Method and system for predicting rapid motion in earth's crust on basis of electromagnetic field observation

摘要

A casing pipe is inserted into a drilled hole reaching the inside of a confined aquifer in which groundwater is stored and flows or a position near the confined aquifer. A measuring device measures an electromagnetic field at the distal end of the casing pipe. An analyzing device analyzes data concerning the electromagnetic field measured by the measuring device to sense motion of ground pore water, thereby predicting rapid motion in the earth's crust, such as a volcanic eruption, an earthquake, a landslide and ground collapse. The casing pipe is an electrically conductive pipe having a non-magnetic screen portion formed at the distal end thereof so that recycling groundwater passes through the screen portion. The measuring device includes an electromagnetic field sensor placed in the screen portion and the conductive casing pipe as an electrode for measuring an electric potential relative to an electric potential at the earth's surface detected with a reference electrode.