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Ground roll attenuation with least-squares and robust inversion

  • Author / Creator
    Papathanasaki, Iliana
  • This thesis proposes a framework for ground roll removal based on regularized inversion.
    Both ground roll and reflections are represented in the frequency-space (f - x) domain as
    a linear function of unknown complex amplitudes. An inversion algorithm is developed to estimate the coefficients that model the ground roll and reflections separately. The latter
    allows for an independent synthesis of ground roll and reflections. The synthesized ground
    roll is subtracted from the seismic records to yield a seismic record with enhanced reflections.
    In the first part of this thesis, a regularized least-squares inversion algorithm is proposed.
    I further propose to adopt two types of regularization to guarantee the stability of the
    inversion. To be more specific, I compare classical quadratic regulation with sparsity promoting
    regularization. Numerical experiments show that sparsity promoting regularization
    yields better results than quadratically regularized inversion. A robust regularized inversion
    algorithm is also proposed to cope with erratic noise often present in onshore data.
    Through synthetic and field data examples, we prove the effectiveness and the limitations
    of these algorithms.

  • Subjects / Keywords
  • Graduation date
    Fall 2020
  • Type of Item
    Thesis
  • Degree
    Master of Science
  • DOI
    https://doi.org/10.7939/r3-pr6v-x918
  • License
    Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.