Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys
We have developed a surface-towed electric dipole-dipole system capable of operating in shallow water and deployable from small vessels. Our system uses electromagnetic energy from a modulated manmade source to interrogate the underlying resistivity structure of the seafloor. We used this system in...
Published in: | Journal of Geophysical Research: Solid Earth |
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Online Access: | http://www.osti.gov/servlets/purl/1539755 https://www.osti.gov/biblio/1539755 https://doi.org/10.1029/2018jb015859 |
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ftosti:oai:osti.gov:1539755 2023-07-30T04:04:04+02:00 Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys Sherman, D. Constable, S. C. 2021-09-01 application/pdf http://www.osti.gov/servlets/purl/1539755 https://www.osti.gov/biblio/1539755 https://doi.org/10.1029/2018jb015859 unknown http://www.osti.gov/servlets/purl/1539755 https://www.osti.gov/biblio/1539755 https://doi.org/10.1029/2018jb015859 doi:10.1029/2018jb015859 54 ENVIRONMENTAL SCIENCES 2021 ftosti https://doi.org/10.1029/2018jb015859 2023-07-11T09:34:54Z We have developed a surface-towed electric dipole-dipole system capable of operating in shallow water and deployable from small vessels. Our system uses electromagnetic energy from a modulated manmade source to interrogate the underlying resistivity structure of the seafloor. We used this system in the summers of 2014 and 2015 to map subsea ice-bearing permafrost on the Beaufort shelf along 200 km of coastline, from Tigvariak Island to Harrison Bay. Permafrost is resistive and was found to be anisotropic, likely due to interbedded layers of frozen and unfrozen sediment. Maps of depth to permafrost and its thickness were produced from electrical resistivity inversions and results compared to borehole logs in the area. We observed elevated resistivity values offshore the Sagavanirktok River outflow, supporting the idea that fresh groundwater flow has a preserving effect on submerged permafrost. This system provides a cost effective method that could be used to further quantify permafrost extent, provide a baseline for measurements of future degradation, and provide observational constraints to aid in permafrost modeling studies. Other/Unknown Material Ice permafrost SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Beaufort Shelf ENVELOPE(-142.500,-142.500,70.000,70.000) Journal of Geophysical Research: Solid Earth 123 9 7253 7265 |
institution |
Open Polar |
collection |
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
54 ENVIRONMENTAL SCIENCES |
spellingShingle |
54 ENVIRONMENTAL SCIENCES Sherman, D. Constable, S. C. Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
We have developed a surface-towed electric dipole-dipole system capable of operating in shallow water and deployable from small vessels. Our system uses electromagnetic energy from a modulated manmade source to interrogate the underlying resistivity structure of the seafloor. We used this system in the summers of 2014 and 2015 to map subsea ice-bearing permafrost on the Beaufort shelf along 200 km of coastline, from Tigvariak Island to Harrison Bay. Permafrost is resistive and was found to be anisotropic, likely due to interbedded layers of frozen and unfrozen sediment. Maps of depth to permafrost and its thickness were produced from electrical resistivity inversions and results compared to borehole logs in the area. We observed elevated resistivity values offshore the Sagavanirktok River outflow, supporting the idea that fresh groundwater flow has a preserving effect on submerged permafrost. This system provides a cost effective method that could be used to further quantify permafrost extent, provide a baseline for measurements of future degradation, and provide observational constraints to aid in permafrost modeling studies. |
author |
Sherman, D. Constable, S. C. |
author_facet |
Sherman, D. Constable, S. C. |
author_sort |
Sherman, D. |
title |
Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys |
title_short |
Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys |
title_full |
Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys |
title_fullStr |
Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys |
title_full_unstemmed |
Permafrost Extent on the Alaskan Beaufort Shelf From Surface-Towed Controlled-Source Electromagnetic Surveys |
title_sort |
permafrost extent on the alaskan beaufort shelf from surface-towed controlled-source electromagnetic surveys |
publishDate |
2021 |
url |
http://www.osti.gov/servlets/purl/1539755 https://www.osti.gov/biblio/1539755 https://doi.org/10.1029/2018jb015859 |
long_lat |
ENVELOPE(-142.500,-142.500,70.000,70.000) |
geographic |
Beaufort Shelf |
geographic_facet |
Beaufort Shelf |
genre |
Ice permafrost |
genre_facet |
Ice permafrost |
op_relation |
http://www.osti.gov/servlets/purl/1539755 https://www.osti.gov/biblio/1539755 https://doi.org/10.1029/2018jb015859 doi:10.1029/2018jb015859 |
op_doi |
https://doi.org/10.1029/2018jb015859 |
container_title |
Journal of Geophysical Research: Solid Earth |
container_volume |
123 |
container_issue |
9 |
container_start_page |
7253 |
op_container_end_page |
7265 |
_version_ |
1772815235970760704 |