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Age of cleavage in the Skiddaw Slates in relation to the Skiddaw aureole

Published online by Cambridge University Press:  01 May 2009

N. J. Soper  and
D. E. Roberts
N. J. Soper
Affiliation:
Department of Geology, University of Sheffield, Sheffield S1 3JD
D. E. Roberts
Affiliation:
Department of Geology, University College of Wales, Aberystwyth
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Summary

A recent hypothesis concerning the age of orogenic deformation of the Skiddaw Slates in the English Lake District has proposed that the main slaty cleavage (S1) and superimposed subhorizontal crenulation-cleavage (S2) are of intra-Ordovician age. A study of the fabric of the aureole of the (end-Silurian) Skiddaw granite shows that the granite was emplaced towards the end of the D1 deformation phase, but before the formation of S2. These structures are therefore of broadly end-Silurian age, and evidence of an intra-Ordovician orogeny in this area is lacking.

Type
Articles
Information
Geological Magazine , Volume 108 , Issue 4 , July 1971 , pp. 293 - 302
Copyright
Copyright © Cambridge University Press 1971

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