Skip to Main content Skip to Navigation
Journal articles

Source depopulation potential and surface-wave tomography using a crosscorrelation method in a scattering medium

Pierre Gouédard 1, 2 Philippe Roux 3 Michel Campillo 3 Arie Verdel 4, 5 Huajian Yao 1 Robert D. van der Hilst 1
1 EAPS - Department of Earth, Atmospheric and Planetary Sciences [MIT, Cambridge]
2 ISTerre - Institut des Sciences de la Terre
3 Ondes et Structures
ISTerre - Institut des Sciences de la Terre
4 Shell International Exploration and Production
5 Department of Geotechnology
Abstract : We use seismic prospecting data on a regular grid of sources and receivers deployed on a area to assess the feasibility and advantages of velocity analysis of the shallow subsurface by means of surface wave tomography with Green's functions estimated from crosscorrelation. In a first application we measure Rayleigh-wave dispersion curves in a 1D equivalent medium. The assumption that the medium is laterally homogeneous allows using a simple projection scheme and averaging of crosscorrelation functions over the whole network. Because averaging suppresses noise, this method yields better signal-to-noise ratio than traditional active-source approaches, and the improvement can be estimated a priori from acquisition parameters. We find that high-quality dispersion curves can be obtained even when we reduce the number of active sources used as inputs for the correlations. Such source depopulation can achieve significant reduction in the cost of active source acquisition. In a second application we compare Rayleigh-wave group velocity tomography from raw and reconstructed data. We demonstrate that the crosscorrelation approach yields group velocity maps that are similar to active source maps. Scattering has an importance here as it may enhance the crosscorrelation performance. We quantify the scattering properties of the medium using mean free path measurements from coherent and incoherent parts of the signal. We conclude that for first-order velocity analysis of the shallow subsurface, the use of crosscorrelation offers a cost-effective alternative to methods that rely exclusively on active sources.
Document type :
Journal articles
Complete list of metadatas
https://hal-insu.archives-ouvertes.fr/insu-00680369
Contributor : Pascale Talour <>
Submitted on : Monday, March 19, 2012 - 12:30:28 PM
Last modification on : Tuesday, December 8, 2020 - 10:21:04 AM

Identifiers

Collections

INSU | CNRS | UNIV-SAVOIE | OSUG | IFSTTAR | ISTERRE | UGA

Citation

Pierre Gouédard, Philippe Roux, Michel Campillo, Arie Verdel, Huajian Yao, et al.. Source depopulation potential and surface-wave tomography using a crosscorrelation method in a scattering medium. Geophysics, Society of Exploration Geophysicists, 2011, 76 (2), pp.SA51-SA61. ⟨10.1190/1.3535443⟩. ⟨insu-00680369⟩

Export

BibTeX TEI DC DCterms EndNote

Share

Metrics

Record views

376