VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS
To investigate the effects of location of a seismograph station on the records obtained, P waves from seismograms of Alaskan earthquakes recorded at four Canadian Arctic stations, Coppermine, Mould Bay, Resolute, and Alert have been analyzed spectrally. Differences in spectral amplitude at very low...
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Canadian Science Publishing
1966
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Online Access: | http://dx.doi.org/10.1139/e66-042 http://www.nrcresearchpress.com/doi/pdf/10.1139/e66-042 |
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crcansciencepubl:10.1139/e66-042 2023-12-17T10:25:03+01:00 VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS Utsu, Tokuji 1966 http://dx.doi.org/10.1139/e66-042 http://www.nrcresearchpress.com/doi/pdf/10.1139/e66-042 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 3, issue 5, page 597-621 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1966 crcansciencepubl https://doi.org/10.1139/e66-042 2023-11-19T13:39:26Z To investigate the effects of location of a seismograph station on the records obtained, P waves from seismograms of Alaskan earthquakes recorded at four Canadian Arctic stations, Coppermine, Mould Bay, Resolute, and Alert have been analyzed spectrally. Differences in spectral amplitude at very low frequencies among the stations and between earthquakes can reasonably be explained by a consideration of earthquake magnitude, epicentral distance, and mechanism. Differences in the shape of the spectral curves between stations result mainly from local crustal structures beneath the station. Increased absorption of waves is observed beneath Resolute. Use of the vertical to radial-horizontal spectral amplitude ratios gives an approximate estimate of the thickness of the crust and surface layer beneath these stations, although some phenomena noted cannot be explained by the theory of signal reverberation in a horizontally layered system with perfect elasticity. This analysis suggests that the crust thins toward the Arctic Ocean: the best estimates of crustal thickness are about 45 km at Coppermine, about 33 km at Resolute, about 23 at Alert, and about 18 km at Mould Bay. The latter depth is the most uncertain. There is a low velocity surface layer with a thickness of several hundred meters at Mould Bay, Resolute, and Alert. Article in Journal/Newspaper Arctic Arctic Ocean Mould Bay Canadian Science Publishing (via Crossref) Arctic Arctic Ocean Mould Bay ENVELOPE(-119.436,-119.436,76.197,76.197) Canadian Journal of Earth Sciences 3 5 597 621 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Utsu, Tokuji VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS |
topic_facet |
General Earth and Planetary Sciences |
description |
To investigate the effects of location of a seismograph station on the records obtained, P waves from seismograms of Alaskan earthquakes recorded at four Canadian Arctic stations, Coppermine, Mould Bay, Resolute, and Alert have been analyzed spectrally. Differences in spectral amplitude at very low frequencies among the stations and between earthquakes can reasonably be explained by a consideration of earthquake magnitude, epicentral distance, and mechanism. Differences in the shape of the spectral curves between stations result mainly from local crustal structures beneath the station. Increased absorption of waves is observed beneath Resolute. Use of the vertical to radial-horizontal spectral amplitude ratios gives an approximate estimate of the thickness of the crust and surface layer beneath these stations, although some phenomena noted cannot be explained by the theory of signal reverberation in a horizontally layered system with perfect elasticity. This analysis suggests that the crust thins toward the Arctic Ocean: the best estimates of crustal thickness are about 45 km at Coppermine, about 33 km at Resolute, about 23 at Alert, and about 18 km at Mould Bay. The latter depth is the most uncertain. There is a low velocity surface layer with a thickness of several hundred meters at Mould Bay, Resolute, and Alert. |
format |
Article in Journal/Newspaper |
author |
Utsu, Tokuji |
author_facet |
Utsu, Tokuji |
author_sort |
Utsu, Tokuji |
title |
VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS |
title_short |
VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS |
title_full |
VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS |
title_fullStr |
VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS |
title_full_unstemmed |
VARIATIONS IN SPECTRA OF P WAVES RECORDED AT CANADIAN ARCTIC SEISMOGRAPH STATIONS |
title_sort |
variations in spectra of p waves recorded at canadian arctic seismograph stations |
publisher |
Canadian Science Publishing |
publishDate |
1966 |
url |
http://dx.doi.org/10.1139/e66-042 http://www.nrcresearchpress.com/doi/pdf/10.1139/e66-042 |
long_lat |
ENVELOPE(-119.436,-119.436,76.197,76.197) |
geographic |
Arctic Arctic Ocean Mould Bay |
geographic_facet |
Arctic Arctic Ocean Mould Bay |
genre |
Arctic Arctic Ocean Mould Bay |
genre_facet |
Arctic Arctic Ocean Mould Bay |
op_source |
Canadian Journal of Earth Sciences volume 3, issue 5, page 597-621 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e66-042 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
3 |
container_issue |
5 |
container_start_page |
597 |
op_container_end_page |
621 |
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1785572677462786048 |