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Source estimation for wavefield-reconstruction inversion

Authors:

Source estimation is essential for all wave-equation-based seismic inversions, including full-waveform inversion (FWI) and the recently proposed wavefield-reconstruction inversion (WRI). When the source estimation is inaccurate, errors will propagate into the predicted data and introduce additional data misfit. As a consequence, inversion results that minimize this data misfit may become erroneous. To mitigate the errors introduced by the incorrect and preestimated sources, an embedded procedure that updates sources along with medium parameters is necessary for the inversion. So far, such a procedure is still missing in the context of WRI, a method that is, in many situations, less prone to local minima related to so-called cycle skipping, compared with FWI through exact data fitting. Although WRI indeed helps to mitigate issues related to cycle skipping by extending the search space with wavefields as auxiliary variables, it relies on having access to the correct source functions. To remove the requirement of having the accurate source functions, we have developed a source-estimation technique specifically designed for WRI. To achieve this task, we consider the source functions as unknown variables and arrive at an objective function that depends on the medium parameters, wavefields, and source functions. During each iteration, we apply the so-called variable projection method to simultaneously project out the source functions and wavefields. After the projection, we obtain a reduced objective function that only depends on the medium parameters and invert for the unknown medium parameters by minimizing this reduced objective. Numerical experiments illustrate that this approach can produce accurate estimates of the unknown medium parameters without any prior information of the source functions.

REFERENCES

  • Akcelik, V., 2002, Multiscale Newton-Krylov methods for inverse acoustic wave propagation: Ph.D. thesis, Carnegie Mellon University.
  • Amestoy, P., R. Brossier, A. Buttari, J.-Y. L’Excellent, T. Mary, L. Metivier, A. Miniussi, and S. Operto, 2016, Fast 3D frequency-domain full-waveform inversion with a parallel block low-rank multifrontal direct solver: Application to OBC data from the North Sea: Geophysics, 81, no. 6, R363–R383, doi: 10.1190/geo2016-0052.1.GPYSA70016-8033
  • Aravkin, A. Y., and T. van Leeuwen, 2012, Estimating nuisance parameters in inverse problems: Inverse Problems, 28, 115016, doi: 10.1088/0266-5611/28/11/115016.INPEEY0266-5611
  • Askan, A., V. Akcelik, J. Bielak, and O. Ghattas, 2007, Full waveform inversion for seismic velocity and anelastic losses in heterogeneous structures: Bulletin of the Seismological Society of America, 97, 1990–2008, doi: 10.1785/0120070079.BSSAAP0037-1106
  • Bernstein, D. S., 2005, Matrix mathematics: Theory, facts, and formulas with application to linear systems theory: Princeton University Press.
  • Brossier, R., S. Operto, and J. Virieux, 2009, Seismic imaging of complex onshore structures by 2D elastic frequency-domain full-waveform inversion: Geophysics, 74, no. 6, WCC105–WCC118, doi: 10.1190/1.3215771.GPYSA70016-8033
  • Chen, Z., D. Cheng, W. Feng, and T. Wu, 2013, An optimal 9-point finite difference scheme for the Helmholtz equation with PML: International Journal of Numerical Analysis and Modeling, 10, 389–410.
  • Golub, G., and V. Pereyra, 2003, Separable nonlinear least squares: The variable projection method and its applications: Inverse Problems, 19, R1–R26, doi: 10.1088/0266-5611/19/2/201.INPEEY0266-5611
  • Huang, G., R. Nammour, and W. Symes, 2017, Full-waveform inversion via source-receiver extension: Geophysics, 82, no. 3, R153–R171, doi: 10.1190/geo2016-0301.1.GPYSA70016-8033
  • Li, M., J. Rickett, and A. Abubakar, 2013, Application of the variable projection scheme for frequency-domain full-waveform inversion: Geophysics, 78, no. 6, R249–R257, doi: 10.1190/geo2012-0351.1.GPYSA70016-8033
  • Li, X., A. Y. Aravkin, T. van Leeuwen, and F. J. Herrmann, 2012, Fast randomized full-waveform inversion with compressive sensing: Geophysics, 77, no. 3, A13–A17, doi: 10.1190/geo2011-0410.1.GPYSA70016-8033
  • Liu, J., A. Abubakar, T. Habashy, D. Alumbaugh, E. Nichols, and G. Gao, 2008, Nonlinear inversion approaches for cross-well electromagnetic data collected in cased-wells: 78th Annual International Meeting, SEG, Expanded Abstracts, 304–308.
  • Nocedal, J., and S. J. Wright, 2006, Numerical optimization: Springer-Verlag.
  • Peters, B., C. Greif, and F. J. Herrmann, 2015, An algorithm for solving least-squares problems with a Helmholtz block and multiple right-hand-sides: Presented at the International Conference on Preconditioning Techniques for Scientific and Industrial Applications.
  • Peters, B., and F. J. Herrmann, 2017, Constraints versus penalties for edge-preserving full-waveform inversion: The Leading Edge, 36, 94–100, doi: 10.1190/tle36010094.1.
  • Peters, B., F. J. Herrmann, and T. van Leeuwen, 2014, Wave-equation based inversion with the penalty method: Adjoint-state versus wavefield-reconstruction inversion: 76th Annual International Conference and Exhibition, EAGE, Extended Abstracts, doi: 10.3997/2214-4609.20140704.
  • Plessix, R.-E., 2006, A review of the adjoint-state method for computing the gradient of a functional with geophysical applications: Geophysical Journal International, 167, 495–503, doi: 10.1111/j.1365-246X.2006.02978.x.GJINEA0956-540X
  • Pratt, R. G., 1999, Seismic waveform inversion in the frequency domain. Part 1: Theory and verification in a physical scale model: Geophysics, 64, 888–901, doi: 10.1190/1.1444597.GPYSA70016-8033
  • Symes, W. W., D. Sun, and M. Enriquez, 2011, From modeling to inversion: Designing a well-adapted simulator: Geophysical Prospecting, 59, 814–833, doi: 10.1111/j.1365-2478.2011.00977.x.GPPRAR0016-8025
  • Tarantola, A., and B. Valette, 1982, Generalized nonlinear inverse problems solved using the least squares criterion: Reviews of Geophysics, 20, 219–232, doi: 10.1029/RG020i002p00219.REGEEP8755-1209
  • van Leeuwen, T., A. Y. Aravkin, and F. J. Herrmann, 2014, Comment on: “Application of the variable projection scheme for frequency-domain full-waveform inversion” (M. Li, J. Rickett, and A. Abubakar, Geophysics, 78, no. 6, R249–R257): Geophysics, 79, no. 3, X11–X17, doi: 10.1190/geo2013-0466.1.GPYSA70016-8033
  • van Leeuwen, T., and F. J. Herrmann, 2013a, Fast waveform inversion without source encoding: Geophysical Prospecting, 61, 10–19, doi: 10.1111/j.1365-2478.2012.01096.x.GPPRAR0016-8025
  • van Leeuwen, T., and F. J. Herrmann, 2013b, Mitigating local minima in full-waveform inversion by expanding the search space: Geophysical Journal International, 195, 661–667, doi: 10.1093/gji/ggt258.GJINEA0956-540X
  • van Leeuwen, T., and F. J. Herrmann, 2015, A penalty method for PDE-constrained optimization in inverse problems: Inverse Problems, 32, 015007, doi: 10.1088/0266-5611/32/1/015007.INPEEY0266-5611
  • Virieux, J., and S. Operto, 2009, An overview of full-waveform inversion in exploration geophysics: Geophysics, 74, no. 6, WCC1–WCC26, doi: 10.1190/1.3238367.GPYSA70016-8033
  • Warner, M., T. Nangoo, N. Shah, A. Umpleby, and J. Morgan, 2013, Full-waveform inversion of cycle-skipped seismic data by frequency down-shifting: 83rd Annual International Meeting, SEG, Expanded Abstracts, 903–907.
  • Zhou, B., and S. A. Greenhalgh, 2003, Crosshole seismic inversion with normalized full-waveform amplitude data: Geophysics, 68, 1320–1330, doi: 10.1190/1.1598125.GPYSA70016-8033