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Chinese Science Bulletin

, Volume 45, Issue 8, pp 751–753 | Cite as

Inner core’s seismic anisotropy is related to its rotation

  • Bin Liu
  • Qunshan Zhang
  • Baoshan Wang
  • Rongshan Fu
  • H. Kern
  • T. Popp
Notes

Abstract

The inner core has a differential rotation relative to the crust and mantle, the relative linear velocity between the solid inner core and the molten outer core is the biggest at the equator and zero at pole area. As a result, the inner core grows faster at the equator than at the pole area. The gravitational force drives the material flow from the equator to the pole area and makes the inner core remain quasi-orbicular. The corresponding axial symmetric stress field makesc-axes of hexagonal close packed (hcp) iron align with inner core’s rotation axis, resulting in observed seismic anisotropy.

Keywords

inner core growth rotation viscous flow preferred crystal orientation anisotropy 

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Copyright information

© Science in China Press 2000

Authors and Affiliations

  • Bin Liu
    • 1
  • Qunshan Zhang
    • 1
  • Baoshan Wang
    • 1
  • Rongshan Fu
    • 1
  • H. Kern
    • 2
  • T. Popp
    • 2
  1. 1.Department of Earth and Space ScienceUniversity of Science and Technology of ChinaHefeiChina
  2. 2.Mineralogisch-Petrographisches InstitutUniversität KielKielGermany

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