摘要
温泉县孟克沟流域由1条主沟及4条主要支沟构成,具有发育数量较多、规模较小、泥石流发生频率较多的特征。流域平面形态呈漏斗状,地势总体南西高北东低,沟槽横断面呈"V-U"字型。降水主要集中于每年的5—9月,强降水在短时间内汇聚成地表径流,并与沟谷中松散碎屑物质共同运动形成水石流。泥石流主沟侵蚀速率略大于支沟,平均侵蚀切割深度大于0.5m,最大泥痕深度位于中游,侵蚀切割深度最大。堆积区位于泥石流沟下游,堆积厚度大,一次性堆积量大,其发育现状基本没受外界因素的影响,活动趋势具有继承性。建议泥石流防治工程排洪系统应与天然冲沟衔接,且应尽量减少对草场的影响和占用;针对泥石流灾害上游侵蚀下切,下游堆积淤埋的破坏机制,充分利用下游现存的采砂坑。根据泥石流活动的时空特点,在下游采取停淤、减势、排导等的防治工程措施,可减轻或化解泥石流灾害的威胁。
Mengkegou valley in Wenchuan county,including five major branch gullies and one main gully,is characterized by small size,large quantity of growing branches and high frequency of debris flow.The plane shape of the basin is funnel-shaped.The overall topography is high in the south west and low in the north east,and the cross section of the trench is in the‘V-U’shape.The precipitation is mainly concentrated from May to September every year,and the heavy precipitation converges into runoff on the surface in short time,which moving together with the unconsolidated clastic material along the valley forming water-rock debris flow.The accumulation area is located in the lower reaches of the debris flow gully,with characteristics of thick accumulation and large amount of one-time accumulation,its development status is basically not affected by external factors,and the activity trend is inherited.It is suggested that the flood drainage system of the debris flow prevention and treatment project should be connected with the natural gully,and measures should be taken to minimize the influence and occupation of grasslands.The existing mining pits in the lower reaches should be fully utilized according to the destruction mechanism of erosion in the upper reaches and accumulation in the lower reaches of debris flow disasters.Based on the space characteristics of debris flow movement,the prevention and treatment measures such as siltation,reduction and drainage in the lower reaches can relieve or resolve the threats of debris flow disasters.
作者
李俊
李杰
Li Jun;Li Jie(Chongqing 208 Engineering Survey and Design Institute Co.,Ltd.,Chongqing 400700,China;The First Hydrology&Engineering Geology Group of Xinjiang Geology and Mineral Resource Bureau,Urumqi 830091,China)
出处
《吉林水利》
2021年第6期11-15,共5页
Jilin Water Resources
关键词
泥石流
孟克沟
特征
形成条件
防治
debris flow
Mengkegou gully
characteristics
formation conditions
prevention and control
