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Isotopic age data from Scourian intrusive rocks on the Isle of Barra, Outer Hebrides, north-west Scotland

Published online by Cambridge University Press:  01 May 2009

P. W. Francis ,
S. Moorbath  and
H. J. Welke
P. W. Francis
Affiliation:
Department of Geology, Imperial College, London
S. Moorbath
Affiliation:
Department of Geology, Oxford University
H. J. Welke
Affiliation:
Department of Geology, Oxford University
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Summary

Rubidium–strontium and potassium–argon measurements on Lewisian intrusive rocks, considered to be late Scourian in age on general geological grounds, have indeed yielded dates in the range 2450–2600 m.y. This demonstrates that rocks of Scourian age that have escaped substantial Laxfordian reworking are preserved in the Eastern Gneisses of Barra. The relevant geological consequences and correlations are briefly discussed. A cross-cutting late pegmatite yields a typical Laxfordian date of 1679 m.y.

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Type
Articles
Information
Geological Magazine , Volume 108 , Issue 1 , January 1971 , pp. 13 - 21
Copyright
Copyright © Cambridge University Press 1971

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