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Pyroclastic rocks in the Cnapan Breaca felsite, Rhum

Published online by Cambridge University Press:  01 May 2009

P. J. Williams
P. J. Williams
Affiliation:
Geology Department, University of London Goldsmiths' College, Rachel McMillan Building, Creek Road, London SE8 3BU
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Abstract

The Cnapan Breaca felsite sheet contains strongly devitrified pyroclastic rocks including welded tuffs. These indicate formation in a high level, surficial or sub-volcanic environment. The gross structure and lithological associations of the sheet are similar to those of some ignimbrites. These observations support a resurgent caldera model for the evolution of the Rhum centre and raise some doubts about previous interpretations of the felsite-breccia association on the island.

Type
Articles
Information
Geological Magazine , Volume 122 , Issue 5 , September 1985 , pp. 447 - 450
Copyright
Copyright © Cambridge University Press 1985

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