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Mylonite-dominated footwall geometry in a shear zone, central Pyrenees

Published online by Cambridge University Press:  01 May 2009

C. W. Passchier
C. W. Passchier
Affiliation:
Department of Geology, University College of Swansea, Singleton Park, Swansea SA2 8PP, U.K.
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Abstract

A major ductile shear zone in the gneissic core of the Saint-Barthélemy Massif, central Pyrenees, is characterized by an asymmetric shear strain profile defined as mylonite-dominated footwall geometry. The shear zone is part of a low angle fault system in the massif which caused thinning of a sequence of lithologic units and isograds. The shear zone is interpreted as a low angle normal fault zone of probably Cretaceous age, predating Alpine crustal shortening in the central Pyrenees.

Type
Articles
Information
Geological Magazine , Volume 121 , Issue 5 , September 1984 , pp. 429 - 436
Copyright
Copyright © Cambridge University Press 1984

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