Pulse Transmission through Frozen Silt
An important objective of geophysical exploration in permafrost regions is the delineation of subsurface ground ice. Recent studies have reported on the use of ground-penetrating radar to detect massive ground ice. VHF-band radiowave short pulses were transmitted within the permafrost tunnel at Fox,...
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ftdtic:ADA147108 2023-05-15T16:36:41+02:00 Pulse Transmission through Frozen Silt Arcone,S A COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH 1984-07 text/html http://www.dtic.mil/docs/citations/ADA147108 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA147108 en eng http://www.dtic.mil/docs/citations/ADA147108 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Snow Ice and Permafrost Electromagnetic Pulses *WAVE PROPAGATION *RADAR PULSES *MICROWAVE TRANSMISSION *SILT *PERMAFROST GROUND LEVEL ALASKA COLD REGIONS TUNNELS DIELECTRIC PROPERTIES ICE SUBSURFACE SHORT PULSES ULTRAHIGH FREQUENCY PE61102A AST24 WU005 Text 1984 ftdtic 2016-02-20T23:25:53Z An important objective of geophysical exploration in permafrost regions is the delineation of subsurface ground ice. Recent studies have reported on the use of ground-penetrating radar to detect massive ground ice. VHF-band radiowave short pulses were transmitted within the permafrost tunnel at Fox, Alaska, over distances between 2.2 and 10.5 m. The propagation medium was a frozen silt containing both disseminated and massive ice with temperatures varying from -7 C near the transmitter to probably -2 C near the center of the tunnel overburden. The short pulses underwent practically no dispersion in the coldest zones but did disperse and refract through the warmer overburden, as suggested by calculations of the effectiive dielectric constant. Most significantly the measured frequency content decreased as the effective dielectric constant increased. The results indicate that deep, cross-borehole pulse transmissions over distances greater than 10 m might be possible, especially when the ground is no warmer than -4 C. The information thus gained could be used for identifying major subsurface variations, including ground ice features. Text Ice permafrost Alaska Defense Technical Information Center: DTIC Technical Reports database |
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Open Polar |
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Defense Technical Information Center: DTIC Technical Reports database |
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English |
topic |
Snow Ice and Permafrost Electromagnetic Pulses *WAVE PROPAGATION *RADAR PULSES *MICROWAVE TRANSMISSION *SILT *PERMAFROST GROUND LEVEL ALASKA COLD REGIONS TUNNELS DIELECTRIC PROPERTIES ICE SUBSURFACE SHORT PULSES ULTRAHIGH FREQUENCY PE61102A AST24 WU005 |
spellingShingle |
Snow Ice and Permafrost Electromagnetic Pulses *WAVE PROPAGATION *RADAR PULSES *MICROWAVE TRANSMISSION *SILT *PERMAFROST GROUND LEVEL ALASKA COLD REGIONS TUNNELS DIELECTRIC PROPERTIES ICE SUBSURFACE SHORT PULSES ULTRAHIGH FREQUENCY PE61102A AST24 WU005 Arcone,S A Pulse Transmission through Frozen Silt |
topic_facet |
Snow Ice and Permafrost Electromagnetic Pulses *WAVE PROPAGATION *RADAR PULSES *MICROWAVE TRANSMISSION *SILT *PERMAFROST GROUND LEVEL ALASKA COLD REGIONS TUNNELS DIELECTRIC PROPERTIES ICE SUBSURFACE SHORT PULSES ULTRAHIGH FREQUENCY PE61102A AST24 WU005 |
description |
An important objective of geophysical exploration in permafrost regions is the delineation of subsurface ground ice. Recent studies have reported on the use of ground-penetrating radar to detect massive ground ice. VHF-band radiowave short pulses were transmitted within the permafrost tunnel at Fox, Alaska, over distances between 2.2 and 10.5 m. The propagation medium was a frozen silt containing both disseminated and massive ice with temperatures varying from -7 C near the transmitter to probably -2 C near the center of the tunnel overburden. The short pulses underwent practically no dispersion in the coldest zones but did disperse and refract through the warmer overburden, as suggested by calculations of the effectiive dielectric constant. Most significantly the measured frequency content decreased as the effective dielectric constant increased. The results indicate that deep, cross-borehole pulse transmissions over distances greater than 10 m might be possible, especially when the ground is no warmer than -4 C. The information thus gained could be used for identifying major subsurface variations, including ground ice features. |
author2 |
COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH |
format |
Text |
author |
Arcone,S A |
author_facet |
Arcone,S A |
author_sort |
Arcone,S A |
title |
Pulse Transmission through Frozen Silt |
title_short |
Pulse Transmission through Frozen Silt |
title_full |
Pulse Transmission through Frozen Silt |
title_fullStr |
Pulse Transmission through Frozen Silt |
title_full_unstemmed |
Pulse Transmission through Frozen Silt |
title_sort |
pulse transmission through frozen silt |
publishDate |
1984 |
url |
http://www.dtic.mil/docs/citations/ADA147108 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA147108 |
genre |
Ice permafrost Alaska |
genre_facet |
Ice permafrost Alaska |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA147108 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
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1766027015176060928 |