利用大地测量数据反演地震位错Love数和格林函数的理论与方法

The theory and method of determining dislocation Love number and Green′s function using geodetic data

本文提出一种利用大地测量观测技术反演地震位错Love数及格林函数的理论和方法.首先根据地震位错理论建立理论同震变化和大地测量观测值之间的关系式;其次,以2011年Tohoku-Oki地震(M W9.0)为例,反演体现局部构造特征的地震位错Love数和格林函数.结果表明:反演得到的位错Love数与PREM模型下的位错Love数随深度和阶数变化不同,反映出局部三维地球模型的构造差异,由此计算的同震变化跟实际大地测量观测值的吻合度提高了~60%~~80%.通过大地测量观测数据反演的地震位错Love数能体现局部地球真实的构造信息,为该地区地震研究提供更加精确的地震位错格林函数.

This paper proposes a theory and method of determining dislocation Love number and Green′s function using geodetic observation data.Firstly,we establish the formula between theoretical deformation and geodetic observation.Then,a case study of the 2011 Tohoku-Oki earthquake(M W9.0)is used to invert the dislocation Love number.The inversion results show that there are differences between the dislocation Love number and the PREM model with depths and degrees,which reflects the local three-dimensional structural characteristics of Earth model.And the coseismic change calculated from our result coincides with the actual geodetic observations by^60%to^80%.The dislocation Love number estimated from geodetic observation data can better reflect the real local structural information of the Earth and provide more accurate dislocation Green′s function for earthquake research in this region.