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Disequilibrium textures in the Leinster Granite Complex, SE Ireland: evidence for acid-acid magma mixing

Published online by Cambridge University Press:  05 July 2018

S. E. Grogan  and
R. J. Reavy
S. E. Grogan
Affiliation:
Department of Geology, National University of Ireland, Cork, Ireland
R. J. Reavy
Affiliation:
Department of Geology, National University of Ireland, Cork, Ireland
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Abstract

The LGC (Leinster Granite Complex) in SE Ireland consists of five plutons or Units. Units 1 and 3 display complex magmatic disequilibrium textures described here for the first time. The textures indicative of disequilibrium include boxy cellular plagioclase, oscillatory zoning, calcic spike zones and combinations of these within individual plagioclase feldspar crystals. The textures are interpreted as having formed in a dynamic magmatic environment which facilitated acid-acid mixing on a variety of scales and at a variety of stages between source to emplacement. It is proposed that the restricted distribution of disequilibrium textures was a result of the complex strain regime operating within the crust during assembly of Units 1 and 3.

Keywords

graniteLeinsterSE Irelandmagma mixingdisequilibriummicrotextures
Type
Research Article
Information
Mineralogical Magazine , Volume 66 , Issue 6 , December 2002 , pp. 929 - 939
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2002

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