rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Numerical Simulation of Seismic Wave Propagation in the Presence of Complex Near-Surface Heterogeneity Including Surface Topography
  name:
    name part: Son, Jungrak
    role:
      role term: creator
    role:
      role term: author.
  name:
    name part: Gibson, Richard L.
    role:
      role term: thesis advisor.
  name:
    name part: Duan, Benchun
    role:
      role term: thesis advisor.
  name:
    name part: Texas A & M University
    role:
      role term: degree granting institution.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: txu
    date issued: 2015
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: remote
    extent: 1 online resource.
  abstract: Surface wave analysis and inversion have been developed to improve P-wave imaging for hydrocarbon reservoirs in land environments. This requires elastic wave modeling validation based on an accurate near-surface geology model. However, conventional modeling approaches with uniform grids pose significant challenges to represent complex geometry of near-surface heterogeneities and irregular surface topography. To solve this issue, numerical simulation of elastic wave propagation is implemented based on the spectral-element method, which is ideal for applying flexible unstructured grids. Locally-refined hybrid grids are used to describe the complex boundaries of subsurface structures, and refined grids are effective to reduce computational costs. Three representative examples of geological features as near-surface heterogeneities are analyzed in seismic modeling with synthetic earth models. The structures are a shallow small scatterer, a collapsed karst structure and a low-velocity top layer with surface topography. The earth model geometry and material properties are based on the data from the recently released SEAM 2 project "arid model." The resulting seismograms show that scattered surface waves from the shallow velocity anomalies are affected by the shape of modeling grids, properties of filling materials, attenuation, and curved surface topography. Specifically, the shallow scatterer, which is filled with low-velocity materials, shows a significant amount of trapped seismic energy and generates multiple scattered surface waves. These unwanted waves from trapped energy are strongly based on the surface topography and attenuation factor, Q. Since scattered surface waves are sensitively affected by various geological features and modeling factors, advanced seismic forward modeling approaches should be used for the accurate near-surface modeling. This study shows the capability and potential of the spectral-element method with advanced conforming grids to handle high…
  note: by Jungrak Son.
  note: "Major Subject: Geophysics"
  note: Includes vita.
  note: Master of Science Texas A & M University 2015 http://hdl.handle.net/1969.1/155570
  note: Includes bibliographical references.
  note: Text (Thesis)
  subject:
    topic: Major Geophysics
  subject:
    topic: Elastic wave
  subject:
    topic: Heterogeneity
  subject:
    topic: Topography
  identifier: http://hdl.handle.net/1969.1/155570
  record info:
    record content source: TXA
    record creation date: 161007
    record change date: 20170926145814.0
    record identifier: in00003717208
    language of cataloging:
      language term: eng