Coupling mechanism between geoacoustic emission and electromagnetic anomalies prior to earthquakes
Micro-cracking in the earthquake preparation zone is accompanied by the generation of acoustic emission (AE). Even low-intensity AE can essentially modify the underground fluid dynamics owing to the influence of high-frequency acoustic field on filtration process. Laboratory experiments show that ac...
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Veröffentlicht in: | Research in geophysics 2014-11, Vol.3 (1) |
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Hauptverfasser: | , |
Format: | Artikel |
Sprache: | eng |
Online-Zugang: | Volltext |
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Zusammenfassung: | Micro-cracking in the earthquake preparation zone is accompanied by the generation of acoustic emission (AE). Even low-intensity AE can essentially modify the underground fluid dynamics owing to the influence of high-frequency acoustic field on filtration process. Laboratory experiments show that acoustic impact on pour sample destroys a film with bounded water and results in a steep increase of its permeability up to 2 orders of magnitude. Impulsive acoustic fields also decrease the effective viscosity of the fluid. The occurrence in the crust under pressure of a region with distinct hydrodynamic and electrokinetic parameters will result in an appearance of anomalous telluric and magnetic fields on the surface above. This effect is estimated analytically using a simple model with an ellipticshaped inhomogeneity. The suggested hypothesis about possible coupling between AE and geoelectrical anomalies needs observational verification. |
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ISSN: | 2038-9655 2038-9663 |
DOI: | 10.4081/rg.2014.5008 |