Reinterpretation of the RRISP-77 Iceland shear-wave profiles
Two shear-wave profiles, E and G, collected during the 1977 Reykjanes Ridge Iceland Seismic Experiment have played an important role in models of the Icelandic crust. They were originally interpreted as indicating very low shear-wave velocities and abnormally low shear-wave quality factors in the 10...
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fthighwire:oai:open-archive.highwire.org:gji:126/1/166 2023-05-15T16:46:52+02:00 Reinterpretation of the RRISP-77 Iceland shear-wave profiles Menke, William Brandsdóttir, Bryndís Einarsson, Páll Bjarnason, Ingi Th. 1996-07-01 00:00:00.0 text/html http://gji.oxfordjournals.org/cgi/content/short/126/1/166 https://doi.org/10.1111/j.1365-246X.1996.tb05275.x en eng Oxford University Press http://gji.oxfordjournals.org/cgi/content/short/126/1/166 http://dx.doi.org/10.1111/j.1365-246X.1996.tb05275.x Copyright (C) 1996, Oxford University Press Research Papers TEXT 1996 fthighwire https://doi.org/10.1111/j.1365-246X.1996.tb05275.x 2012-11-23T22:10:27Z Two shear-wave profiles, E and G, collected during the 1977 Reykjanes Ridge Iceland Seismic Experiment have played an important role in models of the Icelandic crust. They were originally interpreted as indicating very low shear-wave velocities and abnormally low shear-wave quality factors in the 10–15 km depth range. These attributes, which are indicative of near-solidus temperatures, were used to support the hypothesis that the crust of Iceland is relatively thin (10–15 km) and underlain by partially molten material. More recent seismic data, however, contradict this hypothesis and suggest that the crust is thicker (20–30 km) and cooler. A re-examination of the RRISP-77 data indicates that the low shear-wave velocities are artefacts arising from source static anomalies (in the case of profile G) and misidentification of a secondary shear phase, S m S , as S (in the case of profile E). Furthermore, the attenuation occurs at ranges when rays from the shots pass near the Askja (profile E) and Katla and Oraefajokull (profile G) volcanoes. It may therefore have a localized source, and not be diagnostic of Icelandic crust as a whole. This new interpretation of the RRISP-77 shear-wave data is consistent with models having a thick, cold crust. Text Iceland Katla HighWire Press (Stanford University) Reykjanes ENVELOPE(-22.250,-22.250,65.467,65.467) Katla ENVELOPE(-19.062,-19.062,63.631,63.631) Askja ENVELOPE(-16.802,-16.802,65.042,65.042) Geophysical Journal International 126 1 166 172 |
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HighWire Press (Stanford University) |
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fthighwire |
language |
English |
topic |
Research Papers |
spellingShingle |
Research Papers Menke, William Brandsdóttir, Bryndís Einarsson, Páll Bjarnason, Ingi Th. Reinterpretation of the RRISP-77 Iceland shear-wave profiles |
topic_facet |
Research Papers |
description |
Two shear-wave profiles, E and G, collected during the 1977 Reykjanes Ridge Iceland Seismic Experiment have played an important role in models of the Icelandic crust. They were originally interpreted as indicating very low shear-wave velocities and abnormally low shear-wave quality factors in the 10–15 km depth range. These attributes, which are indicative of near-solidus temperatures, were used to support the hypothesis that the crust of Iceland is relatively thin (10–15 km) and underlain by partially molten material. More recent seismic data, however, contradict this hypothesis and suggest that the crust is thicker (20–30 km) and cooler. A re-examination of the RRISP-77 data indicates that the low shear-wave velocities are artefacts arising from source static anomalies (in the case of profile G) and misidentification of a secondary shear phase, S m S , as S (in the case of profile E). Furthermore, the attenuation occurs at ranges when rays from the shots pass near the Askja (profile E) and Katla and Oraefajokull (profile G) volcanoes. It may therefore have a localized source, and not be diagnostic of Icelandic crust as a whole. This new interpretation of the RRISP-77 shear-wave data is consistent with models having a thick, cold crust. |
format |
Text |
author |
Menke, William Brandsdóttir, Bryndís Einarsson, Páll Bjarnason, Ingi Th. |
author_facet |
Menke, William Brandsdóttir, Bryndís Einarsson, Páll Bjarnason, Ingi Th. |
author_sort |
Menke, William |
title |
Reinterpretation of the RRISP-77 Iceland shear-wave profiles |
title_short |
Reinterpretation of the RRISP-77 Iceland shear-wave profiles |
title_full |
Reinterpretation of the RRISP-77 Iceland shear-wave profiles |
title_fullStr |
Reinterpretation of the RRISP-77 Iceland shear-wave profiles |
title_full_unstemmed |
Reinterpretation of the RRISP-77 Iceland shear-wave profiles |
title_sort |
reinterpretation of the rrisp-77 iceland shear-wave profiles |
publisher |
Oxford University Press |
publishDate |
1996 |
url |
http://gji.oxfordjournals.org/cgi/content/short/126/1/166 https://doi.org/10.1111/j.1365-246X.1996.tb05275.x |
long_lat |
ENVELOPE(-22.250,-22.250,65.467,65.467) ENVELOPE(-19.062,-19.062,63.631,63.631) ENVELOPE(-16.802,-16.802,65.042,65.042) |
geographic |
Reykjanes Katla Askja |
geographic_facet |
Reykjanes Katla Askja |
genre |
Iceland Katla |
genre_facet |
Iceland Katla |
op_relation |
http://gji.oxfordjournals.org/cgi/content/short/126/1/166 http://dx.doi.org/10.1111/j.1365-246X.1996.tb05275.x |
op_rights |
Copyright (C) 1996, Oxford University Press |
op_doi |
https://doi.org/10.1111/j.1365-246X.1996.tb05275.x |
container_title |
Geophysical Journal International |
container_volume |
126 |
container_issue |
1 |
container_start_page |
166 |
op_container_end_page |
172 |
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1766036956085485568 |