Support for anisotropy of the Earth's inner core from free oscillations

  title={Support for anisotropy of the Earth's inner core from free oscillations},
  author={Jeroen Tromp},
  • J. Tromp
  • Published 1 December 1993
  • Geology
  • Nature
IN 1983, Poupinet et al.1 observed that compressional seismic waves traversing the inner core along a trajectory parallel to the Earth's rotation axis arrive faster than the same (PKIKP) waves travelling in the equatorial plane. They interpreted this observation as revealing prolate topography of the inner-core boundary. In 1986, Morelli et al.2 and Woodhouse et al.3 suggested that inner-core anisotropy could explain both the travel-time observations and the anomalous splitting of some of the… 

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