基于非均匀地壳模型的格林函数法反演2001年昆仑山口西Ms8.1地震的同震滑移  

INVERSION OF COSEISMIC SLIP DISTRIBUTION OF 2001 Ms8.1 KUNLUN EARTHQUAKE FROM GPS OBSERVATIONS WITH GREEN'S FUNCTION METHOD BASED ON A HETEROGENEOUS CRUST MODEL

作　　者：周宇[1] 聂兆生[1] 贾治革[1] 陈正松[1] 杨少敏[1] 

机构地区：[1]中国地震局地震研究所(地震大地测量实验室),武汉430071

出　　处：《大地测量与地球动力学》2012年第3期22-26,共5页Journal of Geodesy and Geodynamics

基　　金：中国地震局地震行业科研专项(201208009)

摘　　要：建立基于地壳不均匀的三维有限元模型,将昆仑山口西Ms8.1地震产生的长约400 km的破裂带在走向上分为16段,生成各个破裂段滑移相对于地表位移的格林函数,并以GPS观测的水平位移为约束,用阻尼最小二乘法反演破裂滑移分布,结果表明反演结果与地质考察的地表破裂数据接近。用反演结果重构的地表位移场与观测值一致,并体现了断裂带南北两侧不同的形变模式。2001 Kunlun Ms8.1 earthquake ruptured as long as about 400 km. The displacement gradient per- pendicular to the strike of rupture belt is significantly greater on the south side than that on the north. This fact can- not be explained by Okada model which is based on elastically homogeneous half space. A horizontally and vertical- ly heterogeneous 3D-FEM model is established to generate Green＇s functions of slip on 16 segments of the rupture belt with respect to the ground displacement field. With the damping LS （least square） algorithm, the slip distribu- tion of rupture is inversed from observed horizontal displacements of 40 GPS sites, and the result is in good agree- ment with that from geological field investigation. The ground displacement field rebuilt by the inversed result is close to that observed by GPS, demonstrating different deformation patterns on the two sides of the rupture.

关 键 词：有限元 最小二乘法 昆仑山口西MS8.1地震 同震滑移 GPS 

分 类 号：P315.725[天文地球—地震学]