Abstract
A large quantity of artesion groundwater spouted here and there in the alluvial fan of Fujisawa River near the epicenters of Matsushiro earthquake swarm in Nagano Prefecture, Japan, while this swarm was in full activity. And a few landslides were caused by this groundwater in this fan.
The groundwater pressure at different depths in some boreholes were observed. The quality and some other characters of the groundwater, along with some features of the landslides, were examined.
Fluctuations of the pressure, its estimated values at occurences of the landslides and characters of the groundwater quality are discussed.
