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Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming
Methane seepage from the upper continental slopes of Western Svalbard has previously been attributed to gas hydrate dissociation induced by anthropogenic warming of ambient bottom waters. Here we show that sediment cores drilled off Prins Karls Foreland contain freshwater from dissociating hydrates....
Autores principales: | , , , , , , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group UK
2018
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5758787/ https://www.ncbi.nlm.nih.gov/pubmed/29311564 http://dx.doi.org/10.1038/s41467-017-02550-9 |
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author | Wallmann, Klaus Riedel, M. Hong, W. L. Patton, H. Hubbard, A. Pape, T. Hsu, C. W. Schmidt, C. Johnson, J. E. Torres, M. E. Andreassen, K. Berndt, C. Bohrmann, G. |
author_facet | Wallmann, Klaus Riedel, M. Hong, W. L. Patton, H. Hubbard, A. Pape, T. Hsu, C. W. Schmidt, C. Johnson, J. E. Torres, M. E. Andreassen, K. Berndt, C. Bohrmann, G. |
author_sort | Wallmann, Klaus |
collection | PubMed |
description | Methane seepage from the upper continental slopes of Western Svalbard has previously been attributed to gas hydrate dissociation induced by anthropogenic warming of ambient bottom waters. Here we show that sediment cores drilled off Prins Karls Foreland contain freshwater from dissociating hydrates. However, our modeling indicates that the observed pore water freshening began around 8 ka BP when the rate of isostatic uplift outpaced eustatic sea-level rise. The resultant local shallowing and lowering of hydrostatic pressure forced gas hydrate dissociation and dissolved chloride depletions consistent with our geochemical analysis. Hence, we propose that hydrate dissociation was triggered by postglacial isostatic rebound rather than anthropogenic warming. Furthermore, we show that methane fluxes from dissociating hydrates were considerably smaller than present methane seepage rates implying that gas hydrates were not a major source of methane to the oceans, but rather acted as a dynamic seal, regulating methane release from deep geological reservoirs. |
format | Online Article Text |
id | pubmed-5758787 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2018 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-57587872018-01-12 Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming Wallmann, Klaus Riedel, M. Hong, W. L. Patton, H. Hubbard, A. Pape, T. Hsu, C. W. Schmidt, C. Johnson, J. E. Torres, M. E. Andreassen, K. Berndt, C. Bohrmann, G. Nat Commun Article Methane seepage from the upper continental slopes of Western Svalbard has previously been attributed to gas hydrate dissociation induced by anthropogenic warming of ambient bottom waters. Here we show that sediment cores drilled off Prins Karls Foreland contain freshwater from dissociating hydrates. However, our modeling indicates that the observed pore water freshening began around 8 ka BP when the rate of isostatic uplift outpaced eustatic sea-level rise. The resultant local shallowing and lowering of hydrostatic pressure forced gas hydrate dissociation and dissolved chloride depletions consistent with our geochemical analysis. Hence, we propose that hydrate dissociation was triggered by postglacial isostatic rebound rather than anthropogenic warming. Furthermore, we show that methane fluxes from dissociating hydrates were considerably smaller than present methane seepage rates implying that gas hydrates were not a major source of methane to the oceans, but rather acted as a dynamic seal, regulating methane release from deep geological reservoirs. Nature Publishing Group UK 2018-01-08 /pmc/articles/PMC5758787/ /pubmed/29311564 http://dx.doi.org/10.1038/s41467-017-02550-9 Text en © The Author(s) 2017 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
spellingShingle | Article Wallmann, Klaus Riedel, M. Hong, W. L. Patton, H. Hubbard, A. Pape, T. Hsu, C. W. Schmidt, C. Johnson, J. E. Torres, M. E. Andreassen, K. Berndt, C. Bohrmann, G. Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming |
title | Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming |
title_full | Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming |
title_fullStr | Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming |
title_full_unstemmed | Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming |
title_short | Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming |
title_sort | gas hydrate dissociation off svalbard induced by isostatic rebound rather than global warming |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5758787/ https://www.ncbi.nlm.nih.gov/pubmed/29311564 http://dx.doi.org/10.1038/s41467-017-02550-9 |
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