The role of electrical conductivity in radar wave reflection from glacier beds
We have examined a general expression giving the specular reflection coefficient for a radar wave approaching a reflecting interface with normal incidence. The reflecting interface separates two homogeneous isotropic media, the properties of which are fully described by three scalar quantities: diel...
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ftcopernicus:oai:publications.copernicus.org:tc82882 2023-05-15T13:31:39+02:00 The role of electrical conductivity in radar wave reflection from glacier beds Tulaczyk, Slawek M. Foley, Neil T. 2020-12-08 application/pdf https://doi.org/10.5194/tc-14-4495-2020 https://tc.copernicus.org/articles/14/4495/2020/ eng eng doi:10.5194/tc-14-4495-2020 https://tc.copernicus.org/articles/14/4495/2020/ eISSN: 1994-0424 Text 2020 ftcopernicus https://doi.org/10.5194/tc-14-4495-2020 2020-12-14T17:22:14Z We have examined a general expression giving the specular reflection coefficient for a radar wave approaching a reflecting interface with normal incidence. The reflecting interface separates two homogeneous isotropic media, the properties of which are fully described by three scalar quantities: dielectric permittivity, magnetic permeability, and electrical conductivity. The derived relationship indicates that electrical conductivity should not be neglected a priori in glaciological investigations of subglacial materials and in ground-penetrating radar (GPR) studies of saturated sediments and bedrock, even at the high end of typical linear radar frequencies used in such investigations (e.g., 100–400 MHz). Our own experience in resistivity surveying in Antarctica, combined with a literature review, suggests that a wide range of geologic materials can have electrical conductivity that is high enough to significantly impact the value of radar reflectivity. Furthermore, we have given two examples of prior studies in which inclusion of electrical conductivity in calculation of the radar bed reflectivity may provide an explanation for results that may be considered surprising if the impact of electrical conductivity on radar reflection is neglected. The commonly made assumption that only dielectric permittivity of the two media needs to be considered in interpretation of radar reflectivity can lead to erroneous conclusions. Text Antarc* Antarctica Copernicus Publications: E-Journals The Cryosphere 14 12 4495 4506 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
description |
We have examined a general expression giving the specular reflection coefficient for a radar wave approaching a reflecting interface with normal incidence. The reflecting interface separates two homogeneous isotropic media, the properties of which are fully described by three scalar quantities: dielectric permittivity, magnetic permeability, and electrical conductivity. The derived relationship indicates that electrical conductivity should not be neglected a priori in glaciological investigations of subglacial materials and in ground-penetrating radar (GPR) studies of saturated sediments and bedrock, even at the high end of typical linear radar frequencies used in such investigations (e.g., 100–400 MHz). Our own experience in resistivity surveying in Antarctica, combined with a literature review, suggests that a wide range of geologic materials can have electrical conductivity that is high enough to significantly impact the value of radar reflectivity. Furthermore, we have given two examples of prior studies in which inclusion of electrical conductivity in calculation of the radar bed reflectivity may provide an explanation for results that may be considered surprising if the impact of electrical conductivity on radar reflection is neglected. The commonly made assumption that only dielectric permittivity of the two media needs to be considered in interpretation of radar reflectivity can lead to erroneous conclusions. |
format |
Text |
author |
Tulaczyk, Slawek M. Foley, Neil T. |
spellingShingle |
Tulaczyk, Slawek M. Foley, Neil T. The role of electrical conductivity in radar wave reflection from glacier beds |
author_facet |
Tulaczyk, Slawek M. Foley, Neil T. |
author_sort |
Tulaczyk, Slawek M. |
title |
The role of electrical conductivity in radar wave reflection from glacier beds |
title_short |
The role of electrical conductivity in radar wave reflection from glacier beds |
title_full |
The role of electrical conductivity in radar wave reflection from glacier beds |
title_fullStr |
The role of electrical conductivity in radar wave reflection from glacier beds |
title_full_unstemmed |
The role of electrical conductivity in radar wave reflection from glacier beds |
title_sort |
role of electrical conductivity in radar wave reflection from glacier beds |
publishDate |
2020 |
url |
https://doi.org/10.5194/tc-14-4495-2020 https://tc.copernicus.org/articles/14/4495/2020/ |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-14-4495-2020 https://tc.copernicus.org/articles/14/4495/2020/ |
op_doi |
https://doi.org/10.5194/tc-14-4495-2020 |
container_title |
The Cryosphere |
container_volume |
14 |
container_issue |
12 |
container_start_page |
4495 |
op_container_end_page |
4506 |
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1766019898934296576 |