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Quartz Fabric Reorientation in the Region of Benmore Assynt, North-West Highlands of Scotland

Published online by Cambridge University Press:  01 May 2009

C. B. Crampton
Affiliation:
152 Heol Llanishen Fach, Rhiwbina, Cardiff, Wales.

Abstract

In the Assynt area of the North-West Highlands of Scotland a regional preferred orientation of quartz [0001]-axes of sedimentary origin in Cambrian quartzites has withstood considerable deformation and destroyed only with the onset of granulation in the immediate vicinity of thrust planes. After partial granulation the remaining scattered quartz grains develop a preferred orientation of [0001]-axes quite distinct from the sedimentary fabric. Recrystallization is apparent well away from the thrust planes, but only supersedes granulation along certain sections of the major Moine Thrust plane. The preferred orientation of quartz [0001]-axes in these recrystallized fabrics is somewhat variable. The regional quartz fabric of metamorphic origin in Moine rocks immediately above the thrust planes can experience a similar deformation, recrystallization following granulation with the development of quartz fabrics similar to those in recrystallized quartzites below the Moine Thrust plane.

Type
Articles
Copyright
Copyright © Cambridge University Press 1963

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References

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