提出描述断层滑动和转动的向-位错组合模型。利用实测的2008年汶川大地震GPS同震数据,基于向-位错组合模型,采用粒子群算法反演了主破裂带的三维滑动和转动,并将滑动结果与前人成果进行对比,最后由正演计算进一步验证反演结果的可靠性。理论分析和模型计算结果表明:1)震源破裂的主要特征是逆冲兼右旋走滑;2)龙门山断裂的滑动和转动有明显的分段性特征;3)汶川地震的地震矩为7.069×10^20Nm,矩震级为7.899。向-位错组合模型反演结果与前人成果保持了很好的一致性。
In order to study the three-dimensional movement of Longmenshan fault, the disclination-dislocation model of describing fault slip and rotation is proposed and used. The three-dimensional sliding and rotation of the main rupture zone is inverted with the particle swarm optimization metho- dand by using the measured data of GPS co-seismic data from 2008. The sliding results are contrasted with previousresearch results, and finally the reliability of the inversion results is further verified. The theoretical analysis and model calculation consequents illustrate that: firstly, the main feature of the source rupture is reverse thrusting and dextral strike-slip; secondly, the sliding and rotation of Longmenshan fault has obvious segmentation characteristics; thirdly, the seismic moment Mo is 7. 069×10^20Nm and the Mw is 7. 899 of Wenchuan earthquake. The inversed results by using the disclina- tion-dislocation model are consistent with previous studies, therefore, the model is applicable for studying the fault activity.