丽江-小金河断裂南、中段地貌特征及构造指示意义  

Geomorphological Features of the South and Middle Sections of Lijiang-Xiaojinhe Fault and Their Tectonic Significance

作　　者：李环宇 丁锐[1,2] 张世民[1] Li Huanyu;Ding Rui;Zhang Shimin(Key Laboratory of Crustal Dynamics,Institute of Crustal Dynamics,China Earthquake Administration,Beying 100085,China;State Key Laboratory of Earthquake Dynamics,Institute of Geolody,China Earthquake Administration,Beijing 100029,China)

机构地区：[1]中国地震局地壳应力研究所,地壳动力学重点实验室,北京100085 [2]中国地震局地质研究所,地震动力学国家重点实验室,北京100029

出　　处：《震灾防御技术》2020年第2期380-391,共12页Technology for Earthquake Disaster Prevention

基　　金：中国地震局地壳应力研究所基本科研业务专项(ZDJ2018-22、ZDJ2017-24);城市活断层探测与地震危险性评价项目:丽江-小金河断裂(丽江盆地隐伏段)地质填图项目、丽江-小金河断裂丽江盆地隐伏段探测;川滇国家地震科学实验场专项:丽江-小金河断裂带晚第四纪活动性鉴定(2018CSES0204)共同资助。

摘　　要：丽江-小金河断裂位于青藏高原东南缘,是川滇菱形块体内重要的次级边界断裂。构造活动对区域河流水系的发育有重要影响,因此,定量研究水系地貌特征可在一定程度上反映区域内构造活动信息。本文采用地形坡度、地形起伏度、面积-高程积分值(HI)等地貌参数研究沿该断裂区域地貌对构造活动的响应。研究发现,断裂北侧坡度和地形起伏度较断裂南侧高,跨断裂4级流域盆地内亚流域盆地面积-高程积分值变化也指示断裂北侧流域成熟度低于断裂南侧,这反映了丽江-小金河断裂存在一定逆冲分量。Lijiang-Xiaojinhe fault is located on the southeastern margin of the Tibet Plateau and is an important secondary boundary fault in the Sichuan-Yunnan rhomboid block. Tectonic activity has an important impact on the development of regional river systems. Therefore, quantitative research on the geomorphological characteristics of river systems can reflect information on tectonic activities in the region. In this paper, topographic gradients, topographic relief, area-elevation integral(HI value) and other geomorphic parameters are used to study the response of the geomorphology along the fault to tectonic activity. The study shows that the slope and terrain relief on the north side of the fault are higher than that on the south side. The extracted small watershed area-elevation integral value shows that the watershed maturity on the north side of the fault is lower than the south side of the fault, which reflects the existence of thrust component of the Lijiang-Xiaojinhe fault.

关 键 词：丽江-小金河断裂 坡度 地形起伏度 面积-高程积分值 构造活动 

分 类 号：P315.2[天文地球—地震学] P548[天文地球—固体地球物理学]