东昆仑断裂带西大滩段晚第四纪古地震历史
|
摘要
对东昆仑断裂带西大滩段进行了断错地貌填图和古地震探槽揭露,共揭露出9次古地震事件,它们的年龄分别为39090±2348aB.P.,27780±2360aB.P.,24100±1451aB.P.,19850±1690aB.P.,12670±714aB.P.,8980±544aB.P.,6380±388aB.P.,4425±265aB.P.和3030±182aB.P.。古地震重复间隔分别为11310±2880a,3680±2211a,4250±1879a,7180±1392a,3690±897a,2600±668a,1955±470a,1395±321a和3030±182a。结果表明,西大滩段晚第四纪古地震活动具有准周期性,其中7次古地震事件发生时间与东昆仑断裂带库赛湖段古地震事件的发生时间非常接近,这意味着东昆仑断裂带库赛湖段和西大滩段既可以独立破裂形成中强地震,也可以同时发生破裂形成强震。东昆仑断裂带的古地震活动历史对于认识该断裂的破裂特征和强震复发规律具有重要的意义。
The East Kunlun fault zone in Northern Tibetan Plateau is a typical active fault zone,characterized by sinistral strike-slip faults.The field investigation indicates that there are a lot of relics along the fault traces of the Xidatan segment,Kunlun fault.The relics include push-up,pull-apart basins,sag pond,and earthquake fault scarps.This implies that the Xidatan segment of Kunlun fault is a seismogenic fault on which surface-rupturing earthquakes often occurred in regular or irregular intervals.To determine the chronology of Late Quaternary surface ruptures of this part of Kunlun fault,three trenches were excavated across the Xidatan segment at Xizangdagou.All sediment samples collected from the trenches were dated by using thermoluminescence(TL)method.Paleoseismic evidence,combined with the thermoluminescence(TL)dating for sediment units from the trenches,show that the Xidatan segment of Kunlun fault has generated at least 9 paleoearthquakes since Late Quaternary,whose ages are 39090±2348aB.P.,27780±2360aB.P.,24100±1451aB.P.,19850±1690aB.P.,12670±714aB.P.,8980±544aB.P.,6380±388aB.P.,4425±265aB.P.,and 3030±182aB.P.,respectively.The recurrence interval between two adjacent events is 11310±2880a,3680±2211a,4250±1879a,7180±1392a,3690±897a,2600±668a,1955±470a,1395±321a,and 3030±182a,respectively.It shows that the rupture behavior and recurrence of great earthquakes along Xidatan segment is similar to those on the Kusai Lake segment of the fault.These results have significant implications for seismic hazard assessment in the East Kunlun fault zone.Although only 9 paleoearthquake events are able to be dated,together with the 9 paleoearthquake events on the Kusai Lake segment of the East Kunlun fault,they can provide more information on major paleoearthquakes occurring along the fault during the Late Quaternary.Combined with the paleoearthquake history on Kusai Lake segment,it is clear that the paleoearthquake rupture on Xidatan segment coexisted with most of those on Kusai Lake segment of the fault.
The East Kunlun fault zone in Northern Tibetan Plateau is a typical active fault zone,characterized by sinistral strike-slip faults.The field investigation indicates that there are a lot of relics along the fault traces of the Xidatan segment,Kunlun fault.The relics include push-up,pull-apart basins,sag pond,and earthquake fault scarps.This implies that the Xidatan segment of Kunlun fault is a seismogenic fault on which surface-rupturing earthquakes often occurred in regular or irregular intervals.To determine the chronology of Late Quaternary surface ruptures of this part of Kunlun fault,three trenches were excavated across the Xidatan segment at Xizangdagou.All sediment samples collected from the trenches were dated by using thermoluminescence(TL)method.Paleoseismic evidence,combined with the thermoluminescence(TL)dating for sediment units from the trenches,show that the Xidatan segment of Kunlun fault has generated at least 9 paleoearthquakes since Late Quaternary,whose ages are 39090±2348aB.P.,27780±2360aB.P.,24100±1451aB.P.,19850±1690aB.P.,12670±714aB.P.,8980±544aB.P.,6380±388aB.P.,4425±265aB.P.,and 3030±182aB.P.,respectively.The recurrence interval between two adjacent events is 11310±2880a,3680±2211a,4250±1879a,7180±1392a,3690±897a,2600±668a,1955±470a,1395±321a,and 3030±182a,respectively.It shows that the rupture behavior and recurrence of great earthquakes along Xidatan segment is similar to those on the Kusai Lake segment of the fault.These results have significant implications for seismic hazard assessment in the East Kunlun fault zone.Although only 9 paleoearthquake events are able to be dated,together with the 9 paleoearthquake events on the Kusai Lake segment of the East Kunlun fault,they can provide more information on major paleoearthquakes occurring along the fault during the Late Quaternary.Combined with the paleoearthquake history on Kusai Lake segment,it is clear that the paleoearthquake rupture on Xidatan segment coexisted with most of those on Kusai Lake segment of the fault.
引文
1 Van der Woerd J,Tapponnier P,Ryerson F Jet al.Uniformpostglacial slip-rate along the central 600km of the Kunlun fault(Tibet),from26Al,10Be and14C dating of riser offsets,and climaticorigin of the regional morphology.Geophysical Journal International,2002,148(3):356~388
2陈杰,陈宇坤,丁国瑜等.2001年昆仑山口西8.1级地震地表破裂带.第四纪研究,2003,23(6):629~639Chen Jie,Chen Yukun,Ding Guoyuet al.Surface rupture zones ofthe 2001 earthquakeMS8.1 west of Kunlun Pass,Northern Qinghai-Xizang Plateau.Quaternary Sciences,2003,23(6):629~639
3徐锡伟,陈文彬,于贵华等.2001年11月14日昆仑山库赛湖地震(MS8.1)地表破裂带的基本特征.地震地质,2002,24(1):1~13Xu Xiwei,Chen Wenbin,Yu Guihuaet al.Characteristic features ofthe surface ruptures of the surface ruptures of the Hoh Sai Hu(Kunlunshan)earthquake(MS8.1)Northern Tibetan Plateau,China.Seismology and Geology,2002,24(1):1~13
4中国地震局.中国昆仑山口西8.1级地震图集.北京:地震出版社,2003.1~105China Seismological Bureau.Album of the Kunlun Pass W.MS8.1Earthquake,China.Beijing:Seismological Press,2003.1~105
5任金卫,汪一朋,吴章明等.青藏高原北部库玛断裂东、西大滩全新世地震形变带及其位移特征和水平滑动率.地震地质,1993,15(3):285~288Ren Jinwei,Wang Yipeng,Wu Zhangminget al.Holoceneearthquake deformation zones and their displacement and slip ratealong the Xidatan-Dongdatan of Kusaihu-Maqu fault in NorthernQinghai-Xizang Plateau.Seismology and Geology,1993,15(3):285~288
6 Van der Woerd J,Ryerson F J,Tapponnier Pet al.Holocene leftslip-rate determined by cosmogenic surface dating on the Xidatansegment of the Kunlun fault(Qinghai,China).Geology,1998,26(8):695~698
7胡道功,赵希涛,尹功明等.昆仑山口羌塘组湖相层的ESR年龄测定.第四纪研究,2004,24(3):366~367Hu Daogong,Zhao Xitao,Yin Gongminget al.ESR Dating of thelacustrine deposits of Qingtang Formation fromthe Kunlun MountainsPass areas.Quaternary Sciences,2004,24(3):366~367
8青海省地震局,中国地震局地壳应力研究所编.东昆仑活动断裂带.北京:地震出版社,1999.1~186Seismological Bureau of Qinghai Province,Institute of CrustalDynamics,China Seismological Bureau eds.Eastern Kunlun ActiveFault Zone.Beijing:Seismological Press,1999.1~186
9胡道功,叶培盛,吴珍汉等.东昆仑断裂带西大滩段全新世古地震研究.第四纪研究,2006,26(6):1012~1020Hu Daogong,Ye Peisheng,Wu Zhenhanet al.Research on Holocenepaleoearthquakes on the Xidatan segment of East Kunlun fault zonein Northern Tibet.Quaternary Sciences,2006,26(6):1012~1020
10田勤俭,丁国瑜.青藏高原北部第四纪早期断裂活动的新生性变化初步研究.第四纪研究,2006,26(1):32~39Tian Qinjian,Ding Guoyu.Preliminary analysis on an EarlyQuaternary new fault trace in North of Tibetan Plateau.QuaternarySciences,2006,26(1):32~39
11任金卫,王敏.GPS观测的2001年昆仑山口西MS8.1级地震地壳变形.第四纪研究,2005,25(1):34~44Ren Jinwei,Wang Min.GPS measured crustal deformation of theMS8.1 Kunlun earthquake on November 14th 2001 in Qinghai-Xizang Plateau.Quaternary Sciences,2005,25(1):34~44
12王峰,王驹,范洪海等.甘肃北山旧井地区晚第四纪活动断裂分布及其构造意义.地质论评,2005,51(3):250~255Wang Feng,Wang Ju,Fan Honghaiet al.Distribution of LateQuaternary active faults and its tectonic significance in the Beishanregion,Gansu Province,China.Geological Review,2005,51(3):250~255
13 Wen Xueze.Assessment of time-dependent seismic hazards onsegments of active fault,and its problem.Chinese Science Bulletin,1998,43(14):1457~1466
14邓起东,汪一鹏,廖玉华等.断层崖崩积楔及贺兰山山前断裂全新世活动历史.科学通报,1984,29(9):557~560Deng Qidong,Wang Yipeng,Liao Yuhuaet al.Colluvial wedge offault scarp and Holocene active history along the Helanshan Mt.Piedmont fault.Chinese Science Bulletin,1984,29(9):557~560
15冉勇康,段瑞涛,邓起东等.海原断裂高湾子地点三维探槽的开挖与古地震研究.地震地质,1997,19(2):97~107Ran Yongkang,Duan Ruitao,Deng Qidonget al.3-D trenchexcavation and paleoseismology at Gaowanzi of the Haiyuan fault.Seismology and Geology,1997,19(2):97~107
16毛凤英,张培震.古地震研究中的逐次限定法与新疆北部主要断裂带的古地震研究.见:《活动断裂研究》编委会,国家地震局地质研究所编.活动断裂研究(4).北京:地震出版社,1995.153~164Mao Fengying,Zhang Peizhen.Method for progressive constraint ofpaleoseismic events and paleoseismological study of major fault zonein Northern Xinjiang.In:Editorial Committee of“Research onActive Fault”,Institute of Geology,State Seismological Bureau eds.Research on Active Fault(4).Beijing:Seismological Press,1995.153~164
17闻学则.活动断裂地震潜势的定量评估.北京:地震出版社,1995.43~50Wen Xueze.Quantitative Estimates of Seismic Potential on ActiveFaults.Beijing:Seismological Press,1995.43~50
18胡道功,吴中海,吴珍汉等.东昆仑断裂带库赛湖段晚第四纪古地震研究.第四纪研究,2007,27(1):27~34Hu Daogong,Wu Zhonghai,Wu Zhenhanet al.Late Quaternarypaleoseismic history on the Kusai Lake segment of East Kunlun faultzone in Northern Tibet.QuaternarySciences,2007,27(1):27~34
2陈杰,陈宇坤,丁国瑜等.2001年昆仑山口西8.1级地震地表破裂带.第四纪研究,2003,23(6):629~639Chen Jie,Chen Yukun,Ding Guoyuet al.Surface rupture zones ofthe 2001 earthquakeMS8.1 west of Kunlun Pass,Northern Qinghai-Xizang Plateau.Quaternary Sciences,2003,23(6):629~639
3徐锡伟,陈文彬,于贵华等.2001年11月14日昆仑山库赛湖地震(MS8.1)地表破裂带的基本特征.地震地质,2002,24(1):1~13Xu Xiwei,Chen Wenbin,Yu Guihuaet al.Characteristic features ofthe surface ruptures of the surface ruptures of the Hoh Sai Hu(Kunlunshan)earthquake(MS8.1)Northern Tibetan Plateau,China.Seismology and Geology,2002,24(1):1~13
4中国地震局.中国昆仑山口西8.1级地震图集.北京:地震出版社,2003.1~105China Seismological Bureau.Album of the Kunlun Pass W.MS8.1Earthquake,China.Beijing:Seismological Press,2003.1~105
5任金卫,汪一朋,吴章明等.青藏高原北部库玛断裂东、西大滩全新世地震形变带及其位移特征和水平滑动率.地震地质,1993,15(3):285~288Ren Jinwei,Wang Yipeng,Wu Zhangminget al.Holoceneearthquake deformation zones and their displacement and slip ratealong the Xidatan-Dongdatan of Kusaihu-Maqu fault in NorthernQinghai-Xizang Plateau.Seismology and Geology,1993,15(3):285~288
6 Van der Woerd J,Ryerson F J,Tapponnier Pet al.Holocene leftslip-rate determined by cosmogenic surface dating on the Xidatansegment of the Kunlun fault(Qinghai,China).Geology,1998,26(8):695~698
7胡道功,赵希涛,尹功明等.昆仑山口羌塘组湖相层的ESR年龄测定.第四纪研究,2004,24(3):366~367Hu Daogong,Zhao Xitao,Yin Gongminget al.ESR Dating of thelacustrine deposits of Qingtang Formation fromthe Kunlun MountainsPass areas.Quaternary Sciences,2004,24(3):366~367
8青海省地震局,中国地震局地壳应力研究所编.东昆仑活动断裂带.北京:地震出版社,1999.1~186Seismological Bureau of Qinghai Province,Institute of CrustalDynamics,China Seismological Bureau eds.Eastern Kunlun ActiveFault Zone.Beijing:Seismological Press,1999.1~186
9胡道功,叶培盛,吴珍汉等.东昆仑断裂带西大滩段全新世古地震研究.第四纪研究,2006,26(6):1012~1020Hu Daogong,Ye Peisheng,Wu Zhenhanet al.Research on Holocenepaleoearthquakes on the Xidatan segment of East Kunlun fault zonein Northern Tibet.Quaternary Sciences,2006,26(6):1012~1020
10田勤俭,丁国瑜.青藏高原北部第四纪早期断裂活动的新生性变化初步研究.第四纪研究,2006,26(1):32~39Tian Qinjian,Ding Guoyu.Preliminary analysis on an EarlyQuaternary new fault trace in North of Tibetan Plateau.QuaternarySciences,2006,26(1):32~39
11任金卫,王敏.GPS观测的2001年昆仑山口西MS8.1级地震地壳变形.第四纪研究,2005,25(1):34~44Ren Jinwei,Wang Min.GPS measured crustal deformation of theMS8.1 Kunlun earthquake on November 14th 2001 in Qinghai-Xizang Plateau.Quaternary Sciences,2005,25(1):34~44
12王峰,王驹,范洪海等.甘肃北山旧井地区晚第四纪活动断裂分布及其构造意义.地质论评,2005,51(3):250~255Wang Feng,Wang Ju,Fan Honghaiet al.Distribution of LateQuaternary active faults and its tectonic significance in the Beishanregion,Gansu Province,China.Geological Review,2005,51(3):250~255
13 Wen Xueze.Assessment of time-dependent seismic hazards onsegments of active fault,and its problem.Chinese Science Bulletin,1998,43(14):1457~1466
14邓起东,汪一鹏,廖玉华等.断层崖崩积楔及贺兰山山前断裂全新世活动历史.科学通报,1984,29(9):557~560Deng Qidong,Wang Yipeng,Liao Yuhuaet al.Colluvial wedge offault scarp and Holocene active history along the Helanshan Mt.Piedmont fault.Chinese Science Bulletin,1984,29(9):557~560
15冉勇康,段瑞涛,邓起东等.海原断裂高湾子地点三维探槽的开挖与古地震研究.地震地质,1997,19(2):97~107Ran Yongkang,Duan Ruitao,Deng Qidonget al.3-D trenchexcavation and paleoseismology at Gaowanzi of the Haiyuan fault.Seismology and Geology,1997,19(2):97~107
16毛凤英,张培震.古地震研究中的逐次限定法与新疆北部主要断裂带的古地震研究.见:《活动断裂研究》编委会,国家地震局地质研究所编.活动断裂研究(4).北京:地震出版社,1995.153~164Mao Fengying,Zhang Peizhen.Method for progressive constraint ofpaleoseismic events and paleoseismological study of major fault zonein Northern Xinjiang.In:Editorial Committee of“Research onActive Fault”,Institute of Geology,State Seismological Bureau eds.Research on Active Fault(4).Beijing:Seismological Press,1995.153~164
17闻学则.活动断裂地震潜势的定量评估.北京:地震出版社,1995.43~50Wen Xueze.Quantitative Estimates of Seismic Potential on ActiveFaults.Beijing:Seismological Press,1995.43~50
18胡道功,吴中海,吴珍汉等.东昆仑断裂带库赛湖段晚第四纪古地震研究.第四纪研究,2007,27(1):27~34Hu Daogong,Wu Zhonghai,Wu Zhenhanet al.Late Quaternarypaleoseismic history on the Kusai Lake segment of East Kunlun faultzone in Northern Tibet.QuaternarySciences,2007,27(1):27~34
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