1989 年 42 巻 1 号 p. 33-38
A magnetotelluric survey was carried out at the Hanaori fault area in northeastern Kinki district. Apparent resistivities at four frequencies of ELF band (7.8, 14.0 and 20.4Hz) and VLF band (17.4kHz) were measured along two survey lines perpendicular to the strike of the fault. Two-dimensional analysis using the finite-element method gives an underground resistivity model across the Hanaori fault. The model indicates that a low resistivity zone is 1.4km wide and extends to a depth of more than 800m. We interpret this zone as resulting from fault activities.