Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics
Abstract Results from the first focused heat flow study on the U.S. Beaufort Margin provide insight into decadal‐scale Arctic Ocean temperature change and raise new questions regarding Beaufort Margin evolution. This study measured heat flow using a 3.5‐m Lister probe at 103 sites oriented along fou...
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ftdoajarticles:oai:doaj.org/article:54e7e769672541078fdc76b7a3ef7d06 2023-12-03T10:16:59+01:00 Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics Matthew J. Hornbach Robert N. Harris Benjamin J. Phrampus 2020-05-01T00:00:00Z https://doi.org/10.1029/2020GC008933 https://doaj.org/article/54e7e769672541078fdc76b7a3ef7d06 EN eng Wiley https://doi.org/10.1029/2020GC008933 https://doaj.org/toc/1525-2027 1525-2027 doi:10.1029/2020GC008933 https://doaj.org/article/54e7e769672541078fdc76b7a3ef7d06 Geochemistry, Geophysics, Geosystems, Vol 21, Iss 5, Pp n/a-n/a (2020) Arctic Beaufort climate heat flow hydrate ocean temperature Geophysics. Cosmic physics QC801-809 Geology QE1-996.5 article 2020 ftdoajarticles https://doi.org/10.1029/2020GC008933 2023-11-05T01:35:57Z Abstract Results from the first focused heat flow study on the U.S. Beaufort Margin provide insight into decadal‐scale Arctic Ocean temperature change and raise new questions regarding Beaufort Margin evolution. This study measured heat flow using a 3.5‐m Lister probe at 103 sites oriented along four north‐south transects perpendicular to the ~700‐km long U.S. Beaufort Margin. The new heat flow measurements, corrected both for seasonal ocean temperature fluctuations and bathymetric effects, reveal low average heat flow values (~35 mW/m2) at seafloor depths of 300–900 m below sea level (mbsl) and anomalously high (~80 mW/m2) values at seafloor depths of >1,000 mbsl, near the predicted continent‐ocean transition. Anomalously low heat flow values measured on the upper margin are consistent with previous studies suggesting decadal‐scale ocean temperature warming to ~500 mbsl. Our results, however, indicate this ocean warming likely extends to depths as great at 900 mbsl—400 m deeper than previous studies suggest—implying widespread, ongoing, methane hydrate destabilization across much of the U.S. Beaufort Margin. The cause of the anomalously high heat flow values observed at seafloor depths >1,000 at the continent‐ocean transition is unclear. We suggest three candidate processes: (1) higher heat production and lower thermal conductivity on the margin edge due to the thickest sedimentary cover at the ocean‐continent transition, (2) seaward migrating subsurface advection, and (3) possible fault‐reactivation at the northern boundary of the Alaskan Microplate. Article in Journal/Newspaper Arctic Arctic Ocean Methane hydrate Directory of Open Access Journals: DOAJ Articles Arctic Arctic Ocean Lister ENVELOPE(-60.083,-60.083,-62.483,-62.483) Geochemistry, Geophysics, Geosystems 21 5 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Arctic Beaufort climate heat flow hydrate ocean temperature Geophysics. Cosmic physics QC801-809 Geology QE1-996.5 |
spellingShingle |
Arctic Beaufort climate heat flow hydrate ocean temperature Geophysics. Cosmic physics QC801-809 Geology QE1-996.5 Matthew J. Hornbach Robert N. Harris Benjamin J. Phrampus Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics |
topic_facet |
Arctic Beaufort climate heat flow hydrate ocean temperature Geophysics. Cosmic physics QC801-809 Geology QE1-996.5 |
description |
Abstract Results from the first focused heat flow study on the U.S. Beaufort Margin provide insight into decadal‐scale Arctic Ocean temperature change and raise new questions regarding Beaufort Margin evolution. This study measured heat flow using a 3.5‐m Lister probe at 103 sites oriented along four north‐south transects perpendicular to the ~700‐km long U.S. Beaufort Margin. The new heat flow measurements, corrected both for seasonal ocean temperature fluctuations and bathymetric effects, reveal low average heat flow values (~35 mW/m2) at seafloor depths of 300–900 m below sea level (mbsl) and anomalously high (~80 mW/m2) values at seafloor depths of >1,000 mbsl, near the predicted continent‐ocean transition. Anomalously low heat flow values measured on the upper margin are consistent with previous studies suggesting decadal‐scale ocean temperature warming to ~500 mbsl. Our results, however, indicate this ocean warming likely extends to depths as great at 900 mbsl—400 m deeper than previous studies suggest—implying widespread, ongoing, methane hydrate destabilization across much of the U.S. Beaufort Margin. The cause of the anomalously high heat flow values observed at seafloor depths >1,000 at the continent‐ocean transition is unclear. We suggest three candidate processes: (1) higher heat production and lower thermal conductivity on the margin edge due to the thickest sedimentary cover at the ocean‐continent transition, (2) seaward migrating subsurface advection, and (3) possible fault‐reactivation at the northern boundary of the Alaskan Microplate. |
format |
Article in Journal/Newspaper |
author |
Matthew J. Hornbach Robert N. Harris Benjamin J. Phrampus |
author_facet |
Matthew J. Hornbach Robert N. Harris Benjamin J. Phrampus |
author_sort |
Matthew J. Hornbach |
title |
Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics |
title_short |
Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics |
title_full |
Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics |
title_fullStr |
Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics |
title_full_unstemmed |
Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics |
title_sort |
heat flow on the u.s. beaufort margin, arctic ocean: implications for ocean warming, methane hydrate stability, and regional tectonics |
publisher |
Wiley |
publishDate |
2020 |
url |
https://doi.org/10.1029/2020GC008933 https://doaj.org/article/54e7e769672541078fdc76b7a3ef7d06 |
long_lat |
ENVELOPE(-60.083,-60.083,-62.483,-62.483) |
geographic |
Arctic Arctic Ocean Lister |
geographic_facet |
Arctic Arctic Ocean Lister |
genre |
Arctic Arctic Ocean Methane hydrate |
genre_facet |
Arctic Arctic Ocean Methane hydrate |
op_source |
Geochemistry, Geophysics, Geosystems, Vol 21, Iss 5, Pp n/a-n/a (2020) |
op_relation |
https://doi.org/10.1029/2020GC008933 https://doaj.org/toc/1525-2027 1525-2027 doi:10.1029/2020GC008933 https://doaj.org/article/54e7e769672541078fdc76b7a3ef7d06 |
op_doi |
https://doi.org/10.1029/2020GC008933 |
container_title |
Geochemistry, Geophysics, Geosystems |
container_volume |
21 |
container_issue |
5 |
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1784263936953024512 |