顾及地球分层的大地测量联合反演模型及应用研究

Based on the geodetic observation signal with combining the geological, seismic and geophysical data, the aim of geodesy inversion mainly focus on inverting kinematics and geodynamics model parameters, modifying and proposing new geodynamics model using the priori geodynamics model from the geophysical research. It also could be used to invert the movement of active faults and blocks from the surface observation data, discuss the relationship between the crust motion and earthquake and make the prediction and forecast on seismic and geological disaster..During the past 20 years the space geodesy observation such as GPS and InSAR techniques provided the more accuracy observed deformation on the earth surface with the rapidly improved technology, which in one hand provide the plenty of raw observed data for geodesy involved in geophysical inversion research, on the other hand a higher demand to more accuracy geodetic inversion model had been proposed out. The new model has to invert out not only the fault dislocation parameters, but also to jointly inverted out the earth model considering the impact of the crustal structure and upper mantle visco-elastic characteristic because of the highly accuracy observed deformation could reflect the influence of the inner crust dynamical movement. We need improve the inversion model to more considerate. .In this project, we firstly want to refine the geodetic inversion model from the dislocation fault model to resolve the earth model including the crust layering and the visco-elastic in upper mantle when using the co-seismic and post-seismic model. The co-seismic deformation inversion model had been proposed out to resolve the fault and earth layering medium parameters together, while the post-seismic deformation inversion model had been formulated to invert out the fault , earth layer medium and upper mantle visco-elastic parameters together. .The inversion algorithm will also be the important research work in this project because the inversion model is very complicated to using the non-linear method rather than combining the least square formulation. Assessing the uncertainties associated with the estimated source parameters remains an important problem since without information about uncertainties. To estimate the individual confidence intervals associated with the inverted model parameters, we employ the bootstrap method in this project..The joint inversion method will be the other research point using the GPS and InSAR observation deformation in this project. Finally we will develop related inversion programs to study the coseismic and post-seismic dynamic mechanism of China and Japan strong earthquake areas with GPS and InSAR observed deformation and make the specific inversion analysis and quantitative interpretation.

大地测量反演是近廿年来新兴的一个学科分支，它以地表运动观测信号为基础，结合数学物理模型和数值模拟方法来认识地球动力学过程，不仅可以揭示构造运动规律， 而且可以认知地震孕育和发生的规律。空间大地测量技术快速发展以及观测精度的提高，一方面为大地测量参与地球物理反演研究提供了丰富的观测资料，另一方面也对大地测量反演模型精确性提出了更高的要求，不仅需要反演断层参数，还需考虑地壳结构及上地幔粘弹性体的影响。本课题致力于研究建立大地测量反演精细模型，拓展大地测量反演方法及理论。通过数值模拟方构法建顾及地球分层结构的同震、震后大地测量联合反演模型，以同时反演研究区域内的断层参数、地壳分层的介质参数和上地幔粘弹性介质参数。结合丰富的GPS/InSAR 观测资料对汶川或日本等重大地震的同震及震后形变进行细致的大地测量反演研究，尽量真实的反演地球内部各种动力学过程，为地震、地质等研究提供定量的解释和分析。

空间大地测量技术快速发展以及观测精度的提高,对大地测量反演模型精确性提出了更高的要求,不仅需要反演断层参数,还需考虑地壳结构及上地幔粘弹性体的影响。本课题致力于研究建立大地测量反演精细模型,拓展大地测量反演方法及理论，结合丰富的 GPS、水准和InSAR等观测资料对近年发生的等重大地震的同震或震后形变进行细致的大地测量反演研究,尽量真实的反演地球内部各种动力学过程。本项目取得的研究成果主要有：.1）考虑地壳分层介质的影响，发展了顾及地壳结构的球体分层同震和震后反演模型，该模型可同时反演发震断层的位错参数和地壳分层介质的体积模量和剪切模量参数及地壳粘滞系数。通过数值模拟反演了走滑断层、倾滑断层和张裂断层的同震和震后形变，结合非线性算法，该反演模型能够反演出两类参数。联合反演的成功率大部分在80%以上，说明本研究建立的同震和震后反演模型基本可靠。.2）基于联合反演中不同数据权比确定的问题，提出了基于方差分量估计的地震同震滑动分布反演方法，该方法不仅可以确定不同数据集的相对权重，而且还能得到平滑因子的值，突破了方差分量估计方法仅用于各类数据定权的实际应用范围。模拟算例和实际算理均验证了方法的有效性，研究结果表明，本文方法相对于线性和非线性混合方法具有计算简单、计算量小和计算效率高的优点。.3）基于上述方法，利用GPS、水准和InSAR等高精度观测资料，分别研究了2011年3月11日Mw9.0日本地震，2007年5月5日西藏阿里地区Mw6.1级地震，2013年4月20日四川芦山Ms7.0级地震的同震断层几何参数及精细滑动分布模型，以及2009年8月28日Mw6.3大柴旦地震的同震滑移及震后余滑分布和其地壳粘滞系数，为研究和探讨相关的地震滑动分布及活动机制提供了定量的解释和分析。.本项目拓展了大地测量反演模型，发展了相关的大地测量反演算法和模型，可为地震预报、地质灾害监测等研究提供定量的解释和分析。