ISSN 1003-8035 CN 11-2852/P

    云南鲁甸Ms6.5级地震震后滑坡的时空分异特征

    Spatio-temporal differentiation of landslide after the Ms6.5 Ludian earthquake in Yunnan Province

    • 摘要: 2014年8月3日云南鲁甸发生的Ms6.5级地震触发了大量滑坡,受强烈地震触发的滑坡震后恢复速度慢、恢复难度大且具有扩大复发的可能,会对道路、水体、生态环境造成长期影响,因此,探究其长时间时空分异具有必要性。以受地震影响的314 km2为研究区域,首先基于ENVI深度学习方法提取震后滑坡并编制其多时相数据清单,在此基础上,从滑坡时空分布特征、滑坡时空面积变化特征以及滑坡活动演化进行时空分异分析。结果表明:(1)地震后,滑坡数量和面积急剧增加,在随后的8年时间内,总体呈现逐渐减少趋势,地震触发滑坡以面积小于0.01 km2的小型滑坡为主,集中分布于河谷两侧,同时距震中2000 m、地震烈度Ⅸ级范围内分布较为明显;(2)随时间推移,震后滑坡活动率总体表现为逐渐减弱趋势,截至2022年7月,地震触发滑坡只有6.08%的滑坡仍处于活动状态,表明地震对滑坡的影响已经逐渐减弱;(3)地震后滑坡的活动演化可以分为3个阶段:滑坡强活动期(2014年8月—2016年7月)、中等活动期(2016年8月—2021年8月)、弱活动期(2021年9月—2022年7月)。

       

      Abstract: A large number of landslides were triggered by the Ms 6.5 magnitude earthquake that occurred in Ludian, Yunnan Province, on August 3, 2014. Landslides triggered by strong earthquakes exhibit slow post-earthquake recovery, high recovery difficulty, and tend to recur and expand, which can have long-term impacts on roads, water bodies, and ecological environments. Therefore, it is necessary to explore their long-time spatial and temporal variability. Taking the 314km2 area affected by the earthquake as the study area, post-earthquake landslides were first extracted and a multi-temporal data list was compiled using the ENVI deep learning method. Based on this, the spatial-temporal differentiation analysis was carried out focusing on the spatio-temporal distribution characteristics of landslides, changes in spatio-temporal area, and the evolution of landslide activities. The results show that: (1) following the earthquake, the number and area of landslides increased dramatically, gradually decreasing over the subsequent 8 years. Earthquake-triggered landslides were primarily small-scale, with an area of less than 0.01 km2, concentrated on both sides of the river valley, and distributed more prominently within 2,000 meters from the epicenter and within seismic intensity IX; (2) over time, the post-earthquake landslide activity rate generally showed a gradual weakening trend, with only 6.08% of the earthquake-triggered landslides still active as of July 2022, indicating a gradual weakening of the earthquake's impact on landslides; (3) the activity evolution of post-earthquake landslides can be divided into three phases: the period of strong landslide activity (August 2014-July 2016), the period of moderate activity (August 2016-August 2021), and the period of weak activity (September 2021-July 2022).

       

    /

    返回文章
    返回