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arXiv · 1906.01116

THMC instabilities and the Multiphysics of Earthquakes

K. Regenauer-Lieb·M. Hu·C. Schrank
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Abstract

Theoretical approaches to earthquake instabilities propose shear dominated instabilities as a source mechanism. Here we take a fresh look at the role of possible volumetric instabilities preceding a shear instability. We investigate the phenomena that may prepare earthquake instabilities using coupling of Thermo-Hydro-Mechano-Chemical (THMC) reaction-diffusion equations in a THMC diffusion matrix. We show that the off-diagonal cross-diffusivities can give rise to cross-diffusion slow (no inertia) pressure waves and propose that a resonance phenomenon of the long-wavelength limit causes constructive interference and triggers the seismic moment release.

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K. Regenauer-Lieb, M. Hu, C. Schrank. 2019-06-03. THMC instabilities and the Multiphysics of Earthquakes. https://arxiv.org/abs/1906.01116

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