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pure and applied geophysics

, Volume 132, Issue 1–2, pp 151–173 | Cite as

Inhomogeneities near the core-mantle boundary evidenced from scattered waves: A review

  • K. Bataille
  • R. S. Wu
  • S. M. Flatté
Article

Abstract

Statistical properties of small-scale inhomogeneities (wavelengths between 20 and 70 km) near the core-mantle boundary are inferred from scattered core waves. Observations of scattered core waves at large seismic arrays and worldwide networks indicate that the inhomogeneities have a global nature with similar characteristics. However, there may exist a few regions having markedly stronger or weaker strengths. Scattering by volumetric inhomogeneities of about 1% inP-wave velocity in the lower mantle or by about 300 m of topographic relief of the core-mantle boundary can explain the observations. At present it is not possible to rule out either of these two alternatives, or a combination of both.

Key words

Scattering wave propagation seismic waves core-mantle topography inhomogeneities 

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Copyright information

© Birkhäuser Verlag 1990

Authors and Affiliations

  • K. Bataille
    • 1
  • R. S. Wu
    • 1
  • S. M. Flatté
    • 1
  1. 1.Physics Department and Institute of TectonicsUniversity of CaliforniaSanta CruzUSA

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