Magnetic fields induced by a mechanical singularity in a magnetoelastic half plane and their applications to the seismicities in the crust of the Chinese continent

TL;DR

This study models how magnetic fields generated by mechanical singularities in a magnetoelastic half-plane relate to seismic activity, suggesting magnetic observations can help locate and assess earthquake risk zones in China's crust.

Contribution

The paper provides exact solutions for magnetic fields induced by line singularities in a magnetoelastic half-plane and applies these results to earthquake epicenter localization in China.

Findings

Over 80% of earthquake epicenters are near zero-contours of vertical magnetic induction.

Zero-contours of magnetic induction correlate with active tectonic and seismogenic zones.

Magnetic field analysis offers a potential tool for earthquake risk assessment and early warning.

Abstract

The interaction between the magnetic field and the elastic deformation field in the crust is studied in a simplified way. The magnetic fields generated by the line singularities in a magnetized elastic half-plane are investigated. Using the general solution and Fourier transform technique, the exact solutions for the generated magnetic inductions due to various cases are obtained in a closed form. The results show that the line concentrated force will induced a perturbed magnetic field; The induced magnetic field will indicate the line concentrated force in reverse. The distribution of the vertical component of the magnetic induction caused by the line mechanical singularities is simpler than that of the horizontal component, and it is zero at the origin when the applied magnetic field and the line concentrated force satisfies some conditions. This result is applied to locate the epicenters of the earthquakes and historical earthquakes occurred in the Chinese continental crust. Results show that more than 80\% epicenters are at or near the zero-contours of the vertical component of the magnetic induction observed from satellite. These regions of zero-contours, especially those in active tectonic zones, could be the possible seismogenic zones in the future. The zero-contours of the vertical component of the magnetic induction from satellite could be as geophysical constraints to the risk information on the shallow seismicities, or they can be used as an early monitor for the shallow seismicities in the continental crust, or an auxiliary sign in the determination of the great historical earthquake.