Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data
Teleseismic P waves passing through low-wave-speed bodies in the mantle are refracted, causing anomalies in their propagation directions that can be measured by seismometer arrays. Waves from earthquakes in the eastern Pacific and western North America arriving at the NORSAR array in Norway and at s...
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fthighwire:oai:open-archive.highwire.org:gji:143/1/119 2023-05-15T16:29:23+02:00 Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data Pritchard, M. J. Foulger, G. R. Julian, B. R. Fyen, J. 2000-10-01 00:00:00.0 text/html http://gji.oxfordjournals.org/cgi/content/short/143/1/119 https://doi.org/10.1046/j.1365-246x.2000.00221.x en eng Oxford University Press http://gji.oxfordjournals.org/cgi/content/short/143/1/119 http://dx.doi.org/10.1046/j.1365-246x.2000.00221.x Copyright (C) 2000, Oxford University Press Articles TEXT 2000 fthighwire https://doi.org/10.1046/j.1365-246x.2000.00221.x 2013-05-27T17:21:55Z Teleseismic P waves passing through low-wave-speed bodies in the mantle are refracted, causing anomalies in their propagation directions that can be measured by seismometer arrays. Waves from earthquakes in the eastern Pacific and western North America arriving at the NORSAR array in Norway and at seismic stations in Scotland pass beneath the Iceland region at depths of ∼ 1000–2000 km. Waves arriving at NORSAR have anomalous arrival azimuths consistent with a low-wave-speed body at a depth of ∼ 1500 km beneath the Iceland–Faeroe ridge with a maximum diameter of ∼250 km and a maximum wave-speed contrast of ∼ 1.5 per cent. This agrees well with whole-mantle tomography results, which image a low-wave-speed body at this location with a diameter of ∼ 500 km and a wave-speed anomaly of ∼ 0.5 per cent, bearing in mind that whole-mantle tomography, because of its limited resolution, broadens and weakens small anomalies. The observations cannot resolve the location of the body, and the anomaly could be caused in whole or in part by larger bodies farther away, for example by a body imaged beneath Greenland by whole-mantle tomography. Text Greenland Iceland HighWire Press (Stanford University) Greenland Pacific Norway Geophysical Journal International 143 1 119 128 |
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HighWire Press (Stanford University) |
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English |
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Articles |
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Articles Pritchard, M. J. Foulger, G. R. Julian, B. R. Fyen, J. Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data |
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Articles |
description |
Teleseismic P waves passing through low-wave-speed bodies in the mantle are refracted, causing anomalies in their propagation directions that can be measured by seismometer arrays. Waves from earthquakes in the eastern Pacific and western North America arriving at the NORSAR array in Norway and at seismic stations in Scotland pass beneath the Iceland region at depths of ∼ 1000–2000 km. Waves arriving at NORSAR have anomalous arrival azimuths consistent with a low-wave-speed body at a depth of ∼ 1500 km beneath the Iceland–Faeroe ridge with a maximum diameter of ∼250 km and a maximum wave-speed contrast of ∼ 1.5 per cent. This agrees well with whole-mantle tomography results, which image a low-wave-speed body at this location with a diameter of ∼ 500 km and a wave-speed anomaly of ∼ 0.5 per cent, bearing in mind that whole-mantle tomography, because of its limited resolution, broadens and weakens small anomalies. The observations cannot resolve the location of the body, and the anomaly could be caused in whole or in part by larger bodies farther away, for example by a body imaged beneath Greenland by whole-mantle tomography. |
format |
Text |
author |
Pritchard, M. J. Foulger, G. R. Julian, B. R. Fyen, J. |
author_facet |
Pritchard, M. J. Foulger, G. R. Julian, B. R. Fyen, J. |
author_sort |
Pritchard, M. J. |
title |
Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data |
title_short |
Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data |
title_full |
Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data |
title_fullStr |
Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data |
title_full_unstemmed |
Constraints on a plume in the mid-mantle beneath the Iceland region from seismic array data |
title_sort |
constraints on a plume in the mid-mantle beneath the iceland region from seismic array data |
publisher |
Oxford University Press |
publishDate |
2000 |
url |
http://gji.oxfordjournals.org/cgi/content/short/143/1/119 https://doi.org/10.1046/j.1365-246x.2000.00221.x |
geographic |
Greenland Pacific Norway |
geographic_facet |
Greenland Pacific Norway |
genre |
Greenland Iceland |
genre_facet |
Greenland Iceland |
op_relation |
http://gji.oxfordjournals.org/cgi/content/short/143/1/119 http://dx.doi.org/10.1046/j.1365-246x.2000.00221.x |
op_rights |
Copyright (C) 2000, Oxford University Press |
op_doi |
https://doi.org/10.1046/j.1365-246x.2000.00221.x |
container_title |
Geophysical Journal International |
container_volume |
143 |
container_issue |
1 |
container_start_page |
119 |
op_container_end_page |
128 |
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1766019080503951360 |