on the deformation and gravity field. It shows that the calculated results with multi-subfaults model are nearly agree with the observed ones and compared to the results with mean dislocation model the accuracy improves to 40%. The effects of layered crustal media model on the horizontal displacement is about 2.7% , the simulation results of layered-medim earth model are more nearly agree with the observed ones.