尤溪县蠕动滑坡地质灾害环境因素探讨

Discussion on the Environmental Factors of Geologic Hazards Caused by a Creep Landslip in Youxi County

蠕动滑坡是尤溪县地质灾害主要类型之一,其分布的地形(地貌)环境为凹型坡,诱发动力来自降雨的季节性地表水和地下水的推动力,发生蠕动滑坡地段的基岩主要为晚侏罗世小漈序列中细粒石英闪长岩和细粒石英闪长岩,早侏罗世梨山组上段泥岩、粉砂质泥岩和晚侏罗世南园组的中酸性火山岩,地层倾向与坡向相同且倾角小于坡角,土体主要为含砂量少的塑性粘土。蠕动滑坡具有滑动速度缓慢,持续时间长,影响范围较大、治理困难等特点。

The creep landslip is one of main geologic hazards in Youxi County and is distributed over the concave-form slopes. The moving forces inducing the creep landslip hail from the seasonal surface water by the rainfall and the driving force of underground water. The bed rocks in which the creep landslip occurs are the late Jurassic medium-fine-grained quartzdiorite and fine-grained quartzdiorite and the early Jurassic mudstone and silty mudstone and the late Jurassic Intermediate-acid volcanic rocks. The dip direction of the strata is coincide with the exposure of slope and the dip angle is less than the slope angle. The earth body is mainly the plastic clay with little sand content. The creep landslip is characteristic of a slow sliding velocity, a longer duration time, a larger influence circle and harder abatement.