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A note on the age and pyroxene chemistry of the igneous rocks of the Shelve Inlier, Welsh Borderland

Published online by Cambridge University Press:  01 May 2009

B. D. T. Lynas ,
C. C. Rundle  and
R. W. Sanderson
B. D. T. Lynas
Affiliation:
British Geological Survey, Keyworth, Nottingham NG12 5GG, U.K.
C. C. Rundle
Affiliation:
British Geological Survey, 64 Gray's Inn Road, London WC1X 8NG, U.K.
R. W. Sanderson
Affiliation:
British Geological Survey, Exhibition Road, London SW7, U.K.
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Abstract

Geological survey, electron microprobe analyses of clinopyroxenes and isotopic age determinations have revealed that the intrusive dolerites and basic–intermediate lavas of the Shelve Ordovician Inlier are part of a co-magmatic suite which show transitional affinities between tholeiites and alkali basalts. The ages of most of the intrusives are shown to be mid-Ordovician.

Type
Articles
Information
Geological Magazine , Volume 122 , Issue 6 , November 1985 , pp. 641 - 647
Copyright
Copyright © Cambridge University Press 1985

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