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The internal tectonic fabric of minor intrusions and their potential as regional palaeostress indicators

Published online by Cambridge University Press:  01 May 2009

Graham J. Borradaile
Affiliation:
Department of Geology, Lakehead University, Thunder Bay, Ontario P7B 5E1, Canada

Abstract

A suite of late-tectonic minor intrusive rocks in the Inner Hebrides of Scotland show a well developed internal tectonic fabric. This fabric has a similar orientation in adjacent intrusions and it is usually not seen in the wall rock. It is suggested that the intrusions' tectonic fabric records the effects of palaeostress over the cooling period of the intrusions and thus provides palaeostress trajectories over a geologically short period of time over the area occupied by the swarm of intrusions.

Type
Articles
Copyright
Copyright © Cambridge University Press 1986

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