汶川M_S8.0级地震余震重新定位及其空间分布特征研究
|
摘要
对由四川台网提供的2008年5月12日至2008年12月31日期间发生的地震观测报告资料进行了整理,并根据研究需要从中挑选出了2957次地震事件用于地震定位研究。然后,采用双差定位方法对汶川M_s8.0级地震及挑选出的余震进行了重新定位,得到2678个地震的震源位置,重新定位后走时均方根残差由重新定位前的1.01s降到了0.20s,水平和垂直方向标准差分别为±0.85km和±1.3km。余震震中沿走向分布的总长度约为350km,震源深度优势分布为5～20km,平均震源深度为11.4km。文章结合地表考察破裂、震源机制解等研究结果,对余震空间分布进行了更为详细的分段和讨论,提出以下3点认识:1)余震震中沿主破裂带表现出明显的空间分段活动特征,根据余震空间分布特征和震源机制解可推测断层运动方式由一开始的逆冲为主,经过渡段最终转换为以右旋走滑为主;2)沿小鱼洞-棉篪-理县和青川-文县方向延伸的北西向余震带存在两个与龙门山构造带走向近似垂直的捩断层;3)龙门山构造带的北段(水观乡以北),存在一个斜跨北川-映秀断裂和青川-平武断裂的隐伏断层,并且该隐伏断层参与了北段余震的发震过程。
In this paper,the observation data reports of earthquakes occurred during the period of May 12,2008 to December 31,2008,provided by Sichuan seismic networks,were dealt with and 2957 earthquake events were selected to be used for earthquake location research according to the demand of the research.Then,the Wenchuan M_S8.0 earthquake and its 2957 aftershocks were relocated using the double difference algorithm.As a result,the root-mean-square residual error of the travel time of the selected earthquakes reduced from 1.01s before relocation to 0.20s after relocation and the horizontal and vertical standard errors of 2678 relocated hypocenters are±0.85km and±1.3km,respectively.The total spatial distribution length of aftershock epicenters is about 350km and the predominance distribution of focal depth is 5～20km,with the average depth of 11.4km.Finally,three conclusions as follows can be obtained :(1)the epicenters of aftershocks exhibit obvious spatial segmentation characteristic along main rupture zones,but according to the focal depth distribution of aftershocks and the focal mechanism solutions,it can be inferred that the fault movement be dominated by thrust at the beginning and then turned into right-lateral strike-slip;(2)there probably are two north-west tear faults which extend along Xiaoyudong-Mianchi-Lixian and Qingchuan-Wenxian,respectively and areapproximately vertical to the Longmenshan tectonic belt;(3)and so it can be inferred that this blind fault participated in the occurrence process of aftershocks in the north section.
In this paper,the observation data reports of earthquakes occurred during the period of May 12,2008 to December 31,2008,provided by Sichuan seismic networks,were dealt with and 2957 earthquake events were selected to be used for earthquake location research according to the demand of the research.Then,the Wenchuan M_S8.0 earthquake and its 2957 aftershocks were relocated using the double difference algorithm.As a result,the root-mean-square residual error of the travel time of the selected earthquakes reduced from 1.01s before relocation to 0.20s after relocation and the horizontal and vertical standard errors of 2678 relocated hypocenters are±0.85km and±1.3km,respectively.The total spatial distribution length of aftershock epicenters is about 350km and the predominance distribution of focal depth is 5～20km,with the average depth of 11.4km.Finally,three conclusions as follows can be obtained :(1)the epicenters of aftershocks exhibit obvious spatial segmentation characteristic along main rupture zones,but according to the focal depth distribution of aftershocks and the focal mechanism solutions,it can be inferred that the fault movement be dominated by thrust at the beginning and then turned into right-lateral strike-slip;(2)there probably are two north-west tear faults which extend along Xiaoyudong-Mianchi-Lixian and Qingchuan-Wenxian,respectively and areapproximately vertical to the Longmenshan tectonic belt;(3)and so it can be inferred that this blind fault participated in the occurrence process of aftershocks in the north section.
引文
1 曹俊兴,刘树根.对四川汶川大地震有关问题的思考和识.成都理工大学学报(自然科学版),2008,35(4) :414 Cao Junxing,Liu Shugen.The Wenchuan earthquake and thoughts on relavant issues.Journal of Chengdu University of Technology (Science & Technology Edition),2008,35 (4) :414-425
2 张培震,徐锡伟,闻学泽等.2008年汶川8． 0级地震发震断裂的滑动速率、复发周期和构造成因.地球物理学报,2008,51(4) :1066-1073 Zhang Peizhen,Xu Xiwei,Wen Xueze et al.Slip rates and recurrence intervals of Longmen Shan active fault zone,and tectonic implications for the mechanism of the May 12 Wenchuan eartquake,2008,Sichuan,China.Chinese Journal of Geoghysics,2008,51 (4) :1066-1073
3 马保起,张世民,田勤俭等.汶川8． 0级地震地表破裂带.第四纪研究,2008,28(4) :513-517 Ma Baoqi,Zhang Shimin,Tian Qinjian et al.The surface rupture of the Wenchuan Earthquake(M_S8． 0) .Quaternary Sciences,2008,28(4) :513-517
4 何仲太,马保起,田勤俭等.汶川8． 0级地震地表破裂平通镇段的变形特征.第四纪研究,2008,28(5) :789-795 He Zhongtai,Ma Baoqi,Tian Qinjian et al.Deformation features of surface rupture of the Wenchuan Earthquake (M_S8． 0) at the Pingtong town.Quaternary Sciences,2008,28 (5) :789-795
5 陈九辉,刘启元,李顺成等.汶川M_S8． 0地震余震序列重新定位及其地震构造研究地球物理学报学,2009,52(2) :390-397 Chen Jiuhui,Liu Qiyuan,Li Shuncheng et al.Seismotectonic study by relocation of the Wenchuan M_S8． 0 earthquake sequence.Chinese Journal of Geophysics,2009,52 (2) :390-397
6 李延兴,张静华,周伟等.汶川M_S8． 0地震孕育发生的机制与动力学问题.地球物理学报,2009,52(2) :519-530 Li Yanxing,Zhang Jinghua,Zhou Wei et al.The mechanism and dynamics of the generation and occurrence for Wenchuan M_S8． 0 earthquake.Chinese Journal of Geophysics,2009,52 (2) :519-530
7 胡幸平,俞春泉,陶开等.利用P波初动资料求解汶川地震及其强余震震源机制解.地球物理学报,2008,51(6) 1711-1718 Hu Xingping,Yu Chunquan,Tao Kai et al.Focal mechanism solutions of Wecnhuan earthquake and its strong aftershocks obtained from initial P wave polarity analysis.Chinese Journal of Geophysics,2008,51(6) :1711-1718
8 郑勇,马宏生,吕坚等.汶川地震强余震(Ms≥5． 6) 的震源机制解及其与发震构造的关系.中国科学(D辑),2009,39(4) :413-426 Zheng Yong,Ma Hongsheng,Lu Jian et al.Focal mechanism solutions of Wecnhuan earthquake and its strong aftershocks (Ms≥ 5． 6) and its relationship to seismotectonic.Science in China (Series D),2009,39(4) :413-426
9 王勤彩,陈章立,郑斯华.汶川大地震余震序列震源机制的空间分段特征.科学通报,2009,54(16) :2348-2354 Wang Qincai,Chen Zhangli,Zheng Sihua.Spatial segmentation characteristic of focal mechanism of aftershock sequence of Wenchuan Earthquake.Chinese Science Bulletin,2009,54 (13) :2263-2270
10 徐锡伟,闻学泽,叶建青等.汶川M_S8． 0地震地表破裂带及其发震构造.地震地质,2008,30(3) :597-629 Xu Xiwei,Wen Xueze,Ye Jianqing et al.The M_S8． 0 Wenchuan earthquake surface ruptures and its seismogenic structure.Seismology and Geology,2008,30 (3) :597-629
11 李勇,黄润秋,Densmore A L等.龙门山小鱼洞破裂在汶川地震中的地表破裂及地质意义.第四纪研究,2009,29(3) :502-512 Li Yong,Huang Runqiu,Densmore A L et al.Surface rupture of Xiaoyundong Fault caused by Wenchuan Earthquake and its geological significance.Quaternary Sciences,2009,29 (3) :502-512
12 李勇,黄润秋,周荣军等.龙门山地震带的地质背景与汶川地震的地表破裂.工程地质学报,2009,17(1) 3-17 Li Yong,Huang Runqiu,Zhou Rongjun et al.Geological background of Longmen Shan seismic belt and surface ruptures in Wenchuan earthquake.Journal of Engineering Geology,2009,17 (1) 3-17
13 李勇,黄润秋,Densmore A L等.龙门山彭县-灌县断裂的活动构造与地表破裂.第四纪研究,2009,29(3) :403-415 Li Yong,Huang Runqiu,Densmore A L et al.Active tectonics and surface rupture of the Pengxian-Guanxian fault,Longmen Mountain,Sichuan China.Quaternary Sciences,2009,29 (3) :403-415
14 董顺利,李勇,陈龙生等.汶川M_S8． 0地震的地表破裂过程--以都江堰八角庙村断层擦痕剖面为例.第四纪研究,2009,29(3) :439-448 Dong Shunli,Li Yong,Chen Longsheng et al.Surface rupture of Wenchuan M_S8． 0 earthquake based on fault scratch at Bajiaomiao,Dujiangyan.Quaternary Sciences,2009,29 (3) :439-448
15 张勇,冯万鹏,许力生等.2008年汶川大地震的时空破裂过程.中国科学(D辑),2008,38(10) :1186-1194 Zhang Yong,Feng Wanpeng,Xu Lisheng et al.Spatio-temporal rupture process of 2008 great Wenchuan earthquake.Science in China(Series D),2009,52(2) :145-154
16 王卫民,赵连锋,李娟等.四川汶川8． 0级地震震源过程.地球物理学报,2008,51(5) :1403-1410 Wang Weimin,Zhao Lianfeng,Li Juan et al.Rupture process of the M_S8． 0 Wenchuan earthquake of Sichuan,China.Chinese Journal of Geophysics,2008,51 (5) :1403-1410
17 国家重大科学工程"中国地壳运动观测网络"项目组.GPS测定的2008年汶川M_S8． 0级地震的同震位移场.中国科学(D辑),2008,38(10) :1195-1206 The Group of National Important Project on Science " Crustal Movement Observation Network of China ".The co-seismic displacement setting of the M_S8． 0 Wenchuan earthquake produced by GPS measurement,2008． Science in China (Series D),2008,39(10) :1195-1206
18 陈立春,冉永康,陈杰等.龙门山前山断裂大地震原地重复发生的地质地貌证据.第四纪研究,2009,29(3) :472-483 Chen Lichun,Ran Yongkang,Chen Jie et al.Geological and geomorphic evidence for repeatedly occurring severe earthquakes on fronter-range fault of Longmenshan,China.Quaternary Sciences,2009,29(3) :472-483
19 张世民,谢富仁,黄忠贤等.龙门山地区上地壳的拱曲冲断作用及其深部动力学机制探讨.第四纪研究,2009,29(3) :449-463 Zhang Shimin,Xie Furen,Huang Zhongxian et al.Bending and thrusting of the upper crust in Longmenshan area and its deep dynamics.Quaternary Sciences,2009,29(3) :449-463
20 李海兵,司家亮,付小方等.2008年汶川地震同震滑移特征、最大滑移量及构造意义.第四纪研究,2009,29(3) :387-402 Li Haibing,Si Jialiang,Fu Xiaofang et al.Co-seismic rupture and maximum displacement of the 2008 Wenchuan earthquake and its tectonic implications.Quaternary Sciences,2009,29 (3) :387-402
21 黄媛,吴建平,张天中等.汶川8． 0级大地震及其余震序列重定位研究.中国科学(D辑),2008,38(10) :1242-1249 Huang Yuan,Wu Jianping,Zhang Tianzhong et al.Relocation of the M_S8． 0 Wenchuan earthquake and its aftershock sequence.Science in China(Series D),2008,51 (12) :1703-1712
22 朱艾斓,徐锡伟,刁桂苓等.汶川M_S8． 0地震部分余震重新定位及地震构造初步分析.地震地质,2008,30(3) :760-767 Zhu Ailan,Xu Xiwei,Diao Guiling et al.Relocation of the M_S8． 0 Wenehuan earthquake sequence in part:Preliminary seismotectonic analysis.Seismology and Geology,2008,30 (3) :759-767
23 吕坚,苏金蓉,靳玉科等.汶川8． 0级地震序列重新定位及其发震构造初探.地震地质,2008,30(4) :918-925 Lu Jian,Su Jinrong.Jin Yuke et al.Discussion on relocation and seismo-tectonics of the M_S8． 0 Wenchuan earthquake sequences.Seismology and Geology,2008,30 (4) :918-925
24 Waldhauser F,Ellsworth W L.A double-difference earthquake location algorithm:Method and application to the Northern Hayward Fault,California.Bulletin of the Seismological Society America,2000,90(6) :1353-1368
25 Waldhauser F,Ellsworth W L.Fault structure and mechanics of the Hayward Fault,California,from double-difference earthquake locations.Journal of Geophysical Research,2002,107 (B3) :2054,doi:10． 1029/2000JB000084
26 黄媛,杨建思,张天中.2003年新疆巴楚一伽师地震序列的双差法重新定位研究.地球物理学报,2006,49(1) :162-169 Huang Yuan,Yang Jiansi,Zhang Tianzhong.Relocation of the Bachu-Jiashi,Xinjiang earthquake sequence in 2003 using the double-difference location algorithm.Chinese Journal of Geophyscis,2006,49(1) :162-169
27 赵珠,范军,郑斯华等.龙门山断裂带地壳速度结构和震源位置的精确修定,地震学报,1997,19(6) :615-622 Zhao Zhu,Fan Jun,Zheng Sihua et al.Precision determination of the crustal structure and hypo central locations in the Longmenshan thrust nappe belt.Acta Seismological Sinica,1997,19 (6) :615-622
2 张培震,徐锡伟,闻学泽等.2008年汶川8． 0级地震发震断裂的滑动速率、复发周期和构造成因.地球物理学报,2008,51(4) :1066-1073 Zhang Peizhen,Xu Xiwei,Wen Xueze et al.Slip rates and recurrence intervals of Longmen Shan active fault zone,and tectonic implications for the mechanism of the May 12 Wenchuan eartquake,2008,Sichuan,China.Chinese Journal of Geoghysics,2008,51 (4) :1066-1073
3 马保起,张世民,田勤俭等.汶川8． 0级地震地表破裂带.第四纪研究,2008,28(4) :513-517 Ma Baoqi,Zhang Shimin,Tian Qinjian et al.The surface rupture of the Wenchuan Earthquake(M_S8． 0) .Quaternary Sciences,2008,28(4) :513-517
4 何仲太,马保起,田勤俭等.汶川8． 0级地震地表破裂平通镇段的变形特征.第四纪研究,2008,28(5) :789-795 He Zhongtai,Ma Baoqi,Tian Qinjian et al.Deformation features of surface rupture of the Wenchuan Earthquake (M_S8． 0) at the Pingtong town.Quaternary Sciences,2008,28 (5) :789-795
5 陈九辉,刘启元,李顺成等.汶川M_S8． 0地震余震序列重新定位及其地震构造研究地球物理学报学,2009,52(2) :390-397 Chen Jiuhui,Liu Qiyuan,Li Shuncheng et al.Seismotectonic study by relocation of the Wenchuan M_S8． 0 earthquake sequence.Chinese Journal of Geophysics,2009,52 (2) :390-397
6 李延兴,张静华,周伟等.汶川M_S8． 0地震孕育发生的机制与动力学问题.地球物理学报,2009,52(2) :519-530 Li Yanxing,Zhang Jinghua,Zhou Wei et al.The mechanism and dynamics of the generation and occurrence for Wenchuan M_S8． 0 earthquake.Chinese Journal of Geophysics,2009,52 (2) :519-530
7 胡幸平,俞春泉,陶开等.利用P波初动资料求解汶川地震及其强余震震源机制解.地球物理学报,2008,51(6) 1711-1718 Hu Xingping,Yu Chunquan,Tao Kai et al.Focal mechanism solutions of Wecnhuan earthquake and its strong aftershocks obtained from initial P wave polarity analysis.Chinese Journal of Geophysics,2008,51(6) :1711-1718
8 郑勇,马宏生,吕坚等.汶川地震强余震(Ms≥5． 6) 的震源机制解及其与发震构造的关系.中国科学(D辑),2009,39(4) :413-426 Zheng Yong,Ma Hongsheng,Lu Jian et al.Focal mechanism solutions of Wecnhuan earthquake and its strong aftershocks (Ms≥ 5． 6) and its relationship to seismotectonic.Science in China (Series D),2009,39(4) :413-426
9 王勤彩,陈章立,郑斯华.汶川大地震余震序列震源机制的空间分段特征.科学通报,2009,54(16) :2348-2354 Wang Qincai,Chen Zhangli,Zheng Sihua.Spatial segmentation characteristic of focal mechanism of aftershock sequence of Wenchuan Earthquake.Chinese Science Bulletin,2009,54 (13) :2263-2270
10 徐锡伟,闻学泽,叶建青等.汶川M_S8． 0地震地表破裂带及其发震构造.地震地质,2008,30(3) :597-629 Xu Xiwei,Wen Xueze,Ye Jianqing et al.The M_S8． 0 Wenchuan earthquake surface ruptures and its seismogenic structure.Seismology and Geology,2008,30 (3) :597-629
11 李勇,黄润秋,Densmore A L等.龙门山小鱼洞破裂在汶川地震中的地表破裂及地质意义.第四纪研究,2009,29(3) :502-512 Li Yong,Huang Runqiu,Densmore A L et al.Surface rupture of Xiaoyundong Fault caused by Wenchuan Earthquake and its geological significance.Quaternary Sciences,2009,29 (3) :502-512
12 李勇,黄润秋,周荣军等.龙门山地震带的地质背景与汶川地震的地表破裂.工程地质学报,2009,17(1) 3-17 Li Yong,Huang Runqiu,Zhou Rongjun et al.Geological background of Longmen Shan seismic belt and surface ruptures in Wenchuan earthquake.Journal of Engineering Geology,2009,17 (1) 3-17
13 李勇,黄润秋,Densmore A L等.龙门山彭县-灌县断裂的活动构造与地表破裂.第四纪研究,2009,29(3) :403-415 Li Yong,Huang Runqiu,Densmore A L et al.Active tectonics and surface rupture of the Pengxian-Guanxian fault,Longmen Mountain,Sichuan China.Quaternary Sciences,2009,29 (3) :403-415
14 董顺利,李勇,陈龙生等.汶川M_S8． 0地震的地表破裂过程--以都江堰八角庙村断层擦痕剖面为例.第四纪研究,2009,29(3) :439-448 Dong Shunli,Li Yong,Chen Longsheng et al.Surface rupture of Wenchuan M_S8． 0 earthquake based on fault scratch at Bajiaomiao,Dujiangyan.Quaternary Sciences,2009,29 (3) :439-448
15 张勇,冯万鹏,许力生等.2008年汶川大地震的时空破裂过程.中国科学(D辑),2008,38(10) :1186-1194 Zhang Yong,Feng Wanpeng,Xu Lisheng et al.Spatio-temporal rupture process of 2008 great Wenchuan earthquake.Science in China(Series D),2009,52(2) :145-154
16 王卫民,赵连锋,李娟等.四川汶川8． 0级地震震源过程.地球物理学报,2008,51(5) :1403-1410 Wang Weimin,Zhao Lianfeng,Li Juan et al.Rupture process of the M_S8． 0 Wenchuan earthquake of Sichuan,China.Chinese Journal of Geophysics,2008,51 (5) :1403-1410
17 国家重大科学工程"中国地壳运动观测网络"项目组.GPS测定的2008年汶川M_S8． 0级地震的同震位移场.中国科学(D辑),2008,38(10) :1195-1206 The Group of National Important Project on Science " Crustal Movement Observation Network of China ".The co-seismic displacement setting of the M_S8． 0 Wenchuan earthquake produced by GPS measurement,2008． Science in China (Series D),2008,39(10) :1195-1206
18 陈立春,冉永康,陈杰等.龙门山前山断裂大地震原地重复发生的地质地貌证据.第四纪研究,2009,29(3) :472-483 Chen Lichun,Ran Yongkang,Chen Jie et al.Geological and geomorphic evidence for repeatedly occurring severe earthquakes on fronter-range fault of Longmenshan,China.Quaternary Sciences,2009,29(3) :472-483
19 张世民,谢富仁,黄忠贤等.龙门山地区上地壳的拱曲冲断作用及其深部动力学机制探讨.第四纪研究,2009,29(3) :449-463 Zhang Shimin,Xie Furen,Huang Zhongxian et al.Bending and thrusting of the upper crust in Longmenshan area and its deep dynamics.Quaternary Sciences,2009,29(3) :449-463
20 李海兵,司家亮,付小方等.2008年汶川地震同震滑移特征、最大滑移量及构造意义.第四纪研究,2009,29(3) :387-402 Li Haibing,Si Jialiang,Fu Xiaofang et al.Co-seismic rupture and maximum displacement of the 2008 Wenchuan earthquake and its tectonic implications.Quaternary Sciences,2009,29 (3) :387-402
21 黄媛,吴建平,张天中等.汶川8． 0级大地震及其余震序列重定位研究.中国科学(D辑),2008,38(10) :1242-1249 Huang Yuan,Wu Jianping,Zhang Tianzhong et al.Relocation of the M_S8． 0 Wenchuan earthquake and its aftershock sequence.Science in China(Series D),2008,51 (12) :1703-1712
22 朱艾斓,徐锡伟,刁桂苓等.汶川M_S8． 0地震部分余震重新定位及地震构造初步分析.地震地质,2008,30(3) :760-767 Zhu Ailan,Xu Xiwei,Diao Guiling et al.Relocation of the M_S8． 0 Wenehuan earthquake sequence in part:Preliminary seismotectonic analysis.Seismology and Geology,2008,30 (3) :759-767
23 吕坚,苏金蓉,靳玉科等.汶川8． 0级地震序列重新定位及其发震构造初探.地震地质,2008,30(4) :918-925 Lu Jian,Su Jinrong.Jin Yuke et al.Discussion on relocation and seismo-tectonics of the M_S8． 0 Wenchuan earthquake sequences.Seismology and Geology,2008,30 (4) :918-925
24 Waldhauser F,Ellsworth W L.A double-difference earthquake location algorithm:Method and application to the Northern Hayward Fault,California.Bulletin of the Seismological Society America,2000,90(6) :1353-1368
25 Waldhauser F,Ellsworth W L.Fault structure and mechanics of the Hayward Fault,California,from double-difference earthquake locations.Journal of Geophysical Research,2002,107 (B3) :2054,doi:10． 1029/2000JB000084
26 黄媛,杨建思,张天中.2003年新疆巴楚一伽师地震序列的双差法重新定位研究.地球物理学报,2006,49(1) :162-169 Huang Yuan,Yang Jiansi,Zhang Tianzhong.Relocation of the Bachu-Jiashi,Xinjiang earthquake sequence in 2003 using the double-difference location algorithm.Chinese Journal of Geophyscis,2006,49(1) :162-169
27 赵珠,范军,郑斯华等.龙门山断裂带地壳速度结构和震源位置的精确修定,地震学报,1997,19(6) :615-622 Zhao Zhu,Fan Jun,Zheng Sihua et al.Precision determination of the crustal structure and hypo central locations in the Longmenshan thrust nappe belt.Acta Seismological Sinica,1997,19 (6) :615-622
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