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Origin of the White Allivalite, Western Cuillin, Isle of Skye

Published online by Cambridge University Press:  01 May 2009

Robert Hutchison
Affiliation:
Department of Earth Sciences, The University, Leeds 2.

Summary

Tholeiitic contact rocks and a wide zone (White Allivalite) rich in primary precipitate calcic plagioclase are marginal to a layered allivalite series in a funnel-shaped intrusion. The high structural level apparently precludes the possibility that the ultrabasic layered rocks are the basal part of an accumulate from a tholeiitic magma. It is suggested, therefore, that a suspension of calcic plagioclase in a liquid more basic than basalt gave rise to an approximately equal volume of layered ultrabasic rocks by fractional crystallization. Emplacement was probably initiated as a tholeiitic cone-sheet complex, followed by the injection of the ultrabasic suspension in a volume sufficiently large to form a funnel-shaped body within the cone-sheet complex.

Type
Articles
Copyright
Copyright © Cambridge University Press 1968

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References

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