丽江-小金河断裂全新世滑动速率研究  

Slip Rate of Lijiang-Xiaojinhe Fault in the Holocene

作　　者：郜宇 丁锐[1] 张世民[1] 任俊杰[1] Gao Yu;Ding Rui;Zhang Shimin;Ren Junjie(Institute of Crustal Dynamics,China Earthquake Administration,Beijing 100085,China)

机构地区：[1]中国地震局地壳应力研究所

出　　处：《震灾防御技术》2019年第3期617-627,共11页Technology for Earthquake Disaster Prevention

基　　金：国家自然科学基金（41272234、41572193）;中国地震局地壳应力研究所中央级公益性科研院所基本科研业务专项（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）地质填图和地震行业专项（201108001）共同资助

摘　　要：丽江-小金河断裂与锦屏山断裂共同控制着青藏高原东南边界,研究该断裂的滑动速率有助于理解青藏高原东南缘区域变形模式。本文通过高分辨率遥感影像解译与野外地质调查,发现该断裂错断了一系列河流阶地与洪积扇,且以左旋走滑为主兼具倾滑分量。通过无人机断错地貌测量与碳同位素断代,获得红星-尖山营断裂段全新世左旋走滑速率为(3.32±0.22)mm/a,垂直滑动速率为(0.35±0.02)mm/a;汝南-南溪断裂段北支全新世左旋走滑速率为(2.37±0.20)mm/a。The Lijiang-Xiaojinhe fault jointed with the Jinpingshan fault control the southeastern boundary of the Qinghai-Tibet Plateau. The study on the activity of the Lijiang-Xiaojinhe fault is of great significance for understanding the deformation mode of the southeastern margin of the Qinghai-Tibet Plateau. Interpretation of high-resolution remote sensing images and field geological surveys revealed that the faults have offset a series of river terraces and alluvial fans, with a left-lateral strike-slip and a small amount of tilt-slip. Through the fault geomorphology measurement by UAV and the age determination by carbon isotope dating, we estimated that the left-lateral strike-slip rate of in the Hongxing-Jianshanying fault segment since the Holocene is about 3.32±0.22 mm/a, and the vertical slip rate is about 0.35±0.02 mm/a, and the left-lateral strike-slip rate of the northern branch of the Runan-Nanxi fault segment since the Holocene is about 2.37±0.15 mm/a.

关 键 词：丽江-小金河断裂 全新世 滑动速率 青藏高原东南缘 

分 类 号：P315.2[天文地球—地震学]