Yabuki&Matsu’ura方法在汶川MW7.9地震反演中的应用

地震 ›› 2012, Vol. 32 ›› Issue (2): 121-128.

Yabuki&Matsu’ura方法在汶川M_W7.9地震反演中的应用

王阅兵, 金红林, 付广裕

中国地震局地震预测研究所, 北京 100036

收稿日期:2012-02-10 修回日期:2012-03-27 出版日期:2012-04-30 发布日期:2021-08-20
作者简介:王阅兵(1985-), 男, 湖北钟祥人, 在读硕士研究生, 主要从事地形变数据反演等研究。
基金资助:
国际科技合作项目(2010DFB20190)

Application of Yabuki&Matsu’ura’s Inversion Method to the 2008 Wenchuan M_W7.9 Earthquake

WANG Yue-bing, JIN Hong-lin, FU Guang-yu

Institute of Earthquake Science, CEA, Beijing 100036, China

Received:2012-02-10 Revised:2012-03-27 Online:2012-04-30 Published:2021-08-20

摘要/Abstract

摘要： 2008年5月12日, 青藏高原东缘龙门山断裂带发生汶川M_W7.9地震, 该地震使得北川—映秀断裂、灌县—江油断裂发生了同震破裂。本文主要利用震后通过复测获得的GPS同震形变场, 采用Yabuki&Matsu’ura反演计算方法和分段平面断层模型, 反演了地震同震滑动分布。结果表明: 映秀—北川主破裂带的断层错动, 在映秀附近以逆冲滑动为主, 而在北川以北, 其走滑运动明显大于逆冲, 这一结果与震后地质调查结果与通过地震波研究获得的断层破裂特征相一致; 反演得到的最大滑动量达到9.3 m和9.6 m, 分别对应于这次地震中地表破坏最为严重的北川和映秀地区; 由所获得的滑动分布计算的地震矩为8.07×10²⁰ N·m, 对应的震级为M_W7.9。研究结果初步显示, Yabuki&Matsu’ura反演方法可适用在内陆地震断层反演计算中。

关键词: 汶川地震, GPS同震形变场, Yabuki&Mattsu'ura反演方法, 分段平面断层模型

Abstract: On May 12, 2008, the great Wenchuan earthquake occurred on the Longmenshan belt, which is located at the eastern margin of the Tibetan Plateau, rupturing the Beichuan-Yingxiu and Guanxian-Jiangyou faults. We apply Yabuki&Matsu’ura’s inversion method to estimate the co-seismic slip distribution of thhis earthquake from GPS data. The whole fault model is divided into four sub-faults during our inversion. Our results show that the slips caused by the great earthquake are characterized mainly by thrust motion near Yingxiu, the south segment of the Yingxiu-Beichuan fault; the dextral components are apparently larger than thrust slips at the north segment of the fault. Our estimations agree well with the results of geologic survey and the characteristics of rupturing. The estimated slips have two high-slip concentrations up to 9.6 m and 9.3 m, located respectively near the Yingxiu town and Beichuan city, which suffered the greatest fatalities and structure damages during the earthquake. The total moment released by the great earthquake is about 8.07×10²⁰ N·m, corresponding to an earthquake with magnitude of M_W7.9. Our study shows that Yabuki&Matsu’ura’s inversion method is suitable to estimate the fault slip model in mainland China.

Key words: Yabuki&Matsu’ura’s inversion method, GPS data;Wenchuan earthquake, Planar fault segments

中图分类号:

P315.7

王阅兵, 金红林, 付广裕. Yabuki&Matsu’ura方法在汶川M_W7.9地震反演中的应用[J]. 地震, 2012, 32(2): 121-128.

WANG Yue-bing, JIN Hong-lin, FU Guang-yu. Application of Yabuki&Matsu’ura’s Inversion Method to the 2008 Wenchuan M_W7.9 Earthquake[J]. EARTHQUAKE, 2012, 32(2): 121-128.

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