2020年1月19日新疆伽师M6.4地震的重定位及震源机制

doi:10.3969/j.issn.0253-4967.2021.02.006

地震地质 ›› 2021, Vol. 43 ›› Issue (2): 345-356.DOI: 10.3969/j.issn.0253-4967.2021.02.006

2020年1月19日新疆伽师M6.4地震的重定位及震源机制

郭志¹⁾, 高星²⁾, 路珍³⁾

1)中国地震局地质研究所地震动力学国家重点实验室, 新疆帕米尔陆内俯冲国家野外科学观测研究站, 北京 100029;
2)中国科学院地理科学与资源研究所, 资源与环境信息系统国家重点实验室, 北京 100101;
3)中国地震局第二监测中心, 西安 710054

收稿日期:2020-09-21 修回日期:2021-02-20 出版日期:2021-04-20 发布日期:2021-07-19
作者简介:郭志, 男, 1977年生, 2010年于中国科学院青藏高原研究所获构造地质学博士学位, 副研究员, 从事地震震源机制及地壳结构研究, 电话: 010-62009161, E-mail: guozhi@ies.ac.cn。
基金资助:
中国地震局地质研究所基本科研业务专项(IGCEA2001, IGCEA1708)和国家自然科学基金(41774050, 41574036)共同资助

RELOCATION AND FOCAL MECHANISM FOR THE XINJIANG JIASHI EARTHQUAKE ON 19 JANUARY, 2020

GUO Zhi¹⁾, GAO Xing²⁾, LU Zhen³⁾

1)State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Xinjiang Pamir Intracontinental Subduction National Field Observation and Research Station, Beijing 100029, China;
2)State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China;
3)The Second Monitoring and Application Center, China Earthquake Administration, Xi'an 710054, China

Received:2020-09-21 Revised:2021-02-20 Online:2021-04-20 Published:2021-07-19

摘要/Abstract

摘要： 采用双差重定位和W震相反演方法分析”地震编目系统”和中国地震台网中心提供的地震观测报告及区域地震波形数据,对2020年1月19日新疆伽师地震进行重定位,反演前震及主震震源机制。地震序列重定位结果显示,2020伽师地震呈两个优势方向展布,分别为WNW向和NNW向;其中WNW向为主要余震优势分布区域,呈现长约34km条带状分布在柯坪塔格断裂带西段的北侧。另外一条优势分布沿NNW向长约8km。深度剖面显示,震源深度集中分布于10~20km范围。震源机制反演结果表明,2020年1月19日新疆伽师M_S6.4主震2个发震断层面参数分别为:节面Ⅰ,走向76°,倾角81°,滑动角109°;节面Ⅱ,走向190°,倾角21°,滑动角26°,矩震级M_W5.87,震源表现为逆断为主外加少量走滑的地震破裂事件。综合分析伽师地震序列的重定位、震源机制和震中及附近区域的地质构造背景,推断2020新疆伽师地震的发震破裂面呈WNW走向,发震断层为近EW走向柯坪塔格断裂带的西段。

关键词: 2020年伽师地震, 双差重定位, W震相, 矩张量反演

Abstract: As the most active and spectacular intracontinental mountain ranges in Central Asia, Tian Shan is a natural laboratory to explore and understand the geodynamic processes involved in intracontinental mountain building. The origin of Tian Shan can be traced back to the collision and accretion of several micro-continents, island arcs, and accretionary prisms initiated in the Paleozoic. This tectonic activity continued into the Mesozoic. From the Cretaceous to the early Tertiary, the mountain ranges were eroded and reduced to a flat plain. Then, in the later Tertiary, uplift was rejuvenated as a far-field consequence of the India-Eurasia collision, and continues to present day, characterized by the active seismicity in Tienshan in modern times. The geology of present-day central Tian Shan is mainly composed of intermontane basins and subparallel ranges, separated by the east-west striking Cenozoic active thrust faults stretching approximately 2 500km in length. On the southern and northern margins of the Tian Shan Range, the Tarim Basin and the Kazakh Shield act as stable blocks. Situated in the southwest foreland of Tien Shan, the Kashgar region is a seismic active area since the 20^th century, several strong earthquakes stroke the region and the surround areas, causing severe damage to the local residents. In this study, we apply the double-difference relocation technique and W-phase method to relocate the 19 January, 2020 Xinjiang Jiashi earthquake, and to determine the focal mechanisms using data provided by China Earthquake Networks Center. The relocated epicenters of the 2020 Jiashi earthquake sequence show two dominant spatial distribution directions. The major NWW-trending spatial distribution shows a Kepingtage Fault-paralleled narrow belt stretching about 34km, with most of aftershocks distributed in the northern side of the fault. The secondary spatial distribution shows a NNW-striking belt stretching about 8km. The depth profiles show a predominant epicentral depth at the range of 10~20km. The focal parameters for the 19 January, 2020 Xinjiang Jiashi M6.4 earthquake are: strike 76°, dip 81°, rake 109° for the nodal plane Ⅰ, and strike 190°, dip 21°, rake 26° for nodal plane Ⅱ, and the moment magnitude is M_W5.87. The focal parameters indicate that the earthquake event is characterized by dominant thrust with minor strike movement. Combined with the analysis of the relocated epicentral locations, focal mechanisms and geological settings, it is inferred that the seismogenic fault of the 19 January 2020 Jiashi M6.4 earthquake is the west segment of the near E-W trending Kepingtage thrust fault.

Key words: the 2020 Jiashi earthquake, double-difference relocation, W-phase, moment tensor inversion

中图分类号:

P315.3+3

郭志, 高星, 路珍. 2020年1月19日新疆伽师M6.4地震的重定位及震源机制[J]. 地震地质, 2021, 43(2): 345-356.

GUO Zhi, GAO Xing, LU Zhen. RELOCATION AND FOCAL MECHANISM FOR THE XINJIANG JIASHI EARTHQUAKE ON 19 JANUARY, 2020[J]. SEISMOLOGY AND GEOLOGY, 2021, 43(2): 345-356.

参考文献

[1] 邓起东, 张培震, 冉勇康, 等. 2002. 中国活动构造基本特征[J]. 中国科学(D辑), 32(12): 1020—1030.
DENG Qi-dong, ZHANG Pei-zhen, RAN Yong-kang, et al. 2003. Basic characterics of active tectonics of China[J]. Science in China(Ser D), 46(4): 356—372.
[2] 国家测震台网数据备份中心. 2017. 国家测震台网地震波形数据[DB/OL]. 中国地震局地球物理研究所. http://www.seisdmc.ac.cn. doi: 10.11998/SeisDmc/SN.
Data Management Center of China National Seismic Network. 2017. Waveform data of China National Seismic Network[DB/OL]. Institute of Geophysics, China Earthquake Administration. http://www.seisdmc.ac.cn(in Chinese).
[3] 郭志, 陈立春, 李通, 等. 2018. 2017年8月8日四川九寨沟M7.0和9日新疆精河M6.6地震震源机制解[J]. 地震地质, 40(6): 1294—1304. doi: 10.3969/j.issn.0253-4967.2018.06.
GUO Zhi, CHEN Li-chun, LI Tong, et al. 2018. Focal mechanism of the August 8, M7.0 Sichuan Jiuzhaigou and August 9, M6.6 Xinjiang Jinghe earthquakes of 2017[J]. Seismology and Geology, 40(6): 1294—1304(in Chinese).
[4] 韦伟, 谢超, 周本刚, 等. 2018. 西藏米林M6.9地震及其余震序列地震定位[J]. 科学通报, 63(15): 1493—1501.
WEI Wei, XIE Chao, ZHOU Ben-gang, et al. 2018. Location of the main shock and aftershock sequences of the M6.9 Mainling earthquake, Tibet[J]. Chinese Science Bulletin, 63(15): 1493—1501(in Chinese).
[5] 张广伟, 雷建设, 梁姗姗, 等. 2014. 2014年8月3日云南鲁甸M_S6.5地震序列重定位与震源机制研究[J]. 地球物理学报, 57(9): 3018—3027. doi: 10.6038/cjg20140926.
ZHANG Guang-wei, LEI Jian-she, LIANG Shan-shan, et al. 2014. Relocations and focal mechanism solutions of the 3 August 2014 Ludian, Yunnan M_S6.5 earthquake sequence[J]. Chinese Journal of Geophysics, 57(9): 3018—3027(in Chinese).
[6] 张国民, 汪素云, 李丽, 等. 2002. 中国大陆地震震源深度及其构造含义[J]. 科学通报, 47(9): 663—668.
ZHANG Guo-min, WANG Su-yun, LI Li, et al. 2002. Focal depth research of earthquakes in Mainland China: Implication for tectonics[J]. Chinese Science Bulletin, 47(9): 663—668(in Chinese).
[7] 郑秀芬, 欧阳飚, 张东宁, 等. 2009. “国家测震台网数据备份中心”技术系统建设及其对汶川大地震研究的数据支撑[J]. 地球物理学报, 52(5): 1412—1417. doi: 10.3969/j.issn.0001-5733.2009.05.031.
ZHENG Xiu-fen, OUYANG Biao, ZHANG Dong-ning, et al. 2009. Technical system construction of Data Backup Centre for China Seismograph Network and the data support to researches on the Wenchuan earthquake[J]. Chinese Journal of Geophysics, 52(5): 1412—1417(in Chinese).
[8] Duputel Z, Rivera L, Kanamori H, et al. 2012. W phase source inversion for moderate to large earthquakes(1990—2010)[J]. Geophysical Journal International, 189(2): 1125—1147.
[9] Ekström G, Nettles M, Dziewoński A. 2012. The global CMT project 2004—2010: Centroid-moment tensors for 13017 earthquakes[J]. Physics of the Earth and Planetary Interiors, 200-21:1—9.
[10] Gao X, Guo Z, Wang W, et al. 2014. Crustal structure beneath the central Tien Shan from ambient noise tomography[J]. Terra Nova, 26(6): 469—476.
[11] Hayes G P, Rivera L, Kanamori H. 2009. Source inversion of the W-Phase: Real-time implementation and extension to low magnitudes[J]. Seismological Research Letters, 80(5): 817—822.
[12] Hunter J D. 2007. Matplotlib: A 2D graphics environment[J]. Computing in Science and Engineering, 9(3): 90—95.
[13] Jost M, Herrmann R. 1989. A student’s guide to and review of moment tensors[J]. Seismological Research Letters, 60(2): 37—57.
[14] Kanamori H. 1993. W phase[J]. Geophysical Research Letters, 20(16): 1691—1694.
[15] Kanamori H, Rivera L. 2008. Source inversion of W phase: Speeding up seismic tsunami warning[J]. Geophysical Journal International, 175(1): 222—238.
[16] Knopoff L, Randall M J. 1970. The compensated linear-vector dipole: A possible mechanism for deep earthquakes[J]. Journal of Geophysical Research, 75(26): 4957—4963.
[17] Lei J. 2011. Seismic tomographic imaging of the crust and upper mantle under the central and western Tien Shan orogenic belt[J]. Journal of Geophysical Research: Solid Earth, 116(B9): B09305.
[18] Lei J, Zhao D. 2007. Teleseismic P-wave tomography and the upper mantle structure of the central Tien Shan orogenic belt[J]. Physics of the Earth and Planetary Interiors, 162(3-4): 165—185.
[19] Lü Z, Gao H, Lei J, et al. 2019. Crustal and upper mantle structure of the Tien Shan orogenic belt from full-wave ambient noise tomography[J]. Journal of Geophysical Research: Solid Earth, 124(4): 3987—4000.
[20] Michelini A, Lomax A. 2004. The effect of velocity structure errors on double-difference earthquake location[J]. Geophysical Research Letters, 31(9): 1—4.
[21] Waldhauser F, Ellsworth W L. 2000. A double-difference earthquake location algorithm: Method and application to the northern Hayward Fault, California[J]. Bulletin of the Seismological Society of America, 90(6): 1353—1368.
[22] Wessel P, Smith W H F. 1991. Free software helps map and display data[J]. Eos, Transactions American Geophysical Union, 72(41): 441—446.
[23] Zhao J, Liu G, Lu Z, et al. 2003. Lithospheric structure and dynamic processes of the Tianshan orogenic belt and the Junggar Basin[J]. Tectonophysics, 376(3-4): 199—239.
[24] Zhu L, Helmberger D V. 1996. Advancement in source estimation techniques using broadband regional seismograms[J]. Bulletin of the Seismological Society of America, 86(5): 1634—1641.
[25] Zhu L, Rivera L A. 2002. A note on the dynamic and static displacements from a point source in multilayered media[J]. Geophysical Journal International, 148(3): 619—627.

2020年1月19日新疆伽师M6.4地震的重定位及震源机制

RELOCATION AND FOCAL MECHANISM FOR THE XINJIANG JIASHI EARTHQUAKE ON 19 JANUARY, 2020

RichHTML

PDF (PC)

可视化

摘要/Abstract

引用本文

使用本文

参考文献

相关文章 10

编辑推荐

Metrics

本文评价

[1]	王莹, 赵韬, 胡景, 刘春. 2021年云南漾濞6.4级地震序列重定位及震源机制解特征分析[J]. 地震地质, 2021, 43(4): 847-863.
[2]	赵韬, 王莹, 马冀, 邵若潼, 徐一斐, 胡景. 2021年青海玛多7.4级地震序列重定位和震源机制特征[J]. 地震地质, 2021, 43(4): 790-805.
[3]	姚远, 李涛, 刘奇, 邸宁. 2020年1月19日新疆伽师M_W6.0地震震中区地质灾害特点[J]. 地震地质, 2021, 43(2): 410-429.
[4]	刘旭宙, 沈旭章, 何骁慧, 蒲举. 2019年夏河M5.7地震的余震序列重定位及发震构造[J]. 地震地质, 2021, 43(1): 197-208.
[5]	李通, 郭志, 高星. 云南通海2018年8月地震序列重定位及震源机制[J]. 地震地质, 2020, 42(4): 881-892.
[6]	郭志, 陈立春, 李通, 高星. 2017年8月8日四川九寨沟M7.0和9日新疆精河M6.6地震震源机制解[J]. 地震地质, 2018, 40(6): 1294-1304.
[7]	金春华, 何秋菊, 田小慧. 永宁2次M_S4.5地震震源机制及深度[J]. 地震地质, 2017, 39(1): 193-205.
[8]	吴海波, 姚运生, 申学林, 赵凌云. 2014年秭归M_S4.5和M_S4.9地震震源与发震构造特征[J]. 地震地质, 2015, 37(3): 719-730.
[9]	张丽芬, 姚运生, 廖武林. 2011年M_S4.6瑞昌-阳新地震的震源机制及发震构造探讨[J]. 地震地质, 2013, 35(2): 290-299.
[10]	王卫东, 李少睿. 利用地震矩张量反演阿尔金断裂带现今运动学特征[J]. 地震地质, 1999, 21(2): 171-175.