title: Earthquake dynamics. Mapping pressurized volcanic fluids from induced crustal seismic velocity drops.
abstract: Volcanic eruptions are caused by the release of pressure that has accumulated due to hot volcanic fluids at depth. Here, we show that the extent of the regions affected by pressurized fluids can be imaged through the measurement of their response to transient stress perturbations. We used records of seismic noise from the Japanese Hi-net seismic network to measure the crustal seismic velocity changes below volcanic regions caused by the 2011 moment magnitude (M(w)) 9.0 Tohoku-Oki earthquake. We interpret coseismic crustal seismic velocity reductions as related to the mechanical weakening of the pressurized crust by the dynamic stress associated with the seismic waves. We suggest, therefore, that mapping seismic velocity susceptibility to dynamic stress perturbations can be used for the imaging and characterization of volcanic systems.
authors.affiliation: Institut des Sciences de la Terre, Université Joseph Fourier, CNRS, F-38041 Grenoble, France. florent.brenguier@ujf-grenoble.fr.
authors.forename: F
authors.initials: F
authors.lastname: Brenguier
authors.affiliation: Institut des Sciences de la Terre, Université Joseph Fourier, CNRS, F-38041 Grenoble, France.
authors.forename: M
authors.initials: M
authors.lastname: Campillo
authors.affiliation: National Research Institute for Earth Science and Disaster Prevention, Tsukuba, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Takeda
authors.affiliation: Earthquake Research Institute, University of Tokyo, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Aoki
authors.affiliation: Institut de Physique du Globe de Paris, Sorbonne Paris Cité, CNRS (UMR7154), 75238 Paris Cedex 5, France.
authors.forename: N M
authors.initials: NM
authors.lastname: Shapiro
authors.affiliation: Institut des Sciences de la Terre, Université Joseph Fourier, CNRS, F-38041 Grenoble, France.
authors.forename: X
authors.initials: X
authors.lastname: Briand
authors.affiliation: National Research Institute for Earth Science and Disaster Prevention, Tsukuba, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Emoto
authors.affiliation: Earthquake Research Institute, University of Tokyo, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Miyake
mesh_terms: D055866:Earthquakes; D011312:Pressure; D018707:Volcanic Eruptions