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Tectonic Structures in the Devonian Rocks near Plymouth, Devon

Published online by Cambridge University Press:  01 May 2009

W. K. Fyson
W. K. Fyson
Affiliation:
Geology Department, University of Ottawa, Ottawa, Canada.
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Abstract

Minor folds in slates and sandstones are upright in the south and northerly overturned towards the north, and plunge approximately E.N.E. and W.S.W. towards three major N.W.–S.E. dextral faults. The folds are monoclinal and angular; regardless of attitude, the short limbs lie on the northerly sides of anticlines. Both slaty and fracture cleavages tend to parallel axial planes and local directions of extension. Similarly, the vertical axial planes may closely parallel those of major folds.

Boudins and W.N.W.–E.S.E. dextral oblique faults indicate extension along fold hinges, N.W.–S.E. dextral cross faults a change to N.–S. compression. Folded basic dykes parallel to faults and joints suggest early initiation of the fractures.

Type
Articles
Information
Geological Magazine , Volume 99 , Issue 3 , June 1962 , pp. 208 - 226
Copyright
Copyright © Cambridge University Press 1962

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