北京菜食河流域四海——珍珠泉段泥石流特征与危险性评价  

Characteristics and risk assessment of debris flow in Sihai-Zhenzhuquan section of Caishi River Basin,Beijing

作　　者：李宏宇 邹润 任航 LI Hongyu;ZOU Run;REN Hang(Research Institute No.240,CNNC,Shenyang 110000,Liaoning,China)

机构地区：[1]核工业二四〇研究所,辽宁沈阳110000

出　　处：《矿产勘查》2025年第2期422-432,共11页Mineral Exploration

基　　金：北京市延庆区泥石流沟精细调查与评价项目(0747-1761SITCN426-4)资助。

摘　　要：北京菜食河流域延庆段曾发生多处泥石流事件,严重影响了当地人民的生产、生活。本文选取菜食河流域四海—珍珠泉段受灾严重、潜在经济损失最大的17条沟谷为研究对象,在野外精细调查的基础上,应用GIS的大数据统计功能,统计研究各泥石流分区特征和泥石流形成条件、泥石流易发性和活动特征;选择了松散物质储量、沟岸平均坡度、汇水面积、相对高差、主沟长度、年平均降雨量和植被覆盖率共7种评价因子,划分了泥石流危险性等级。结果表明:菜食河流域四海—珍珠泉段泥石流沟物源条件包括沟道冲洪积、坡残积、人类活动堆积和崩滑塌堆积体4类,物源总储量达1681.30×10^(4) m^(3),平均厚度1.01 m;暴雨洪峰流量整体较大,其中最小为1.53 m^(3)/s,最大为31.63 m^(3)/s;危险性评价结果显示流域两侧沟谷为低危险的沟5条,中危险的沟7条,高危险的沟5条,其中,高危险泥石流沟严重威胁流域沿岸珍珠泉乡、四海镇沿河分布的村庄、道路,评价结果对延庆区开展小流域泥石流工程治理、防灾减灾具有重要科学意义。Frequent debris flow events in the Yanqing section of Beijing’s Caishi River Basin pose significant threats to local communities and infrastructure.This study focuses on 17 gully systems within the Sihai-Zhenzhuquan segment,combining field investigations with GIS-based statistical analysis to evaluate debris flow characteristics,formation conditions,susceptibility,and activity patterns.A risk assessment framework was estab-lished using seven key parameters:loose material reserves(1681.30×10^(4) m^(3)),average slope gradient of gully banks(1.01 m),catchment area,relative elevation difference,main channel length,annual rainfall,and vegetation cover-age.Results indicate that debris flow source materials in the study area primarily consist of channel alluvium,slope deposits,anthropogenic accumulations,and landslide deposits.Under rainfall scenarios with return periods of 50 years(P=2%)and 5 years(P=20%),peak discharge rates reach 31.63 m^(3)/s and 1.53 m^(3)/s,respectively.Risk classifi-cation reveals five low-risk,seven medium-risk,and five high-risk gullies.High-risk gullies critically endanger villages and transportation networks in Zhenzhuquan Township and Sihai Town.These findings provide a scientific foundation for targeted engineering mitigation and disaster reduction strategies in the Yanqing District.

关 键 词：菜食河流域 四海—珍珠泉段 分区特征和形成条件 泥石流活动特征 危险性评价 

分 类 号：P642[天文地球—工程地质学]