Eclogite from central Yukon: a record of subduction at the western margin of ancient North America
Eclogite occurring in central Yukon, at Faro and near Last Peak, as lenses interleaved with muscovite–quartz blastomylonite has the chemical and field characteristics of group C rocks. From sigmoidal inclusion trails in garnet, from geothermometry and geobarometry, and from mineral parageneses, the...
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1983
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Online Access: | http://dx.doi.org/10.1139/e83-126 http://www.nrcresearchpress.com/doi/pdf/10.1139/e83-126 |
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crcansciencepubl:10.1139/e83-126 2023-12-17T10:29:57+01:00 Eclogite from central Yukon: a record of subduction at the western margin of ancient North America Erdmer, Philippe Helmstaedt, Herwart 1983 http://dx.doi.org/10.1139/e83-126 http://www.nrcresearchpress.com/doi/pdf/10.1139/e83-126 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 20, issue 9, page 1389-1408 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1983 crcansciencepubl https://doi.org/10.1139/e83-126 2023-11-19T13:39:08Z Eclogite occurring in central Yukon, at Faro and near Last Peak, as lenses interleaved with muscovite–quartz blastomylonite has the chemical and field characteristics of group C rocks. From sigmoidal inclusion trails in garnet, from geothermometry and geobarometry, and from mineral parageneses, the eclogite is inferred to have a crustal protolith and to have followed a hysteretic, subduction-cycle P–T trajectory. Transformation of basic igneous rock into schist was followed by eclogite metamorphism during which pressure was at least 1000 MPa and temperature was between 600 and 700 °C. Uplifting involved passage through the stability field of glaucophane; the eclogite and its host rocks were then subjected to greenschist fades metamorphism and deformation, with temperature at approximately 400 °C. The rocks were emplaced as thrust sheets against or onto the western North American cratonal margin. The tectonic boundary ranges from nearly vertical, where it is outlined by a zone of steeply dipping mélange, to nearly horizontal beneath klippen of cataclastic rocks that lie on North American miogeoclinal strata. Together with occurrences of eclogite on strike, in Yukon, near Fairbanks (Alaska), and near Pinchi Lake (British Columbia), eclogite at Faro and near Last Peak implies that the Yukon Cataclastic Complex is a deeply eroded collision mélange that borders over 1000 km of the ancient continental margin. Article in Journal/Newspaper Faro Alaska Yukon Canadian Science Publishing (via Crossref) Yukon Fairbanks Last Peak ENVELOPE(-134.221,-134.221,61.599,61.599) Faro ENVELOPE(-133.353,-133.353,62.231,62.231) Canadian Journal of Earth Sciences 20 9 1389 1408 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Erdmer, Philippe Helmstaedt, Herwart Eclogite from central Yukon: a record of subduction at the western margin of ancient North America |
topic_facet |
General Earth and Planetary Sciences |
description |
Eclogite occurring in central Yukon, at Faro and near Last Peak, as lenses interleaved with muscovite–quartz blastomylonite has the chemical and field characteristics of group C rocks. From sigmoidal inclusion trails in garnet, from geothermometry and geobarometry, and from mineral parageneses, the eclogite is inferred to have a crustal protolith and to have followed a hysteretic, subduction-cycle P–T trajectory. Transformation of basic igneous rock into schist was followed by eclogite metamorphism during which pressure was at least 1000 MPa and temperature was between 600 and 700 °C. Uplifting involved passage through the stability field of glaucophane; the eclogite and its host rocks were then subjected to greenschist fades metamorphism and deformation, with temperature at approximately 400 °C. The rocks were emplaced as thrust sheets against or onto the western North American cratonal margin. The tectonic boundary ranges from nearly vertical, where it is outlined by a zone of steeply dipping mélange, to nearly horizontal beneath klippen of cataclastic rocks that lie on North American miogeoclinal strata. Together with occurrences of eclogite on strike, in Yukon, near Fairbanks (Alaska), and near Pinchi Lake (British Columbia), eclogite at Faro and near Last Peak implies that the Yukon Cataclastic Complex is a deeply eroded collision mélange that borders over 1000 km of the ancient continental margin. |
format |
Article in Journal/Newspaper |
author |
Erdmer, Philippe Helmstaedt, Herwart |
author_facet |
Erdmer, Philippe Helmstaedt, Herwart |
author_sort |
Erdmer, Philippe |
title |
Eclogite from central Yukon: a record of subduction at the western margin of ancient North America |
title_short |
Eclogite from central Yukon: a record of subduction at the western margin of ancient North America |
title_full |
Eclogite from central Yukon: a record of subduction at the western margin of ancient North America |
title_fullStr |
Eclogite from central Yukon: a record of subduction at the western margin of ancient North America |
title_full_unstemmed |
Eclogite from central Yukon: a record of subduction at the western margin of ancient North America |
title_sort |
eclogite from central yukon: a record of subduction at the western margin of ancient north america |
publisher |
Canadian Science Publishing |
publishDate |
1983 |
url |
http://dx.doi.org/10.1139/e83-126 http://www.nrcresearchpress.com/doi/pdf/10.1139/e83-126 |
long_lat |
ENVELOPE(-134.221,-134.221,61.599,61.599) ENVELOPE(-133.353,-133.353,62.231,62.231) |
geographic |
Yukon Fairbanks Last Peak Faro |
geographic_facet |
Yukon Fairbanks Last Peak Faro |
genre |
Faro Alaska Yukon |
genre_facet |
Faro Alaska Yukon |
op_source |
Canadian Journal of Earth Sciences volume 20, issue 9, page 1389-1408 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e83-126 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
20 |
container_issue |
9 |
container_start_page |
1389 |
op_container_end_page |
1408 |
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1785582850156789760 |