FastFind »   Lastname: doi:10.1029/ Year: Advanced Search  

AGU: Geophysical Research Letters

 

Keywords

  • stochastic tomography
  • l beam semblance
  • VFSA

Index Terms

  • Seismology: Tomography
  • Computational Geophysics: Data analysis: algorithms and implementation
  • Mathematical Geophysics: Inverse theory
  • Mathematical Geophysics: Uncertainty quantification
  • Seismology: General or miscellaneous

Abstract

GEOPHYSICAL RESEARCH LETTERS, VOL. 35, L23307, 5 PP., 2008
doi:10.1029/2008GL034776

First arrival stochastic tomography: Automatic background velocity estimation using beam semblances and VFSA

Chaoshun Hu

Institute for Geophysics and Department of Geological Sciences, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, Texas, USA

Paul Stoffa

Institute for Geophysics and Department of Geological Sciences, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, Texas, USA

Kirk McIntosh

Institute for Geophysics and Department of Geological Sciences, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, Texas, USA

We present a new tomography method based on the local beam semblance and the very fast simulated annealing (VFSA) global optimization method. The data space is the local beam semblance calculated using local slant stacks for overlapping offset windows, i.e. beam windows, of the original common-shot or common-receiver gathers. On each beam semblance panel, the first coherency peak can be identified with a particular ray parameter, first-arrival traveltime and beam center position. The forward problem can be solved with any ray tracer to find arrivals matching the identified peaks. Our inversion scheme uses VFSA to find the maximum-a-posteriori (MAP) solution and estimates the uncertainty by applying Bayesian analysis of all the sampled models for a specified model parameterization. This integration of automatic local semblance evaluation instead of first-arrival picking and a fast forward modeling method combined with VFSA to determine the optimal model makes our method robust, efficient and accurate.

Received 8 August 2008; accepted 20 October 2008; published 9 December 2008.

Citation: Hu, C., P. Stoffa, and K. McIntosh (2008), First arrival stochastic tomography: Automatic background velocity estimation using beam semblances and VFSA, Geophys. Res. Lett., 35, L23307, doi:10.1029/2008GL034776.

Cited By

Please wait one moment ...