Misfit functions for full waveform inversion based on instantaneous phase and envelope measurements

Ebru Bozdaǧ, Jeannot Trampert, Jeroen Tromp

Research output: Contribution to journalArticle

180 Scopus citations

Abstract

Resolution in seismic tomography intimately depends on data coverage, with different parts of seismograms sensitive to different parts of Earth's structure. In classical seismic tomography, the usable amount of data is often restricted because of approximations to the wave equation. 3-D numerical simulations of wave propagation provide new opportunities for increasing the amount of usable data in seismograms by choosing appropriate misfit functions which have direct control on Fréchet derivatives. We propose new misfit functions for full waveform tomography based on instantaneous phase differences and envelope ratios between observed and synthetic seismograms. The aim is to extract as much information as possible from a single seismogram. Using the properties of the Hilbert transform, we separate phase and amplitude information in the time domain. To gain insight in the advantages and disadvantages of chosen misfit functions, we make qualitative comparisons of the corresponding finite-frequency adjoint sensitivity kernels with those from commonly used misfit functions based on cross-correlation traveltime, amplitude and waveform differences. The major advantages of our misfit functions are: (1) working in the Hilbert domain reduces non-linear behaviour of waveforms due to interaction of phase and amplitude information, and (2) we show with noise-free synthetic seismograms that it is possible to use a complete seismogram without losing information from low-amplitude phases. Complementary to instantaneous phase measurements, envelope measurements provide a way of using amplitude information of waveforms, which may also easily be extended to constrain anelastic properties. The properties of the kernels allow us to simplify the tomography problem by separating elastic and anelastic inversions. First indications are that the kernels remain well behaved in the presence of noise.

Original languageEnglish (US)
Pages (from-to)845-870
Number of pages26
JournalGeophysical Journal International
Volume185
Issue number2
DOIs
StatePublished - May 1 2011

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Geochemistry and Petrology

Keywords

  • Body waves
  • Computational seismology
  • Seismic tomography
  • Surface waves and free oscillations
  • Wave propagation

Fingerprint Dive into the research topics of 'Misfit functions for full waveform inversion based on instantaneous phase and envelope measurements'. Together they form a unique fingerprint.

  • Cite this