The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland

Parnell, J., Mark, D., Fallick, A., Boyce, A. and Thackrey, S. (2011) The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland. Journal of the Geological Society, 168, pp. 349-358. (doi:10.1144/0016-76492010-099)

Full text not currently available from Enlighten.

Abstract

The Mesoproterozoic Stoer Group of the ‘Torridonian' has been dated at 1177 ± 5 Ma (2σ), based on 40Ar/39Ar dating of authigenic K-feldspars precipitated in degassing structures within the Stac Fada Member, interpreted previously as an impact ejecta deposit. Fluid inclusion analysis of the K-feldspar shows that it precipitated from hot fluids, and so must immediately post-date emplacement of the ejecta blanket. The oxygen isotopic composition of K-feldspar is remarkably constant at 9.7 ± 0.2‰ (V-SMOW) and is consistent with derivation from evaporated lake water. The new age supports previous determinations of 1199 ± 70 Ma from Pb–Pb dating of limestone and 1180 Ma from palaeomagnetic data, but provides much higher precision.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Mark, Professor Darren and Boyce, Professor Adrian and Fallick, Professor Anthony
Authors: Parnell, J., Mark, D., Fallick, A., Boyce, A., and Thackrey, S.
Subjects:G Geography. Anthropology. Recreation > GE Environmental Sciences
College/School:College of Science and Engineering > Scottish Universities Environmental Research Centre
Journal Name:Journal of the Geological Society
Publisher:Geological Society of London
ISSN:0016-7649
ISSN (Online):2041-479X
Published Online:01 January 2010

University Staff: Request a correction | Enlighten Editors: Update this record