抄録
Some geophysical explorations were conducted to investigate the underground structure around the Fukui Earthquake Fault, FEF, reported by TSUYA (1950). A seismic reflection survey was carried out at a dry river bed along the Kuzuryu River across the FEF. The gravity survey was also performed around the seismic reflection survey line. The seismic reflection profile shows that the Quaternary sedimentary cover is 200 to 300m in thickness and tilts gently westward. The profile also shows an existence of somewhat peculiar block with width of several hundred meters at the FEF. This block corresponds to the lower gravity anomaly zone obtained from the local gravity analysis. We concluded that the FEF with many ground failures induced by the earthquake has not been effectively displaced in vertical movement and the successive fault movement related in the FEF has thickened fault gouge layer along the FEF.