Influence of ice crystal anisotropy on seismic velocity analysis
In 2010 a reflection seismic survey was carried out on the Alpine glacier Colle Gnifetti. The processed and depth-converted data could be compared to a nearby ice core, drilled almost to the bed. Comparisons showed that the depth of the P-wave bed reflection was too shallow, while the depth of the S...
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Online Access: | https://hdl.handle.net/10278/5014707 https://doi.org/10.3189/2014AoG67A002 |
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ftuniveneziairis:oai:iris.unive.it:10278/5014707 2024-04-21T08:04:45+00:00 Influence of ice crystal anisotropy on seismic velocity analysis Diez A. Eisen O. Weikusat I. Eichler J. Hofstede C. Bohleber P. Bohlen T. Polom U. Diez, A. Eisen, O. Weikusat, I. Eichler, J. Hofstede, C. Bohleber, P. Bohlen, T. Polom, U. 2014 https://hdl.handle.net/10278/5014707 https://doi.org/10.3189/2014AoG67A002 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000339363400013 volume:55 issue:67 firstpage:97 lastpage:106 numberofpages:10 journal:ANNALS OF GLACIOLOGY https://hdl.handle.net/10278/5014707 doi:10.3189/2014AoG67A002 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84907320462 Anisotropic ice Glacier geophysic Ground-penetrating radar Ice crystal studie Seismics Settore GEO/08 - Geochimica e Vulcanologia Settore GEO/10 - Geofisica della Terra Solida Settore GEO/05 - Geologia Applicata info:eu-repo/semantics/article 2014 ftuniveneziairis https://doi.org/10.3189/2014AoG67A002 2024-03-28T01:24:22Z In 2010 a reflection seismic survey was carried out on the Alpine glacier Colle Gnifetti. The processed and depth-converted data could be compared to a nearby ice core, drilled almost to the bed. Comparisons showed that the depth of the P-wave bed reflection was too shallow, while the depth of the SH-wave bed reflection fitted the ice-core length well. We are now able to explain the major part of these differences using the existing crystal orientations of the ice at Colle Gnifetti. We calculate anisotropic velocities for P- and SH-waves that are usually picked for stacking and compare them with zero-offset velocities needed for the depth conversion. Here we take the firn pack at Colle Gnifetti into account for P- and S-wave analysis. To incorporate the S-wave analysis we first derive a new equation for the relationship between density and S-wave velocity from diving waves. We show that anisotropic fabrics observed at Colle Gnifetti introduce a difference of only 1% between stacking and depthconversion velocities for the SH-wave, but 7% for the P-wave. We suggest that this difference in stacking and depth-conversion velocity for the P-wave can be used to derive information about the existing anisotropy by combining our seismic data with, for example, radar data. Article in Journal/Newspaper ice core Università Ca’ Foscari Venezia: ARCA (Archivio Istituzionale della Ricerca) Annals of Glaciology 55 67 97 106 |
institution |
Open Polar |
collection |
Università Ca’ Foscari Venezia: ARCA (Archivio Istituzionale della Ricerca) |
op_collection_id |
ftuniveneziairis |
language |
English |
topic |
Anisotropic ice Glacier geophysic Ground-penetrating radar Ice crystal studie Seismics Settore GEO/08 - Geochimica e Vulcanologia Settore GEO/10 - Geofisica della Terra Solida Settore GEO/05 - Geologia Applicata |
spellingShingle |
Anisotropic ice Glacier geophysic Ground-penetrating radar Ice crystal studie Seismics Settore GEO/08 - Geochimica e Vulcanologia Settore GEO/10 - Geofisica della Terra Solida Settore GEO/05 - Geologia Applicata Diez A. Eisen O. Weikusat I. Eichler J. Hofstede C. Bohleber P. Bohlen T. Polom U. Influence of ice crystal anisotropy on seismic velocity analysis |
topic_facet |
Anisotropic ice Glacier geophysic Ground-penetrating radar Ice crystal studie Seismics Settore GEO/08 - Geochimica e Vulcanologia Settore GEO/10 - Geofisica della Terra Solida Settore GEO/05 - Geologia Applicata |
description |
In 2010 a reflection seismic survey was carried out on the Alpine glacier Colle Gnifetti. The processed and depth-converted data could be compared to a nearby ice core, drilled almost to the bed. Comparisons showed that the depth of the P-wave bed reflection was too shallow, while the depth of the SH-wave bed reflection fitted the ice-core length well. We are now able to explain the major part of these differences using the existing crystal orientations of the ice at Colle Gnifetti. We calculate anisotropic velocities for P- and SH-waves that are usually picked for stacking and compare them with zero-offset velocities needed for the depth conversion. Here we take the firn pack at Colle Gnifetti into account for P- and S-wave analysis. To incorporate the S-wave analysis we first derive a new equation for the relationship between density and S-wave velocity from diving waves. We show that anisotropic fabrics observed at Colle Gnifetti introduce a difference of only 1% between stacking and depthconversion velocities for the SH-wave, but 7% for the P-wave. We suggest that this difference in stacking and depth-conversion velocity for the P-wave can be used to derive information about the existing anisotropy by combining our seismic data with, for example, radar data. |
author2 |
Diez, A. Eisen, O. Weikusat, I. Eichler, J. Hofstede, C. Bohleber, P. Bohlen, T. Polom, U. |
format |
Article in Journal/Newspaper |
author |
Diez A. Eisen O. Weikusat I. Eichler J. Hofstede C. Bohleber P. Bohlen T. Polom U. |
author_facet |
Diez A. Eisen O. Weikusat I. Eichler J. Hofstede C. Bohleber P. Bohlen T. Polom U. |
author_sort |
Diez A. |
title |
Influence of ice crystal anisotropy on seismic velocity analysis |
title_short |
Influence of ice crystal anisotropy on seismic velocity analysis |
title_full |
Influence of ice crystal anisotropy on seismic velocity analysis |
title_fullStr |
Influence of ice crystal anisotropy on seismic velocity analysis |
title_full_unstemmed |
Influence of ice crystal anisotropy on seismic velocity analysis |
title_sort |
influence of ice crystal anisotropy on seismic velocity analysis |
publishDate |
2014 |
url |
https://hdl.handle.net/10278/5014707 https://doi.org/10.3189/2014AoG67A002 |
genre |
ice core |
genre_facet |
ice core |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000339363400013 volume:55 issue:67 firstpage:97 lastpage:106 numberofpages:10 journal:ANNALS OF GLACIOLOGY https://hdl.handle.net/10278/5014707 doi:10.3189/2014AoG67A002 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84907320462 |
op_doi |
https://doi.org/10.3189/2014AoG67A002 |
container_title |
Annals of Glaciology |
container_volume |
55 |
container_issue |
67 |
container_start_page |
97 |
op_container_end_page |
106 |
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1796944306682986496 |