考虑到时误差的地震定位算法及其在四川地区2001—2008年地震定位的应用
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摘要
精确的地震位置对于地震活动性、地震层析成像和地壳应力场反演具有相当重要的意义,对于地震速报也具有重要的应用价值。将观测到时的不确定性、台站高程、地震震源深度进行约束的同时,根据反演理论给出了地震震源位置精确估计和误差估计的方法。该算法联合考虑Pg波、Sg波、Pn波和Sn波的到时进行反演,数据量的增加可以增强地震位置的准确性,并可同时应用于地方震和区域地震。采用模拟数据对该地震定位算法进行检验发现,该算法在观测数据的不确定性不等时明显优于其他方法。将该算法应用于四川地区2001—2008年间的地震定位,得到的地震位置更加符合地震的丛集性并集中于断裂带附近。这些结果为四川地区的地震活动性、断层构造以及地震层析成像研究打下了基础,并且为汶川地震之前的地震活动前兆研究也提供了有益帮助。
The precisely located earthquake catalogue is important to seismicity,seismic tomography and crustal stress inversion studies.It also has great application value in rapid report of an earthquake that just occurred.By considering the arrival time uncertainty,and the constraints on station elevation and seismic depth,we propose a relatively accurate method to estimate hypocentral location and its uncertaintybased on inversion theory.Our method can combine the arrival times of Pg wave,Sg wave,Pn wave and Sn wave in hypocenter location,so it increases the location accuracy by involving more data;and it can be also used in local and regional earthquake location simultaneously.In order to test our location method,we located earthquakes by using the simulated data with different uncertainty of Pg,Sg,Pn,Sn arrivals.The result shows that the location determined by using our method is more accurate than that by using other method.We apply it to earthquakes occurring in the period from 2001 to 2008 in Sichuan area,and obtained a more clustered hypocentral distribution convergent to the fault zones.The result provides a solid foundation for studies of seismicity,geometry of the active faults and seismic tomography in Sichuan region.It is also helpful to study the seismicity precursors before the Wenchuan earthquake.
引文
牟磊育,赵仲和,张伟,等.2006.用INGLADA与GEIGER方法实现近震精定位[J].中国地震,22(3):294—302.MOU Lei-yu,ZHAO Zhong-he,ZHANG Wei,et al.2006.Using the INGLADA and GEIGER method to realize regional earthquake location accurately[J].Earthquake Research in China,22(3):294—302(in Chinese).
    万永革,李鸿吉.1995.遗传算法在确定震源位置中的应用[J].地震地磁观测与研究,16(6):1—7.WAN Yong-ge,LI Hong-ji.1995.The preliminary study on the seismic hypocenter location using genetic algorithms[J].Seismological and Geomagnetic Observation and Research,16(6):1—7(in Chinese).
    万永革,李清河,李鸿吉,等.1997.用遗传算法确定三维横向不均匀介质中的近震震源位置[J].西北地震学报,19(2):7—14.WAN Yong-ge,LI Qing-he,LI Hong-ji,et al.1997.Hypocentral locations of the near earthquakes in3-D lateral heterogeneous medium determined by the genetic algorithms[J].Northwestern Seismological Journal,19(2):7—14(inChinese).
    万永革,王敏,沈正康,等.2004.利用GPS和水准测量资料反演2001年昆仑山口西8.1级地震的同震滑动分布[J].地震地质,26(3):393—404.WAN Yong-ge,WANG Min,SHEN Zheng-kang,et al.2004.Co-seismic slip distribution of the2001west of KunlunMountain Pass earthquake inverted by GPS and leveling data[J].Seismology and Geology,26(3):393—404(inChinese).
    万永革,沈正康,刁桂苓,等.2008a.利用小震分布和区域应力场确定大震断层面参数方法及其在唐山地震序列中的应用[J].地球物理学报,51(3):793—804.WAN Yong-ge,SHEN Zheng-kang,DIAO Gui-ling,et al.2008a.An algorithm of fault parameter determination usingdistribution of small earthquakes and parameters of regional stress field and its application to Tangshan earthquakesequence[J].Chinese J Geophys,51(3):569—583(in Chinese).
    万永革,沈正康,王敏,等.2008b.根据GPS和InSAR数据反演2001年昆仑山口西地震同震破裂分布[J].地球物理学报,51(4):1074—1084.WAN Yong-ge,SHEN Zheng-kang,WANG Min,et al.,2008b.Coseismic slip distribution of the2001West KunlunMountain Pass earthquake constrained using GPS and InSAR data[J].Chinese J Geophysics,51(4):753—764.
    万永革,沈正康,盛书中,等.2009.2008年汶川大地震对周围断层的影响[J].地震学报,31(2):128—139.WAN Yong-ge,SHEN Zheng-kang,SHENG Shu-zhong,et al.2009.The influence of2008Wenchuan earthquake on surrounding faults[J].Acta Seismologica Sinica,31(2):128—139(in Chinese).
    王福昌,万永革,胡顺田.2008.粒子群算法在主震断层面参数估计中的应用[J].地震研究,31(2):149—154.WANG Fu-chang,WAN Yong-ge,HU Shun-tian.2008.Application of particle swarm optimization to the estimation ofmainshock fault plane parameters[J].Journal of Seismological Research,31(2):149—154(in Chinese).
    徐果明,周惠兰.1982.地震学原理[M].北京:科学出版社.XU Guo-ming,ZHOU Hui-lan.1982.Principle of Seismology[M].Science Press,Beijing(in Chinese).
    赵珠,丁志峰,易桂喜,等.1994.西藏地震定位:一种使用单纯形优化的非线性方法[J].地震学报,16(2):212—219.ZHAO Zhu,DING Zhi-feng,YI Gui-xi,et al.1994.Location of Tibetan earthquakes:A nonlinear approach by a simplex optimized technique[J].Acta Seismologica Sinica,16(2):212—219(in Chinese).
    赵珠,范军,郑斯华,等.1997.龙门山断裂带地壳速度结构和震源位置的精确修定[J].地震学报,19(6):615—622.ZHAO Zhu,FAN Jun,ZHENG Si-hua,et al.1997.Crustal structure and accurate hypocenter determination along theLongmenshan Fault zone[J].Acta Seismologica Sinica,19(6):615—622(in Chinese).
    赵仲和.1983.多重模型地震定位程序及其在北京台网的应用[J].地震学报,5(2):242—254.ZHONG Zhong-he.1983.An earthquake location program with multiple velocity model and its application in the Beijingseismic network[J].Acta Seismologica Sinica,5(2):242—254(in Chinese).
    周仕勇,许忠淮,韩京,等.1999.主地震定位方法分析以及1997年新疆伽师震群高精度定位[J].地震学报,21(3):258—265.ZHOU Shi-yong,XU Zhong-huai,HAN Jing,et al.1999.Analysis on the master event method and precise location of1997Jiashi strong earthquake swarm in western China[J].Acta Seismologica Sinica,21(3):258—265(in Chinese).
    Geiger L.1912.Probability method for the determination of earthquake epicenters from arrival time only[J].Bull StLouis Univ,8:60—71.
    Jackson D D,Matsu'ura M.1985.A Bayesian approach to nonlinear inversion[J].J Geophys Res,90(B1):581—591.
    Lee W H K,Lahr J C.1975.A computer program for determining hypocenter,magnitude,and first motion pattern of local earthquakes[J].U S Geol Surv Open-file Rep,75—311.
    Mooney W D,Laske G,Masters G.1998.A global crustal model at5°x5°[J].J Geophys Re,103:727—747.
    Shen Z K,Jackson D,Ge B.1996.Crustal deformation across and beyond the Los Angeles Basin from geodetic measurements[J].J Geophys Res,101(B12):27957—27980.
    Spence W.1980.Relative epicenter determination using P-wave arrival-time differences[J].Bull Seism Soc Amer,70(1):171—183.
    Takagi A,Hasegawa A,Umino N.1977.Seismic activity in the Northeastern Janpan Arc[J].J Phys Earth,25(Suppl):95—104.
    Waldhauser F,Ellsworth W L.2000.A double-difference earthquake location algorithm:Method and application to theNorthern Hayward Fault,California[J].Bull Seism Soc Amer,90(6):1353—1368.
    Wu Y M,Chang C H,Zhao L,et al.2008.A comprehensive relocation of earthquakes in Taiwan from1991to2005[J].Bull Seism Soc Amer,98(3):1471—1481.

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