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The Denbigh Grits; Wenlock Greywackes in Wales

Published online by Cambridge University Press:  01 May 2009

W. A. Cummins
W. A. Cummins
Affiliation:
Department of Geology, The University, Nottingham.
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Abstract

The petrography of the greywackes is described, with special emphasis on rock and mineral grains indicative of provenance. Sedimentary structures are discussed, and current directions based on flute cast measurements are recorded. The stratigraphy and palaeontology of the Denbigh Grits, and the facies of other parts of the Wenlock in the Welsh area are also considered. It is concluded that the greywackes were derived from an area of Pre-Cambrian rocks near south-west Wales and that they were transported along the axes of subsiding troughs by turbidity currents.

Type
Articles
Information
Geological Magazine , Volume 94 , Issue 6 , December 1957 , pp. 433 - 451
Copyright
Copyright © Cambridge University Press 1957

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