| 芦山MS7.0级地震InSAR形变观测及震源参数反演 |
| |
| 引用本文： | 刘云华,汪驰升,单新建,张桂芳,屈春燕.芦山MS7.0级地震InSAR形变观测及震源参数反演[J].地球物理学报,2014,57(8):2495-2506. |
| |
| 作者姓名： | 刘云华 汪驰升 单新建 张桂芳 屈春燕 |
| |
| 作者单位： | 1. 地震动力学国家重点实验室, 中国地震局地质研究所, 北京 100029;2. 深圳大学, 深圳 518060 |
| |
| 基金项目： | 国家自然科学基金(41340008);中国地震局地质研究所基本科研业务专项(IGCEA1104)共同资助 |
| |
| 摘 要： | 2013年4月20四川省芦山县发生MS7.0级地震，目前的研究资料表明地震发生在龙门山断裂南段，但地表未发现明显破裂.本研究利用InSAR技术与Radarsat-2雷达数据，获取了芦山地震同震的部分形变场，结果表明，近场区域的LOS位移发生视线向隆升，量值在7 cm左右.随后利用弹性半空间的位错模型反演了断层面参数，综合反演结果及震源机制解最终确定了发震断层的初始模型，以形变场观测数据为约束，基于梯度下降法反演获得了断层面上的滑动分布，反演得到的矩震级为Mw6.45级，断层走向213°，倾角39°~43°，最大滑动位于地表以下约13 km深度位置，最大滑动量0.91 m，平均滑动角71°，整体上仍以逆冲滑动为主，兼具左旋走滑.推测在双石-大川断裂以东12 km处展布一条隐伏断裂，为本次的发震断裂.
|
| 关 键 词： | 芦山地震 InSAR形变场 震源反演 滑动分布 |
| 收稿时间： | 2014-04-18 |
Result of SAR differential interferometry for the co-seismic deformation and source parameter of the MS7.0 Lushan Earthquake |
| |
| LIU Yun-Hua,WANG Chi-Sheng,SHAN Xin-Jian,ZHANG Gui-Fang,QU Chun-Yan.Result of SAR differential interferometry for the co-seismic deformation and source parameter of the MS7.0 Lushan Earthquake[J].Chinese Journal of Geophysics,2014,57(8):2495-2506. |
| |
| Authors: | LIU Yun-Hua WANG Chi-Sheng SHAN Xin-Jian ZHANG Gui-Fang QU Chun-Yan |
| |
| Institution: | 1. State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029, China;2. Shenzhen University, Shenzhen, 518060, China |
| |
| Abstract: | On April 20 2013,a magnitude MS7.0 earthquake struck the Lushan County,Sichuan Provinces. At present studies showed that the earthquake occurred on the southern segment of the Longmen Shan fault zone, where no obvious surface rupture was found. In this research, we obtained the co-seismic deformation along line of sight of this earthquake using SAR interferometry technique and Radarsat-2 data. The result indicated that about 7 cm uplift was measured near the fault zone, and the uplift may be induced by the action of squeeze stress when Longmenshan nappe structural zone thrusts from southwest to northeast, and is blocked by the Sichuan basin. Then the coseismic displacements were inverted to build uniform dislocation model. We determined the primary fault model. Based on the InSAR measurements and the steepest descent method, we used Okada homogeneous elastic half space model to calculate further distributed slip model. The inverted geodetic moment is approximately Mw=6.45, with a maximum slip of 0.91 m mainly occurred at depth of 13 km, and a rake of 71°, which is dominated by thrust movement. From the fault parameter strike 213°and dip 39°~43°,we deduce that there is an blind fault extending 12 km east of the Shuangshi-Dachuan Fault, which is the seismogenic structure of this event. |
| |
| Keywords: | Lushan Earthquake InSAR co-seismic deformation field Source inversion Slip distribution |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《地球物理学报》浏览原始摘要信息 |
| 点击此处可从《地球物理学报》下载免费的PDF全文 |
|
