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The Lower Cambrian Wrekin Quartzite and the age of its unconformity on the Ercall Granophyre

Published online by Cambridge University Press:  01 May 2009

A. E. Wright
Affiliation:
School of Earth Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.
I. J. Fairchild
Affiliation:
School of Earth Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.
F. Moseley
Affiliation:
School of Earth Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.
C. Downie
Affiliation:
Department of Geology, University of Sheffield, Mappin Street, Sheffield, S1 3JD, U.K.

Abstract

Acritarchs of Lower Cambrian age have been recovered from a clay horizon within conglomerates 6 m above the unconformity described by Cope & Gibbons (1987). The Wrekin Quartzite (34 m thick) represents beach deposits grading upwards into shelf sandstones. The stratigraphie evidence and recent age determinations suggest that although the granophyre was intruded at 560 ± 1 Ma the Cambrian Unconformity is younger than 533 ± 13 Ma.

Type
Articles
Copyright
Copyright © Cambridge University Press 1993

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