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The Caledonoid faults of northern Lleyn (North Wales)

Published online by Cambridge University Press:  01 May 2009

W. E. Tremlett
W. E. Tremlett
Affiliation:
Department of Geology, The University, Glasgow W.2.
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Summary

Evidence of substantial dextral strike-slip displacements along the Caledonoid fault-set of northern Lleyn is revealed by the distribution of Pre-Cambrian igneous and metamorphic rocks, Ordovician volcanic rocks and Caledonian ‘early granodioritic’ intrusions. These apparently occurred prior to some smaller sinistral strike-slip movements which left total net dextral displacements of 91/2 km. Both types of movement were completed before the Caledonoid faults were disrupted by NNW sinistral faulting and more intrusions of Lower Old Red Sandstone age were emplaced.

Type
Articles
Information
Geological Magazine , Volume 107 , Issue 3 , May 1970 , pp. 235 - 247
Copyright
Copyright © Cambridge University Press 1970

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References

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