Distribution Relationship Between Veins of Groundwater, Slope angles, and Slope Failures at a Landslide in Crystalline Schist Area

Abstract

結晶片岩の地すべり地において，地温探査，安定解析および水質分析結果から斜面崩壊と地下水脈の分布の関係について検討した。その結果，崩壊発生箇所は地下水脈の分布に関連すること，この水脈は浅部のみを流れる地下水，山体内での貯留時間が短い深部地下水，この時間が長い深部地下水であることが判明した。また，安定解析結果と水脈分布情報を併用したところ，崩壊危険斜面をある程度絞り込めることが示唆された。

The present study is concerned with the assessment of the distribution of thepotential considered about the location of slope failures in a crystalline schist areatriggered by heavy rainfall based on the results of one-meter depth undergroundtemperature survey, slope stability, and water quality analysis. The slope failures appearto concentrate around the vein of groundwater and the veins of groundwater rising fromdeep layers. There are two types of groundwater from origination the deep layers, one isshort storage time the other is long storage time. By combining the results of stabilityanalysis and distribution of veins of groundwater, it is suggested that the localization ofzones of high potential for slope failure can be narrowed down to some extent.