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The quartz-plagioclase gneisses of Western Connemara, Ireland

Published online by Cambridge University Press:  01 May 2009

R. E. K. Benjamin
Affiliation:
Warren Spring Laboratory, Gunnels Wood Road, Stevenage, Herts.

Summary

Chemical analysis of twenty-six amphibolite facies gneisses from western Connemara are treated statistically, and used in conjunction with petrographic evidence to elucidate their origins. It is shown that the gneisses are of igneous ancestry, and have been invaded by material of silica-soda potash composition. The conditions of temperature and pressure prevailing at different times is related to the evolved mineral assemblages, and the whole sequence fitted into the general pattern of events in Connemara.

Type
Articles
Copyright
Copyright © Cambridge University Press 1968

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References

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