同震变形分析中不同地球结构模型差异性研究

STUDY ON DIFFERENCE AMONG DIFFERENT EARTH'S STRUCTURE MODELS IN CO-SEISMIC DEFORMATION ANALYSIS

顾及地球结构的非均匀性、分层和球体特性,定量研究了球体分层模型、球体均匀模型、半空间均匀模型分别作用于地震断层(走滑断层,逆冲断层)产生的地表同震变形的差异。计算结果显示,相对实际地球模型,利用半空间均匀位错模型计算的同震变形差异很大,大大超出现有高精度测量技术的精度。如果利用实测资料(例如GPS,VIBL,InSAR等高精度测量数据)进行反演研究,必须根据实际地壳构造情况考虑地壳分层结构的影响。

Considering the inhomogeneousness, stratified and spherical characteristic of earth structure, the co-seismic deformation difference among spherical earth layering model, spherical homogeneous model and half-space homogeneous model has been studied in this paper. The quantitative difference due to the influence by the crustal layering and earth curvature have also been calculated out and compared. The calculation results show that the surface co-seismic deformation difference is so large that exceeding the accuracy of high precise observation technology if not considering the actually earth structure when just taking the earth as half-space homogeneous medium. If one wants to use the high accurate observation data （such as GPS, VIBL, InSAR observations） to do the inversion research, the effect from the stratified crustal structure can not be ignored.