Seismic swarms unveil the mechanisms driving shallow slow slip dynamics in the Copiapó ridge, Northern Chile

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Münchmeyer, Jannes, Molina, Diego, Radiguet, Mathilde, Marsan, David, Baez, Juan-Carlos, Ortega-Culaciati, Francisco, Tassara, Andres, Moreno, Marcos, Socquet, Anne
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866909406518575104
author Münchmeyer, Jannes
Molina, Diego
Radiguet, Mathilde
Marsan, David
Baez, Juan-Carlos
Ortega-Culaciati, Francisco
Tassara, Andres
Moreno, Marcos
Socquet, Anne
author_facet Münchmeyer, Jannes
Molina, Diego
Radiguet, Mathilde
Marsan, David
Baez, Juan-Carlos
Ortega-Culaciati, Francisco
Tassara, Andres
Moreno, Marcos
Socquet, Anne
contents Like earthquakes, slow slip events release elastic energy stored on faults. Yet, the mechanisms behind slow slip instability and its relationship with seismicity are debated. Here, we use a seismo-geodetic deployment to document a shallow slow slip event (SSE) in 2023 on the Chile subduction. We observe dense, migrating seismic swarms accompanying the SSE, comprised of interface activity and upper plate splay faulting. Our observations suggest that the slow slip initiation is driven by structurally-confined fluid overpressure in the fluid-rich surroundings of a subducted seamount. This is consistent with an observed acceleration and expansion of the SSE after a $M_L=5.3$ earthquake likely triggering an increase in interface permeability. Historical earthquake swarms highlight the persistent structural control and recurrent nature of such slow slip events. Our observations provide insight into the interactions between slow slip and seismicity, suggesting they are controlled by creep on a fluid-infiltrated fault with fractally distributed asperities.
format Preprint
id arxiv_https___arxiv_org_abs_2411_18490
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Seismic swarms unveil the mechanisms driving shallow slow slip dynamics in the Copiapó ridge, Northern Chile
Münchmeyer, Jannes
Molina, Diego
Radiguet, Mathilde
Marsan, David
Baez, Juan-Carlos
Ortega-Culaciati, Francisco
Tassara, Andres
Moreno, Marcos
Socquet, Anne
Geophysics
Like earthquakes, slow slip events release elastic energy stored on faults. Yet, the mechanisms behind slow slip instability and its relationship with seismicity are debated. Here, we use a seismo-geodetic deployment to document a shallow slow slip event (SSE) in 2023 on the Chile subduction. We observe dense, migrating seismic swarms accompanying the SSE, comprised of interface activity and upper plate splay faulting. Our observations suggest that the slow slip initiation is driven by structurally-confined fluid overpressure in the fluid-rich surroundings of a subducted seamount. This is consistent with an observed acceleration and expansion of the SSE after a $M_L=5.3$ earthquake likely triggering an increase in interface permeability. Historical earthquake swarms highlight the persistent structural control and recurrent nature of such slow slip events. Our observations provide insight into the interactions between slow slip and seismicity, suggesting they are controlled by creep on a fluid-infiltrated fault with fractally distributed asperities.
title Seismic swarms unveil the mechanisms driving shallow slow slip dynamics in the Copiapó ridge, Northern Chile
topic Geophysics
url https://arxiv.org/abs/2411.18490