HR: 0800h
AN: S41A-0229 [Abstracts]
TI: Tomography of the Alps using seismic ambient noise
AU: * Stehly, L
EM: lstehly@obs.ujf-grenoble.fr
AF: LGIT Grenoble, 1381, rue de la Piscine, Grenoble, 38000, France
AU: * Stehly, L
EM: lstehly@obs.ujf-grenoble.fr
AF: CEA/DASE, BP 12, Bruyeres-le-Châtel, 91680, France
AU: Bill, F
EM: bill.fry@tomo.ig.erdw.ethz.ch
AF: Institute of Geophysics,
ETH Zurich, ETH-Hoenggerberg, Zurich, 8093, Switzerland
AU: Campillo, M
EM: campillo@obs.ujf-grenoble.fr
AF: LGIT Grenoble, 1381, rue de la Piscine, Grenoble, 38000, France
AU: Shapiro, N
EM: nshapiro@ipgp.jussieu.fr
AF: Laboratoire de Sismologie, IPGP, 4, place Jussieu, Paris, 75252, France
AU: Guilbert, J
EM: guilbert@cea.fr
AF: CEA/DASE, BP 12, Bruyeres-le-Châtel, 91680, France
AU: Boschi, L
EM: larryboschi@gmail.com
AF: Institute of Geophysics,
ETH Zurich, ETH-Hoenggerberg, Zurich, 8093, Switzerland
AU: Giardini, D
EM: d.giardini@sed.ethz.ch
AF: Institute of Geophysics,
ETH Zurich, ETH-Hoenggerberg, Zurich, 8093, Switzerland
AB:
We use seismic ambient noise correlation to study the lithosphere in western Europe. Cross correlation of one
year of noise recorded at 150 3-components broadband stations yields more than 3000 Rayleigh and Love wave
group velocity measurements. These measurements are used to construct Rayleigh and Love group velocity
models of the Alpine region and surrounding area in the 5-50s period band.
The seismic noise recorded in Europe is dominated by noise originating from the Northern Atlantic ocean. This
anisotropy of the noise and the uneven station distribution affect the azimuthal distribution of the paths where we
obtain reliable group velocity measurements. As a consequence our group velocity models have better resolution
in the South-East direction than in the North-West direction. Finally we invert
the resulting Rayleigh wave group velocity maps to determine the Moho depth. Our results are in good agreement
with the result of the numerous active experiments in the Alps.
DE: 7205 Continental crust (1219)
DE: 7255 Surface waves and free oscillations
DE: 7270 Tomography (6982, 8180)
SC: Seismology [S]
MN: 2007 Fall Meeting