Release of Methane from Bering Sea Sediments During the Last Glacial Period
Several lines of evidence suggest that during times of elevated methane flux the sulfate-methane transition zone (SMTZ) was positioned near the sediment-water interface. We studied two cores (from 700 m and 1457 m water depth) from the Umnak Plateau region. Anomalously low d13C and high d18O in bent...
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ftosti:oai:osti.gov:969330 2023-07-30T04:02:40+02:00 Release of Methane from Bering Sea Sediments During the Last Glacial Period Mea Cook Lloyd Keigwin 2010-02-18 application/pdf http://www.osti.gov/servlets/purl/969330 https://www.osti.gov/biblio/969330 https://doi.org/10.2172/969330 unknown http://www.osti.gov/servlets/purl/969330 https://www.osti.gov/biblio/969330 https://doi.org/10.2172/969330 doi:10.2172/969330 03 NATURAL GAS BERING SEA CARBONATES CLIMATES FORAMINIFERA INTERSTITIALS METHANE OXIDATION SEDIMENTS SEDIMENT-WATER INTERFACES STABLE ISOTOPES WATER 2010 ftosti https://doi.org/10.2172/969330 2023-07-11T08:47:54Z Several lines of evidence suggest that during times of elevated methane flux the sulfate-methane transition zone (SMTZ) was positioned near the sediment-water interface. We studied two cores (from 700 m and 1457 m water depth) from the Umnak Plateau region. Anomalously low d13C and high d18O in benthic and planktonic foraminifera in these cores are the consequence of diagenetic overgrowths of authigenic carbonates. There are multiple layers of authigenic-carbonate-rich sediment in these cores, and the stable isotope compositions of the carbonates are consistent with those formed during anaerobic oxidation of methane (AOM). The carbonate-rich layers are associated with biomarkers produced by methane-oxidizing archaea, archaeol and glyceryl dibiphytanyl glyceryl tetraether (GDGT). The d13C of the archaeol and certain GDGTs are isotopically depleted. These carbonate- and AOM-biomarker-rich layers were emplaced in the SMTZ during episodes when there was a high flux of methane or methane-rich fluids upward in the sediment column. The sediment methane in the Umnak Plateau region appears to have been very dynamic during the glacial period, and interacted with the ocean-atmosphere system at millennial time scales. The upper-most carbonate-rich layers are in radiocarbon-dated sediment deposited during interstitials 2 and 3, 28-20 ka, and may be associated with the climate warming during this time. Other/Unknown Material Bering Sea Planktonic foraminifera SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Bering Sea Umnak Plateau ENVELOPE(-170.250,-170.250,54.250,54.250) |
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 |
03 NATURAL GAS BERING SEA CARBONATES CLIMATES FORAMINIFERA INTERSTITIALS METHANE OXIDATION SEDIMENTS SEDIMENT-WATER INTERFACES STABLE ISOTOPES WATER |
spellingShingle |
03 NATURAL GAS BERING SEA CARBONATES CLIMATES FORAMINIFERA INTERSTITIALS METHANE OXIDATION SEDIMENTS SEDIMENT-WATER INTERFACES STABLE ISOTOPES WATER Mea Cook Lloyd Keigwin Release of Methane from Bering Sea Sediments During the Last Glacial Period |
topic_facet |
03 NATURAL GAS BERING SEA CARBONATES CLIMATES FORAMINIFERA INTERSTITIALS METHANE OXIDATION SEDIMENTS SEDIMENT-WATER INTERFACES STABLE ISOTOPES WATER |
description |
Several lines of evidence suggest that during times of elevated methane flux the sulfate-methane transition zone (SMTZ) was positioned near the sediment-water interface. We studied two cores (from 700 m and 1457 m water depth) from the Umnak Plateau region. Anomalously low d13C and high d18O in benthic and planktonic foraminifera in these cores are the consequence of diagenetic overgrowths of authigenic carbonates. There are multiple layers of authigenic-carbonate-rich sediment in these cores, and the stable isotope compositions of the carbonates are consistent with those formed during anaerobic oxidation of methane (AOM). The carbonate-rich layers are associated with biomarkers produced by methane-oxidizing archaea, archaeol and glyceryl dibiphytanyl glyceryl tetraether (GDGT). The d13C of the archaeol and certain GDGTs are isotopically depleted. These carbonate- and AOM-biomarker-rich layers were emplaced in the SMTZ during episodes when there was a high flux of methane or methane-rich fluids upward in the sediment column. The sediment methane in the Umnak Plateau region appears to have been very dynamic during the glacial period, and interacted with the ocean-atmosphere system at millennial time scales. The upper-most carbonate-rich layers are in radiocarbon-dated sediment deposited during interstitials 2 and 3, 28-20 ka, and may be associated with the climate warming during this time. |
author |
Mea Cook Lloyd Keigwin |
author_facet |
Mea Cook Lloyd Keigwin |
author_sort |
Mea Cook |
title |
Release of Methane from Bering Sea Sediments During the Last Glacial Period |
title_short |
Release of Methane from Bering Sea Sediments During the Last Glacial Period |
title_full |
Release of Methane from Bering Sea Sediments During the Last Glacial Period |
title_fullStr |
Release of Methane from Bering Sea Sediments During the Last Glacial Period |
title_full_unstemmed |
Release of Methane from Bering Sea Sediments During the Last Glacial Period |
title_sort |
release of methane from bering sea sediments during the last glacial period |
publishDate |
2010 |
url |
http://www.osti.gov/servlets/purl/969330 https://www.osti.gov/biblio/969330 https://doi.org/10.2172/969330 |
long_lat |
ENVELOPE(-170.250,-170.250,54.250,54.250) |
geographic |
Bering Sea Umnak Plateau |
geographic_facet |
Bering Sea Umnak Plateau |
genre |
Bering Sea Planktonic foraminifera |
genre_facet |
Bering Sea Planktonic foraminifera |
op_relation |
http://www.osti.gov/servlets/purl/969330 https://www.osti.gov/biblio/969330 https://doi.org/10.2172/969330 doi:10.2172/969330 |
op_doi |
https://doi.org/10.2172/969330 |
_version_ |
1772813493964111872 |