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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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References

Brown, P. E., Miller, J. A. & Soper, N. J. 1964. Age of the principal intrusions of the Lake District. Proc. Yorks. geol. Soc. 34, 331–42.CrossRefGoogle Scholar
Eastwood, T., Hollingworth, S. E., Rose, W. C. C. & Trotter, F. M. 1968. Geology of the country around Cockermouth and Caldbeck. Mem. geol. Surv. U.K. x + 298 pp. H.M.S.O., London.Google Scholar
Green, J. F. N. 1918. The Skiddaw Granite. A structural study. Proc. Geol. Ass. 29, 126–36.CrossRefGoogle Scholar
Helm, D. G. 1970. Stratigraphy and structure in the Black Combe inlier, English Lake District. Proc. Yorks. geol. Soc. 38, 105–48.CrossRefGoogle Scholar
Helm, D. G. & Roberts, B. 1968. The Caledonian history of the north-eastern Irish Sea region (letter). Scott. J. Geol. 4, 375–6.CrossRefGoogle Scholar
Helm, D. G., Roberts, B. & Simpson, A. 1963. Polyphase folding in the Caledonides south of the Scottish Highlands. Nature, Lond. 200, 1060–2.CrossRefGoogle Scholar
Miller, J. A. 1962. The potassium–argon ages of the Skiddaw and Eskdale granites. Geophys. J. 6, 391–3.CrossRefGoogle Scholar
Mitchell, G. H. 1956. The geological history of the Lake District. Proc. Yorks. geol. Soc. 30, 407–63.CrossRefGoogle Scholar
Rastall, R. H. 1910. The Skiddaw Granite and its metamorphism. Q. Jl geol. Soc. Lond. 66, 116–40.CrossRefGoogle Scholar
Roberts, D. E. 1971. Structures of the Skiddaw Slates in the Caldew valley, Cumberland. Geol. J. 7, 225–38.CrossRefGoogle Scholar
Simpson, A. 1967. The stratigraphy and tectonics of the Skiddaw Slates and the relationship of the overlying Borrowdale Volcanic Series in part of the Lake District. Geol. J. 5, 391–418.CrossRefGoogle Scholar
Simpson, A. 1968a. The Caledonian history of the north-eastern Irish Sea region and its relation to surrounding areas. Scott. J. Geol. 4, 135–63.CrossRefGoogle Scholar
Simpson, A. 1968b. The Caledonian history of the north-eastern Irish Sea region (letter). Scott. J. Geol. 4, 380–5.CrossRefGoogle Scholar
Soper, N. J., 1970. Three critical localities on the junction of the Borrowdale Volcanic rocks with the Skiddaw Slates in the Lake District. Proc. Yorks. geol. Soc. 37, 461–93.CrossRefGoogle Scholar
Soper, N. J. & Brown, P. E. 1968. The Caledonian history of the north-eastern Irish Sea region (letter). Scott. J. Geol. 4, 378–9.Google Scholar
Spry, A. 1969. Metamorphic Textures. viii + 350 pp. Pergamon Press, Oxford.Google Scholar
Wadge, A. J. & Burgess, I. C. 1968. The Caledonian history of the north-eastern Irish Sea region (letter). Scott. J. Geol. 4, 377.Google Scholar