Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System
Gas hydrate (GH) systems constitute methane sinks sensitive to environmental changes such as pressure, temperature, and salinity. It remains a matter of debate as to whether the large GH system of the Black Sea has reached a steady state since the last glacial maximum (LGM). We report on an irregula...
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fttriple:oai:gotriple.eu:10670/1.nkscw2 2023-05-15T17:12:11+02:00 Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System Colin, Florent Ker, Stephan Riboulot, Vincent Sultan, Nabil 2020-01-01 https://doi.org/10.1029/2020GL089906 https://archimer.ifremer.fr/doc/00652/76430/77526.pdf https://archimer.ifremer.fr/doc/00652/76430/77527.docx en eng American Geophysical Union doi:10.1029/2020GL089906 10670/1.nkscw2 https://archimer.ifremer.fr/doc/00652/76430/77526.pdf https://archimer.ifremer.fr/doc/00652/76430/77527.docx other Archimer, archive institutionnelle de l'Ifremer Geophysical Research Letters (0094-8276) (American Geophysical Union), 2020-10 , Vol. 47 , N. 20 , P. e2020GL089906 (10p.) envir geo Text https://vocabularies.coar-repositories.org/resource_types/c_18cf/ 2020 fttriple https://doi.org/10.1029/2020GL089906 2023-01-22T17:38:28Z Gas hydrate (GH) systems constitute methane sinks sensitive to environmental changes such as pressure, temperature, and salinity. It remains a matter of debate as to whether the large GH system of the Black Sea has reached a steady state since the last glacial maximum (LGM). We report on an irregular free gas distribution in specific sediment layers marking an irregular bottom‐simulating reflector (BSR). This anomalous free gas distribution revealed by very high resolution seismic images, acquired by a deep‐towed multichannel seismic system, might be evidence of an on‐going migration of the base of the GH stability zone (GHSZ). We show that the reequilibrium is not occurring homogeneously as overpressure from hydrate dissociation slows their decomposition in specific sedimentary layers. The Black Sea example highlights that dissociation and the associated methane release in the water column or even in the atmosphere could be largely delayed by overpressure accumulation. Plain Language Summary Methane hydrate is an ice‐like compound composed of a cage of water molecules enclosing a methane molecule. Hydrates can form where water and methane are present under high pressure and low temperatures, for example in deep‐sea sediments. As a result of climate change (e.g., seawater temperature increase), hydrates can melt and release free gas and water. Yet we observe hydrates present where they should have melted according to modeling. We explain this irregular melting by differing properties of the host sediments and different quantities of hydrate in the sediments. Methane in the Earth’s atmosphere is a strong greenhouse gas. The release of methane from hydrate melting has been proposed as a runaway process where the methane released increases global warming, which further increases hydrate melting and methane release, repeating the cycle. Our results show that the destabilization of a hydrate system is actually a slow process, spanning several millennia. As such, a catastrophic destabilization of a gas hydrate system ... Text Methane hydrate Unknown Geophysical Research Letters 47 20 |
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envir geo Colin, Florent Ker, Stephan Riboulot, Vincent Sultan, Nabil Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System |
topic_facet |
envir geo |
description |
Gas hydrate (GH) systems constitute methane sinks sensitive to environmental changes such as pressure, temperature, and salinity. It remains a matter of debate as to whether the large GH system of the Black Sea has reached a steady state since the last glacial maximum (LGM). We report on an irregular free gas distribution in specific sediment layers marking an irregular bottom‐simulating reflector (BSR). This anomalous free gas distribution revealed by very high resolution seismic images, acquired by a deep‐towed multichannel seismic system, might be evidence of an on‐going migration of the base of the GH stability zone (GHSZ). We show that the reequilibrium is not occurring homogeneously as overpressure from hydrate dissociation slows their decomposition in specific sedimentary layers. The Black Sea example highlights that dissociation and the associated methane release in the water column or even in the atmosphere could be largely delayed by overpressure accumulation. Plain Language Summary Methane hydrate is an ice‐like compound composed of a cage of water molecules enclosing a methane molecule. Hydrates can form where water and methane are present under high pressure and low temperatures, for example in deep‐sea sediments. As a result of climate change (e.g., seawater temperature increase), hydrates can melt and release free gas and water. Yet we observe hydrates present where they should have melted according to modeling. We explain this irregular melting by differing properties of the host sediments and different quantities of hydrate in the sediments. Methane in the Earth’s atmosphere is a strong greenhouse gas. The release of methane from hydrate melting has been proposed as a runaway process where the methane released increases global warming, which further increases hydrate melting and methane release, repeating the cycle. Our results show that the destabilization of a hydrate system is actually a slow process, spanning several millennia. As such, a catastrophic destabilization of a gas hydrate system ... |
format |
Text |
author |
Colin, Florent Ker, Stephan Riboulot, Vincent Sultan, Nabil |
author_facet |
Colin, Florent Ker, Stephan Riboulot, Vincent Sultan, Nabil |
author_sort |
Colin, Florent |
title |
Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System |
title_short |
Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System |
title_full |
Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System |
title_fullStr |
Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System |
title_full_unstemmed |
Irregular BSR: Evidence of an Ongoing Reequilibrium of a Gas Hydrate System |
title_sort |
irregular bsr: evidence of an ongoing reequilibrium of a gas hydrate system |
publisher |
American Geophysical Union |
publishDate |
2020 |
url |
https://doi.org/10.1029/2020GL089906 https://archimer.ifremer.fr/doc/00652/76430/77526.pdf https://archimer.ifremer.fr/doc/00652/76430/77527.docx |
genre |
Methane hydrate |
genre_facet |
Methane hydrate |
op_source |
Archimer, archive institutionnelle de l'Ifremer Geophysical Research Letters (0094-8276) (American Geophysical Union), 2020-10 , Vol. 47 , N. 20 , P. e2020GL089906 (10p.) |
op_relation |
doi:10.1029/2020GL089906 10670/1.nkscw2 https://archimer.ifremer.fr/doc/00652/76430/77526.pdf https://archimer.ifremer.fr/doc/00652/76430/77527.docx |
op_rights |
other |
op_doi |
https://doi.org/10.1029/2020GL089906 |
container_title |
Geophysical Research Letters |
container_volume |
47 |
container_issue |
20 |
_version_ |
1766068970618617856 |