汤沛 1祝传兵 1姜跃斌 2周翠琼 1李晓梅 2张令泽 1肖华宗 1张文鋆1
作者信息
- 1. 自然资源部高原山地地质灾害预报预警与生态保护修复重点实验室,云南 昆明 650216||云南省高原山地地质灾害预报预警与生态保护修复重点实验室(筹),云南 昆明 650216||云南省地质环境监测院,云南 昆明 650216
- 2. 云南地质工程第二勘察设计研究院有限公司,云南昆明
- 折叠
摘要
Abstract
Eryuan county is located in the northern part of Dali Bai Autonomous Prefecture,Yunnan Province.It borders Heqing county and Binchuan county to the east,Dali City and Yangbi county to the south,Yunlong county to the west,and Jianchuan county to the north.The maximum straight-line distance from east to west is about 80 km,and the maximum straight-line distance from north to south is about 68 km.The circumference of the county is about 340 km.Eryuan county is located at the collision zone between the Indian Plate and the Eurasian Plate,and is strongly influenced by the Himalayan orogeny.Since the Miocene,the plateau has experienced substantial uplift,accompanied by vigorous neotectonic movements.Earthquakes are common in this area due to its complex and varied geological and topographical conditions.The terrain is characterized by significant cutting,with high mountains and deep valleys.Additionally,this area has well-developed water systems,and geological disasters occur frequently in this area.It is a high-risk area for geological disasters in Yunnan Province.Since 2012,casualties resulting from geological disasters in Eryuan have primarily been attributed to rainstorm-induced gully-type debris flows.This type of debris flow disaster in the Tiejia river basin is characterized by sudden heavy rainfall occurring in the early morning,leading to large-scale events at a high level of risk.This area also serves as a site for projects of monitoring and early warning geological disasters.It represents a typical case for studies on gully-type debris flow disasters throughout the entire county.
Based on the characteristics of gully-type debris flows in the Tiejia river basin,and in accordance with the Technical Specification for Geological Disasters Monitoring and Early Warning by Combination of Professional and Masses Methods and the Technical Guidelines for Monitoring and Early Warning of Geological Hazards in Yunnan Province(Trial),in this study,we employed rainfall stations and mud water levels as main monitoring sites and data,video monitoring stations as auxiliary monitoring sites,and warning broadcasting stations as sites for on-site warning techniques.We analyzed the background and movement characteristics of debris flow disasters in the Eryuan gully.Additionally,we selected a warning model based on the similarities in geological environment and the differences in disaster conditions between the gullies of the Lanlin river and of the Heilong river.Because the main gully of the Lanlin river is shorter than that of the Heilong river,has a smaller drainage area,and features a flatter gully,we adopted a single-parameter warning model to ensure response time.Besides,the development of the main gully of the Heilong river is more tortuous and complex,and it covers a larger watershed area;therefore,we adopted a multi-parameter warning model to reduce the false alarming rate.Based on the analysis of the early warning results of the two gullies of debris flows,and the selection and layout of monitoring and early warning equipment for rainstorm-induced debris flows,we illuminated the setting of model thresholds,and summarized the experience and enlightenment of monitoring and early warning debris flows in Eryuan.
The gully debris flows triggered by sudden heavy rainfall are often large in scale,possess strong destructive power,have a brief duration of occurrence,and threaten numerous objects.This presents a key challenge in the prevention of geological disasters in Eryuan county.In the work of monitoring and early warning,we should focus on the monitoring of the strong rainfall that triggers debris flows upstream and the flood flows that causes disasters in the middle and downstream areas of the debris flows.In the work of early warning response,we should identify the main threat after the disaster,and ensure that the deployed warning equipment and warning information are transmitted in a timely manner.We should comprehensively set warning thresholds and models,based on the characteristics of disasters.We should also prioritize the resettlement of evacuees and its regulation.Even if we have implemented projects of controlling debris flows,it is likely to occur debris flows under the influence of extremely heavy rainfall,especially the rainstorm-induced gully-type debris flows taking place in the Tiejia river.Projects of monitoring and early warning can still serve as an effective supplementary measure for engineering management after disaster treatment,so as to enhance the capabilities of comprehensive prevention and control of debris flows.关键词
地质灾害/监测方法/监测预警/云南洱源/泥石流Key words
geological hazards/monitoring methods/monitoring and warning/Eryuan/Yunnan/debris flow分类
天文与地球科学
