江苏南部地区现今震源机制和应力场特征
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摘要
利用2000年3月至2014年4月江苏及邻区数字地震波形资料,采用P波、S波初动和振幅比求解方法计算了江苏南部地区123次中小地震震源机制解。分析震源机制解特征表明,研究区中小地震震源类型以走滑型为主,其次为正断层类型,P、T轴优势方向分别为NEE—SWW和NNW—SSE向。依据盆地和断裂发育、历史及现代中小地震分布、震源机制等特征将研究区划分为A区和B区。采用Gphart方法分别反演了这两个区域应力张量,结果显示:A区最大主应力方位角为78°,倾角为23°,最小主应力方位角为340°,倾角为17°;B区最大主应力方位角为60°,倾角为25°,最小主应力方位角为330°,倾角为1°。两个分区应力场结果的差异显示了局部应力场的不均匀性,体现了局部地区地质条件、构造活动等差异性。各分区应力场特征与区内的中强地震震源机制特征较为一致,这在一定程度也佐证了反演结果的可靠性。
Using the digital seismic waveform data in Jiangsu and its adjacent area during M ar., 2000 and Apr.,2014,we calculated the focal mechanisms of 123 moderate and small earthquakes in southern Jiangsu area by the method of amplitude ratio of P wave and S wave. The characteristics of the focal mechanism solution shows that the main type of the small and moderate earthquake in the study area is strike-slip type,secondly for normal fault type,and the predominant orientations of P and T axes are NEE—SWW and NNW —SSE respectively. On the basis of the development of basin and faults,the distribution of historical and modern earthquakes and the characteristics of focal mechanism etc.,we divided the study area into A and B regions and inverted the stress tensor of the two regions by Gphart method. The result shows that the azimuth and dip of maximum principal stress is 78° and 23° in A region,is 60° and 25° in B region respectively,and the azimuth and dip of minimum principal stress is 340° and 17° in A region,is 330° and 1° in B region respectively. The differences of stress field in the two regions showed the heterogeneity of the regional stress field,which reflected the differences of geological conditions and the tectonic activity etc.. The characteristics of stress field in the two regions were coincident with focal mechanism of the modern-strong earthquake in the study area,which proved the reliability of the inversion results.
引文
崔效锋,谢富仁.2006.川滇地区现代构造应力场分区及动力学意义[J].地震学报,28(5):451-461.
    杜兴信,邵辉成.1999.由震源机制解反演中国大陆现代构造应力场[J].地震学报,21(4):354-360.
    范小平,李清河,杨从杰,等.2009a.S波包络时间差影响因素的数值分析[J].地震学报,31(4):367-376
    范小平,李清河,杨从杰,等.2009b.长白山天池火山区介质非均匀性[J].地球物理学报,52(10):2580-2587.
    范小平,李清河,杨从杰,等.2011.长白山天池火山区介质速度非均匀性谱结构[J].地球物理学报,54(5):1215-1221.
    范小平,杨从杰,李清河,等.2013.介质非均匀性参数对散射波包络的影响[J].地球物理学进展,28(2):687-694.
    郭祥云,陈学忠,王生文,等.2014.川滇地区中小地震震源机制解及构造应力场的研究[J].地震工程学报,36(3):599-607.
    胡连英,徐学思,孙寿成,等.1997.溧阳地震与茅东断裂带[M].北京:地震出版社.
    黄耘,李清河,张元生,等.2011.郯庐断裂带鲁苏皖段及邻区地壳速度结构[J].地球物理学报,54(10):2549-2559.
    康英,杨选,陈杏,等.2008.广东及邻区的应力场反演[J].地震学报,30(1):59-66.
    李瑞莎,崔效锋,刁桂苓,等.2008.华北北部地区现今应力场时空变化特征研究[J].地震学报,30(6):570-580.
    李莹甄,沈军,聂晓红,等.2011.乌鲁木齐地区现今构造应力场综合分析[J].地震学报,33(1):15-27.
    林向东,徐平,葛洪魁,等.2011.小江断裂中段及其邻近地区应力场时间变化分析[J].地震学报,33(6):755-762.
    刘泽民,刘东旺,李玲利,等.2011.利用多个震源机制解求东大别地区平均应力场[J].地震学报,33(5):605-613.
    汪素云,许忠淮.1985.中国东部大陆的地震构造应力场[J].地震学报,7(1):17-32.
    王熠熙,张辉.2013.利用多个震源机制解求祁连山西段平均应力场方向[J].地震工程学报,35(2):289-295.
    谢富仁,崔效锋,赵建涛,等.2004.中国大陆及邻区现代构造应力场分区[J].地球物理学报,47(4):654-662.
    谢富仁,张红艳,崔效锋,等.2011.中国大陆构造应力场与强震活动[J].国际地震动态,(1):4-12.
    徐鸣洁,姜永基,周翠英.1996.江苏及邻区现代应力场空间分布特征分析[J].中国地震,12(4):383-388.
    许忠淮,汪素云,黄雨蕊,等.1989.由大量的地震资料推断的我国大陆构造应力场[J].地球物理学报,32(6):636-647.
    许忠淮.1985.用滑动方向拟合法反演唐山余震区的平均应力场[J].地震学报,7(4):349-361.
    张红艳,谢富仁,崔效锋,等.2014.北天山中东段活动断层滑动与现代构造应力场[J].中国地震,30(1):13-22.
    张红艳,谢富仁,荆振杰.2009.京西北盆岭构造区现代构造应力场的非均匀特征[J].地球物理学报,52(12):3061-3071.
    张绍治,吴少武,刘仲方.1989.江苏地区现代构造应力场特征[J].江苏地质,(2):3-9.
    张肇诚.2000.中国震例(1989—1991)[M].北京.地震出版社.
    郑建常,王鹏,李冬梅,等.2013.使用小震震源机制解研究山东地区背景应力场[J].地震学报,35(6):773-784.
    钟继茂,程万正.2006.由多个地震震源机制解求川滇地区平均应力场方向[J].地震学报,28(4):337-346.
    周翠英,王铮铮,蒋海昆,等.2005.华东地区现代地壳应力场及地震断层错动性质[J].地震地质,27(2):273-288.
    Angelier J..1979.Determination of the Mean Principal Direction of Stresses for a Given Fault Population[J].Tectonophysics,56(4):17-26.
    Chung W.Y.,Wei B.Z.,Brantley B.J..1995.Faulting Mechanism othe Liyang,China,Earthquake of 1974 and 1979 from Regional andTeleseismic Waveform———Evidence of Tectonic Inversion under aFault-Bounded Basin[J].BSSA,85(2):560-570.
    Ellsworth W.L,Xu Z.H..1980.Determination of the Stress Tensor fromFocal Mechanism data[J].EOS,Transactions American GeophysicaUnion,61(46):1117.
    Gephart J.W.,Forsyth D.W..1984.An Improved Method for Determining the Regional Stress Tensor Using Focal Mechanism Data:Application to the San Fernando Earthquake Sequence[J].Journal of Geophysical Research,89(B11):9305-9320.
    Gephart J.W..1990.FMSI:A Fortran Program for Inverting Fauh/Shckenside and Earthquake Focal Mechanism Data to Obtain the Regional Stress Tensor[J].Computer&Geosciences,16(7):953-989.
    Michael A.J..1984.Determination of Stress from Slip Data:Faults andFolds[J].Journal of Geophysical Research,89(B13):11517-l1526.
    Snoke J.A.,Munsey J.W.,Teague A.G.,et al..1984.A Program forFocal Mechanism Determination by Combined Use of Polarity andSV2P Amplitude Ratio Data[J].Earthquake Notes,55(3):15-20.
    Snoke J.A..1989.Earthquake Mechanism[A]//James D E.Encyclopedia of Geophysics[C].New York:Van Nostrand Reinhold Company,239-245.
    Wan Y.G..2010.Contemporary Tectonic Stress Field in China[J].Earthquake Science,23(4):377-386.
    Zoback M.L..1992.First-and Second-Order Patterns of Stress in theLithosphere:The World Stress Map Project[J].Journal of Geophysical Research.,97(B8):11703-11728.
    ①江苏省地震工程研究院.2004.沪宁高速公路(江苏段)扩建工程场地地震安全性评价工作报告(JSE2004A024).

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