Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic
We present results from a sediment core collected from a pockmark field on the Vestnesa Ridge (~ 80° N) in the eastern Fram Strait. This is the only deep-water gateway to the Arctic, and one of the northernmost marine gas hydrate provinces in the world. Eight 14C AMS dates reveal a detailed chronolo...
Published in: | Climate of the Past |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2018
|
Subjects: | |
Online Access: | https://doi.org/10.5194/cp-11-669-2015 https://cp.copernicus.org/articles/11/669/2015/ |
id |
fttriple:oai:gotriple.eu:WRZB01a7bqHqSRiQDMOjU |
---|---|
record_format |
openpolar |
spelling |
fttriple:oai:gotriple.eu:WRZB01a7bqHqSRiQDMOjU 2023-05-15T15:00:33+02:00 Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic Consolaro, C. Rasmussen, T. L. Panieri, G. Mienert, J. Bünz, S. Sztybor, K. 2018-09-27 https://doi.org/10.5194/cp-11-669-2015 https://cp.copernicus.org/articles/11/669/2015/ en eng Copernicus Publications doi:10.5194/cp-11-669-2015 10670/1.edz2w2 1814-9324 1814-9332 https://cp.copernicus.org/articles/11/669/2015/ undefined Geographica Helvetica - geography eISSN: 1814-9332 envir geo Text https://vocabularies.coar-repositories.org/resource_types/c_18cf/ Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2018 fttriple https://doi.org/10.5194/cp-11-669-2015 2023-01-22T17:52:05Z We present results from a sediment core collected from a pockmark field on the Vestnesa Ridge (~ 80° N) in the eastern Fram Strait. This is the only deep-water gateway to the Arctic, and one of the northernmost marine gas hydrate provinces in the world. Eight 14C AMS dates reveal a detailed chronology for the last 14 ka BP. The δ 13C record measured on the benthonic foraminiferal species Cassidulina neoteretis shows two distinct intervals with negative values termed carbon isotope excursion (CIE I and CIE II, respectively). The values were as low as −4.37‰ in CIE I, correlating with the Bølling–Allerød interstadials, and as low as −3.41‰ in CIE II, correlating with the early Holocene. In the Bølling–Allerød interstadials, the planktonic foraminifera also show negative values, probably indicating secondary methane-derived authigenic precipitation affecting the foraminiferal shells. After a cleaning procedure designed to remove authigenic carbonate coatings on benthonic foraminiferal tests from this event, the 13C values are still negative (as low as −2.75‰). The CIE I and CIE II occurred during periods of ocean warming, sea-level rise and increased concentrations of methane (CH4) in the atmosphere. CIEs with similar timing have been reported from other areas in the North Atlantic, suggesting a regional event. The trigger mechanisms for such regional events remain to be determined. We speculate that sea-level rise and seabed loading due to high sediment supply in combination with increased seismic activity as a result of rapid deglaciation may have triggered the escape of significant amounts of methane to the seafloor and the water column above. Article in Journal/Newspaper Arctic Foraminifera* Fram Strait North Atlantic Planktonic foraminifera Unknown Arctic Climate of the Past 11 4 669 685 |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English |
topic |
envir geo |
spellingShingle |
envir geo Consolaro, C. Rasmussen, T. L. Panieri, G. Mienert, J. Bünz, S. Sztybor, K. Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic |
topic_facet |
envir geo |
description |
We present results from a sediment core collected from a pockmark field on the Vestnesa Ridge (~ 80° N) in the eastern Fram Strait. This is the only deep-water gateway to the Arctic, and one of the northernmost marine gas hydrate provinces in the world. Eight 14C AMS dates reveal a detailed chronology for the last 14 ka BP. The δ 13C record measured on the benthonic foraminiferal species Cassidulina neoteretis shows two distinct intervals with negative values termed carbon isotope excursion (CIE I and CIE II, respectively). The values were as low as −4.37‰ in CIE I, correlating with the Bølling–Allerød interstadials, and as low as −3.41‰ in CIE II, correlating with the early Holocene. In the Bølling–Allerød interstadials, the planktonic foraminifera also show negative values, probably indicating secondary methane-derived authigenic precipitation affecting the foraminiferal shells. After a cleaning procedure designed to remove authigenic carbonate coatings on benthonic foraminiferal tests from this event, the 13C values are still negative (as low as −2.75‰). The CIE I and CIE II occurred during periods of ocean warming, sea-level rise and increased concentrations of methane (CH4) in the atmosphere. CIEs with similar timing have been reported from other areas in the North Atlantic, suggesting a regional event. The trigger mechanisms for such regional events remain to be determined. We speculate that sea-level rise and seabed loading due to high sediment supply in combination with increased seismic activity as a result of rapid deglaciation may have triggered the escape of significant amounts of methane to the seafloor and the water column above. |
format |
Article in Journal/Newspaper |
author |
Consolaro, C. Rasmussen, T. L. Panieri, G. Mienert, J. Bünz, S. Sztybor, K. |
author_facet |
Consolaro, C. Rasmussen, T. L. Panieri, G. Mienert, J. Bünz, S. Sztybor, K. |
author_sort |
Consolaro, C. |
title |
Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic |
title_short |
Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic |
title_full |
Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic |
title_fullStr |
Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic |
title_full_unstemmed |
Carbon isotope (δ13C) excursions suggest times of major methane release during the last 14 kyr in Fram Strait, the deep-water gateway to the Arctic |
title_sort |
carbon isotope (δ13c) excursions suggest times of major methane release during the last 14 kyr in fram strait, the deep-water gateway to the arctic |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/cp-11-669-2015 https://cp.copernicus.org/articles/11/669/2015/ |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Foraminifera* Fram Strait North Atlantic Planktonic foraminifera |
genre_facet |
Arctic Foraminifera* Fram Strait North Atlantic Planktonic foraminifera |
op_source |
Geographica Helvetica - geography eISSN: 1814-9332 |
op_relation |
doi:10.5194/cp-11-669-2015 10670/1.edz2w2 1814-9324 1814-9332 https://cp.copernicus.org/articles/11/669/2015/ |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/cp-11-669-2015 |
container_title |
Climate of the Past |
container_volume |
11 |
container_issue |
4 |
container_start_page |
669 |
op_container_end_page |
685 |
_version_ |
1766332647651409920 |