Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon
Two new occurrences of eclogite associated with mylonitic rocks are documented. The first, near Ross River, is in a quartz-rich metasedimentary host that includes glaucophane schist. The host forms part of a belt of high-pressure rocks more than 50 km long and several kilometres wide between Ross Ri...
Published in: | Canadian Journal of Earth Sciences |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
1987
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1139/e87-136 http://www.nrcresearchpress.com/doi/pdf/10.1139/e87-136 |
id |
crcansciencepubl:10.1139/e87-136 |
---|---|
record_format |
openpolar |
spelling |
crcansciencepubl:10.1139/e87-136 2024-09-09T19:39:45+00:00 Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon Erdmer, Philippe 1987 http://dx.doi.org/10.1139/e87-136 http://www.nrcresearchpress.com/doi/pdf/10.1139/e87-136 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 24, issue 7, page 1439-1449 ISSN 0008-4077 1480-3313 journal-article 1987 crcansciencepubl https://doi.org/10.1139/e87-136 2024-08-01T04:10:03Z Two new occurrences of eclogite associated with mylonitic rocks are documented. The first, near Ross River, is in a quartz-rich metasedimentary host that includes glaucophane schist. The host forms part of a belt of high-pressure rocks more than 50 km long and several kilometres wide between Ross River and Faro. In the second occurrence, north of Watson Lake, eclogite is associated with mafic and ultramafic rocks occurring in a klippe more than 100 km 2 in area that rests on unmetamorphosed Triassic rocks of the North American miogeocline. Geothermobarometry shows that the eclogites were metamorphosed at 10–15 kb (1 kb = 100 MPa), between 470 and 750 °C. These peak conditions are comparable to those for other eclogites in the Yukon and adjacent Alaska. The age of metamorphism and mylonitization is Triassic or older.The high-pressure rocks occur at the leading edge of the most inboard accreted terrane, along its boundary with North American miogeoclinal strata, over a length of several hundred kilometres. Their extensive distribution makes these rocks regionally mappable units. This supports other evidence that both the Yukon–Tanana terrane and mylonite sheets obducted on North American foreland rocks are composed in part of trench and subduction-zone material. Article in Journal/Newspaper Faro Ross River Watson Lake Alaska Yukon Canadian Science Publishing Faro ENVELOPE(-133.353,-133.353,62.231,62.231) Yukon Canadian Journal of Earth Sciences 24 7 1439 1449 |
institution |
Open Polar |
collection |
Canadian Science Publishing |
op_collection_id |
crcansciencepubl |
language |
English |
description |
Two new occurrences of eclogite associated with mylonitic rocks are documented. The first, near Ross River, is in a quartz-rich metasedimentary host that includes glaucophane schist. The host forms part of a belt of high-pressure rocks more than 50 km long and several kilometres wide between Ross River and Faro. In the second occurrence, north of Watson Lake, eclogite is associated with mafic and ultramafic rocks occurring in a klippe more than 100 km 2 in area that rests on unmetamorphosed Triassic rocks of the North American miogeocline. Geothermobarometry shows that the eclogites were metamorphosed at 10–15 kb (1 kb = 100 MPa), between 470 and 750 °C. These peak conditions are comparable to those for other eclogites in the Yukon and adjacent Alaska. The age of metamorphism and mylonitization is Triassic or older.The high-pressure rocks occur at the leading edge of the most inboard accreted terrane, along its boundary with North American miogeoclinal strata, over a length of several hundred kilometres. Their extensive distribution makes these rocks regionally mappable units. This supports other evidence that both the Yukon–Tanana terrane and mylonite sheets obducted on North American foreland rocks are composed in part of trench and subduction-zone material. |
format |
Article in Journal/Newspaper |
author |
Erdmer, Philippe |
spellingShingle |
Erdmer, Philippe Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon |
author_facet |
Erdmer, Philippe |
author_sort |
Erdmer, Philippe |
title |
Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon |
title_short |
Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon |
title_full |
Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon |
title_fullStr |
Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon |
title_full_unstemmed |
Blueschist and eclogite in mylonitic allochthons, Ross River and Watson Lake areas, southeastern Yukon |
title_sort |
blueschist and eclogite in mylonitic allochthons, ross river and watson lake areas, southeastern yukon |
publisher |
Canadian Science Publishing |
publishDate |
1987 |
url |
http://dx.doi.org/10.1139/e87-136 http://www.nrcresearchpress.com/doi/pdf/10.1139/e87-136 |
long_lat |
ENVELOPE(-133.353,-133.353,62.231,62.231) |
geographic |
Faro Yukon |
geographic_facet |
Faro Yukon |
genre |
Faro Ross River Watson Lake Alaska Yukon |
genre_facet |
Faro Ross River Watson Lake Alaska Yukon |
op_source |
Canadian Journal of Earth Sciences volume 24, issue 7, page 1439-1449 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e87-136 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
24 |
container_issue |
7 |
container_start_page |
1439 |
op_container_end_page |
1449 |
_version_ |
1809908842961567744 |