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Solution Subsidence Outliers of Millstone Grit on the Carboniferous Limestone of the North Crop of the South Wales Coalfield

Published online by Cambridge University Press:  01 May 2009

Trevor M. Thomas
Affiliation:
“Ty Derw,” Ely Valley Road, Talbot Green, Llantrisant, Glam.

Abstract

A record has been made of the outliers of Basal Grit occurring on the Limestone of the North Crop of the South Wales Coalfield, some of which have not previously been located. The solution subsidence theory to account for their present anomalous levels when compared with the parent Grit outcrop to the south has been enlarged upon, and an attempt has been made to determine the mechanism of this subsidence which ranges in vertical extent up to a maximum of approximately 600 feet. The outliers are of economic importance since their predominant crumbly quartzose sandstones are a source of almost pure silica sand.

Type
Articles
Copyright
Copyright © Cambridge University Press 1954

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References

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