贵阳鱼梁河河谷地貌形态特征研究

Geomorphologic characteristics of Yuliang River Valley in Guiyang

鱼梁河是一条发源于龙里县,流经龙洞堡高原面,由乌当盆地汇入南明河的河流,河长40.8公里、流域面积390.4平方公里,是南明河的一级支流。鱼梁河上游流经龙洞堡高原面,属于构造稳定环境;下游流经乌当盆地,属于相对沉降环境;其中穿过了乌当逆冲推覆断层构造带。河谷形态会对不同构造环境做出积极响应。所以,定量的测量河谷地貌形态特征对于揭示河谷地貌与地质构造活动的关系是非常有价值的。该文利用ArcGIS软件根据DEM数据提取了鱼梁河流域范围和河流纵剖面,后又选取了19个测量点,实地测量河谷宽度、深度并绘制横剖面图。结果发现,位于上游构造环境稳定的高原面的河谷是窄而浅的;位于中游隆起山地的河谷是窄而深的峡谷;位于下游沉降环境的乌当盆地的河谷是宽而浅的。河谷形态可以很好的反映构造环境。

The Yuliang River is a tributary of the Nanming River,which originates from Longli County,and flows through the Longdongbao Plateau and the Wudang Basin before flowing into the Nanming River.The river is 40.8 kilometers long and has a drainage area of 390.4 square kilometers.The upper reaches of the Yuliang River flows through the Longdongbao Plateau,which belongs to the tectonic stable environment.The lower reaches of the Yuliang River flows through the Wudang Basin,which belongs to the relative subsidence environment.The river also passes through the Wudang Thrust Nappe Structure Belt.The river valley form will make positive response to different tectonic environments.Therefore,it is of great value to quantitatively measure the morphological characteristics of the river valley for revealing the relationship between the geomorphology and the geological tectonic activities.Using ArcGIS software,this paper extracts the drainage area and the longitudinal section of the Yuliang River based on DEM data,and then selects 19 points to measure the width and depth of the river valley and draw the cross section map.The results show that the upper reaches of the river valley that locate in the plateau face are narrow and shallow;the middle reaches of the river valley that locate in the uplifted mountains are narrow and deep;and the lower reaches of the river valley that locate in the subsidence environment of the Wudang Basin are wide and shallow.The river valley shape can well reflect the tectonic environment.