1IPGP - Institut de Physique du Globe de Paris (IPGP, 1 rue Jussieu, 75238 Paris cedex 05 ; Université Paris Diderot, Bât. Lamarck A case postale 7011, 75205 Paris CEDEX 13 - France)
Abstract : We present a new upper-mantle tomographic model derived solely from hum seismic data. Phase correlograms between station pairs are computed to extract phase-coherent signals. Correlograms are then stacked using the time-frequency phase-weighted stack method to build-up empirical Green's functions. Group velocities and uncertainties are measured in the wide period band of 30-250 s, following a resampling approach. Less data are required to extract reliable group velocities at short periods than at long periods, and 2 yr of data are necessary to measure reliable group velocities for the entire period band. Group velocities are first regionalized and then inverted versus depth using a simulated annealing method in which the number and shape of splines that describes the S-wave velocity model are variable. The new S-wave velocity tomographic model is well correlated with models derived from earthquakes in most areas, although in India, the Dharwar craton is shallower than in other published models.
https://hal-insu.archives-ouvertes.fr/insu-03581680 Contributor : Nathalie PothierConnect in order to contact the contributor Submitted on : Sunday, February 20, 2022 - 12:19:33 PM Last modification on : Wednesday, March 30, 2022 - 8:06:02 PM
A. Haned, E. Stutzmann, M. Schimmel, S. Kiselev, A. Davaille, et al.. Global tomography using seismic hum. Geophysical Journal International, Oxford University Press (OUP), 2016, 204, pp.1222-1236. ⟨10.1093/gji/ggv516⟩. ⟨insu-03581680⟩