Journal article
Geologic Setting of Eclogite-facies Assemblages in the St. Cyr Klippe, Yukon-Tanana Terrane, Yukon, Canada
Geoscience Canada, Vol.42(3), pp.327-350
01/01/2015
DOI: 10.12789/geocanj.2015.42.073
Abstract
The St. Cyr area near Quiet Lake hosts well-preserved to variably retrogressed eclogite found as sub-metre to hundreds of metre-long lenses within quartzofeldspathic schist in southcentral Yukon, Canada. The St. Cyr klippe consists of structurally imbricated, polydeformed and polymetamorphosed units of continental arc crust and ultramafic-mafic rocks. Eclogite-bearing quartzofeldspathic schist forms thrust slices in a 30 km long by 6 km wide, northwest-striking outcrop belt. The schist unit comprises metasedimentary and felsic intrusive rocks that are intercalated on the metre to tens of metres scale. Ultramafic rocks, serpentinite and associated greenschist-facies metagabbro form imbricated tectonic slices within the eclogite- bearing quartzofeldspathic unit, which led to a previously held hypothesis that eclogite was exhumed within a tectonic melange. The presence of phengite and Permian zircon crystallized under eclogite-facies metamorphic conditions in the quartzofeldspathic host rocks indicate that the eclogite was metamorphosed in situ together with the schist as a coherent unit that was part of the continental arc crust of the Yukon-Tanana terrane, rather than a melange associated with the subduction of oceanic crust of the Slide Mountain terrane. Petrological, geochemical, geochronological and structural similarities link St. Cyr eclogite to other high-pressure localities within Yukon, indicating the high-pressure assemblages form a larger lithotectonic unit within the Yukon-Tanana terrane.
Details
- Title: Subtitle
- Geologic Setting of Eclogite-facies Assemblages in the St. Cyr Klippe, Yukon-Tanana Terrane, Yukon, Canada
- Creators
- M. B Petrie - University of IowaJ. A Gilotti - University of IowaW. C McClelland - University of IowaC van Staal - Geological Survey of CanadaS. J Isard - University of Iowa
- Resource Type
- Journal article
- Publication Details
- Geoscience Canada, Vol.42(3), pp.327-350
- Publisher
- GEOLOGICAL ASSOC CANADA
- DOI
- 10.12789/geocanj.2015.42.073
- ISSN
- 0315-0941
- eISSN
- 1911-4850
- Number of pages
- 24
- Grant note
- EAR-1118834 / National Science Foundation Geological Society of America Student Research Grant Professoriate Fellowship and Department of Earth and Environmental Sciences, University of Iowa Geological Survey of Canada Alliances for Graduate Education
- Language
- English
- Date published
- 01/01/2015
- Academic Unit
- Earth and Environmental Sciences
- Record Identifier
- 9984240903402771
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