四川广安区观塘镇地质灾害特征及其成因

The Geohazard Characteristics and the Genetic Mechanism of Guantang Town of Guang'an District,Sichuan Province

四川广安区观塘镇地质灾害发育以崩塌、滑坡和潜在不稳定斜坡为主。区内地质灾害空间分布上具有明显的不均一性,受地形影响明显。该区地貌以中丘为主,广泛分布软硬相间的近水平中生代红层,一般丘顶为巨厚层砂岩,砂岩内大间距的垂直裂隙发育。渠江及其支流切割强烈,在渠江及支流两岸形成上硬下软、上陡下缓的特殊边坡结构,降雨不均与人类工程活动扰动等多因素作用是导致本区地质灾害发育的主要原因。

The geohazards are well developed in Guantang town of Guang＇an district,Sichuan province.The main geohazards are avalanches,landslide and latent instability slopes.In the area the space distribution of the geohazards is obviously inhomogeneous,which affected by land form.Land form in this area is mainly composed of medium hill.The Mesozoic redbeds are widely distributed in the region,and the lithological features are hard sandstone interbedded with soft mudstone,whose attitude is approximate horizontal.Commonly there are huge thick sandstone layers on summit,vertical and large-spacing interval cracks are developed in the sandstone layer.Qujiang river and its tributary strongly cut the land form in this area,and forming special slopes,i.e hard sandstone with steep slope on the top and soft mudstone with gentle slope underlying,non-uniform rainfall and human activities are two main reasons leading to the development of geohazards.