华东三分区波速比时空特征分析与研究
详细信息 本馆镜像全文    |  推荐本文 | | 获取馆网全文
摘要
对华东三个活动地块区进行了波速比时空对比分析,发现:各活动块区的波速比曲线随时间变化形态差异较大,目前仅鲁东黄海块体处于波速低值异常,但是异常幅度比较小,短期内发生中强地震的可能性不大;空间分布上主要以低值异常为主,近三年的波速比低值异常主要集中在山东南部地区。同时结合安庆MS4.8、高邮MS4.9等震例,在震前高值区会明显出现大范围离散-收敛(发震)-离散现象。
Zhang Guomin et al.(2005)presented the Chinese active block division research results,analyzing the regional characteristics of East China seismic geology and seismic activity on three plots.(Comparing seismic wave velocity space and time,we can see that each earthquake block's seismic wave velocity curve changes with time differences.In the eastern part of Shandong Province and in the Yellow Sea seismic block,recent seismic velocity shows low-value anomalies,but the abnormal amplitude is relatively small,and therefore the possibility of moderately strong earthquakes occurring in the short term is small.East China seismic wave velocity distribution in space is connected to low-value anomalies;in nearly three years of seismic wave velocity spatial distribution,East China Earthquake low velocity ratio anomalies were mainly concentrated in southern Shandong Province.Analyzing this together with the Anqing MS4.8and Gaoyou MS4.9earthquake characteristics,a high-value area before an earthquake will show a significantly large scope of discrete convergence phenomena.The East China area,which spans the three tectonic units North China,Southern China,and Yellow Sea,has a complex geologic structure.The regional deep fault has an obvious effect on the regional tectonic movement and strong earthquake activity and distribution.The Tancheng-Lu-jiang(Tan-Lu)fault zone,agreat fault across the East China area,spawned the Jiangxi region's2005Jiujiang-Ruichang MS5.7earthquake,as well as the Dingyuan MS4.2,Anqing MS4.8,Ruichang-Yangxin MS4.9,and Gaoyou MS4.6earthquakes.In this fault belt,the intensity and frequency of moderate seismic activity is significantly increased.Studying the East China region,especially the ratio of wave velocity features near the area of the Tan-Lu fault zone,can give a scientific basis for the seismic trend in the region,enhance the use value of seismic station information,and realize the organic combination of earthquake monitoring and prediction.This study uses the China Earthquake Networks Center earthquake catalog data for the East China area(27°~38°latitude,111°~125°longitude)to calculate that,for a Richter magnitude where ML≥1,there were 2 815 events from January 2008 to September 2013,with a seismic wave velocity ratio of 1834.According to the East China region's boundary and tectonic characteristics,the study area is divided into the North China,Southern China,and the Eastern-Yellow Sea blocks(Figure 1)to study and analyze the data.As Figure 1shows,the distribution of earthquakes is relatively uniform,and the area of earthquake monitoring station density is high,so that the spatial and temporal characteristics of wave velocity ratio representing the region calculate the wave velocity ratio very well.
引文
[1]Birch F.The Velocity of Compressional Wave in Rocks to 10Kilobars[J].J Geophys Res,1960,65:1083-1102.
    [2]Simmons G.Velocity of Shear Wave in Rocks to 10Kilobars[J].J Geophys Res,1964,69:1123-1130.
    [3]NUR A Dilatoncy.Pore Fluid and Premonitory Varations of tS/tP,Travel Times[J].BSSA,1972,62(5):2322-2330.
    [4]Scholz C H,Sykes L R.Aggarwol Y P.Earthquake Prediction:Aphysical Basis[J].Science,1973,181(4):102.
    [5]冯德益.地震波速异常[M].北京:地震出版社,1981.FENG De-yi.Anomalies of Seismic Velocity[M].Beijing:Seismological Press,1981.(in Chinese)
    [6]梅世蓉,冯德益,张国民,等.中国地震预报概论[M].北京:地震出版社,1993:78-80.MEI Shi-rong,FENG De-yi,ZHANG Guo-ming,et al.Introduction to Earthquake Prediction China[M].Beijing:Seismological Press,1993:78-80.(in Chinese)
    [7]傅淑芳.地震学教程(下)[M].北京:地震出版社,1980.264-270.FU Shu-fang.Seismology Tutorial(Lower)[M].Beijing:Seismological Press,1980:264-270.(in Chinese)
    [8]徐果明,周惠兰.地震学原理[M].北京:科学出版社,1982:426-427.XU Guo-ming,ZHOU Hui-lan.Seismology Theory[M].Beijing:Science Press,1982:426-427.(in Chinese)
    [9]陆远忠,陈章立.地震预报的地震学方法[M].北京:地震出版社,1985.LU Yuan-zhong,CHEN Zhang-li.Seismic Method for Earthquake Prediction[M].Beijing:Seismological Press,1985.(in Chinese)
    [10]徐鑫,刘东旺,刘泽民.安徽及邻区中强震前波速比变化研究[J].华北地震科学,2013,31(1):16-19.XU Xin,LIU Dong-wang,LIU Ze-min.Stud on Seismic Velocity Ratio Changing before Moderate-Strong Earthquake in Anhui Province and Its Surrounding Area[J].North China Earthquake Sciences,2013,31(1):16-19.(in Chinese)
    [11]黎明晓,刘杰.云南地区地震序列的波速比(VP/VS)异常的研究[J].地震,2006,26(1):26-34.LI Ming-xiao,LIU Jie.Study on Velocity Ratio(VP/VS)Anomaly of Earth-Quake Sequences in Yunnan Region[J].Earthquake,2006,24(1):26-34.(in Chinese)
    [12]张小涛,吕坚,马广庆,等.九江—瑞昌地震序列的波速比特征研究[J].华北地震科学,2006,24(4):36-40.ZHANG Xiao-tao,LV Jian,MA Guang-qing,et al.Characteristics of VP/VS Ratio in the Series of Jiujiang-Ruichang Earthquake[J].North China Earthquake Sciences,2006,24(4):36-40.(in Chinese)
    [13]张博,冯建刚,张辉,等.甘肃岷县漳县MS6.6地震序列波速比变化特征研究[J].地震工程学报,2013,35(3):557-561.ZHANG Bo,FENG Jian-gang,ZHANG Hui,et al.Study on Wave Velocity Ratio(VP/VS)Varia Tion Characteristics of Minxian-Zhangxian MS6.6 Earthquake Sequence,Gansu Province[J].China Earthguake Engineering Journal,2013,35(3):557-561.(in Chinese)
    [14]王林瑛,李艳娥,李芳,等.汶川地震前后地震波速比和视速度变化特征的研究[J].地震学报,2011,33(1):1-14.WANG Lin-ying,LI Yan-e,LI Fang,et al.Temporal Variation of Vp/Vs,Vp and Vs before and after 2008 Wenchuan Earthquake[J].Acta Seismologica Sinica,2011,33(1):1-14.(in Chinese)
    [15]冯建刚,代炜,董治平,等.青藏块体东北缘平均波速比的测定及研究[J].西北地震学报,2009,31(1):61-65.FENG Jian-gang,DAI We,DONG Zhi-ping,et al.DetermiNation and Study on Average Seismic Velocity Ratio(Vp/Vs)in Northeastern Margin of Qinghai-Tibet Block[J].Northwestern Seismological Journal,2009,31(1):61-65.(in Chinese)
    [16]张小涛,韩丽萍,张新东,等.河北邯郸—邢台地区波速比和泊松比分布特征研究[J].西北地震学报,2012,34(1):84-87.ZHANG Xiao-tao,HAN Li-ping,ZHANG Xin-dong,et al.Distribution Characteristics of Wave Velocity Ratio and Poisson’s Ratio in Handan-Xingtai Areas,Hebei Province[J].Northwestern Seismological Journal,2012,34(1):84-87.(in Chinese)
    [17]李发,李罡风,张佑龙,等.安庆4.8级地震的余震S波分裂研究[J].华南地震,2012,32(1):28-34.Li Fa,LI Gang-feng,ZHANG You-long,et al.Study on Shear Wave Splitting of Aftershocks of M4.8 Anqing Earthquake[J].South China Journal of Seismology,2012,32(1):28-34.(in Chinese)

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