Abstract
Abstract. This publication highlights theoretical work that could explain five different empirical observations indicating a direct relationship between magnetic fields and earthquakes, which would allow the description of a causal mechanism prior to and during the occurrence of earthquakes. These theoretical calculations seek to elucidate the role of the magnetic field in different aspects of solid Earth dynamics, with an interest in the study and comprehension of the physics that could generate earthquakes accompanied by simultaneous magnetic signals within the lithosphere. The motion of charged edge dislocations (MCD) model and its correlation with the magnetic field have been used in order to include the generation of electric currents. The electric currents resulting from stress variation in the lithosphere help us to analyze the lithosphere as a critical system, before and after the occurrence of earthquakes, by using the concept of earthquake entropy. Where it is found that the nonexistence of seismic and magnetic precursors could be interpreted as a violation of the second law of thermodynamics. In addition, the seismic moment and the moment magnitude of some great earthquakes are quite accurately calculated using the coseismic magnetic field. The distance-dependent coseismic magnetic field has been theorized for some of the largest recorded earthquakes. The frequency of oscillation of the Earth's magnetic field that could be associated with earthquakes is calculated and is consistent with the ultra-low-frequency (ULF) signals that some authors propose in the so-called “LAIC effect” (lithosphere–atmosphere–ionosphere coupling). Finally, the location and dimensions of the microcracks that explain some anomalous magnetic measurements are shown.
Highlights
There is still no unified causal mechanism that is widely accepted and that may account for the physics of all these observations prior to or during the occurrence of an earthquake (Hough, 2010), the laboratory evidence shows the possibility of an increase in the conductivity of rocks when subjected to stress changes, through either microcracks or chemical imperfections (Freund, 2003; Anastasiadis et al, 2004; Cartwright-Taylor et al, 2014)
This work studied the role of the magnetic field in the lithospheric dynamics, the physics that could be associated with various measurements that relate magnetic fields and earthquakes in a complete cycle, i.e., from a stress diswww.nat-hazards-earth-syst-sci.net/19/1639/2019/
This was possible by assuming that the behavior of laboratory samples would exhibit the same physics as lithospheric rocks
Summary
A number of investigations attempting to relate the magnetic field to seismic events have emerged over the past few years, (e.g., Park, 1996; Surkov et al, 2003; Johnston et al, 2006; Balasis and Mandea, 2007; Sgrigna et al, 2007; Saradjian and Akhoondzadeh, 2011; Varotsos et al, 2011; De Santis, 2014, 2017; Donner et al, 2015; Schekotov and Hayakawa, 2015; Daneshvar and Freund, 2017; Cordaro et al, 2018, 2019; Marchetti and Akhoondzadeh, 2018; Pulinets et al, 2018; among others). The generation of current and magnetic field resulting from stress changes in rocks and their relationship with earthquakes has been shown empirically and theoretically by Vallianatos and Tzanis (2003), Anastasiadis et al (2004), and Scoville et al (2015), among others. We show that coseismic magnetic variations can reach hundreds of kilometers of radial distance from the rupture area. Ionospheric disturbances would not be expected for earthquakes with moment magnitudes less than ∼ Mw 7
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
