Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting
Plate-scale deformation is expected to impart seismic anisotropic fabrics on the lithosphere. Determination of the fast shear wave orientation (ϕ) and the delay time between the fast and slow split shear waves (δt) via SKS splitting can help place spatial and temporal constraints on lithospheric def...
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ftleicesterunfig:oai:figshare.com:article/10175189 2023-05-15T17:35:02+02:00 Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting Amy Gilligan Ian D. Bastow Emma Watson Fiona A. Darbyshire Vadim Levin William Menke Victoria Lane David Hawthorn Alistair Boyce Mitchell V. Liddell Laura Petrescu 2016-06-09T00:00:00Z https://figshare.com/articles/journal_contribution/Lithospheric_deformation_in_the_Canadian_Appalachians_evidence_from_shear_wave_splitting/10175189 unknown 2381/37859 https://figshare.com/articles/journal_contribution/Lithospheric_deformation_in_the_Canadian_Appalachians_evidence_from_shear_wave_splitting/10175189 CC BY 4.0 CC-BY Uncategorized IR content Text Journal contribution 2016 ftleicesterunfig 2021-11-11T19:40:05Z Plate-scale deformation is expected to impart seismic anisotropic fabrics on the lithosphere. Determination of the fast shear wave orientation (ϕ) and the delay time between the fast and slow split shear waves (δt) via SKS splitting can help place spatial and temporal constraints on lithospheric deformation. The Canadian Appalachians experienced multiple episodes of deformation during the Phanerozoic: accretionary collisions during the Palaeozoic prior to the collision between Laurentia and Gondwana, and rifting related to the Mesozoic opening of the North Atlantic. However, the extent to which extensional events have overprinted older orogenic trends is uncertain. We address this issue through measurements of seismic anisotropy beneath the Canadian Appalachians, computing shear wave splitting parameters (ϕ, δt) for new and existing seismic stations in Nova Scotia and New Brunswick. Average δt values of 1.2 s, relatively short length scale (≥100 km) splitting parameter variations, and a lack of correlation with absolute plate motion direction and mantle flow models, demonstrate that fossil lithospheric anisotropic fabrics dominate our results. Most fast directions parallel Appalachian orogenic trends observed at the surface, while δt values point towards coherent deformation of the crust and mantle lithosphere. Mesozoic rifting had minimal impact on our study area, except locally within the Bay of Fundy and in southern Nova Scotia, where fast directions are subparallel to the opening direction of Mesozoic rifting; associated δt values of >1 s require an anisotropic layer that spans both the crust and mantle, meaning the formation of the Bay of Fundy was not merely a thin-skinned tectonic event. Other Non-Article Part of Journal/Newspaper North Atlantic University of Leicester: Figshare |
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University of Leicester: Figshare |
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Uncategorized IR content Amy Gilligan Ian D. Bastow Emma Watson Fiona A. Darbyshire Vadim Levin William Menke Victoria Lane David Hawthorn Alistair Boyce Mitchell V. Liddell Laura Petrescu Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting |
topic_facet |
Uncategorized IR content |
description |
Plate-scale deformation is expected to impart seismic anisotropic fabrics on the lithosphere. Determination of the fast shear wave orientation (ϕ) and the delay time between the fast and slow split shear waves (δt) via SKS splitting can help place spatial and temporal constraints on lithospheric deformation. The Canadian Appalachians experienced multiple episodes of deformation during the Phanerozoic: accretionary collisions during the Palaeozoic prior to the collision between Laurentia and Gondwana, and rifting related to the Mesozoic opening of the North Atlantic. However, the extent to which extensional events have overprinted older orogenic trends is uncertain. We address this issue through measurements of seismic anisotropy beneath the Canadian Appalachians, computing shear wave splitting parameters (ϕ, δt) for new and existing seismic stations in Nova Scotia and New Brunswick. Average δt values of 1.2 s, relatively short length scale (≥100 km) splitting parameter variations, and a lack of correlation with absolute plate motion direction and mantle flow models, demonstrate that fossil lithospheric anisotropic fabrics dominate our results. Most fast directions parallel Appalachian orogenic trends observed at the surface, while δt values point towards coherent deformation of the crust and mantle lithosphere. Mesozoic rifting had minimal impact on our study area, except locally within the Bay of Fundy and in southern Nova Scotia, where fast directions are subparallel to the opening direction of Mesozoic rifting; associated δt values of >1 s require an anisotropic layer that spans both the crust and mantle, meaning the formation of the Bay of Fundy was not merely a thin-skinned tectonic event. |
format |
Other Non-Article Part of Journal/Newspaper |
author |
Amy Gilligan Ian D. Bastow Emma Watson Fiona A. Darbyshire Vadim Levin William Menke Victoria Lane David Hawthorn Alistair Boyce Mitchell V. Liddell Laura Petrescu |
author_facet |
Amy Gilligan Ian D. Bastow Emma Watson Fiona A. Darbyshire Vadim Levin William Menke Victoria Lane David Hawthorn Alistair Boyce Mitchell V. Liddell Laura Petrescu |
author_sort |
Amy Gilligan |
title |
Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting |
title_short |
Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting |
title_full |
Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting |
title_fullStr |
Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting |
title_full_unstemmed |
Lithospheric deformation in the Canadian Appalachians: evidence from shear wave splitting |
title_sort |
lithospheric deformation in the canadian appalachians: evidence from shear wave splitting |
publishDate |
2016 |
url |
https://figshare.com/articles/journal_contribution/Lithospheric_deformation_in_the_Canadian_Appalachians_evidence_from_shear_wave_splitting/10175189 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
2381/37859 https://figshare.com/articles/journal_contribution/Lithospheric_deformation_in_the_Canadian_Appalachians_evidence_from_shear_wave_splitting/10175189 |
op_rights |
CC BY 4.0 |
op_rightsnorm |
CC-BY |
_version_ |
1766134057108766720 |