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The origin of cordierite—anthophllite rocks in the Land's End aureole

Published online by Cambridge University Press:  01 May 2009

G. A. Chinner
Affiliation:
Department of Mineralogy and Petrology, Downing Place, Cambridge
J. S. Fox
Affiliation:
Department of Mineralogy and Petrology, Downing Place, Cambridge

Summary

The prevalence of low-variance assemblages, the frequency of the buffered association anthophyllite—cordierite—cummingtonite—plagioclase, and the ubiquity of aluminium-rich clots of diaspore incompatible with the ortho-amphibole of the rock suggest that the cordierite—anthophyllite rocks of the Land's End aureole are not the product of metasomatism, but resulted from the thermal metamorphism of pre-existing rock-compositions. The origin of many kyanite-, amphibole- and cordierite-rich bodies by pre-metamorphic alteration is of economic significance in regions where such curious silicate assemblages accompany sulphide deposits.

Type
Articles
Copyright
Copyright © Cambridge University Press 1974

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