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The minor intrusions of Assynt, NW Scotland: early development of magmatism along the Caledonian Front

Published online by Cambridge University Press:  05 July 2018

K. M. Goodenough ,
B. N. Young  and
I. Parsons
K. M. Goodenough*
Affiliation:
British Geological Survey, West Mains Road, Edinburgh EH9 3LA, UK
B. N. Young
Affiliation:
Department of Geology and Mineralogy, University of Aberdeen, Marischal College, Broad Street, Aberdeen AB24 3UE, UK Baker Hughes Inteq, Barclayhill Place, Portlethen, Aberdeen AB12 4PF, UK
I. Parsons
Affiliation:
Grant Institute of Earth Science, University of Edinburgh, West Mains Road, Edinburgh EH9 3JW, UK
*
*E-mail: [email protected]
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Abstract

The Assynt Culmination of the Moine Thrust Belt, in the northwest Scottish Highlands, contains a variety of Caledonian alkaline and calc-alkaline intrusions that are mostly of Silurian age. These include a significant but little-studied suite of dykes and sills, the Northwest Highlands Minor Intrusion Suite. We describe the structural relationships of these minor intrusions and suggest a classification into seven swarms. The majority of the minor intrusions can be shown to pre-date movement in the Moine Thrust Belt, but some appear to have been intruded during the period of thrusting. A complex history of magmatism is thus recorded within this part of the Moine Thrust Belt. New geochemical data provide evidence of a subduction-related component in the mantle source of the minor intrusions.

Keywords

AssyntCaledonianminor intrusionMoine ThrustScotland
Type
Research Article
Information
Mineralogical Magazine , Volume 68 , Issue 4 , August 2004 , pp. 541 - 559
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2004

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