Multicomponent Rayleigh-wave crosscorrelation waveform inversion for ambient seismic sources

15 Novembre 2019, ISTerre Grenoble

**Séminaire de l’équipe Ondes et structures

par Zongbo Xu, Ph.D. candidate from Boise State University

– Date

15 Novembre 2019 à 11h00

– Lieu

Salle Dolomieu, ISTerre Grenoble

Abstract :

Ambient seismic source information is important for subsurface investigations and source studies. Crosscorrelation-based seismic interferometry is commonly used to retrieve surface-wave Green’s functions from ambient seismic noise recordings. This approach requires that seismic sources are isotropically distributed in all directions around two receivers. However, this assumption is rarely valid in practice. If one combines the source information (like locations and strengths) with the seismic interferometry, one can still accurately estimate structure information. The distributions of some ambient seismic sources (e.g. microseisms) change with time and thus attract lots of research interests. We present an approach to estimate spatially distributed ambient seismic sources by inversion of seismic wavefield noise crosscorrelations. We demonstrate the benefits of using multicomponent crosscorrelations in this source estimation process. We present a shallow near-surface case study and a preliminary estimation of the Antarctic primary microseism in February 2010.