2008年3月21日新疆于田7.3级地震发震构造与震前地震活动特征研究
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摘要
2008年3月21日新疆于田发生7.3级地震,打破了中国大陆6年多的7级地震平静,成为我国近期较为显著的一次地震事件。综合分析MS≥4.0余震分布、震区断裂性质以及等震线长轴方向等资料,认为郭扎错断裂是这次地震的发震构造;据Harvard震源机制解分析,这次地震是在近NS向力的作用下,郭扎错断裂发生略带走滑分量的拉张破裂所致。通过地震前震区附近地震活动特征分析发现,于田地震发生在1996年以来新疆南部及邻区7级地震有序分布的空段;震前震区附近有4级地震空区形成,空区持续91个月后发生了2006年9月12日皮山5.8级"信号震",其后1.5年发生于田7.3级地震。
The Yutian M7.3 earthquake on March 21, 2008, Xinjiang broke the quiescence of more than six years for M7.0 earthquake in Chinese Mainland. The analysis of the aftershocks with M_S≥4.0, fault strike direction in seismic region and the long axis of isoseismal shows Gozhaco fault is the seismogenic structure. According to the Harvard focal mechanism, the normal break of Gozhaco fault leads to the Yutian earthquake under the NS direction regional stress. The analysis of the seismic activity before Yutian earthquake shows that the earthquake occurred in the empty area between the belt of M7.0 earthquakes in the southern region of Xinjiang and its adjacent region; there is M_S4.0 seismic gap, and it lasts 91 months. After that, the "signal earthquake" occurred on September 12, 2006 in the seismic gap, 1.5 years prior to the Yutian earthquake.
The Yutian M7.3 earthquake on March 21, 2008, Xinjiang broke the quiescence of more than six years for M7.0 earthquake in Chinese Mainland. The analysis of the aftershocks with M_S≥4.0, fault strike direction in seismic region and the long axis of isoseismal shows Gozhaco fault is the seismogenic structure. According to the Harvard focal mechanism, the normal break of Gozhaco fault leads to the Yutian earthquake under the NS direction regional stress. The analysis of the seismic activity before Yutian earthquake shows that the earthquake occurred in the empty area between the belt of M7.0 earthquakes in the southern region of Xinjiang and its adjacent region; there is M_S4.0 seismic gap, and it lasts 91 months. After that, the "signal earthquake" occurred on September 12, 2006 in the seismic gap, 1.5 years prior to the Yutian earthquake.
引文
①新疆维吾尔自治区地震局,2008,2008年3月21日新疆于田7·3级地震科考报告。
李海兵、J.Van der Woerd、孙知明等,2008,阿尔金断裂带康西瓦段晚第四纪以来的左旋滑移速率及其达地震复发周期探讨,第四纪研究,28(2),197~213。
李海兵、杨经绥、许志琴等,2006,阿尔金断裂带队青藏高原北部生长、隆升的制约,地学前缘,13(4),59~79。
鲁如魁、张国伟、钟华明等,2007,从郭扎错断裂构造特征探讨阿尔金断裂带西延问题,中国地质,34(2),229~239。
陆远忠、陈章立、王碧泉等,1985,地震预报的地震学方法,北京:地震出版社。
陆远忠、沈建文、宋俊高等,1982,孕震空区与逼近地震,地震学报,4(4),327~336。
陆远忠、王炜、沈建文等,1983,孕震空区与逼近地震(续),地震学报,5(2),129~144。
梅世蓉、冯德益、张国民等,1993,中国地震预报概论,北京:地震出版社,49~65。
孙加林、曹井泉,1995,强震前显著地震和逼近地震的震兆特征及判据指标,地震,4(4),315~322。
王俊国、王琳英、吴晓芝等,2004,华北地区强震前的信号震及其预测意义,地震,24(3),51~60。
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,地球物理学报,47(4),654~662。
中国地震台网中心,2008,http://www.csndmc.ac.cn/newweb/more-quickdata.jsp。
Harvard,2008,http://www.globlecmt.org/cfi-bin/globalcmt-cgi-bin/CMT3/FORM?itype=ymd&yr=2008&mo=3&oday=20&jyr=2008&jday=1&ojyr=2008&ojday=1&otype=nd&nday=1&lmw=0&umw=10&lms=0&ums=10&lmb=0&umb=10&llat=-90&ulat=90&llon=-180&ulon=180&lhd=0&uhd=1000<s=-9999&uts=9999&lpe1=0&upe1=90&lpe2=0&upe2=90&list=0.
Liu Puxiong,Huang Deyu,Wang Liping,et al.,1984,Seismicity pattern over the preparatory process of strong earthquakes,ISCSEPBeijing:Seismological Press,China,100~110.
USGS,2008,http://neic.usgs.gov/cgi-bin/sopar/sopar.cgi?GS=1&HRV=2&OTHER=4&FILEFORMAT=1&LMAG=&UMAG=&NDEP1=&NDEP2=&SLAT1=&SLAT2=&SLON1=&SLON2=&SYEAR=2008&SMONTH=03&SDAY=20&EYEAR=2008&EMONTH=03&EDAY=20&SUBMIT=Submit+Search.
李海兵、J.Van der Woerd、孙知明等,2008,阿尔金断裂带康西瓦段晚第四纪以来的左旋滑移速率及其达地震复发周期探讨,第四纪研究,28(2),197~213。
李海兵、杨经绥、许志琴等,2006,阿尔金断裂带队青藏高原北部生长、隆升的制约,地学前缘,13(4),59~79。
鲁如魁、张国伟、钟华明等,2007,从郭扎错断裂构造特征探讨阿尔金断裂带西延问题,中国地质,34(2),229~239。
陆远忠、陈章立、王碧泉等,1985,地震预报的地震学方法,北京:地震出版社。
陆远忠、沈建文、宋俊高等,1982,孕震空区与逼近地震,地震学报,4(4),327~336。
陆远忠、王炜、沈建文等,1983,孕震空区与逼近地震(续),地震学报,5(2),129~144。
梅世蓉、冯德益、张国民等,1993,中国地震预报概论,北京:地震出版社,49~65。
孙加林、曹井泉,1995,强震前显著地震和逼近地震的震兆特征及判据指标,地震,4(4),315~322。
王俊国、王琳英、吴晓芝等,2004,华北地区强震前的信号震及其预测意义,地震,24(3),51~60。
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,地球物理学报,47(4),654~662。
中国地震台网中心,2008,http://www.csndmc.ac.cn/newweb/more-quickdata.jsp。
Harvard,2008,http://www.globlecmt.org/cfi-bin/globalcmt-cgi-bin/CMT3/FORM?itype=ymd&yr=2008&mo=3&oday=20&jyr=2008&jday=1&ojyr=2008&ojday=1&otype=nd&nday=1&lmw=0&umw=10&lms=0&ums=10&lmb=0&umb=10&llat=-90&ulat=90&llon=-180&ulon=180&lhd=0&uhd=1000<s=-9999&uts=9999&lpe1=0&upe1=90&lpe2=0&upe2=90&list=0.
Liu Puxiong,Huang Deyu,Wang Liping,et al.,1984,Seismicity pattern over the preparatory process of strong earthquakes,ISCSEPBeijing:Seismological Press,China,100~110.
USGS,2008,http://neic.usgs.gov/cgi-bin/sopar/sopar.cgi?GS=1&HRV=2&OTHER=4&FILEFORMAT=1&LMAG=&UMAG=&NDEP1=&NDEP2=&SLAT1=&SLAT2=&SLON1=&SLON2=&SYEAR=2008&SMONTH=03&SDAY=20&EYEAR=2008&EMONTH=03&EDAY=20&SUBMIT=Submit+Search.
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