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Magnetic and tectonostratigraphic correlation at a terrane boundary: the Tappins Group of the Southern Uplands

Published online by Cambridge University Press:  01 May 2009

J. D. Floyd
Affiliation:
British Geological Survey, Murchison House, West Mains Road, Edinburgh EH9 3LA, UK
G. S. Kimbell
Affiliation:
British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG, UK

Abstract

Prominent aeromagnetic anomalies around Ballantrae in southwest Scotland have long been associated with extensive outcrops of basic/ultrabasic igneous rocks in the Midland Valley terrane. However, recent reprocessing of data from a 1978 detailed aeromagnetic survey has demonstrated excellent correlation between discrete aeromagnetic features and certain magnetic greywacke formations within the early Caradoc Tappins Group. This heterogeneous unit forms the oldest and most northwesterly tectonostratigraphic tract in the Southern Uplands terrane and is characterized by relatively high detrital magnetite(and serpentinite) content and elevated values for Cr and Ni. This suggests original close sedimentary links with an ophiolitic terrane not unlike the presently adjacent Ballantrae Complex (or its extensive along-strike correlatives), a consideration which has important implications for terrane reconstructions in this region.

Type
Articles
Copyright
Copyright © Cambridge University Press 1995

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