Large-scale electromagnetic perturbations triggered during landslide events
摘要
The occurrence of landslides is considered to be preceded by the instinct of rock breaking and strata failure, which could lead to the emission of electromagnetic radiation.
Methodology and resultsWe eliminated the influences from solar activities, lightening, artificial noises, and seismogeneric fault to examine the relationship between magnetic perturbations and landslides. The correlation coefficient method is further employed to investigate the in-phase and out-of-phase relationship between geomagnetic data collected from approximately 100 stations. The analytical results indicate that strong positive (> 0.8) and strong negative (< − 0.8) correlation coefficients associated with landslides are distributed within areas with an incredibly large radius, approximately 500 km. Two interfaces between strong positive and negative correlation coefficients were found extending from the landslide sites, aligning with the direction of the landslide flow and its orthogonal direction.
Simulation and conclusionThe significant discrepancy in correlation coefficients across adjacent areas implies the existence of electric currents. Using the Biot-Savart Law, we calculated the landslide-associated magnetic perturbations, and a rough match between numerical and observational results demonstrates that electromagnetic perturbations arise several minutes before landslide occurrence.