title: Heterogeneous electrical structure of Kozu-shima volcanic island, Japan.
abstract: Nearly twenty anomalous geoelectric field changes were observed before earthquakes at Kozu-shima Island, Japan, from 1997 to 2000. In order to help locating the current sources of the observed anomalous changes, a bipole-dipole resistivity survey was conducted. From the resistivity survey, including current injection into the ground, it was found that various features of the anomalous changes were systematically different from those of changes caused by artificial sources and induction of geomagnetic disturbances. Moreover, it is suspected that the currents of anomalous changes were generated not near the ground surface but deep under the ground.
authors.affiliation: Earthquake Prediction Research Center, Tokai University, Shizuoka, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Orihara
authors.forename: Masashi
authors.initials: M
authors.lastname: Kamogawa
authors.forename: Toshiyasu
authors.initials: T
authors.lastname: Nagao
authors.forename: Seiya
authors.initials: S
authors.lastname: Uyeda
mesh_terms: D017097:Electric Impedance; D004560:Electricity; D004566:Electrodes; D005843:Geography; D007564:Japan; D018707:Volcanic Eruptions