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Hercynian Fe-Mg Metasomatism in Cornwall: A Reinterpretation

Published online by Cambridge University Press:  01 May 2009

Doris L. Reynolds
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Extract

In connection with a recent investigation of the geochemical changes leading up to granitization, the writer (Reynolds, 1946) had occasion to plot the chemical analyses of the rocks of the Kenidjack and Botallack region, Cornwall (Tilley and Flett, 1930; Tilley, 1935) on a von Wolff diagram. Since the diagram required somewhat lengthy discussion, however, it was not included in the geochemical paper. The diagram is nevertheless of interest because it presents in a new form the problem of the genetic associations of these curious rocks, characterized as they are by anthophyllite, cummingtonite, cordierite, and grunerite, and provides useful hints which might form a basis for further field investigations in Cornwall. The present paper, offering tentative interpretations of some of the Cornish rocks, is written in the hope of focusing attention on the petrogenetic significance of this region, and thus of stimulating detailed investigations, with strict correlation between field observations and chemical analyses, by which means alone the problems presented can be solved.

Type
Articles
Information
Geological Magazine , Volume 84 , Issue 1 , February 1947 , pp. 33 - 50
Copyright
Copyright © Cambridge University Press 1947

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