Active EM sounding for early warning of earthquakes and volcanic eruptions

Abstract

Strong earthquakes (EQs) and dramatic volcanic eruptions (VEs) have a great impact on social and industrial communities. In spite of long-term studies, the problem of reliable predictions of EQs or VEs has not yet been solved. Proposed here is an active method for electromagnetic (EM) sounding of the Earth crust in ULF band. It is based on the use of a source of EM field such as a long linear cable, and a magnetometric monitoring part that can be placed in a seismoactive zone or volcanic area. After initial compensation of the primary field, the small detected deviations of conductivity and structure in crustal region caused by stresses before EQs or magma movements before VEs change the picture of the magnetic field observed at the surface. The main parameters of the active EM sounding are estimated and it is shown that the method has good perspective for EQs and VEs prediction.