Determination of the focal mechanism solutions of the earthquakes with MS≥4.0 occurred in the mainland of China during February to March 2022
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摘要: 本文利用中国地震台网记录的宽频带波形资料,采用近震全波形反演方法得到2022年2月1日—3月31日发生在中国大陆地区的MS≥4.0共20次地震的震源机制解。结果显示逆断型5次,走滑型14次,未知型1次。Abstract: In this paper, the regional full waveform inversion of the broadband waveforms from China Seismic Network are conducted, and the focal mechanism solutions of the 20 earthquakes with MS≥4.0 in the mainland of China from February 1 to March 31, 2022 are obtained. The types of these focal mechanism solutions show 5 reverse faulting, 14 strike-slip faulting and 1 unknown earthquakes.
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Key words:
- focal mechanism /
- source parameters
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图 2 2022年3月26日青海德令哈MS6.0 (MW5.7)地震震源机制解反演
(a)波形相关系数随反演深度分布,彩色条棒表示偏量矩张量反演时双力偶分量所占比例;(b)本文所得震源机制解对应的三分量理论(红色)和实际(黑色)波形对比图。图中右侧字符表示台站代码,波形上方数字为方差减少量值,代表波形拟合程度
Figure 2. Focal mechanism inversion of Qinghai Delingha MS6.0 (MW5.7) earthquake on March 26, 2022
(a) Correlation between observed and synthetic waveforms versus depth, the colored-bar shows double couple percentage using ISOLA in deviatoric mode; (b) Comparison of the three-component theoretical (red) and observational (black) waveforms corresponding to focal mechanism solutions obtained in this paper. The station codes are plotted on the right of figure, the numbers above the waveforms are variance reduction, which indicate the fitting degree of waveform
表 1 2022年2—3月中国大陆地区MS≥4.0地震基本参数
Table 1. Events list of the earthquakes with MS≥4.0 in the mainland of China
序号 发震时刻(BJT) 北纬
/°东经
/°深度
/km震级(MS) 参考地名 1 2022-02-01 06:01:28.5 31.91 104.27 10 4.0 四川绵阳市北川县 2 2022-02-02 07:13:09.4 33.20 95.05 11 4.1 青海玉树州杂多县 3 2022-02-10 04:11:29.2 35.56 88.07 17 4.0 西藏那曲市双湖县 4 2022-02-10 15:36:38.0 25.56 100.04 12 4.1 云南大理州大理市 5 2022-02-18 05:12:15.6 38.68 90.69 10 4.3 新疆巴音郭楞州若羌县 6 2022-02-22 10:40:14.3 40.99 83.13 12 4.1 新疆阿克苏地区沙雅县 7 2022-02-28 03:52:16.9 41.87 88.12 10 4.6 新疆巴音郭楞州和硕县 8 2022-03-01 03:54:11.5 39.37 79.24 10 4.3 新疆喀什地区巴楚县 9 2022-03-02 08:18:45.5 35.74 95.87 9 4.8 青海海西州都兰县 10 2022-03-05 22:43:03.1 22.34 101.65 6 4.5 云南普洱市江城县 11 2022-03-07 22:35:25.7 37.73 101.44 9 4.2 青海海北州门源县 12 2022-03-14 02:28:48.6 22.51 115.04 25 4.1 广东惠州市惠东县海域 13 2022-03-16 02:44:35.2 45.25 124.75 10 4.3 吉林松原市宁江区 14 2022-03-17 08:26:03.0 39.02 97.66 9 5.1 甘肃张掖市肃南县 15 2022-03-17 21:41:18.5 36.10 77.86 10 5.2 新疆和田地区皮山县 16 2022-03-26 00:21:02.2 38.50 97.33 10 6.0 青海海西州德令哈市 17 2022-03-26 00:28:40.5 38.47 97.34 10 4.3 青海海西州德令哈市 18 2022-03-26 01:05:08.1 38.51 97.34 10 4.1 青海海西州德令哈市 19 2022-03-26 02:50:03.7 38.47 97.37 10 4.9 青海海西州德令哈市 20 2022-03-29 05:25:09.4 30.03 103.41 10 4.3 四川眉山市丹棱县 表 2 2022年2—3月中国大陆地区MS≥4.0地震的震源机制结果
Table 2. Focal mechanisms of the earthquakes with MS≥4.0 in the mainland of China
序号 发震时刻(BJT) 节面Ⅰ 节面Ⅱ P 轴 T 轴 矩心
深度
/km矩震级 (MW) VR CN 图示 走向
/°倾角
/°滑动角
/°走向
/°倾角
/°滑动角
/°方位角
/°仰角
/°方位角
/°仰角
/°1 2022-02-01
06:01:28.5115 58 91 293 32 88 204 13 29 77 19 4.1 0.79 2.0 2 2022-02-02
07:13:09.476 43 −10 174 83 −133 47 37 296 26 5 4.3 0.72 3.7 3 2022-02-10
04:11:29.2332 86 174 53 84 4 8 2 277 7 7 4.4 0.72 2.6 4 2022-02-10
15:36:38.0143 71 −165 48 76 −19 5 23 97 3 8 4.2 0.77 1.9 5 2022-02-18
05:12:15.686 52 102 247 39 75 168 7 43 78 5 4.5 0.56 4.7 6 2022-02-22
10:40:14.3283 73 17 188 74 163 236 0 146 24 6 4.2 0.59 1.6 7 2022-02-28
03:52:16.9166 59 92 341 31 86 254 14 82 76 15 4.3 0.65 2.7 8 2022-03-01
03:54:11.560 60 37 310 59 144 185 1 276 46 16 4.1 0.54 2.3 9 2022-03-02
08:18:45.5270 57 −27 15 68 −144 236 41 140 7 6 4.9 0.78 2.8 10 2022-03-05
22:43:03.1321 84 176 51 86 6 186 1 276 7 6 4.5 0.95 2.5 11 2022-03-07
22:35:25.7222 48 174 316 85 42 82 24 188 32 4 4.5 0.72 5.6 12 2022-03-14
02:28:48.658 84 −169 327 79 −6 283 12 192 3 21 4.0 0.76 2.2 13 2022-03-16
02:44:35.2212 74 171 305 81 16 78 5 170 18 7 4.2 0.73 3.1 14 2022-03-17
08:26:03.0346 81 168 78 79 9 32 2 302 15 9 4.8 0.75 2.7 15 2022-03-17
21:41:18.5109 68 66 338 32 135 216 20 344 60 6 5.0 0.80 4.2 16 2022-03-26
00:21:02.2175 77 −162 80 72 −13 38 22 307 3 9 5.7 0.81 2.5 17 2022-03-26
00:28:40.584 68 −33 187 60 −154 43 39 137 5 8 4.7 0.64 3.1 18 2022-03-26
01:05:08.1172 70 −170 78 81 −21 33 21 126 8 10 4.5 0.70 1.8 19 2022-03-26
02:50:03.785 52 −9 180 83 −141 50 32 307 21 8 4.7 0.70 5.9 20 2022-03-29
05:25:09.4201 74 165 295 76 16 68 1 158 21 4 4.2 0.89 2.2 -
[1] 梁姗姗,邹立晔,刘艳琼,等. 2021年12月中国大陆地区M≥4.0地震震源机制解测定[J]. 地震科学进展,2022,52(1):40-44Liang S S,Zou L Y,Liu Y Q,et al. Determination the focal mechanism solutions of earthquakes with M≥4.0 occurred in the mainland of China in December 2021[J]. Progress in Earthquake Sciences,2022,52(1):40-44 [2] 梁姗姗,邹立晔,刘艳琼,等. 2022 年 1 月中国大陆地区 MS≥4.0 地震震源机制解测定[J]. 地震科学进展,2022,52(2):89-94Liang S S,Zou L Y,Liu Y Q,et al. Determination of the focal mechanism solutions of the earthquakes with MS≥4.0 occurred in the mainland of China in January 2022[J]. Progress in Earthquake Sciences,2022,52(2):89-94 [3] Sokos E N,Zahradnik J. ISOLA a Fortran code and a Matlab GUI to perform multiple-point source inversion of seismic data[J]. Computers and Geosciences,2008,34(8):967-977 doi: 10.1016/j.cageo.2007.07.005 [4] Sokos E,Zahradnik J. Evaluating centroid-moment-tensor uncertainty in the new version of ISOLA software[J]. Seismological Research Letters,2013,84(4):656-665 doi: 10.1785/0220130002 [5] Bassin C G L,Laske G,Masters G. The current limits of resolution for surface wave tomography in North America[J]. Eos Transactions American Geophysical Union,2000,81(48):F897 [6] Kennett B L N,Kerry N J. Seismic waves in a stratified half space[J]. Geophysical Journal International,1979,57(3):557-583 doi: 10.1111/j.1365-246X.1979.tb06779.x [7] Bouchon M. A simple method to calculate Green’s functions for elastic layered media[J]. Bulletin of the Seismological Society of America,1981,71(4):959-971 doi: 10.1785/BSSA0710040959 -