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Fold Structures in the Mylor Beds, near Porthleven, Cornwall

Published online by Cambridge University Press:  01 May 2009

Maurice Stone
Maurice Stone
Affiliation:
Department of Geology, University of Exeter, Exeter, Devon.
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Abstract

Early folds (F1) in the Mylor Beds are upright or overturned to the north-west and trend north-easterly. They are cut by a flat-lying cleavage (S2) which is related to small-scale recumbent folds (F2) superimposed on the steep limbs of the early folds. The sequence of development of folds can be found elsewhere in the Mylor-Gram-scatho Beds and also in the Lizard Head mica schists. It is shown that F2 folds and S2 cleavage resulted from vertical shortening, which is believed to have been caused by the superimposition of slide sheets. It is suggested that the previously accepted age order of the Mylor and Gramscatho Beds should be reversed.

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Articles
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Geological Magazine , Volume 103 , Issue 5 , October 1966 , pp. 440 - 460
Copyright
Copyright © Cambridge University Press 1966

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