地震研究

利用云南省地震台网的宽频带数据,采用CAP方法计算了2013年3月3日洱源M_S5.5地震前后共10次M_L≥3.4地震的震源机制解,分析了洱源M_S5.5地震前后震源机制解的一致性变化特征,结合精定位结果、震后现场灾害评估报告及震区地质构造情况,判定维西—巍山断裂以西的苍山西麓炼铁盆地东缘主边界断裂带为洱源M_S5.5地震的发震构造,震源机制解节面Ⅱ(走向160°、倾角48°、滑动解-99°)为其发震断层面。

Using the broadband data recorded by Yunnan Seismic Network,we calculated the focal mechanism solutions of 10 M_L≥3.4 earthquakes before and after Eryuan M_S5.5 earthquake on Mar.3,2013 by CAP(cut and paste)algorithm,and analyzed the consistency viaration characteristics of the focal mechanism solutions of the study earthquakes. Combined with the precision positioning results,the site disaster assessment report after the earthquake and the geological structure in seismic area,we concluded that the seismogenic structure of Eryuan M_S5.5 earthquake was the main boundary fault zone of the east boundary of the Liantie basin in the west of Cangshan to the west of the Weixi-Weishan Fault. The focal mechanism solution of the nodal surface Ⅱ,whose strike is 160°,the dip is 48° and the slip is -99° is the seismogenic fault plane.

引言
1 地震概况
2 CAP计算方法及资料计算
3 反演结果及分析
4 结论与讨论

图1 洱源地震序列M-T图<br/>Fig.1 The M-T diagram of the Eryuan MS5.5 earthquake sequence

图1 洱源地震序列M-T图
Fig.1 The M-T diagram of the Eryuan MS5.5 earthquake sequence

表1 2013年3月3日洱源MS5.5主震及其发生前后9次ML≥3.4地震事件震源机解结果<br/>Tab.1 Focal mechanism solution results of Eryuan MS5.5 main shock on Mar.3,2013 and 9 ML≥3.4 earthquakes before cmd after the main shock

表1 2013年3月3日洱源MS5.5主震及其发生前后9次ML≥3.4地震事件震源机解结果
Tab.1 Focal mechanism solution results of Eryuan MS5.5 main shock on Mar.3,2013 and 9 ML≥3.4 earthquakes before cmd after the main shock

表2 采用的速度模型<br/>Tab.2 Velocity model using for inversion

表2 采用的速度模型
Tab.2 Velocity model using for inversion

图2 洱源MS5.5主震的震源机制解及部分台站波形拟合图<br/>Fig.2 Focal mechanism solution of the Eryuan MS5.5 mainshock and waveforms fitting diagrams of some stations

图2 洱源MS5.5主震的震源机制解及部分台站波形拟合图
Fig.2 Focal mechanism solution of the Eryuan MS5.5 mainshock and waveforms fitting diagrams of some stations

表3 本文与其它研究机构震源机制解的比较<br/>Tab.3 Comparison of focal mechanism solutions of Eryuan MS5.5 main shock obtained by different organizations and in this paper

表3 本文与其它研究机构震源机制解的比较
Tab.3 Comparison of focal mechanism solutions of Eryuan MS5.5 main shock obtained by different organizations and in this paper

图3 洱源MS5.5地震震源机制解反演误差—深度分布<br/>Fig.3 Error and depth distribution inversed by focal mechanism solutions of Eryuan MS5.5 earthquake

图3 洱源MS5.5地震震源机制解反演误差—深度分布
Fig.3 Error and depth distribution inversed by focal mechanism solutions of Eryuan MS5.5 earthquake

图4 10次ML≥3.4地震的震中位置及震源机制解结果<br/>Fig.4 Epicenter location and distribution of focal mechanism solutions of 10 ML≥3.4 earthquakes

图4 10次ML≥3.4地震的震中位置及震源机制解结果
Fig.4 Epicenter location and distribution of focal mechanism solutions of 10 ML≥3.4 earthquakes

图5 洱源MS5.5地震前后10次ML≥3.4地震事件(序号同表1)滑动角随时间变化情况<br/>Fig.5 Slide angle solutions of 10 ML≥3.4 earthquakes(the serial number is the same as in Tab.1)before and after the Eryuan MS5.5 earthquake changed with time

图5 洱源MS5.5地震前后10次ML≥3.4地震事件(序号同表1)滑动角随时间变化情况
Fig.5 Slide angle solutions of 10 ML≥3.4 earthquakes(the serial number is the same as in Tab.1)before and after the Eryuan MS5.5 earthquake changed with time

图6 历史中强地震震源机制解分布图<br/>Fig.6 Distribution of focal mechanism solutions of the moderate strong earthquakes in the history

图6 历史中强地震震源机制解分布图
Fig.6 Distribution of focal mechanism solutions of the moderate strong earthquakes in the history

图7 洱源MS5.5地震后19小时地震精定位结果<br/>Fig.7 The precision positioning results of earthquakes occurred in 19 hours after Eryuan MS5.5 earthquake

图7 洱源MS5.5地震后19小时地震精定位结果
Fig.7 The precision positioning results of earthquakes occurred in 19 hours after Eryuan MS5.5 earthquake

曹颖,吴小平,沈娅宏,等.2013.由震源机制解资料研究川滇地区构造应力场[J].地震研究,36(2):165-172.
地质力学研究所.2013.地质力学研究所完成云南洱源5.5级地震的地震地质野外科学考察工作[EB/OL].(2013-03-20)[2014-07-24]http://www.geomech.ac.cn/xinwen/2013/ 2013031902.htm.
胡鸿翔,陆涵行,王椿镛,等.1986.滇西地区地壳结构的爆破地震研究[J].地球物理学报,29(2):133-143.
胡家富,苏有锦,朱雄关,等.2003.云南的地壳S波速度与波速比结构及其意义[J].中国科学(D辑),33(8):714-722.
虎雄林,解朝娣,刘丽芳,等.2013.2003年大姚6.2、6.3级地震构造应力环境及静态应力触发研究[J].地震研究,36(1):47-56.
林中洋,胡鸿翔,张文彬,等.1993.滇西地区地壳上地幔速度结构特征的研究[J].地震学报,15(4):427-440.
龙锋,张永久,闻学泽,等.2010.2008年8月30日攀枝花—会理6.1级地震序列序列M≥4.0事件的震源机制解[J].地球物理学报,53(12):2852-2860.
龙海英,高国英,聂晓红,等.2007.乌鲁木齐地区中小地震震源机制解及构造应力场[J].地震,27(3):89-96.
吕坚,郑秀芬,肖健,等.2013.2012年9月7日云南彝良MS5.7、MS5.6地震震源破裂特征与发震构造研究[J].地球物理学报,56(8):2645-2654.
吕坚,郑勇,倪四道,等.2008.2005年11月26日九江—瑞昌MS5.7、MS4.8地震的震源机制解与发震构造研究[J].地球物理学报,51(1):158-164.
王椿镛,Mooney W.D.,王溪莉,等.2002.川滇地区地壳上地幔三维速度结构研究[J].地震学报,25(1):1-15.
吴开统,焦远碧,吕培苓,等.1990.地震序列概论[M].北京:北京大学出版社.
杨国华,王琪,王敏,等.2003.云南地区现今地壳水平运动与变形特征[J].大地测量与地球动力学,23(2):7-14.
张建国,谢英情,金明培,等.2009.中越红河断裂活动性研究[M].昆明:云南科技出版社.
张中杰,白志明,王椿镛,等.2005.三江地区地壳结构及动力学意义:去过遮放—宾川地震反射/折射剖面的启示[J].中国科学(D辑),35(4):314-319.
赵小艳,苏有锦,付虹,等.2009.用P波、S波初动和振幅比计算中小地震震源机制在云南地区的应用[J].内陆地震,23(3):394-402.
郑勇,马宏生,吕坚,等.2009.汶川地震强余震(MS≥5.6)的震源机制解及其与发震构造的关系[J].中国科学,39(4):413-426.
中国地震局地球物理研究所,“中国地震科学台阵探测项目—南北地震带南段”项目组.2013.“中国地震台阵探测”项目快报——2013年3月3日云南大理白族自治州洱源县5.5级地震[EB/OL].(2013-03-03)[2014-07-24]http://www.cea-igp.ac.cn/upload/Image/mrtp/tpxw/2012n12r/2664019747.jpg.
Zhao L.S.,Helmgerger D.V..1994.Source Estimation from Broad Band Regional Seismogram[J].Bull.Seism.Soc.Am.,84(1):91-104.
Zhu L.P.,Helmgerger D.V..1996.Advancement in Source Estimation Techniques using Broadband Regional Seismogram[J].Bull. Seism. Soc.Am.,86(5):1634-1641.

备注

引言

1 地震概况

2 CAP计算方法及资料计算

3 反演结果及分析

4 结论与讨论

期刊信息