2005-2007年四川地震的时空演化特征分析
|
摘要
对2005-2007年四川省内发生的262次地震(震级为3～5级)进行时间-空间分布统计分析,发现这些地震的时空演化具有一定的内在规律。通过对3年来地震数据的可视化分析,发现四川省有4个明显的地震热点地区,而且3年来这4个热点地区的地震发生频率的变化规律不一。基于球面坐标的空间分布统计分析方法,本文分析了地震的空间分布重心、地理范围,发现地震的重心具有明显的变化规律,范围不具有明显的规律性:对逐年的地震数据进分析发现,3年来地震的重心一直在向东南方向移动;将3年的数据综合为4个季度进行分析发现,第1～3季度一直向东南移动,第4季度则突然跳回到西北处;将3年的数据按12个季度进行分析,发现地震重心在前2年的8个季度中具有年周期的逆时针旋转规律,在2007年的前3个季度中,地震的重心仍逆时针旋转,第4个季度出现较大异常,重心往东南方向大跳了一步。最后以5.12汶川震中(30.986°N,103.364°E)为中心,分析了2005-2007年四川地震的空间分布的统计规律曲线,发现2007年地震出现较大的外移趋势,远离汶川地震震中。本文的研究方法和结果可以为地震的预报预测研究提供参考。
Using spatial statistics and data of 262 small earthquakes occurred in Sichuan province between 2005 and 2007, this paper has identified some statistical patterns in the spatiotemporal evolution of these small earthquakes.Four earthquake hotspots are obvious from the map visualization of earthquakes between 2005 and 2007,and the variations of counts of each earthquake hotspots are very different among themselves.Based on the spherical coordinate system,this paper uses a kind of spatial statistics-global spatial statistics,that is,about the center of gravity,geographical range and so on.Clear variation patterns of the center of gravity of earthquakes are identified.The center of gravity of these small earthquakes moves southeastward from 2005 to 2007; in quarterly grouping,the center of gravity moves southeastward from the first to the third quarter but shifts northwestward in the fourth quarter;the center of gravity moves counterclockwise during a period of 11 quarters,from the first quarter of 2005 to the third quarter of 2007,but shifts greatly clockwise southeast in the last quarter 2007.This paper also examines the spatiotemporal distribution of these small earthquakes with reference to their center of gravity and the epicenter of the Wenchuan Earthquake and discusses the relationship between these small earthquakes and the Wenchuan Earthquake.It is shown that,during 2007,small earthquakes are in a trend of moving outward from Wenchuan Earthquake,unlike the small earthquakes in 2005 and 2006.
Using spatial statistics and data of 262 small earthquakes occurred in Sichuan province between 2005 and 2007, this paper has identified some statistical patterns in the spatiotemporal evolution of these small earthquakes.Four earthquake hotspots are obvious from the map visualization of earthquakes between 2005 and 2007,and the variations of counts of each earthquake hotspots are very different among themselves.Based on the spherical coordinate system,this paper uses a kind of spatial statistics-global spatial statistics,that is,about the center of gravity,geographical range and so on.Clear variation patterns of the center of gravity of earthquakes are identified.The center of gravity of these small earthquakes moves southeastward from 2005 to 2007; in quarterly grouping,the center of gravity moves southeastward from the first to the third quarter but shifts northwestward in the fourth quarter;the center of gravity moves counterclockwise during a period of 11 quarters,from the first quarter of 2005 to the third quarter of 2007,but shifts greatly clockwise southeast in the last quarter 2007.This paper also examines the spatiotemporal distribution of these small earthquakes with reference to their center of gravity and the epicenter of the Wenchuan Earthquake and discusses the relationship between these small earthquakes and the Wenchuan Earthquake.It is shown that,during 2007,small earthquakes are in a trend of moving outward from Wenchuan Earthquake,unlike the small earthquakes in 2005 and 2006.
引文
[1]马宗晋.20世纪地震预报科学的回顾与展望[J].国际地震动态,2000(6):1-4.Ma Zongjin.Recent Developments in World Seismology,2000(6):1-4.
[2]Kafka A L,Levin S Z.Does the spatial distribution of smaller earthquakes delineate areas where larger earthquakes are likely to occur?[J].Bulletin of the Seismological Society of American,2000,90(3):724-738.
[3]薛艳,梅世蓉.唐山大震前后一般震群与前兆震群时空演化特征研究[J].地震,1999,19(2):78-84.Xue Yan,Mei Shirong.Earthquake,1999,19(2):78-84.
[4]于泳,洪汉净,刘培洵,等.全球大地震时空分布与动力学机制的初步研究[J].地学前缘,2003,10(1):5-10.Yu Yong,Hong Hanjing,Liu Peixun,et al.Earth Science Frontiers,2003,10(1):5-10.
[5]盛菊琴,赵卫明,马禾青,等.地震时、空分布均匀度研究探讨[J].地震,2004,24(2):47-52.Sheng Juqin,Zhao Weiming,Ma Heqing,et al.Earthquake,2004,24(2):47-52.
[6]安镇文,杨翠华.地震时空丛集的多重分形研究[J].地球物理学报,2000,43(1):74-80.An Zhenwen,Yang Cuihua.Chinese Journal of Geophysics,2000,43(1):74-80.
[7]马瑾,马胜利.地震前异常的阶段性及其空间分布特征[J].地震地质,1995,17(4):363-371.Ma Jin,Ma Shengli.Seismology and Geology,1995,17(4):363-371.
[8]雷建成,张耀国,等.地震空间分布函数的确定方法研究[J].中国地震,1997,13(1):65-73.Lei Jiancheng,Zhang Yaoguo,et al.Earthquake Research in China,1997,13(1):65-73.
[9]吴立新,刘善军,陈云浩,等.汶川地震前卫星热红外异常与云异常现象[J].科技导报,2008,26(10):32-36.Wu Lixin,Liu Shanjun,Chen Yunhao,et al.Science and Technology Review,2008,26(10):32-36.
[10]赵作权.空间分布统计:对统计学的挑战,统计学评论[J].2008(4),待出版.Zhao Zuoquan.Spatial statistics:A challenge for traditional statistics,review of statistics[J].2008(4),in press.
[11]同济大学数学教研室.高等数学(上、下册)[M].4版.北京:高等教育出版社,2000.Tongji Mathematical Education Lab.Advanced Mathematics(vol1,2)[M].4th ed.Beijign:Higher Education Press,2000.
[12]徐阳,杨兴云.空间解析几何及其应用[M].哈尔滨:哈尔滨工业大学出版社,2006.Xu Yang,Yang Xingyun.Spatial analytic geometry and its applications[M].Harbin:Harbin Institute of Technology Press,2006.
[13]韩渭宾.四川地震工作三十年的进展与新世纪的展望[J].四川地震,2001(1):1-8.Han Weibin.Earthquake Research in Sichuan,2001(1):1-8.
[2]Kafka A L,Levin S Z.Does the spatial distribution of smaller earthquakes delineate areas where larger earthquakes are likely to occur?[J].Bulletin of the Seismological Society of American,2000,90(3):724-738.
[3]薛艳,梅世蓉.唐山大震前后一般震群与前兆震群时空演化特征研究[J].地震,1999,19(2):78-84.Xue Yan,Mei Shirong.Earthquake,1999,19(2):78-84.
[4]于泳,洪汉净,刘培洵,等.全球大地震时空分布与动力学机制的初步研究[J].地学前缘,2003,10(1):5-10.Yu Yong,Hong Hanjing,Liu Peixun,et al.Earth Science Frontiers,2003,10(1):5-10.
[5]盛菊琴,赵卫明,马禾青,等.地震时、空分布均匀度研究探讨[J].地震,2004,24(2):47-52.Sheng Juqin,Zhao Weiming,Ma Heqing,et al.Earthquake,2004,24(2):47-52.
[6]安镇文,杨翠华.地震时空丛集的多重分形研究[J].地球物理学报,2000,43(1):74-80.An Zhenwen,Yang Cuihua.Chinese Journal of Geophysics,2000,43(1):74-80.
[7]马瑾,马胜利.地震前异常的阶段性及其空间分布特征[J].地震地质,1995,17(4):363-371.Ma Jin,Ma Shengli.Seismology and Geology,1995,17(4):363-371.
[8]雷建成,张耀国,等.地震空间分布函数的确定方法研究[J].中国地震,1997,13(1):65-73.Lei Jiancheng,Zhang Yaoguo,et al.Earthquake Research in China,1997,13(1):65-73.
[9]吴立新,刘善军,陈云浩,等.汶川地震前卫星热红外异常与云异常现象[J].科技导报,2008,26(10):32-36.Wu Lixin,Liu Shanjun,Chen Yunhao,et al.Science and Technology Review,2008,26(10):32-36.
[10]赵作权.空间分布统计:对统计学的挑战,统计学评论[J].2008(4),待出版.Zhao Zuoquan.Spatial statistics:A challenge for traditional statistics,review of statistics[J].2008(4),in press.
[11]同济大学数学教研室.高等数学(上、下册)[M].4版.北京:高等教育出版社,2000.Tongji Mathematical Education Lab.Advanced Mathematics(vol1,2)[M].4th ed.Beijign:Higher Education Press,2000.
[12]徐阳,杨兴云.空间解析几何及其应用[M].哈尔滨:哈尔滨工业大学出版社,2006.Xu Yang,Yang Xingyun.Spatial analytic geometry and its applications[M].Harbin:Harbin Institute of Technology Press,2006.
[13]韩渭宾.四川地震工作三十年的进展与新世纪的展望[J].四川地震,2001(1):1-8.Han Weibin.Earthquake Research in Sichuan,2001(1):1-8.
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