Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data
We investigate the propagation of seismic waves in anisotropic ice. Two effects are important: (i) sudden changes in crystal orientation fabric (COF) lead to englacial reflections; (ii) the anisotropic fabric induces an angle dependency on the seismic velocities and, thus, recorded traveltimes. Velo...
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ftawi:oai:epic.awi.de:36085 2024-09-15T17:40:44+00:00 Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data Diez, Anja Eisen, Olaf Hofstede, Coen Lambrecht, Astrid Mayer, Christoph Miller, Heinrich Steinhage, Daniel Binder, Tobias Weikusat, Ilka 2014-08-04 application/pdf https://epic.awi.de/id/eprint/36085/ https://epic.awi.de/id/eprint/36085/1/tcd-8-4397-2014.pdf http://www.the-cryosphere-discuss.net/8/4397/2014/ https://hdl.handle.net/10013/epic.44097 https://hdl.handle.net/10013/epic.44097.d001 unknown Copernicus Publications https://epic.awi.de/id/eprint/36085/1/tcd-8-4397-2014.pdf https://hdl.handle.net/10013/epic.44097.d001 Diez, A. , Eisen, O. orcid:0000-0002-6380-962X , Hofstede, C. orcid:0000-0002-6015-6918 , Lambrecht, A. , Mayer, C. , Miller, H. , Steinhage, D. orcid:0000-0003-4737-9751 , Binder, T. and Weikusat, I. orcid:0000-0002-3023-6036 (2014) Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data , The Cryosphere Discussion, 8 (4), pp. 4397-4430 . doi:10.5194/tcd-8-4397-2014 <https://doi.org/10.5194/tcd-8-4397-2014> , hdl:10013/epic.44097 EPIC3The Cryosphere Discussion, Copernicus Publications, 8(4), pp. 4397-4430 Article notRev 2014 ftawi https://doi.org/10.5194/tcd-8-4397-2014 2024-06-24T04:09:53Z We investigate the propagation of seismic waves in anisotropic ice. Two effects are important: (i) sudden changes in crystal orientation fabric (COF) lead to englacial reflections; (ii) the anisotropic fabric induces an angle dependency on the seismic velocities and, thus, recorded traveltimes. Velocities calculated from the polycrystal elasticity tensor derived for the anisotropic fabric from measured COF eigenvalues of the EDML ice core, Antarctica, show good agreement with the velocity trend determined from a vertical seismic profiling. The agreement of the absolute velocity values, however, depends on the choice of the monocrystal elasticity tensor used for the calculation of the polycrystal properties. With this validation of seismic velocities we make use of abrupt changes in COF as common reflection mechanism for seismic and radar data below the firn–ice transition to investigate their occurrence by comparison with ice-core data. Our results highlight the possibility to complement regional radar surveys with local, surface-based seismic deployment to separate isochrones in radar data from other mechanisms. This is important for the reconnaissance of future ice-core drill sites, where accurate isochrone (i.e. non-COF) layer integrity allows for synchronization with other cores, as well as studies of ice dynamics considering non-homogeneous viscosity from preferred crystal orientations. Article in Journal/Newspaper Antarc* Antarctica ice core The Cryosphere Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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ftawi |
language |
unknown |
description |
We investigate the propagation of seismic waves in anisotropic ice. Two effects are important: (i) sudden changes in crystal orientation fabric (COF) lead to englacial reflections; (ii) the anisotropic fabric induces an angle dependency on the seismic velocities and, thus, recorded traveltimes. Velocities calculated from the polycrystal elasticity tensor derived for the anisotropic fabric from measured COF eigenvalues of the EDML ice core, Antarctica, show good agreement with the velocity trend determined from a vertical seismic profiling. The agreement of the absolute velocity values, however, depends on the choice of the monocrystal elasticity tensor used for the calculation of the polycrystal properties. With this validation of seismic velocities we make use of abrupt changes in COF as common reflection mechanism for seismic and radar data below the firn–ice transition to investigate their occurrence by comparison with ice-core data. Our results highlight the possibility to complement regional radar surveys with local, surface-based seismic deployment to separate isochrones in radar data from other mechanisms. This is important for the reconnaissance of future ice-core drill sites, where accurate isochrone (i.e. non-COF) layer integrity allows for synchronization with other cores, as well as studies of ice dynamics considering non-homogeneous viscosity from preferred crystal orientations. |
format |
Article in Journal/Newspaper |
author |
Diez, Anja Eisen, Olaf Hofstede, Coen Lambrecht, Astrid Mayer, Christoph Miller, Heinrich Steinhage, Daniel Binder, Tobias Weikusat, Ilka |
spellingShingle |
Diez, Anja Eisen, Olaf Hofstede, Coen Lambrecht, Astrid Mayer, Christoph Miller, Heinrich Steinhage, Daniel Binder, Tobias Weikusat, Ilka Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data |
author_facet |
Diez, Anja Eisen, Olaf Hofstede, Coen Lambrecht, Astrid Mayer, Christoph Miller, Heinrich Steinhage, Daniel Binder, Tobias Weikusat, Ilka |
author_sort |
Diez, Anja |
title |
Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data |
title_short |
Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data |
title_full |
Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data |
title_fullStr |
Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data |
title_full_unstemmed |
Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data |
title_sort |
seismic wave propagation in anisotropic ice – part 2: effects of crystal anisotropy in geophysical data |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://epic.awi.de/id/eprint/36085/ https://epic.awi.de/id/eprint/36085/1/tcd-8-4397-2014.pdf http://www.the-cryosphere-discuss.net/8/4397/2014/ https://hdl.handle.net/10013/epic.44097 https://hdl.handle.net/10013/epic.44097.d001 |
genre |
Antarc* Antarctica ice core The Cryosphere |
genre_facet |
Antarc* Antarctica ice core The Cryosphere |
op_source |
EPIC3The Cryosphere Discussion, Copernicus Publications, 8(4), pp. 4397-4430 |
op_relation |
https://epic.awi.de/id/eprint/36085/1/tcd-8-4397-2014.pdf https://hdl.handle.net/10013/epic.44097.d001 Diez, A. , Eisen, O. orcid:0000-0002-6380-962X , Hofstede, C. orcid:0000-0002-6015-6918 , Lambrecht, A. , Mayer, C. , Miller, H. , Steinhage, D. orcid:0000-0003-4737-9751 , Binder, T. and Weikusat, I. orcid:0000-0002-3023-6036 (2014) Seismic wave propagation in anisotropic ice – Part 2: Effects of crystal anisotropy in geophysical data , The Cryosphere Discussion, 8 (4), pp. 4397-4430 . doi:10.5194/tcd-8-4397-2014 <https://doi.org/10.5194/tcd-8-4397-2014> , hdl:10013/epic.44097 |
op_doi |
https://doi.org/10.5194/tcd-8-4397-2014 |
_version_ |
1810486770918227968 |