2018/01/04 by F. Giacco, Ferdinando Giacco, L. de Arcangelis +4 · 3 citations
Earth and Planetary Sciences · Engineering · Mathematics · Physics and Astronomy · #Acoustic wave #Acoustics #Composite material #Fluidization #Fluidized bed #Geology #Geometry #Geotechnical engineering #Granular flow and fluidized beds #Granular material #High-pressure geophysics and materials #Materials science #Mathematics #Mechanics #Overburden pressure #Perpendicular #Perturbation (astronomy) #Physics #Shear (geology) #Stress (linguistics) #cond-mat.soft #cond-mat.stat-mech #earthquake and tectonic studies #physics.geo-ph
paper · pdf · doi:10.1103/physreve.97.010901
published in Physical review. E 97(1), 010901 (American Physical Society)
openalex publication_date 2018/01/04 · arxiv created 2018/01/08 · arxiv updated 2018/02/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
According to the acoustic fluidization hypothesis, elastic waves at a characteristic frequency form inside seismic faults even in the absence of an external perturbation. These waves are able to generate a normal stress which contrasts the confining pressure and promotes failure. Here, we study the mechanisms responsible for this wave activation via numerical simulations of a granular fault model. We observe the particles belonging to the percolating backbone, which sustains the stress, to perform synchronized oscillations over ellipticlike trajectories in the fault plane. These oscillations occur at the characteristic frequency of acoustic fluidization. As the applied shear stress increases, these oscillations become perpendicular to the fault plane just before the system fails, opposing the confining pressure, consistently with the acoustic fluidization scenario. The same change of orientation can be induced by external perturbations at the acoustic fluidization frequency.