2018年9月4日伽师5.5级地震序列震源机制解及震源处应力场特征

李艳永; 王成虎; 乌尼尔

doi:10.11899/zzfy20200113

2018年9月4日伽师5.5级地震序列震源机制解及震源处应力场特征

doi: 10.11899/zzfy20200113

1.
新疆维吾尔自治区地震局, 乌鲁木齐 830011
2.
中国地震局地壳应力研究所, 北京 100085

基金项目:

新疆维吾尔自治区自然科学基金 2016D01A061

详细信息

作者简介:
李艳永, 男, 生于1984年。高级工程师。主要从事地震监测工作。E-mail:370451652@qq.com

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出版历程
- 收稿日期: 2019-06-17
- 刊出日期: 2020-03-01

Focal Mechanism Solution for Jiashi M_s5.5 Earthquake Sequence on September 4, 2018 and the Characteristics of Stress Field in the Source Area

1.
Earthquake Agency of Xinjiang Uygur Autonomous Region, Urumqi 830011, China
2.
The Institute of Crustal Dynamics, CEA, Beijing 100085, China

摘要

摘要: 本文采用新疆测震台网数字波形记录，利用CAP和P、S波初动和振幅比方法计算2018年9月4日伽师5.5级地震序列中M_S≥2.5地震的震源机制解，结合地震烈度等震线和双差重定位后的地震序列空间展布等特征分析了此次地震的发震构造，反演了震源处应力场。结果表明，伽师5.5级地震呈NE向的节面I为发震断层面，属于左旋走滑断层，震源深度为9km，发震构造可能为浅部超基底断裂；地震序列中有21次为走滑型，4次为正断型，说明绝大多数序列的破裂方式与主震相近，表明余震应力场主要受主震震源应力场控制；P轴方位在NNE向有明显的优势分布且倾伏角较小，T轴方位在NWW向有明显的优势分布且倾伏角较小，说明震源处主要以NNE向水平挤压和NWW向水平拉张作用为主；此次伽师5.5级地震序列表现的浅部应力场与已有研究得出的震源区深部应力场基本一致，应力形因子R的最优解为0.17，说明震源处近NE向中间主应力σ₂有一定挤压成分。
- 伽师5.5级地震 /
- 震源机制解 /
- 应力场 /
- CAP /
- 初动 /
- 振幅比 /
- 双差定位
Abstract: Based on the digital waveforms record of Xinjiang seismic network,the CAP and P-wave,S-wave initial motion and amplitude ratio methods were used to calculate the focal mechanism solution of the M_S≥2.5 earthquake sequence of Jiashi Ms5.5 earthquake on September 4,2018. The seismogenic structure of this earthquake was analyzed based on the seismic intensity isoseismic lines and the spatial distribution of the earthquake sequence after double differential relocation,and the stress field in the source area was inverted. The results show that the nodal plane I is the seismogenic fault,which is northeast trend and nearly upright left-lateral strike slip fault. The focal depth of main shock is about 9km. It is preliminarily inferred that the seismogenic structure may be superficial ultra crystalline basement fault. The 21 earthquake sequences are strike-slip and 4 earthquake sequences are normal faults. The rupture pattern of most earthquake sequences is similar to that of the main shock,indicating that the aftershock stress field is mainly controlled by the main shock source area stress field. P axis is near north-northeast,and the inclination angle is small. T axis is near northwest-west,and the inclination angle is small. It indicates that the stress field of source area is mainly under action of north-northeast horizontal compression and the northwest-west horizontal tensional. The shallow stress field shown in Jiashi 5.5 earthquake sequences is basically the same as the deep stress field obtained from previous research. The stress shape ratio is 0.17,and it shows that there is a certain compression of σ₂.
- Jiashi M_S5.5 earthquake /
- Focal mechanism solution /
- Stress field /
- CAP /
- First motion /
- Amplitude ratio /
- Double difference location

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图 1 速度模型

Figure 1. Velocity model

下载: 全尺寸图片幻灯片

图 2 伽师5.5级地震震源机制解反演结果

Figure 2. Focal mechanism solution of Jiashi M_S5.5 earthquake

下载: 全尺寸图片幻灯片

图 3 震相走时曲线和序列重定位后的地震序列空间分布

Figure 3. Travel time curves of seismic phases and spatial distribution of seismic sequences after relocation

下载: 全尺寸图片幻灯片

图 4 伽师5.5级地震序列震源深度分布直方图

Figure 4. Histogram of focal depth of Jiashi M_S5.5 earthquake sequences

下载: 全尺寸图片幻灯片

图 5 伽师5.5级地震和早期24次M_S≥2.5地震序列震源机制解

Figure 5. Focal mechanism solutions of Jiashi M_S5.5 earthquake and the early 24 M_S≥2.5 earthquake sequences

下载: 全尺寸图片幻灯片

图 6 伽师5.5级地震和早期24次M_S≥2.5地震序列震源机制解参数统计

Figure 6. The normalized frequency statistics of Jiashi M_S5.5 earthqueake and the early 24 M_S≥2.5 earthquake sequence

下载: 全尺寸图片幻灯片

图 7 伽师5.5级地震震源处应力反演结果球面投影图

注：图中红色表示σ₁，绿色表示σ₂，蓝色表示σ₃，黑色十字表示最优解，彩色点表示95%的置信区间

Figure 7. Spherical projection of source stress field of Jiashi M_S5.5 earthquake

下载: 全尺寸图片幻灯片

表 1 伽师5.5级地震和早期24次M_S≥2.5地震序列震源机制解

Table 1. Focal mechanism solutions of Jiashi M_S5.5 earthquake and the early 24 M_S≥2.5 earthquake sequences

序号	发震时刻	震中/(°)		震级M_S	节面Ⅰ/(°)			节面Ⅱ/(°)			P轴		T轴		B轴		方法
序号	发震时刻	东经	北纬	震级M_S	走向	倾角	滑动角	走向	倾角	滑动角	方位	倾伏角	方位	倾伏角	方位	倾伏角	方法
1	2018-09-04 05:51:44	77.01	39.49	4.7	38	78	-13	130	77	-167	354	17	84	1	176	72	CAP
2	2018-09-04 05:52:55	77.01	39.51	5.5	49	90	3	319	87	-180	183	2	274	2	49	87	CAP
3	2018-09-04 06:48:26	76.99	39.51	3.3	9	58	85	327	80	175	192	3	283	9	83	80	Snoke
4	2018-09-04 06:52:58	77.00	39.51	3.3	43	51	-42	163	58	-132	17	54	282	4	189	35	Snoke
5	2018-09-04 07:10:15	77.04	39.50	2.6	57	90	20	327	70	180	190	14	284	14	57	70	Snoke
6	2018-09-04 07:20:38	77.03	39.51	3.2	63	64	16	326	75	153	16	7	282	28	120	60	Snoke
7	2018-09-04 08:25:24	77.02	39.50	3.8	37	70	-20	134	71	-158	355	28	265	1	173	62	CAP
8	2018-09-04 09:31:35	77.02	39.52	2.7	43	90	35	313	55	180	173	23	274	23	43	55	Snoke
9	2018-09-04 10:51:24	76.96	39.47	4.6	49	84	-2	139	88	-174	4	6	274	3	158	84	CAP
10	2018-09-04 11:26:17	76.99	39.50	3.1	50	86	39	318	50	175	177	24	282	29	54	50	Snoke
11	2018-09-04 15:11:54	76.98	39.50	3.0	51	85	29	318	60	174	181	16	278	24	60	60	Snoke
12	2018-09-04 16:12:20	77.02	39.53	2.6	44	70	2	314	88	160	1	12	267	15	129	70	Snoke
13	2018-09-04 21:11:44	77.01	39.53	3.2	255	40	-82	65	50	-96	295	82	160	5	70	5	Snoke
14	2018-09-04 21:57:57	76.98	39.49	3.4	57	90	20	327	70	180	190	14	284	14	57	70	Snoke
15	2018-09-05 01:10:41	77.03	39.51	2.6	51	85	29	318	60	174	181	16	278	24	60	60	Snoke
16	2018-09-05 01:52:50	77.01	39.52	3.0	101	85	19	9	70	174	233	10	326	17	115	70	Snoke
17	2018-09-05 02:44:08	76.97	39.49	3.6	38	81	-23	131	67	-170	352	22	87	9	197	65	CAP
18	2018-09-05 11:15:21	77.02	39.51	3.7	39	90	-15	129	75	180	353	10	85	10	219	75	CAP
19	2018-09-07 02:05:42	77.01	39.51	2.6	34	50	-83	204	40	-97	344	82	119	5	209	5	Snoke
20	2018-09-07 02:42:45	77.03	39.51	3.3	234	83	-39	329	50	-171	184	31	288	21	46	50	Snoke
21	2018-09-07 04:06:42	77.04	39.51	3.1	62	90	40	332	50	180	190	27	295	27	62	50	Snoke
22	2018-09-07 09:01:23	77.01	39.50	3.0	38	82	-13	130	77	-172	353	14	84	4	189	75	Snoke
23	2018-09-07 17:14:56	77.02	39.52	2.5	34	50	-83	204	40	-97	344	83	119	5	209	5	Snoke
24	2018-09-08 21:49:28	76.99	39.49	2.6	50	90	30	320	60	180	180	20	279	20	50	60	Snoke
25	2018-09-20 13:24:05	76.98	39.50	3.0	70	90	30	340	60	180	200	20	299	20	70	60	Snoke

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表 2 伽师5.5级地震震源处应力反演结果

Table 2. Source stress field of Jiashi M_S5.5 earthquake

σ₁		σ₂		σ₃		应力形因子	应力结构
方位/(°)	倾角/(°)	方位/(°)	倾角/(°)	方位/(°)	倾角/(°)	R	应力结构
-163 -320— -218	24 -63—86	40 12—201	64 -23—88	-69 -80— -60	9 1—20	0.17 0.01—0.45	走滑
注：表中数值范围为各参数95%置信度的不确定性范围

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参考文献(29)

刁桂苓, 王海涛, 高国英等, 2005.伽师强震系列应力场的转向过程.地球物理学报, 48(5):1062-1068. doi: 10.3321/j.issn:0001-5733.2005.05.012

高国英, 聂晓红, 夏爱国, 2004.2003年伽师6.8级地震序列特征和震源机制的初步研究.中国地震, 20(2):179-186. doi: 10.3969/j.issn.1001-4683.2004.02.008

高国英, 王海涛, 温和平等, 2001.帕米尔东北侧中强地震前应力场动态变化特征分析.西北地震学报, 23(4):389-394. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xbdzxb200104012

李艳永, 王成虎, 杨佳佳, 2018.呼图壁地区震源机制解及构造应力场特征分析.大地测量与地球动力学, 38(12):1246-1250. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dkxbydz201812007

刘启元, 陈九辉, 李顺成等, 2000.新疆伽师强震群区三维地壳上地幔S波速度结构及其地震成因的探讨.地球物理学报, 43(3):356-365, 433. doi: 10.3321/j.issn:0001-5733.2000.03.009

龙海英, 高国英, 聂晓红, 2007.1997-1998年伽师强震群震源区应力场特征.西北地震学报, 29(2):145-149. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xbdzxb200702010

单新建, 何玉梅, 朱燕等, 2002.伽师强震群震源破裂特征的初步分析.地球物理学报, 45(3):416-425. doi: 10.3321/j.issn:0001-5733.2002.03.013

苏廼秦, 2003.新疆伽师强震群强震主破裂面走向初探.西北地震学报, 25(3):269-274. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xbdzxb200303014

屠泓为, 万秀红, 高歌等, 2008.1977年至2006年新疆伽师地震断层性质及应力场变化原因初探.地球物理学进展, 23(4):1038-1044. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dqwlxjz200804007

万永革, 2008.美国Landers地震和Hector Mine地震前震源机制与主震机制一致现象的研究.中国地震, 24(3):216-225. doi: 10.3969/j.issn.1001-4683.2008.03.003

万永革, 2019.同一地震多个震源机制中心解的确定.地球物理学报, 62(12):4718-4728. doi: 10.6038/cjg2019M0553

王晓楠, 唐方头, 邵翠茹, 2018.南迦巴瓦构造结周边地区主要断裂现今运动特征.震灾防御技术, 13(2):267-275. http://zzfy.eq-j.cn/zzfyjs/ch/reader/view_abstract.aspx?flag=1&file_no=20180202&journal_id=zzfyjs

王筱荣, 孙甲宁, 王季达, 2005.1997-2004年伽师地区6级地震序列特征研究.内陆地震, 19(1):44-52. doi: 10.3969/j.issn.1001-8956.2005.01.007

徐朝繁, 段永红, 田晓峰等, 2007.新疆伽师强震群区基底界面结构特征.地震学报, 29(5):477-482. doi: 10.3321/j.issn:0253-3782.2007.05.004

张志斌, 金花, 朱皓清, 2019a.2018年9月4日伽师MS 5.5地震与97年及03年伽师强震属于同一发震构造吗?.地球物理学进展, 34(6):2232-2238.

张志斌, 冉慧敏, 金花, 2019b.2016年12月8日新疆呼图壁M_S6.2地震发震构造初步研究.地震工程学报, 41(4):962-969. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xbdzxb201904020

赵翠萍, 陈章立, 郑斯华等, 2008.伽师震源区中等强度地震矩张量反演及其应力场特征.地球物理学报, 51(3):782-792. doi: 10.3321/j.issn:0001-5733.2008.03.019

周仕勇, 许忠淮, 陈晓非, 2001.伽师强震群震源特征及震源机制力学成因分析.地球物理学报, 44(3):654-662. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dqwlxb200105009

周仕勇, 许忠淮, 韩京等, 1999.主地震定位法分析以及1997年新疆伽师强震群高精度定位.地震学报, 21(3):258-265. doi: 10.3321/j.issn:0253-3782.1999.03.005

Efron B. R., Tibshirani, 1986. Bootstrap methods for standard errors, confidence intervals, and other measures of statistical accuracy. Stat. Sci, 1(1):54-75. http://doi.ieeecomputersociety.org/resolve?ref_id=doi:10.1214/ss/1177013815&rfr_id=trans/tk/2010/04/ttk2010040565.htm

Hardebeck J. L., Michael A. J., 2006. Damped regional-scale stress inversions:Methodology and examples for southern California and the Coalinga aftershock sequence. Journal of Geophysical Research:Solid Earth, 111 (B11):B11310.

Kagan Y. Y., 1991.3-D rotation of double-couple earthquake source.Geophys J Int, 106 (3):709-716. doi: 10.1111/j.1365-246X.1991.tb06343.x

Kagan Y. Y., 2003. Accuracy of modern global earthquake catalogs. Phys Earth planet Inter, 135 (2-3):173-209. doi: 10.1016/S0031-9201(02)00214-5

Kagan Y. Y., Jackson D. D., 2000. Probabilistic forecasting of earthquakes. Geophys J Int, l43 (2):438-453. doi: 10.1046/j.1365-246X.2000.01267.x

Martínez-Garzón P., Kwiatek G., Ickrath M., et al., 2014. MSATSI:A MATLAB package for stress inversion, combining solid classic methodology, a new simplified user handling, and a visualization tool. Seismological Research Letters, 85 (4):896-904. doi: 10.1785/0220130189

Snoke J. A., Munsey J. W., Teague A. G., et al., 1984. A program for focal mechanism determination by combined use of polarity and SV-P amplitude ratio data. Earthquake Notes, 55 (3):15. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=10.1111/j.1528-1167.2006.00001_8.x

Waldhauser F., Ellsworth W. L., 2000. A double difference earthquake location algorithm:Method and application to the Northern Hayward Faul, Califomia. Bul1. Seism. Soc. Am, 90 (6):1353-1368. doi: 10.1785/0120000006

Zhao L. S., Helmberger D. V., 1994. Source estimation from broadband regional seismograms.Bull Seismol Soc Amer, 84 (1):91-104.

Zhu L. P., Helmberger D. V., 1996. Advancement in source estimation techniques using broadband regional seismograms. Bull Seismol Soc Amer, 86 (5):1634-l641.

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