| 摘要: |
| 根据卫星影像解译和野外调查结果，本文重点分析研究楚雄-南华断裂的活动特征、最新活动时代、第四纪盆地的成因以及与1680年楚雄 6?级地震的关系。吕合、南华等多处第四纪断层剖面揭示了断错龙川江Ⅱ、Ⅲ级阶地晚更新世晚期堆积，表明该断裂是一条晚第四纪活动断裂，其最新时代为晚更新世晚期乃至全新世，运动性质以右旋走滑运动为主，水平走滑速率1.6～2.0mm/a。沿断裂发育有楚雄、南华、子午等多个第四纪拉分盆地。历史上，断裂附近曾发生1680年楚雄 6?级地震和多次中强地震，楚雄-南华断裂为这些地震的发震构造。从更大区域范围看，它与东部的曲江断裂、石屏-建水断裂一起，构成一组斜列的右旋走滑为主的活动断裂带。这种运动学特征类似于川滇菱形块体西南边界的红河断裂带，与川滇菱形块体SE向逃逸(运动)有关。 |
| 关键词: 楚雄南华断裂 晚第四纪 右旋走滑 地震 |
| DOI： |
| 分类号: |
| 基金项目:2014年度地震科技星火计划项目(XH14047)、国家自然科学基金项目(41472204)资助 |
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| Late Quaternary activity of the ChuxiongNanhua fault and the 1680 Chuxiong M 6¾ earthquake |
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Chang Zufeng1) Chang Hao1) Li Jianlin1) Hou Jiaxue2) Song Zhifeng2) Mao Depei2)
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1)Earthquake Administration of Yunnan Province，Kunming 650041，China；2)Earthquake Administration of Chuxiong Yi Aulonomous Prefecture，Yunnan Province, Chuxiong 675000，China
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| Abstract: |
| According to the results of the satellite imagery interpretation and field investigation，we study the active features and the latest active times of the Chuxiong-Nanhua fault，the Quaternary basins formation mechanism，and the relations of the fault and the 1680 Chuxiong M6? earthquake. Several Quaternary profiles at Lvhe，Nanhua reveal that the fault has offset the late Pleistocene deposits of the T2 and T3 terraces of the Longchuan River，indicating that the fault was obviously active in late Quaternary. The Chuxiong-Nanhua fault has been dominated by dextral strike slip motion in late Quaternary，with an average rate of 1.6～2.0mm/a. Several pull apart Quaternary basins of Chuxiong，Nanhua，and Ziwu etc. have been developed along the fault. The 1680 Chuxiong M6? earthquake and several moderate earthquakes occurred nearby the fault historically. The Chuxiong-Nanhua fault are the seismogenic structure of those earthquakes，the latest fault movement is in late-Pleistocene，even Holocene. In a larger area，the Chuxiong-Nanhua fault and the eastern Qujiang fault and the Shiping fault composed a set of NW treading oblique orientation active faults，and the motion characters are mainly of dextral strike slip. The motion characters，like the Red River fault of the Sichuan-Yunnan Rhombic Block southwestern boundary，is concerned with the escaping movement of the Sichuan-Yunnan Rhombic Block. |
| Key words: The ChuxiongNanhua fault LateQuaternary Dextral strike slip Earthquake |
