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Widespread secondary Ca garnet and other Ca silicates in the Galway Granite and its satellite plutons caused by fluid movements, western Ireland

Published online by Cambridge University Press:  05 July 2018

Bernard E. Leake*
Affiliation:
Department of Earth Sciences, Cardiff University, PO Box 914, Cardiff CF1 3YE

Abstract

Widespread secondary andradite-grossular-hydrogrossular garnet, epidote, prehnite and titanite occur throughout the Galway Granite and its satellite plutons (Roundstone; Inish; Omey and Letterfrack) and even in some of the country rocks several kilometres from the granites. These minerals are not found in low CaO (<1%) granites. They formed as result of secondary fluid movements which altered the biotite, plagioclase and hornblende and also produced sericite and chlorite.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1998

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