An Approach to Analyzing Diffusion in Olivine

  1. Robert N. Schock
  1. Ralph. H. Condit

Published Online: 18 MAR 2013

DOI: 10.1029/GM031p0106

Point Defects in Minerals

Point Defects in Minerals

How to Cite

Condit, Ralph. H. (1985) An Approach to Analyzing Diffusion in Olivine, in Point Defects in Minerals (ed R. N. Schock), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM031p0106

Author Information

  1. Lawrence Livermore National Laboratory Livermore, California 94550

Publication History

  1. Published Online: 18 MAR 2013
  2. Published Print: 1 JAN 1985

ISBN Information

Print ISBN: 9780875900568

Online ISBN: 9781118664070

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Keywords:

  • Mineralogical chemistry—Congresses;
  • Crystals—Defects—Congresses

Summary

Olivine is pictured as a hexagonal close packing of oxygen ions which provide a matrix for cation diffusion. The network of paths which a cation may take when jumping between normal and interstitial sites is described, and an approach to the analysis of diffusion in this network is suggested. In intermediate diffusion configurations several point defects may be generated which have preferred distances and orientations relative to one another. A succession of these configurations then lead to a final one with the migrating atom in a new site. It is proposed that oxygen diffusion may be by cation-anion divacancies. Two published sets of data on silicon diffusion coefficients differ by four orders of magnitude and it is suggested that this may result from differences in dissolved silica. Measurement of correlation coefficients would make an important contribution to determining actual mechanisms of cation and silicon diffusion.