Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America
Precambrian tectonic processes are debated: what was the nature and scale of orogenic events on the younger, hotter, and more ductile Earth? Northern Hudson Bay records the Paleoproterozoic collision between the Western Churchill and Superior plates—the ∼1.8 Ga Trans-Hudson Orogeny (THO)—and is an i...
Published in: | Geochemistry, Geophysics, Geosystems |
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Online Access: | http://hdl.handle.net/10044/1/33260 https://doi.org/10.1002/2016GC006419 |
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ftimperialcol:oai:spiral.imperial.ac.uk:10044/1/33260 2023-05-15T15:35:25+02:00 Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America Gilligan, A Bastow, ID Darbyshire, FA The Leverhulme Trust 2016-06-01 http://hdl.handle.net/10044/1/33260 https://doi.org/10.1002/2016GC006419 unknown American Geophysical Union (AGU) Geochemistry Geophysics Geosystems © 2016. American Geophysical Union.All Rights Reserved. 2433 2421 Geochemistry & Geophysics 04 Earth Sciences 02 Physical Sciences Journal Article 2016 ftimperialcol https://doi.org/10.1002/2016GC006419 2018-09-16T05:55:09Z Precambrian tectonic processes are debated: what was the nature and scale of orogenic events on the younger, hotter, and more ductile Earth? Northern Hudson Bay records the Paleoproterozoic collision between the Western Churchill and Superior plates—the ∼1.8 Ga Trans-Hudson Orogeny (THO)—and is an ideal locality to study Precambrian tectonic structure. Integrated field, geochronological, and thermobarometric studies suggest that the THO was comparable to the present-day Himalayan-Karakoram-Tibet Orogen (HKTO). However, detailed understanding of the deep crustal architecture of the THO, and how it compares to that of the evolving HKTO, is lacking. The joint inversion of receiver functions and surface wave data provides new Moho depth estimates and shear velocity models for the crust and uppermost mantle of the THO. Most of the Archean crust is relatively thin (∼39 km) and structurally simple, with a sharp Moho; upper-crustal wave speed variations are attributed to postformation events. However, the Quebec-Baffin segment of the THO has a deeper Moho (∼45 km) and a more complex crustal structure. Observations show some similarity to recent models, computed using the same methods, of the HKTO crust. Based on Moho character, present-day crustal thickness, and metamorphic grade, we support the view that southern Baffin Island experienced thickening during the THO of a similar magnitude and width to present-day Tibet. Fast seismic velocities at >10 km below southern Baffin Island may be the result of partial eclogitization of the lower crust during the THO, as is currently thought to be happening in Tibet. Article in Journal/Newspaper Baffin Island Baffin Hudson Bay Imperial College London: Spiral Baffin Island Hudson Hudson Bay Geochemistry, Geophysics, Geosystems 17 6 2421 2433 |
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Imperial College London: Spiral |
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Geochemistry & Geophysics 04 Earth Sciences 02 Physical Sciences |
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Geochemistry & Geophysics 04 Earth Sciences 02 Physical Sciences Gilligan, A Bastow, ID Darbyshire, FA Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America |
topic_facet |
Geochemistry & Geophysics 04 Earth Sciences 02 Physical Sciences |
description |
Precambrian tectonic processes are debated: what was the nature and scale of orogenic events on the younger, hotter, and more ductile Earth? Northern Hudson Bay records the Paleoproterozoic collision between the Western Churchill and Superior plates—the ∼1.8 Ga Trans-Hudson Orogeny (THO)—and is an ideal locality to study Precambrian tectonic structure. Integrated field, geochronological, and thermobarometric studies suggest that the THO was comparable to the present-day Himalayan-Karakoram-Tibet Orogen (HKTO). However, detailed understanding of the deep crustal architecture of the THO, and how it compares to that of the evolving HKTO, is lacking. The joint inversion of receiver functions and surface wave data provides new Moho depth estimates and shear velocity models for the crust and uppermost mantle of the THO. Most of the Archean crust is relatively thin (∼39 km) and structurally simple, with a sharp Moho; upper-crustal wave speed variations are attributed to postformation events. However, the Quebec-Baffin segment of the THO has a deeper Moho (∼45 km) and a more complex crustal structure. Observations show some similarity to recent models, computed using the same methods, of the HKTO crust. Based on Moho character, present-day crustal thickness, and metamorphic grade, we support the view that southern Baffin Island experienced thickening during the THO of a similar magnitude and width to present-day Tibet. Fast seismic velocities at >10 km below southern Baffin Island may be the result of partial eclogitization of the lower crust during the THO, as is currently thought to be happening in Tibet. |
author2 |
The Leverhulme Trust |
format |
Article in Journal/Newspaper |
author |
Gilligan, A Bastow, ID Darbyshire, FA |
author_facet |
Gilligan, A Bastow, ID Darbyshire, FA |
author_sort |
Gilligan, A |
title |
Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America |
title_short |
Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America |
title_full |
Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America |
title_fullStr |
Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America |
title_full_unstemmed |
Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America |
title_sort |
seismological structure of the 1.8 ga trans-hudson orogen of north america |
publisher |
American Geophysical Union (AGU) |
publishDate |
2016 |
url |
http://hdl.handle.net/10044/1/33260 https://doi.org/10.1002/2016GC006419 |
geographic |
Baffin Island Hudson Hudson Bay |
geographic_facet |
Baffin Island Hudson Hudson Bay |
genre |
Baffin Island Baffin Hudson Bay |
genre_facet |
Baffin Island Baffin Hudson Bay |
op_source |
2433 2421 |
op_relation |
Geochemistry Geophysics Geosystems |
op_rights |
© 2016. American Geophysical Union.All Rights Reserved. |
op_doi |
https://doi.org/10.1002/2016GC006419 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
17 |
container_issue |
6 |
container_start_page |
2421 |
op_container_end_page |
2433 |
_version_ |
1766365746631278592 |