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The Mathry Dyke, a quartz-dolerite intrusion of probable Carboniferous age in southwest Wales

Published online by Cambridge University Press:  01 May 2009

R. Cave ,
J. D. Cornwell  and
A. D. Evans
R. Cave
Affiliation:
British Geological Survey, Llanfarian, Aberystwyth, Dyfed, SY23 4BY, U.K.
J. D. Cornwell
Affiliation:
British Geological Survey, Keyworth, Nottingham, NG12 5GG, U.K.
A. D. Evans
Affiliation:
British Geological Survey, Keyworth, Nottingham, NG12 5GG, U.K.
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Abstract

A previously unrecorded quartz-dolerite dyke some 40 km long and up to 15 m wide intrudes Lower Palaeozoic rocks in southwest Wales between Mathry and Llanboidy. It is of discontinuous subcrop but has an overall WNW trend. This crosscuts the Caledonian strike of the country rocks but is parallel with the line of the Hercynian front to the south. The dyke is probably related to the suite of Dinantian basalts and dolerites near the Bristol Channel, to the east of the South Wales Coalfield.

Type
Articles
Information
Geological Magazine , Volume 126 , Issue 6 , November 1989 , pp. 715 - 721
Copyright
Copyright © Cambridge University Press 1989

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