Physics and Chemistry of Minerals

, Volume 16, Issue 5, pp 436–441

Raman microprobe study of synthetic diaplectic plagioclase feldspars


  • B. Velde
    • Laboratoire de Geologie, ER 224 CNRS, École Normale Superieure
  • Y. Syono
    • Institute for Materials Research, Tohoku University
  • M. Kikuchi
    • Institute for Materials Research, Tohoku University
  • H. Boyer
    • Instruments SA, Jobin Yvon

DOI: 10.1007/BF00197013

Cite this article as:
Velde, B., Syono, Y., Kikuchi, M. et al. Phys Chem Minerals (1989) 16: 436. doi:10.1007/BF00197013


Raman microprobe spectra were made on three post shock, diaplectic plagioclase feldspars. Optical and X-ray diffraction studies indicated that feldspars maintained a partially or totally crystalline state after having passed through the mixed phase zone of Hugoniot response to shock waves (15–38 GPa). The appearance of uniquely glass-type spectra occurs at different shock pressures for each specimen according to its atomic structural arrangement, below 38 GPa for mosaic structured labradorite, near 40 GPa for anorthite and above 50 GPa for the highly ordered low albite. The diaplectic anorthite and labradorite glasses give spectra which indicate the presence of two glass types. Shifts in the band envelope frequencies compared to spectra of fused glass and statically pressure densified glass suggest that these glasses have specific structural arrangements. These differences suggest that the shock and fusion glass-forming processes are not exactly identical.

The results from material shocked in the mixed phase region of Hugoniot response show that the phase transitions are effected at different pressures depending upon the feldspar structural type.

Download to read the full article text

Copyright information

© Springer-Verlag 1989