High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom
Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general interest in deeper stratigraphy and the difficulty of extensive profiling over rough snow surfaces....
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ftportlandstate:oai:pdxscholar.library.pdx.edu:geology_fac-1099 2023-05-15T13:52:18+02:00 High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom Dugan, Hilary A. Arcone, Steven A. Obryk, Maciej K. Doran, Peter T. 2016-01-01T08:00:00Z application/pdf https://pdxscholar.library.pdx.edu/geology_fac/100 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1099&context=geology_fac unknown PDXScholar https://pdxscholar.library.pdx.edu/geology_fac/100 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1099&context=geology_fac Geology Faculty Publications and Presentations Hydrogeology Cryosphere Antarctica Geophysical surveys Soil surveys -- Geophysical methods McMurdo Dry Valleys (Antarctica) Ground penetrating radar Geology Glaciology text 2016 ftportlandstate 2022-01-09T19:40:05Z Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general interest in deeper stratigraphy and the difficulty of extensive profiling over rough snow surfaces. Our goal was to find further information on the origin of the deposition and formation of intra-ice layers, bottom topography, and subbottom deposits using GPR with pulses centered near 850 MHz on two permanently ice-covered lakes in the Mc- Murdo Dry Valleys, Antarctica. The profiles were obtained using a one-person sled operation over Lake Bonney, which is typical of lakes in the region, having an ice thickness that ranges between 3 and 5 m, and Lake Vida, where the maximum ice depth is at least 27 m. Lake Bonney exhibits a semicontinuous sediment horizon at approximately a 2-m depth and several minor horizons. In contrast, Lake Vida contains unconformably eroded and folded continuous reflection horizons, packages of minor horizons between major horizons, evidence of incised fluvial deposition along the bottom, and subbottom penetration of at least 4.5 m in some areas. Where the ice thickness is less than 20 m, the lake is frozen to the bottom. Most horizon waveform phase attributes indicate relatively lower permittivity than in the surrounding matrix. Consequently, we interpreted these strata to be caused by layers of pure ice embedded within a salty and dirty ice matrix, which were formed during minor flooding. These findings supported previous conclusions that Lake Vida ice formed from surface runoff in combination with periods of ablation. Text Antarc* Antarctica McMurdo Dry Valleys Portland State University: PDXScholar Bonney ENVELOPE(162.417,162.417,-77.717,-77.717) Lake Bonney ENVELOPE(-25.588,-25.588,-80.361,-80.361) Lake Vida ENVELOPE(161.950,161.950,-77.383,-77.383) McMurdo Dry Valleys |
institution |
Open Polar |
collection |
Portland State University: PDXScholar |
op_collection_id |
ftportlandstate |
language |
unknown |
topic |
Hydrogeology Cryosphere Antarctica Geophysical surveys Soil surveys -- Geophysical methods McMurdo Dry Valleys (Antarctica) Ground penetrating radar Geology Glaciology |
spellingShingle |
Hydrogeology Cryosphere Antarctica Geophysical surveys Soil surveys -- Geophysical methods McMurdo Dry Valleys (Antarctica) Ground penetrating radar Geology Glaciology Dugan, Hilary A. Arcone, Steven A. Obryk, Maciej K. Doran, Peter T. High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom |
topic_facet |
Hydrogeology Cryosphere Antarctica Geophysical surveys Soil surveys -- Geophysical methods McMurdo Dry Valleys (Antarctica) Ground penetrating radar Geology Glaciology |
description |
Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general interest in deeper stratigraphy and the difficulty of extensive profiling over rough snow surfaces. Our goal was to find further information on the origin of the deposition and formation of intra-ice layers, bottom topography, and subbottom deposits using GPR with pulses centered near 850 MHz on two permanently ice-covered lakes in the Mc- Murdo Dry Valleys, Antarctica. The profiles were obtained using a one-person sled operation over Lake Bonney, which is typical of lakes in the region, having an ice thickness that ranges between 3 and 5 m, and Lake Vida, where the maximum ice depth is at least 27 m. Lake Bonney exhibits a semicontinuous sediment horizon at approximately a 2-m depth and several minor horizons. In contrast, Lake Vida contains unconformably eroded and folded continuous reflection horizons, packages of minor horizons between major horizons, evidence of incised fluvial deposition along the bottom, and subbottom penetration of at least 4.5 m in some areas. Where the ice thickness is less than 20 m, the lake is frozen to the bottom. Most horizon waveform phase attributes indicate relatively lower permittivity than in the surrounding matrix. Consequently, we interpreted these strata to be caused by layers of pure ice embedded within a salty and dirty ice matrix, which were formed during minor flooding. These findings supported previous conclusions that Lake Vida ice formed from surface runoff in combination with periods of ablation. |
format |
Text |
author |
Dugan, Hilary A. Arcone, Steven A. Obryk, Maciej K. Doran, Peter T. |
author_facet |
Dugan, Hilary A. Arcone, Steven A. Obryk, Maciej K. Doran, Peter T. |
author_sort |
Dugan, Hilary A. |
title |
High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom |
title_short |
High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom |
title_full |
High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom |
title_fullStr |
High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom |
title_full_unstemmed |
High-Resolution Ground-Penetrating Radar Profiles of Perennial Lake Ice in the McMurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, and Subbottom |
title_sort |
high-resolution ground-penetrating radar profiles of perennial lake ice in the mcmurdo dry valleys, antarctica: horizon attributes, unconformities, and subbottom |
publisher |
PDXScholar |
publishDate |
2016 |
url |
https://pdxscholar.library.pdx.edu/geology_fac/100 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1099&context=geology_fac |
long_lat |
ENVELOPE(162.417,162.417,-77.717,-77.717) ENVELOPE(-25.588,-25.588,-80.361,-80.361) ENVELOPE(161.950,161.950,-77.383,-77.383) |
geographic |
Bonney Lake Bonney Lake Vida McMurdo Dry Valleys |
geographic_facet |
Bonney Lake Bonney Lake Vida McMurdo Dry Valleys |
genre |
Antarc* Antarctica McMurdo Dry Valleys |
genre_facet |
Antarc* Antarctica McMurdo Dry Valleys |
op_source |
Geology Faculty Publications and Presentations |
op_relation |
https://pdxscholar.library.pdx.edu/geology_fac/100 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1099&context=geology_fac |
_version_ |
1766256593131798528 |