dc.contributor.author | Guice, G | |
dc.contributor.author | McDonald, I | |
dc.contributor.author | Hughes, H | |
dc.contributor.author | MacDonald, J | |
dc.contributor.author | Faithfull, J | |
dc.date.accessioned | 2020-03-09T09:27:52Z | |
dc.date.issued | 2020-03-09 | |
dc.description.abstract | The geodynamic regime(s) that predominated during the Archaean remains controversial, with the
plethora of competing models largely informed by felsic lithologies. Ultramafic-mafic rocks
displaying distinctive geochemical signatures are formed in a range of Phanerozoic geotectonic
environments. These rocks have high melting points, making them potentially useful tools for
investigating Archaean geodynamic processes in highly metamorphosed regions. We present field
mapping, petrography, traditional bulk-rock geochemistry, and platinum-group element
geochemistry for 12 ultramafic-mafic bodies in the Lewisian Gneiss Complex (LGC), which is a highly
metamorphosed fragment of the North Atlantic Craton in northwest Scotland. Our data indicate that
most of these occurrences are layered intrusions emplaced into the tonalite-trondhjemitegranodiorite (TTG)-dominated crust prior to polyphase metamorphism, representing a significant reevaluation of the LGC’s magmatic evolution. Of the others, two remain ambiguous, but one (Loch an
Daimh Mor) has some geochemical affinity with abyssal/orogenic peridotites and may represent a
fragment of Archaean mantle, although further investigation is required. The ultramafic-mafic
bodies in the LGC thus represent more than one type of event/process. Compared with the TTG host
rocks, these lithologies may preserve evidence of protolith origin(s), with potential to illuminate
tectonic setting(s) and geodynamic regimes of the early Earth. | en_GB |
dc.identifier.citation | Article jgs2020-013 | en_GB |
dc.identifier.doi | 10.1144/jgs2020-013 | |
dc.identifier.uri | http://hdl.handle.net/10871/120188 | |
dc.language.iso | en | en_GB |
dc.publisher | Geological Society | en_GB |
dc.rights.embargoreason | Under embargo until 9 March 2021 in compliance with publisher policy | en_GB |
dc.rights | © 2020 The Author(s). Published by The Geological Society of London. All rights reserved | en_GB |
dc.subject | Archaean geodynamics | en_GB |
dc.subject | Archean | en_GB |
dc.subject | cratonisation | en_GB |
dc.subject | North Atlantic Craton | en_GB |
dc.subject | Lewisian | en_GB |
dc.subject | PGE | en_GB |
dc.subject | granulite | en_GB |
dc.subject | layered intrusion | en_GB |
dc.subject | mantle | en_GB |
dc.title | The origin(s) and geodynamic significance of Archaean ultramafic-mafic bodies in the mainland Lewisian Gneiss Complex, North Atlantic Craton | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2020-03-09T09:27:52Z | |
dc.identifier.issn | 0016-7649 | |
dc.description | This is the author accepted manuscript. The final version is available from the Geological Society via the DOI in this record | en_GB |
dc.identifier.journal | Journal of the Geological Society | en_GB |
dc.rights.uri | http://www.rioxx.net/licenses/all-rights-reserved | en_GB |
dcterms.dateAccepted | 2020-03-02 | |
rioxxterms.version | AM | en_GB |
rioxxterms.licenseref.startdate | 2020-03-02 | |
rioxxterms.type | Journal Article/Review | en_GB |
refterms.dateFCD | 2020-03-06T17:47:18Z | |
refterms.versionFCD | AM | |
refterms.panel | B | en_GB |