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Terminology of postcumulus processes and products in the Rhum layered intrusion

Published online by Cambridge University Press:  01 May 2009

W. J. Wadsworth
Affiliation:
Department of Geology, The University, Manchester, M13 9PL

Abstract

The terminology of cumulates is discussed with particular reference to postcumulus processes as exemplified by the Rhum layered intrusion. The history of the terms orthocumulate, adcumulate, heteradcumulate and harrisitic cumulate is reviewed, and some modifications to the classification scheme proposed by Irvine (1982) are suggested. Possible mechanisms of adcumulus growth are considered and, on balance, the Rhum evidence confirms the view that postcumulus cementation occurred at a relatively early stage, while the intercumulus melt was in effective contact with the main body of magma.

Type
Articles
Copyright
Copyright © Cambridge University Press 1985

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