1887

Abstract

Summary

We estimate the elastic properties of marine sediments beneath the seabed by means of high-resolution velocity analysis and 1D elastic full-waveform inversion (FWI) performed on 2D seismic data of a well-site survey (WSS). A high-resolution velocity functional is employed to exploit the broad frequency band of the WSS data and to derive the compressional velocity field with a high degree of accuracy. The estimated velocity field is then used as a priori information in the 1D elastic FWI that is solved by making use of genetic algorithms as optimization method. We consider two error functions: the first uses the entire waveform to compute the misfit between modelled and observed seismograms; the second considers the envelope of the seismograms thus relaxing the requirement of an exact estimation of the wavelet phase. The very similar velocities and density depth trends derived in the two FWI tests indicate the reliability of the predicted subsurface model. Moreover, the FWI and the high-resolution velocity analysis yield comparable velocity profiles, although with different resolution.

Loading

Article metrics loading...

/content/papers/10.3997/2214-4609.201413804
2015-09-06
2024-04-23
Loading full text...

Full text loading...

References

  1. Aleardi, M., and Mazzotti, A.
    [2014] 1D Elastic FWI and Uncertainty Estimation by Means of a Hybrid Genetic Algorithm-Gibbs Sampler Approach. 76th EAGE Conference and Exhibition 2014. DOI: 10.3997/2214‑4609.20140858
    https://doi.org/10.3997/2214-4609.20140858 [Google Scholar]
  2. Key, S.C. and Smithson, S.B.
    [1990] New approach to seismic-reflection event detection and velocity determination. Geophysics, 55(8), 1057–1069.
    [Google Scholar]
  3. Sajeva, A., Aleardi, M., Mazzotti, A., Stucchi, E. and Galuzzi, B.
    [2014] Comparison of Stochastic Optimization Methods on Two Analytic Objective Functions and on a 1D Elastic FWI. 76th EAGE Conference and Exhibition 2014. DOI: 10.3997/2214‑4609.20140857
    https://doi.org/10.3997/2214-4609.20140857 [Google Scholar]
  4. Tognarelli, A., Stucchi, E., Ravasio, A. and Mazzotti, A.
    [2013] High-resolution coherency functionals for velocity analysis: An application for subbasalt seismic exploration. Geophysics, 78(5), U53–U63.
    [Google Scholar]
  5. Tognarelli, A., Stucchi, E.M., Bienati, N., Sajeva, A., Aleardi, M. and Mazzotti, A.
    [2015] Two grid stochastic Full Waveform Inversion of 2D Marine Seismic Data. 77th EAGE Conference and Exhibition 2015.
    [Google Scholar]
  6. Virieux, J. and Operto, S.
    [2009] An overview of full-waveform inversion in exploration geophysics. Geophysics, 74(6), WCC1–WCC26.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201413804
Loading
/content/papers/10.3997/2214-4609.201413804
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error