2012年江苏高邮、宝应交界M_S4.9地震发震断层参数测定
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摘要
基于一维单侧有限移动震源模式,根据地震波传播过程中的多普勒效应,分别利用P波和S波拐角频率的方位变化,反演2012年7月20日江苏高邮、宝应交界MS4.9地震的发震断层面参数。P波和S波拐角频率的反演结果一致显示:本次地震的断层面破裂方向为232°左右,破裂面呈NE-SW向;地震马赫数v/c为0.2左右,平均破裂速度小于S波速度,破裂长度较短,为0.2~0.3km左右。破裂面方位与震源机制解、宏观烈度调查和余震精定位的研究结果具有一致性,结合震区周边的地质构造背景,分析认为滁河断裂很可能是高邮、宝应交界MS4.9地震的发震构造。
Based on a 1Dfinite moving source model propagating unilaterally with uniform velocity,the rupture transmission in one direction is superior to that in other directions.According to the Doppler Effect in the earthquake rupture process,the seismic wave frequency received by earthquake stations changes in different directions and thus,we can use the directional change of the corner frequency of the P or S waves to obtain the source parameters of the fault plane.In this article,the azimuth of rupture propagation direction and source parameters of the fault plane of the July 20,2012,MS4.9earthquake at the boundary zone of Gaoyou and Baoying in Jiangsu Province are obtained using the directional change of the corner frequency of the P and S waves,respectively.The azimuth angle of the fault plane for this earthquake was determined to be 232°by the P waves and 233.5°by the S waves,the seismic Mach number(v/c)was about 0.18 by the P waves and 0.23 by the S waves,and the fault length was about 0.26 km by the P waves and 0.18 km by the S waves.The result inverted by the corner frequency of the P and S waves is consistent,which shows that the azimuth angle of the fault plane for this earthquake was about 232°.Because of the lack of a near-station record at an azimuth of 49°,the inversion method is based on a 1Dfinite moving source model propagating unilaterally with uniform velocity.Therefore,the result of a rupture azimuth of 232°cannot represent a rupture propagating in the direction from NE to SW;it only indicates that the rupture surfaces were aligned in that direction.The seismic Mach number was about 0.2,which shows that the rupture velocity was smaller than the S wave velocity,and the fault length was about 0.2~0.3km.Many scholars have studied the seismogenic structure of the earthquake on July 20,2012,using a variety of methods such as focal mechanism solutions,field seismic intensity investigations,and relocation for aftershocks;however,the results have not been the same.The results of focal mechanism solutions show that the strike angle of one fault plane is 14°~28°in the NNE direction,whereas the strike angle of the other is in the NWW direction.Analysis shows that the fault plane might be in the NNE direction;however,the results of both field seismic intensity investigations and relocation for aftershocks show the fault plane might be in the NE direction.Our result show that the fault plane is aligned NE-SW,which is in accordance with the field seismic intensity investigations and relocation for aftershocks.The result inverted by the corner frequency of the P and S waves is consistent,showing a rupture azimuth with NE-SW alignment,which indicates that this method is meaningful in the fitting of the azimuth angle of an earthquake fault plane.Combined with regional geological structural data,we suggest that the Chuhe fault is likely to be the seismogenic structure of the MS4.9earthquake at the boundary zone of Gaoyou and Baoying.
引文
[1]刘建达,杨伟林,李丽梅,等.江苏高邮—宝应交界4.9级地震震害分析[J].中国地震,2012,28(4):402-414.LIU Jian-da,YANG Wei-lin,LI Li-mei,et al.Damage Survey and Analysis on Earthquake(MS=4.9)at the Boundary Zone of Gaoyou and Baoying,Jiangsu Province[J].Earthquake Research in China,2012,28(4):402-414.(in Chinese)
    [2]卓钰如,李文香.用多普勒效应研究中小地震的破裂面和破裂传播速度[J].地震学报,1982,4(1):14-26.ZHUO Yu-ru,LI Wen-xiang.Study on the Rapture Surface and Rapture Propagation Speed of Moderate and Small Earthquakes Using Doppler Effect[J].Acta Seismologica Sinica,2011,1982,4(1):14-26.(in Chinese)
    [3]Frankel A,Fletcher J,Vernon F,et al.Rupture Characteristics and Tomographic Source Imaging of M3Earthquakes Near Anza.Southern California[J].J Geophys Res,1986,91:12633-12650.
    [4]Badawv A,Abdel-Fattah A K.Source Parameters and Fault plane Determinations of the 28th Dec.,1999 Northern Cairo Earthquake[J].Tectonophysics,2001,334(1-2):63-77.
    [5]Abdel-Fattah A K.An Approach to Investigate Earthquake Rupture Processes[J].Acta Geophysica Polonica,2003,51(3):257-269.
    [6]许向彤,陈运泰,王培德.1995年7月20日怀来盆地ML=4.1地震的破裂过程[J].地震学报,1999,21(6):570-582.XU Xiang-tong,CHEN Yun-tai,WANG Pei-de.Pupture Process of the ML=4.1Earthquake in Huailai Basin on July20,1995[J].Acta Seismologica Sinica,1999,21(6)::570-582.(in Chinese)
    [7]许向彤,陈运泰,王培德.1995年7月20日怀来盆地ML=4.1地震序列参数的精确测定[J].地震学报,2001,23(3):225-238.XU Xiang-tong,CHEN Yun-tai,WANG Pei-de.Precise Determination of Focal Parameter of the ML=4.1 Earthquake in Huailai Basin on July 20,1995[J].Acta Seismologica Sinica,2001,23(3):225-238.(in Chinese)
    [8]陈学忠,王琼,刘冬英.1995年河北沙城ML4.1地震发震断层参数测定[J].地震,2005,25(2):69-74.CHEN Xue-zhong,WANG Qiong,LIU Dong-ying.Fault Plane Determination for the 1995 ML4.1Shacheng Earthquake,Huabei Province[J].Earthquake,2005,25(2):69-74.(in Chinese)
    [9]刘泽民,张军,沈小七,等.安徽两次中等地震发震断层参数确定[J].华南地震,2008,28(3):89-94.LIU Ze-min,ZHANG Jun,SHEN Xiao-qi,et al.Determination of Fault Plane Parameters of Two Medium Earthquakes in Anhui[J].South China Journal of Seismolog,2008,28(3):89-94.(in Chinese)
    [10]阮祥,程万正.云南鲁甸3次MS≥5.0地震破裂参数的研究[J].地震学报,2008,30(1):97-102.RUAN Xiang,CHENG Wan-zheng.Rupture Parameters of Three Ludian,Yunnan,MS≥5.0Earthquakes[J].Acta Seismologica Sinica,2008,30(1):97-102.(in Chinese)
    [11]陈学忠,吕坚,王慧敏.2005年11月26日江西九江—瑞昌MS5.7地震序列的破裂过程研究[J].地震,2008,28(1):100-106.CHEN Xue-zhong,Lvjian,WANG Hui-min.Investigation on Rupture Process of the Jiujiang—Ruichang MS5.7Earthquake Sequence of November 26,2005[J].Earthquake,2008,28(1):100-106.(in Chinese)
    [12]李艳娥,郭祥云,王恒信,等.2011年5月20日山东安丘ML3.7地震发震断层参数测定[J].地震,2012,32(3):52-58.LI Yan-e,GUO Xiang-yun,WANG Heng-xin,et al.Fault Plane Determination for the 2011 ML3.7Anqiu Earthquake,Shandong Province[J].Earthquake,2012,32(3):52-58.(in Chinese)
    [13]Andrews D J.Objective Determination of Source Parameters and Similarity of Earthquakes of Different Size[C]//Das S,Boatwright J,Scholz C H.Earthquake Source Mechanics Washington DC:AGU,1986,259-267.
    [14]王鹏,郑建常,赵金花.胶东半岛地区震源谱参数研究[J].地震工程学报,2013,35(2):360-365.WANG Peng,ZHEN Jian-chang,ZHAO Jin-hua.Status of Seismic Source Spectral Parameters in the Jiaodong Peninsula[J].China Earthquake Engineering Journal,2013,35(2):360-365.(in Chinese)
    [15]徐果明,周惠兰.地震学原理[M].北京:科学出版社,1982,397-400.XU Guo-min,ZHOU Hui-lan.Elements of Seismology[M].Beijing:Science Press,1982,397-400.(in Chinese)
    [16]Ben-Menhaem A.Radiation of Seismic Body Waves From a Finite Moving Source in the Earth[J].J Geophys Res,1962,67:345-350.
    [17]洪德全,王行舟,倪红玉,等.多种数字地震学方法研究2012年7月20日江苏高邮MS4.9级地震震源机制解和震源深度[J].地球物理学进展,2013,28(4):1757-1765.HONG De-quan,WANG Xing-zhou,NI Hong-yu,et al.Focal Mechanism and Focal Depth of July 20,2012Jiangsu Gaoyou MS4.9Earthquake[J].Progress in Geophys,2013,28(4):1757-1765.(in Chinese)
    [18]孙业君,王俊,黄耘.2012年7月20日江苏高邮—宝应M4.9地震震源机制解[J].防灾减灾工程学报,2012,32(4):521-522.SUN Ye-jun,WANG Jun,HUANG Yun.Focal Mechanism Solution of M4.9Earthquake for 20July 2012Gaoyou—Baoying,Jiangsu Province[J].Journal of Disaster Prevention and Mitigation Engineering,2012,32(4):521-522.(in Chinese)
    [19]李钦祖,靳雅敏,于新昌.华北地区的震源机制与地壳应力场[J].地震学报,1982,4(1):55-61.LI Qin-zu,JIN Ya-min,YU Xin-chang.Focal Mechanism Solution and Crust Stress Field of North China Region[J].Acta Seismologica Sinica,1982,4(1):55-61.(in Chinese)
    [20]刘佳敏,任烨,尹欣欣.江苏宝应4.9级地震序列双差定位处理[J].地震地磁观测与研究,2013,34(3):22-24.LIU Jia-min,REN Ye,Yin Xin-xin.Relocation of the Earthquake Sequence of M4.9 Which Happened in Baoying County,Jiangsu Province With the Double Difference Location Method[J].Seismological Andgeomagnetic Observation and Research,2013,34(3):22-24.(in Chinese)
    [21]倪红玉,刘泽民,何康.郯庐断裂带安徽段中小地震震源机制及现代应力场特征[J].地震工程学报,2013,35(3):677-683.NI Hong-yu,LIU Ze-min,HE Kang.Study on Focal Mechanisms of Moderate-small Earthquakes and Characteristics of Recent Tectonic Stress Field in the Anhui Sector of Tanlu Fault Zone[J].China Earthquake Engineering Journal,2013,35(3):677-683.(in Chinese)
    [22]王斌,周健,梁雪萍.江苏盐城附近及邻近海域地震活动分析[J].防灾减灾工程学报,2008,10(3):56-60.WANG Bin,ZHOU Jian,LIANG Xue-ping.Analysis on Seismic Activity Near Yancheng and Neighboring Sea Area[J].Journal of Disaster Prevention and Mitigation Engineering,2008,10(3):56-60.(in Chinese)
    [23]宋传中,朱光,王道轩,等.苏皖境内滁河断裂的演化与大地构造背景[J].中国区域地质,2000,19(4):367-374.SONG Chuang-zhong,ZHU Guang,WANG Dao-xuan,et al.Evolution of the Chuhe Fault in Jiangsu and Anhui and Tectonic Setting[J].Regional Geology of China,2000,19(4):367-374.(in Chinese)
    [24]张恩立,张寅生,郑树杰,等.郯庐断裂带皖东段与滁河断裂构造及地震活动相关性研究[J].防灾减灾工程学报,2004,24(2):202-209.ZHANG en-li,ZHANG Yin-sheng,ZHEN Shu-jie,et al.Correlation of Tectonics and Seismicity in Tancheng—Lujiang Fault Zone in East Anhui and Chuhe Fault[J].Journal of Disaster Prevention and Mitigation Engineering,2004,24(5):202-209.(in Chinese)

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