School of Emergency Science, Xihua University, No.9999 Hongguang Rd, Chengdu, 610039, Sichuan, China.
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 61005, China.
Sci Rep. 2021 Dec 8;11(1):23666. doi: 10.1038/s41598-021-03125-x.
On August 20, 2019, at 2 a.m., a disastrous debris flow occurred in Chediguan gully in Yinxing town, China. The debris flow destroyed the drainage groove and the bridge at the exit of the gully. In addition, the debris flow temporarily blocked the Minjiang River during the flood peak, flooding the Taipingyi hydropower station 200 m upstream and leaving two plant workers missing. To further understand the activity of the debris flow after the Wenchuan earthquake, the characteristics of this debris flow event were studied. Eleven years after the Wenchuan earthquake, a disastrous debris flow still occurred in the Chediguan catchment, causing more severe losses than those of earlier debris flows. In this paper, the formation mechanism and dynamic characteristics of this debris flow event are analysed based on a drone survey, high-definition remote sensing interpretations and other means. The catastrophic debris flow event indicates that debris flows in the Wenchuan earthquake area are still active. A large amount of dredging work in the main gully could effectively reduce the debris flow risk in the gully. In addition, it is also important to repair or rebuild damaged mitigation measures and to establish a real-time monitoring and early warning system for the high-risk gully.
2019 年 8 月 20 日凌晨 2 点，中国映秀镇车地关村发生了一场灾难性的泥石流。泥石流摧毁了沟口的排水渠和桥梁。此外，泥石流在洪峰期间暂时阻断了岷江，导致上游 200 米处的太平驿水电站被淹没，两名工厂工人失踪。为了进一步了解汶川地震后泥石流的活动情况，研究了这次泥石流事件的特征。十一年后，车地关流域仍发生了一场灾难性的泥石流，造成的损失比早期泥石流更为严重。本文基于无人机调查、高清晰度遥感解译等手段，分析了此次泥石流事件的形成机制和动力特征。这次灾难性的泥石流事件表明，汶川地震地区的泥石流仍然活跃。对主沟进行大量的疏浚工作可以有效地降低沟内泥石流的风险。此外，修复或重建受损的减灾措施，以及建立高风险沟壑的实时监测和预警系统也很重要。
