胶东半岛地区震源波谱参数研究
|
摘要
利用山东数字地震台网记录到的胶东半岛及附近地区2010年以来的地震波形资料,采用Brune模型,并结合遗传算法反演了本区134次2.0级以上地震的震源波谱参数。结果表明胶东半岛地区中小地震的地震矩在9.76×1011～5.9×1014 N.M之间;应力降范围在0.017～25MPa之间,均值是0.97MPa;视应力范围在0.06～10.2MPa,平均应力水平在0.396MPa。地震矩、应力降和视应力都与震级呈正相关关系,拐角频率与震级的关系不是很明显;地震矩和拐角频率成负相关关系。根据本区震源参数和震级的定量统计关系,去除震级影响,通过应力降和视应力随时间的变化得到目前正处于应力的释放时期。
Source parameters calculations are generally carried out in the frequency domain.Seismic wave data from station records can be used for site response,instrument response,geometric diffusion path attenuation,and focal radiation directivity factor correction.A genetic algorithm can be used to obtain the parameters of low-frequency spectral amplitude limit and corner frequency,and thus,the theoretical formula for calculating stress drop,source radius,and seismic moment.The geological structure of Jiaodong Peninsula is complex.The area spread by the Jiaodong fault was uplifted,and the area of the northern Yellow Sea fault was bent,so the Jiaodong Peninsula fault structure is mainly monoclinic or relief synclinic.Brittle faults are well developed,mainly related to the eastern section of the Yanshan-Bohai fault zone.In contrast,at the intersection with the Tan-Lu fault in the Bohai are two sets of faults in the NNE-NE and NWW directions.The faults in the area are strong,and the structure is extremely complex;this was a high activity area in the North China earthquake.In recent years,the seismic activity has concentrated and strengthened.Regional stress changes have been analyzed in recent years in order to study the risk to Jiaodong Peninsula of strong earthquakes.Based on digital seismograms of Jiaodong Peninsula and the surrounding areas recorded by the Shandong digital seismic network since 2010,the Brune model,combined with a genetic algorithm,has been used to calculate the spectral parameters of 134 earthquakes above 2.0 in the Jiaodong Peninsula.Results show that seismic moments were between 9.76 × 1011 N·m and 5.9 × 1014 N·m;pressure drops were between 0.017 MPa and 25 MPa(0.97 MPa mean);and apparent pressures were between 0.06 MPa and 10.2 MPa(0.396 MPa mean).Seismic moment,stress drop,and apparent stress were positively correlated with magnitude,with the magnitude of the rise increasing.By using a linear fit of robust regression functions,a quantitative relationship has been developed for the Jiaodong Peninsula,which is consistent with the findings of other scholars.The relationship between corner frequency and magnitude is not obvious;seismic moment and corner frequency were negatively correlated.According to the quantitative statistical relationships between the Jiaodong Peninsula source parameters and magnitude(in addition to the effect of magnitude),and by the changes in stress drop and apparent stress over time,we can clearly see that a Jiaodong Peninsula stress adjustment has caused the stress to currently be in a period of weakening,compared to its previous high-stress state.
Source parameters calculations are generally carried out in the frequency domain.Seismic wave data from station records can be used for site response,instrument response,geometric diffusion path attenuation,and focal radiation directivity factor correction.A genetic algorithm can be used to obtain the parameters of low-frequency spectral amplitude limit and corner frequency,and thus,the theoretical formula for calculating stress drop,source radius,and seismic moment.The geological structure of Jiaodong Peninsula is complex.The area spread by the Jiaodong fault was uplifted,and the area of the northern Yellow Sea fault was bent,so the Jiaodong Peninsula fault structure is mainly monoclinic or relief synclinic.Brittle faults are well developed,mainly related to the eastern section of the Yanshan-Bohai fault zone.In contrast,at the intersection with the Tan-Lu fault in the Bohai are two sets of faults in the NNE-NE and NWW directions.The faults in the area are strong,and the structure is extremely complex;this was a high activity area in the North China earthquake.In recent years,the seismic activity has concentrated and strengthened.Regional stress changes have been analyzed in recent years in order to study the risk to Jiaodong Peninsula of strong earthquakes.Based on digital seismograms of Jiaodong Peninsula and the surrounding areas recorded by the Shandong digital seismic network since 2010,the Brune model,combined with a genetic algorithm,has been used to calculate the spectral parameters of 134 earthquakes above 2.0 in the Jiaodong Peninsula.Results show that seismic moments were between 9.76 × 1011 N·m and 5.9 × 1014 N·m;pressure drops were between 0.017 MPa and 25 MPa(0.97 MPa mean);and apparent pressures were between 0.06 MPa and 10.2 MPa(0.396 MPa mean).Seismic moment,stress drop,and apparent stress were positively correlated with magnitude,with the magnitude of the rise increasing.By using a linear fit of robust regression functions,a quantitative relationship has been developed for the Jiaodong Peninsula,which is consistent with the findings of other scholars.The relationship between corner frequency and magnitude is not obvious;seismic moment and corner frequency were negatively correlated.According to the quantitative statistical relationships between the Jiaodong Peninsula source parameters and magnitude(in addition to the effect of magnitude),and by the changes in stress drop and apparent stress over time,we can clearly see that a Jiaodong Peninsula stress adjustment has caused the stress to currently be in a period of weakening,compared to its previous high-stress state.
引文
[1]Moya C A,Aguirre J,Irikura K.Inversion of Source Parame-ters and Site Effects from Strong Ground Motion Records U-sing genetic Algorithms[J].B.S.S.A.,2000,90(4):977-992.
[2]Bindi D,Spallarossa D,Augliera P,et al.Source Parameters Es-timated from the Aftershocks of the 1997Umbria-Marche(It-aly)Seismic Sequence[J].B.S.S.A.,2001,91:448-455.
[3]Giampiccolo E,D Amico S,Patane D,et al.Attenuation andSource Parameters of Shallow Microearthquakes at Mt.EtnaVolcano,Italy[J].B.S.S.A.,2007,97:184-197.
[4]朱新运,于俊谊.基于MATLAB的小震震源参数计算软件研制[J].西北地震学报,2008,30(4):380-384.ZHU Xin-yun,YU Jun-yi.The Data Processing Software ofSource Parameters for Middle or Small Earthquakes Based onMATLAB[J].Northwestern Seismological Journal,2008,30(4):380-384.
[5]于俊谊,朱新运.浙江珊溪水库地震震源参数研究[J].中国地震,2008,24(4):379-387.YU Jun-yi,ZHU Xin-yu.Hypocentral Parameters Researchof the Shanxi Reservoir Area in Zhejiang[J].Earthquake Re-search in China,2008,24(4):379-387.
[6]阮祥,程万正,乔惠珍,等.安宁河—则木河地震带震源参数及应力状态的研究[J].西北地震学报,2011,33(1):46-50.RUAN Xiang,CHENG Wan-zheng,QIAO Hui-zhen,et al.Research on Source Parameters and Stress State in Anninghe-Zemuhe Earthquake Belt[J].Northwestern SeismologicalJournal,2011,33(1):46-50.
[7]潘振生,刘辉,谷美菊,等.新疆柯坪块体震源参数的初步研究与应用[J].西北地震学报,2010,32(1):357-362.PAN Zhen-sheng,LUI Hui,GU Mei-ju,et al.PreliminaryStudy on Source Parameters of Earthquakes Occurred inKeping Block,Xinjiang[J].Northwestern Seismological Jour-nal,2010,32(1):357-362.
[8]刘薇,张晓清,石玉成,等.利用格林函数库计算2008年青海大柴旦6.4级地震的余震震源机制[J].西北地震学报,2012,34(2):154-160.LIU Wei,ZHANG Xiao-qing,SHI Yu-cheng,et al.UsingGreen Function Database and Quick Moment Tensor InversionCalculating the Focal Mechanism Solution of Aftershocks ofDachaidan MS6.4Earthquake in 2008in Qinghai Province[J].Northwestern Seismological Journal,2012,34(2):154-160.
[9]张永久,乔慧珍.紫坪铺水库库区震源波谱参数研究[J].西北地震学报,2011,33(2):117-122.ZHANG Yong-jiu,QIAO Hui-Zhen.Study on Seismic SourceParameters in Zipingpu Reservoir Area[J].NorthwesternSeismological Journal,2011,33(2):117-122.
[10]钟羽云,朱新运,张震峰.不同类型地震的地震矩-震级标度关系研究[J].西北地震学报,2004,26(1):57-61.ZHONG Yu-yun,ZHU Xin-yun,ZHANG Zhen-feng.Studyon Relations between Seismic Moment and Magnitude for Va-rious Types of Earthquake Sequence[J].Northwestern Seis-mological Journal,2004,26(1):57-61.
[11]李一正.滇西地区震级与地震矩标度[J].地震研究,1985,8(6):617-632.LI Yi-zheng.The Western Yunnan Magnitude and SeismicMoment Scale[J].Journal of Seismological Research,1985,8(6):617-632.
[12]秦嘉政.用近震尾波估算昆明及其周围地区的Q值和地震矩[J].地球物理学报,1986,29(2):145-156.QI Jia-zheng.Nearly Coda Q Value Estimate Kunming andIts Surroundings and Seismic Moment[J].Geophysics,1986,29(2):145-156.
[13]李立平,叶建庆,谢庆茵.谰沧—耿马地震震源动力学参数研究[J].地震研究,1990,13(3):223-232.LI Li-ping,YE Jian-qing,XIE Qing-yin.A Research on Fo-cal Dynamic Parameters of Lancang-Gengma Earthquake[J].Journal of Seismological Research,1990,13(3):223-232.
[14]刘学军,叶建庆,蔡绍平.姚安地震序列的震源参数研究[J].地震研究,2002,25(3):240-245.LIU Xue-jun,YE Jian-qing,CAI Shao-pin.Study on FocalParameters for the Yao-an Earthquake Sequence[J].Jour-nal of Seismological Research,2002,25(3):240-245.
[15]张永久,程万正.用S波研究雅江地震序列震源波谱[J].中国地震,2003,19(4):340-350.ZHANG Yong-jiu,CHENG Wan-zheng.Study on SourceParameters for the Yajiang Earthquake SequenceUsing Swave[J].Earthquake Research in China,2003,19(4):340-350.
[16]师海阔,朱新运,贺永忠.宁夏及邻区地震震源参数研究[J].大地测量与地球动力学,2010,30(增刊):38-43.SHI Hai-kuo,ZHU Xin-yun,HE Yong-zhong.Research onHypocentral Parameters of Ningxia and Adjacent Region[J].Journal of Geodesy and Geodynamics,2010,30(Supp.):38-43.
[17]钟羽云,朱新运.温州珊溪水库ML3.9震群震源参数特征[J].地震,2004,24(3):107-114.ZH0NG Yu-yun,ZHU Xin-yun,ZHANG Zhen-feng.SourceParameter Characteristics of ML3.9Earthquake Swarm Oc-curred in Shanxi Reservoir,Wenzhou,Zhejiang Provine[J].Earthquake,2004,24(3):107-114.
[18]李发,李罡风,裴红云.安庆4.8级地震序列的地震波谱变化研究[J].高原地震,2012,24(1):23-27.LI Fa,LI Gang-feng,PEI Hong-yun.Study on Seismic WaveSpectrum of Anqing M4.8Earthquake Sequence[J].PlateauEarthquake Research,2012,24(1):23-27.
[19]盛书中,万永革.地震视应力及其物理意义的探讨[J].地震地磁观测研究,2008,29(1):36-43.SHENG Shu-zhong,WAN Yong-ge.Apparent Stress andthe Discussion of Its Physical Implication[J].Seismologicaland Geomagnetic Observation and Research,2008,29(1):36-43.
[20]吴忠良,黄静,林碧苍.中国西部地震视应力的空间分布[J].地震学报,2002,24(3):294-301.WU Zhong-liang,HUANG Jing,LIN Bi-cang.Distributionof Apparent Stress in Western china[J].Acta SeismologicaSinica,2002,24(3):294-301.
[21]邬成栋,付虹,赵小艳.小湾水库近场区地震震源参数初步研究[J].地震研究,2010,33(1):50-54.WU Cheng-dong,FU Hong,ZHAO Xiao-yan.PrimaryStudy on Source Parameters near Xiaowan Reservoir[J].Journal of Seismological Research,2010,33(1):50-54.
[2]Bindi D,Spallarossa D,Augliera P,et al.Source Parameters Es-timated from the Aftershocks of the 1997Umbria-Marche(It-aly)Seismic Sequence[J].B.S.S.A.,2001,91:448-455.
[3]Giampiccolo E,D Amico S,Patane D,et al.Attenuation andSource Parameters of Shallow Microearthquakes at Mt.EtnaVolcano,Italy[J].B.S.S.A.,2007,97:184-197.
[4]朱新运,于俊谊.基于MATLAB的小震震源参数计算软件研制[J].西北地震学报,2008,30(4):380-384.ZHU Xin-yun,YU Jun-yi.The Data Processing Software ofSource Parameters for Middle or Small Earthquakes Based onMATLAB[J].Northwestern Seismological Journal,2008,30(4):380-384.
[5]于俊谊,朱新运.浙江珊溪水库地震震源参数研究[J].中国地震,2008,24(4):379-387.YU Jun-yi,ZHU Xin-yu.Hypocentral Parameters Researchof the Shanxi Reservoir Area in Zhejiang[J].Earthquake Re-search in China,2008,24(4):379-387.
[6]阮祥,程万正,乔惠珍,等.安宁河—则木河地震带震源参数及应力状态的研究[J].西北地震学报,2011,33(1):46-50.RUAN Xiang,CHENG Wan-zheng,QIAO Hui-zhen,et al.Research on Source Parameters and Stress State in Anninghe-Zemuhe Earthquake Belt[J].Northwestern SeismologicalJournal,2011,33(1):46-50.
[7]潘振生,刘辉,谷美菊,等.新疆柯坪块体震源参数的初步研究与应用[J].西北地震学报,2010,32(1):357-362.PAN Zhen-sheng,LUI Hui,GU Mei-ju,et al.PreliminaryStudy on Source Parameters of Earthquakes Occurred inKeping Block,Xinjiang[J].Northwestern Seismological Jour-nal,2010,32(1):357-362.
[8]刘薇,张晓清,石玉成,等.利用格林函数库计算2008年青海大柴旦6.4级地震的余震震源机制[J].西北地震学报,2012,34(2):154-160.LIU Wei,ZHANG Xiao-qing,SHI Yu-cheng,et al.UsingGreen Function Database and Quick Moment Tensor InversionCalculating the Focal Mechanism Solution of Aftershocks ofDachaidan MS6.4Earthquake in 2008in Qinghai Province[J].Northwestern Seismological Journal,2012,34(2):154-160.
[9]张永久,乔慧珍.紫坪铺水库库区震源波谱参数研究[J].西北地震学报,2011,33(2):117-122.ZHANG Yong-jiu,QIAO Hui-Zhen.Study on Seismic SourceParameters in Zipingpu Reservoir Area[J].NorthwesternSeismological Journal,2011,33(2):117-122.
[10]钟羽云,朱新运,张震峰.不同类型地震的地震矩-震级标度关系研究[J].西北地震学报,2004,26(1):57-61.ZHONG Yu-yun,ZHU Xin-yun,ZHANG Zhen-feng.Studyon Relations between Seismic Moment and Magnitude for Va-rious Types of Earthquake Sequence[J].Northwestern Seis-mological Journal,2004,26(1):57-61.
[11]李一正.滇西地区震级与地震矩标度[J].地震研究,1985,8(6):617-632.LI Yi-zheng.The Western Yunnan Magnitude and SeismicMoment Scale[J].Journal of Seismological Research,1985,8(6):617-632.
[12]秦嘉政.用近震尾波估算昆明及其周围地区的Q值和地震矩[J].地球物理学报,1986,29(2):145-156.QI Jia-zheng.Nearly Coda Q Value Estimate Kunming andIts Surroundings and Seismic Moment[J].Geophysics,1986,29(2):145-156.
[13]李立平,叶建庆,谢庆茵.谰沧—耿马地震震源动力学参数研究[J].地震研究,1990,13(3):223-232.LI Li-ping,YE Jian-qing,XIE Qing-yin.A Research on Fo-cal Dynamic Parameters of Lancang-Gengma Earthquake[J].Journal of Seismological Research,1990,13(3):223-232.
[14]刘学军,叶建庆,蔡绍平.姚安地震序列的震源参数研究[J].地震研究,2002,25(3):240-245.LIU Xue-jun,YE Jian-qing,CAI Shao-pin.Study on FocalParameters for the Yao-an Earthquake Sequence[J].Jour-nal of Seismological Research,2002,25(3):240-245.
[15]张永久,程万正.用S波研究雅江地震序列震源波谱[J].中国地震,2003,19(4):340-350.ZHANG Yong-jiu,CHENG Wan-zheng.Study on SourceParameters for the Yajiang Earthquake SequenceUsing Swave[J].Earthquake Research in China,2003,19(4):340-350.
[16]师海阔,朱新运,贺永忠.宁夏及邻区地震震源参数研究[J].大地测量与地球动力学,2010,30(增刊):38-43.SHI Hai-kuo,ZHU Xin-yun,HE Yong-zhong.Research onHypocentral Parameters of Ningxia and Adjacent Region[J].Journal of Geodesy and Geodynamics,2010,30(Supp.):38-43.
[17]钟羽云,朱新运.温州珊溪水库ML3.9震群震源参数特征[J].地震,2004,24(3):107-114.ZH0NG Yu-yun,ZHU Xin-yun,ZHANG Zhen-feng.SourceParameter Characteristics of ML3.9Earthquake Swarm Oc-curred in Shanxi Reservoir,Wenzhou,Zhejiang Provine[J].Earthquake,2004,24(3):107-114.
[18]李发,李罡风,裴红云.安庆4.8级地震序列的地震波谱变化研究[J].高原地震,2012,24(1):23-27.LI Fa,LI Gang-feng,PEI Hong-yun.Study on Seismic WaveSpectrum of Anqing M4.8Earthquake Sequence[J].PlateauEarthquake Research,2012,24(1):23-27.
[19]盛书中,万永革.地震视应力及其物理意义的探讨[J].地震地磁观测研究,2008,29(1):36-43.SHENG Shu-zhong,WAN Yong-ge.Apparent Stress andthe Discussion of Its Physical Implication[J].Seismologicaland Geomagnetic Observation and Research,2008,29(1):36-43.
[20]吴忠良,黄静,林碧苍.中国西部地震视应力的空间分布[J].地震学报,2002,24(3):294-301.WU Zhong-liang,HUANG Jing,LIN Bi-cang.Distributionof Apparent Stress in Western china[J].Acta SeismologicaSinica,2002,24(3):294-301.
[21]邬成栋,付虹,赵小艳.小湾水库近场区地震震源参数初步研究[J].地震研究,2010,33(1):50-54.WU Cheng-dong,FU Hong,ZHAO Xiao-yan.PrimaryStudy on Source Parameters near Xiaowan Reservoir[J].Journal of Seismological Research,2010,33(1):50-54.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心