Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data
Models of the seismic velocity structure of the crust in the seismically active northern Canadian Cordillera remain poorly constrained, despite their importance in the accurate location and characterization of regional earthquakes. On 29 August 2014, a moderate earthquake with magnitude 5.0, which g...
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crcansciencepubl:10.1139/cjes-2016-0115 2024-04-28T08:32:51+00:00 Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data Ma, Shutian Audet, Pascal 2017 http://dx.doi.org/10.1139/cjes-2016-0115 http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjes-2016-0115 http://www.nrcresearchpress.com/doi/pdf/10.1139/cjes-2016-0115 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 54, issue 2, page 163-172 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 2017 crcansciencepubl https://doi.org/10.1139/cjes-2016-0115 2024-04-09T06:56:26Z Models of the seismic velocity structure of the crust in the seismically active northern Canadian Cordillera remain poorly constrained, despite their importance in the accurate location and characterization of regional earthquakes. On 29 August 2014, a moderate earthquake with magnitude 5.0, which generated high-quality Rayleigh wave data, occurred in the Northwest Territories, Canada, ∼100 km to the east of the Cordilleran Deformation Front. We carefully selected 23 seismic stations that recorded the Rayleigh waves and divided them into 13 groups according to the azimuth angle between the earthquake and the stations; these groups mostly sample the Cordillera. In each group, we measured Rayleigh wave group velocity dispersion, which we inverted for one-dimensional shear-wave velocity models of the crust. We thus obtained 13 models that consistently show low seismic velocities with respect to reference models, with a slow upper and lower crust surrounding a relatively fast mid crustal layer. The average of the 13 models is consistent with receiver function data in the central portion of the Cordillera. Finally, we compared earthquake locations determined by the Geological Survey of Canada using a simple homogenous crust over a mantle half space with those estimated using the new crustal velocity model, and show that estimates can differ by as much as 10 km. Article in Journal/Newspaper Northwest Territories Canadian Science Publishing Canadian Journal of Earth Sciences 54 2 163 172 |
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Canadian Science Publishing |
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English |
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General Earth and Planetary Sciences |
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General Earth and Planetary Sciences Ma, Shutian Audet, Pascal Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data |
topic_facet |
General Earth and Planetary Sciences |
description |
Models of the seismic velocity structure of the crust in the seismically active northern Canadian Cordillera remain poorly constrained, despite their importance in the accurate location and characterization of regional earthquakes. On 29 August 2014, a moderate earthquake with magnitude 5.0, which generated high-quality Rayleigh wave data, occurred in the Northwest Territories, Canada, ∼100 km to the east of the Cordilleran Deformation Front. We carefully selected 23 seismic stations that recorded the Rayleigh waves and divided them into 13 groups according to the azimuth angle between the earthquake and the stations; these groups mostly sample the Cordillera. In each group, we measured Rayleigh wave group velocity dispersion, which we inverted for one-dimensional shear-wave velocity models of the crust. We thus obtained 13 models that consistently show low seismic velocities with respect to reference models, with a slow upper and lower crust surrounding a relatively fast mid crustal layer. The average of the 13 models is consistent with receiver function data in the central portion of the Cordillera. Finally, we compared earthquake locations determined by the Geological Survey of Canada using a simple homogenous crust over a mantle half space with those estimated using the new crustal velocity model, and show that estimates can differ by as much as 10 km. |
format |
Article in Journal/Newspaper |
author |
Ma, Shutian Audet, Pascal |
author_facet |
Ma, Shutian Audet, Pascal |
author_sort |
Ma, Shutian |
title |
Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data |
title_short |
Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data |
title_full |
Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data |
title_fullStr |
Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data |
title_full_unstemmed |
Seismic velocity model of the crust in the northern Canadian Cordillera from Rayleigh wave dispersion data |
title_sort |
seismic velocity model of the crust in the northern canadian cordillera from rayleigh wave dispersion data |
publisher |
Canadian Science Publishing |
publishDate |
2017 |
url |
http://dx.doi.org/10.1139/cjes-2016-0115 http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjes-2016-0115 http://www.nrcresearchpress.com/doi/pdf/10.1139/cjes-2016-0115 |
genre |
Northwest Territories |
genre_facet |
Northwest Territories |
op_source |
Canadian Journal of Earth Sciences volume 54, issue 2, page 163-172 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/cjes-2016-0115 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
54 |
container_issue |
2 |
container_start_page |
163 |
op_container_end_page |
172 |
_version_ |
1797589900660310016 |