Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures
This paper presents the first continental-scale study of the crust and upper mantle shear velocity (V_s) structure of Canada and adjacent regions using ambient noise tomography. Continuous waveform data recorded between 2003 and 2009 with 788 broadband seismograph stations in Canada and adjacent reg...
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ftcaltechauth:oai:authors.library.caltech.edu:43351 2023-05-15T16:35:30+02:00 Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures Kao, Honn Behr, Yannik Currie, Claire A. Hyndman, Roy Townend, John Lin, Fan-Chi Ritzwoller, Michael H. Shan, Shao-Ju He, Jiangheng 2013-11 application/pdf text/plain image/jpeg https://authors.library.caltech.edu/43351/ https://authors.library.caltech.edu/43351/1/jgrb50420.pdf https://authors.library.caltech.edu/43351/7/Supplement1.txt https://authors.library.caltech.edu/43351/8/Supplement2.txt https://authors.library.caltech.edu/43351/9/Kao_etal_2013JB010535RR_suppl_README.txt https://authors.library.caltech.edu/43351/10/FigS1_CCF_HF.jpg https://authors.library.caltech.edu/43351/11/FigS2_CCF_LF.jpg https://authors.library.caltech.edu/43351/12/FigS3_rayDensity.jpg https://authors.library.caltech.edu/43351/13/FigS4_crx_error.jpg https://resolver.caltech.edu/CaltechAUTHORS:20140114-080813432 en eng American Geophysical Union https://authors.library.caltech.edu/43351/1/jgrb50420.pdf https://authors.library.caltech.edu/43351/7/Supplement1.txt https://authors.library.caltech.edu/43351/8/Supplement2.txt https://authors.library.caltech.edu/43351/9/Kao_etal_2013JB010535RR_suppl_README.txt https://authors.library.caltech.edu/43351/10/FigS1_CCF_HF.jpg https://authors.library.caltech.edu/43351/11/FigS2_CCF_LF.jpg https://authors.library.caltech.edu/43351/12/FigS3_rayDensity.jpg https://authors.library.caltech.edu/43351/13/FigS4_crx_error.jpg Kao, Honn and Behr, Yannik and Currie, Claire A. and Hyndman, Roy and Townend, John and Lin, Fan-Chi and Ritzwoller, Michael H. and Shan, Shao-Ju and He, Jiangheng (2013) Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures. Journal of Geophysical Research. Solid Earth, 118 (11). pp. 5865-5887. ISSN 2169-9313. doi:10.1002/2013JB010535. https://resolver.caltech.edu/CaltechAUTHORS:20140114-080813432 <https://resolver.caltech.edu/CaltechAUTHORS:20140114-080813432> other Article PeerReviewed 2013 ftcaltechauth https://doi.org/10.1002/2013JB010535 2021-11-11T18:56:29Z This paper presents the first continental-scale study of the crust and upper mantle shear velocity (V_s) structure of Canada and adjacent regions using ambient noise tomography. Continuous waveform data recorded between 2003 and 2009 with 788 broadband seismograph stations in Canada and adjacent regions were used in the analysis. The higher primary frequency band of the ambient noise provides better resolution of crustal structures than previous tomographic models based on earthquake waveforms. Prominent low velocity anomalies are observed at shallow depths (<20 km) beneath the Gulf of St. Lawrence in east Canada, the sedimentary basins of west Canada, and the Cordillera. In contrast, the Canadian Shield exhibits high crustal velocities. We characterize the crust-mantle transition in terms of not only its depth and velocity but also its sharpness, defined by its thickness and the amount of velocity increase. Considerable variations in the physical properties of the crust-mantle transition are observed across Canada. Positive correlations between the crustal thickness, Moho velocity, and the thickness of the transition are evident throughout most of the craton except near Hudson Bay where the uppermost mantle V_s is relatively low. Prominent vertical V_s gradients are observed in the midcrust beneath the Cordillera and beneath most of the Canadian Shield. The midcrust velocity contrast beneath the Cordillera may correspond to a detachment zone associated with high temperatures immediately beneath, whereas the large midcrust velocity gradient beneath the Canadian Shield probably represents an ancient rheological boundary between the upper and lower crust. Article in Journal/Newspaper Hudson Bay Caltech Authors (California Institute of Technology) Canada Hudson Hudson Bay Journal of Geophysical Research: Solid Earth 118 11 5865 5887 |
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Open Polar |
collection |
Caltech Authors (California Institute of Technology) |
op_collection_id |
ftcaltechauth |
language |
English |
description |
This paper presents the first continental-scale study of the crust and upper mantle shear velocity (V_s) structure of Canada and adjacent regions using ambient noise tomography. Continuous waveform data recorded between 2003 and 2009 with 788 broadband seismograph stations in Canada and adjacent regions were used in the analysis. The higher primary frequency band of the ambient noise provides better resolution of crustal structures than previous tomographic models based on earthquake waveforms. Prominent low velocity anomalies are observed at shallow depths (<20 km) beneath the Gulf of St. Lawrence in east Canada, the sedimentary basins of west Canada, and the Cordillera. In contrast, the Canadian Shield exhibits high crustal velocities. We characterize the crust-mantle transition in terms of not only its depth and velocity but also its sharpness, defined by its thickness and the amount of velocity increase. Considerable variations in the physical properties of the crust-mantle transition are observed across Canada. Positive correlations between the crustal thickness, Moho velocity, and the thickness of the transition are evident throughout most of the craton except near Hudson Bay where the uppermost mantle V_s is relatively low. Prominent vertical V_s gradients are observed in the midcrust beneath the Cordillera and beneath most of the Canadian Shield. The midcrust velocity contrast beneath the Cordillera may correspond to a detachment zone associated with high temperatures immediately beneath, whereas the large midcrust velocity gradient beneath the Canadian Shield probably represents an ancient rheological boundary between the upper and lower crust. |
format |
Article in Journal/Newspaper |
author |
Kao, Honn Behr, Yannik Currie, Claire A. Hyndman, Roy Townend, John Lin, Fan-Chi Ritzwoller, Michael H. Shan, Shao-Ju He, Jiangheng |
spellingShingle |
Kao, Honn Behr, Yannik Currie, Claire A. Hyndman, Roy Townend, John Lin, Fan-Chi Ritzwoller, Michael H. Shan, Shao-Ju He, Jiangheng Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures |
author_facet |
Kao, Honn Behr, Yannik Currie, Claire A. Hyndman, Roy Townend, John Lin, Fan-Chi Ritzwoller, Michael H. Shan, Shao-Ju He, Jiangheng |
author_sort |
Kao, Honn |
title |
Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures |
title_short |
Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures |
title_full |
Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures |
title_fullStr |
Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures |
title_full_unstemmed |
Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures |
title_sort |
ambient seismic noise tomography of canada and adjacent regions: part i. crustal structures |
publisher |
American Geophysical Union |
publishDate |
2013 |
url |
https://authors.library.caltech.edu/43351/ https://authors.library.caltech.edu/43351/1/jgrb50420.pdf https://authors.library.caltech.edu/43351/7/Supplement1.txt https://authors.library.caltech.edu/43351/8/Supplement2.txt https://authors.library.caltech.edu/43351/9/Kao_etal_2013JB010535RR_suppl_README.txt https://authors.library.caltech.edu/43351/10/FigS1_CCF_HF.jpg https://authors.library.caltech.edu/43351/11/FigS2_CCF_LF.jpg https://authors.library.caltech.edu/43351/12/FigS3_rayDensity.jpg https://authors.library.caltech.edu/43351/13/FigS4_crx_error.jpg https://resolver.caltech.edu/CaltechAUTHORS:20140114-080813432 |
geographic |
Canada Hudson Hudson Bay |
geographic_facet |
Canada Hudson Hudson Bay |
genre |
Hudson Bay |
genre_facet |
Hudson Bay |
op_relation |
https://authors.library.caltech.edu/43351/1/jgrb50420.pdf https://authors.library.caltech.edu/43351/7/Supplement1.txt https://authors.library.caltech.edu/43351/8/Supplement2.txt https://authors.library.caltech.edu/43351/9/Kao_etal_2013JB010535RR_suppl_README.txt https://authors.library.caltech.edu/43351/10/FigS1_CCF_HF.jpg https://authors.library.caltech.edu/43351/11/FigS2_CCF_LF.jpg https://authors.library.caltech.edu/43351/12/FigS3_rayDensity.jpg https://authors.library.caltech.edu/43351/13/FigS4_crx_error.jpg Kao, Honn and Behr, Yannik and Currie, Claire A. and Hyndman, Roy and Townend, John and Lin, Fan-Chi and Ritzwoller, Michael H. and Shan, Shao-Ju and He, Jiangheng (2013) Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures. Journal of Geophysical Research. Solid Earth, 118 (11). pp. 5865-5887. ISSN 2169-9313. doi:10.1002/2013JB010535. https://resolver.caltech.edu/CaltechAUTHORS:20140114-080813432 <https://resolver.caltech.edu/CaltechAUTHORS:20140114-080813432> |
op_rights |
other |
op_doi |
https://doi.org/10.1002/2013JB010535 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
118 |
container_issue |
11 |
container_start_page |
5865 |
op_container_end_page |
5887 |
_version_ |
1766025725483155456 |