Fractal Clustering as Spatial Variability of Magnetic Anomalies Measurements for Impending Earthquakes and the Thermodynamic Fractal Dimension

Abstract

Several studies focusing on the anomalies of one specific parameter (such as magnetic, ionospheric, radon release, temperature, geodetic, etc.) before impending earthquakes are constantly challenged because their results can be regarded as noise, false positives or are not related to earthquakes at all. This rise concerns the viability of studying isolated physical phenomena before earthquakes. Nevertheless, it has recently been shown that all of the complexity of these pre-earthquake anomalies rises because they could share the same origin. Particularly, the evolution and concentration of uniaxial stresses within rock samples have shown the generation of fractal crack clustering before the macroscopic failure. As there are studies which considered that the magnetic anomalies are created by lithospheric cracks in the seismo-electromagnetic theory, it is expected that the crack clustering is a spatial feature of magnetic and non-magnetic anomalies measurements in ground, atmospheric and ionospheric environments. This could imply that the rise of multiparametric anomalies at specific locations and times, increases the reliability of impending earthquake detections. That is why this work develops a general theory of fractal-localization of different anomalies within the lithosphere in the framework of the seismo-electromagnetic theory. In addition, a general description of the fractal dimension in terms of scaling entropy change is obtained. This model could be regarded as the basis of future early warning systems for catastrophic earthquakes.

Subduction as a Smoothing Machine: How Multiscale Dissipation Relates Precursor Signals to Fault Geometry

“…Recent work on multiscale thermodynamics provides this framework, offering insights into entropy production and the thermodynamic fractal dimension as measures of energy dissipation and complexity. One of the key equations in multiscale thermodynamics work relates the thermodynamic fractal dimension (D) to the multiscale entropy production balance [35]:…”

“…It captures the relative contribution of entropy production at different scales and provides a measure of the overall energy dissipation in the system. According to Venegas-Aravena et al, 2022 [35], the parameter Ω V can be expressed as:…”

“…Although there are studies linking measurements to earthquake magnitude [9,20,[26][27][28][29][30], the crucial question of actual causation, which represents the fundamental link between the measured signals and the underlying physics of earthquake rupture, is addressed by only a limited number of researchers within the pre-earthquake signal community [31][32][33][34][35][36]. This gap in our understanding has generated concerns and skepticism within the seismological community, as the reliability and predictive capabilities of pre-earthquake measurements are called into question [37,38].…”

“…Significant progress has been achieved in the integration of pre-earthquake signals of the lithosphere with seismic rupture parameters, employing the principles of multiscale thermodynamics and entropy production of rocks [34,35]. A crucial parameter in this framework is the thermodynamic fractal dimension, which accounts for the dissipation of energy across different scales, and specifically characterizes the distribution of multiscale cracking within materials.…”

“…In that line, one notable consequence of large-scale entropy production is the emergence of smoother fault surfaces [35,36]. This is relevant because seismological studies describe the fault interface and the seismic source as heterogenous [55][56][57], implying that friction coefficients depend on the roughness of the surface.…”