华南地震2025，Vol.45Issue(1)：19-26,8.DOI:10.13512/j.hndz.2025.01.03
锦屏山—小金河断裂带里庄断裂晚更新世活动的探槽剖面证据
Trench Profile Evidence of Late Pleistocene Activity of Lizhuang Fault in Jinpingshan-Xiaojinhe Fault Zone
摘要
Abstract
The NE-trending Yulongxueshan-Jinpingshan-Longmenshan tectonic belt is a geotectonic boundary of class I between the Qiangtang-Sanjiang orogenic system and the Yangtze Block.The southern part of this belt was hit by the 1996 Lijiang MS7.0 earthquake,while the northern part was hit successively by the 2008 Wenchuan MS8.0 earthquake and the 2013 Lushan MS7.0 earthquake.However,earthquakes with M≥6 are not yet recorded in the middle section of this belt.The Jinpingshan-Xiaojinhe fault zone is an important part of the middle section of the Yulongxueshan-Jinpingshan-Longmenshan tectonic belt.Whether it has been active since the Late Quaternary,especially since the Holocene,is the basis for evaluating its subsequent seismic hazards,understanding and discussing the geologic evolution and present activity of the boundary tectonoc belt along the southeastern margin of the Tibetan Plateau.In recent years,with the support of the Sichuan Active Fracture Prospecting Program,1/50 000 active fault mapping has been carried out along the Jinpingshan-Xiaojinhe fault zone,which includes a detailed survey of the geology and geomorphology,geophysical prospecting,and a series of trenching.Then,a large amount of basic data and new evidence have been obtained.The Lizhuang fault is a major branch with relatively strong activity in the Late Quaternary of the Jinpingshan-Xiaojinhe fault zone.On the basis of geological and geomorphological investigations,this paper focuses on the analysis and discussion of four trench profiles and the results of chronological tests.The results reveal that the Lizhuang fault has experienced surface rupturing since the formation of the Yalong River T4 terrace,and its latest faulting is limited to 20-43 ka BP,which is a Late Pleistocene fault.关键词
锦屏山—小金河断裂/里庄断裂/活动断裂/探槽/地震Key words
Jinpingshan-Xiaojinhe fault zone/Lizhuang fault/Active fault/Trench/Earthquake分类
地球科学引用本文复制引用
王洪达,陈立春,王仕海,游水生,杨明文,植田紫,王文超,王度..锦屏山—小金河断裂带里庄断裂晚更新世活动的探槽剖面证据[J].华南地震,2025,45(1):19-26,8.基金项目
第二次青藏高原科学考察研究(2019QZKK0901) （2019QZKK0901）
四川省活断层普查项目——凉山州活断层普查子项目(513420201900050103)联合资助. （513420201900050103）
