Abstract
In this paper, the mechanism of pore water fluctuation is discussed through the data obtained from the field observation in the Kuchisakamoto landslide area. From the discussion of hydrogeological structure and the result of seepage flow analysis, the fluctuation of pore water pressure in the lower block of landslide area is caused by the increase of artesan pressure, which can be easily propagated through the aquifer layer and water path exsisting in the sliding mass, originated from the infiltration of rain through the tension cracks.
