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On quartz-kyanite-rocks in Unst, Shetland Islands, and their bearing on metamorphic differentiation

Published online by Cambridge University Press:  14 March 2018

H. H. Read*
Affiliation:
University of Liverpool

Extract

Among the many beautiful rocks of Unst, the most northerly of the Shetlands, is one composed of rosettes of pale blue kyanite set in a base of glassy quartz. This rock was mentioned by Heddle, but has never been described, nor have its genetic relationships been considered. During the mapping of Unst for the Geological Survey, opportunity was afforded of examining the field-relations of these quartz-kyanite-rocks and of collecting adequate material for study. I am indebted to Sir John Flett, F.R.S., Director of the Survey, for permission to present this account. These rocks have a considerable intrinsic interest; in addition, their investigation is closely concerned with certain general problems in metamorphism, especially those connected with metamorphic differentiation. The present paper is therefore divided into two portions, the first dealing with the description and origin of the Unst rocks, and the second with more general aspects.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1933

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References

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