Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling
Destabilization of intrapermafrost gas hydrates is one of the possible mechanisms responsible for methane emission in the Arctic shelf. Intrapermafrost gas hydrates may be coeval to permafrost: they originated during regression and subsequent cooling and freezing of sediments, which created favorabl...
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Online Access: | http://earchive.tpu.ru/handle/11683/64861 https://doi.org/10.3390/geosciences9100407 |
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fttomskpuniv:oai:earchive.tpu.ru:11683/64861 2023-05-15T14:25:37+02:00 Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling Chuvilin, Evgeny Mikhaylovich Davletshina, Dinara Ekimova, Valentina Bukhanov, Boris Aleksandrovich Shakhova, Nataljya Evgenjevna Semiletov, Igor Petrovich 2019 application/pdf http://earchive.tpu.ru/handle/11683/64861 https://doi.org/10.3390/geosciences9100407 en eng MDPI AG Geosciences. 2019. Vol. 9, iss. 10 Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling / E. M. Chuvilin, D. Davletshina, V. V. Ekimova [et al.] // Geosciences. — 2019. — Vol. 9, iss. 10. — [407, 12 p.]. http://earchive.tpu.ru/handle/11683/64861 doi:10.3390/geosciences9100407 info:eu-repo/semantics/openAccess Attribution-NonCommercial 4.0 International https://creativecommons.org/licenses/by-nc/4.0/ CC-BY-NC Geosciences арктический шельф вечная мерзлота газовые гидраты arctic shelf permafrost gas hydrate temperature increase hydrate dissociation methane emission environmental impact geohazard Article info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2019 fttomskpuniv https://doi.org/10.3390/geosciences9100407 2021-03-23T17:27:54Z Destabilization of intrapermafrost gas hydrates is one of the possible mechanisms responsible for methane emission in the Arctic shelf. Intrapermafrost gas hydrates may be coeval to permafrost: they originated during regression and subsequent cooling and freezing of sediments, which created favorable conditions for hydrate stability. Local pressure increase in freezing gas-saturated sediments maintained gas hydrate stability from depths of 200–250 m or shallower. The gas hydrates that formed within shallow permafrost have survived till present in the metastable (relict) state. The metastable gas hydrates located above the present stability zone may dissociate in the case of permafrost degradation as it becomes warmer and more saline. The effect of temperature increase on frozen sand and silt containing metastable pore methane hydrate is studied experimentally to reconstruct the conditions for intrapermafrost gas hydrate dissociation. The experiments show that the dissociation process in hydrate-bearing frozen sediments exposed to warming begins and ends before the onset of pore ice melting. The critical temperature sufficient for gas hydrate dissociation varies from ?3.0 °C to ?0.3 °C and depends on lithology (particle size) and salinity of the host frozen sediments. Taking into account an almost gradientless temperature distribution during degradation of subsea permafrost, even minor temperature increases can be expected to trigger large-scale dissociation of intrapermafrost hydrates. The ensuing active methane emission from the Arctic shelf sediments poses risks of geohazard and negative environmental impacts. Article in Journal/Newspaper Arctic Arctic Ice Methane hydrate permafrost вечная мерзлота Tomsk Polytechnic University (TPU): Electronic Archive Arctic Geosciences 9 10 407 |
institution |
Open Polar |
collection |
Tomsk Polytechnic University (TPU): Electronic Archive |
op_collection_id |
fttomskpuniv |
language |
English |
topic |
арктический шельф вечная мерзлота газовые гидраты arctic shelf permafrost gas hydrate temperature increase hydrate dissociation methane emission environmental impact geohazard |
spellingShingle |
арктический шельф вечная мерзлота газовые гидраты arctic shelf permafrost gas hydrate temperature increase hydrate dissociation methane emission environmental impact geohazard Chuvilin, Evgeny Mikhaylovich Davletshina, Dinara Ekimova, Valentina Bukhanov, Boris Aleksandrovich Shakhova, Nataljya Evgenjevna Semiletov, Igor Petrovich Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling |
topic_facet |
арктический шельф вечная мерзлота газовые гидраты arctic shelf permafrost gas hydrate temperature increase hydrate dissociation methane emission environmental impact geohazard |
description |
Destabilization of intrapermafrost gas hydrates is one of the possible mechanisms responsible for methane emission in the Arctic shelf. Intrapermafrost gas hydrates may be coeval to permafrost: they originated during regression and subsequent cooling and freezing of sediments, which created favorable conditions for hydrate stability. Local pressure increase in freezing gas-saturated sediments maintained gas hydrate stability from depths of 200–250 m or shallower. The gas hydrates that formed within shallow permafrost have survived till present in the metastable (relict) state. The metastable gas hydrates located above the present stability zone may dissociate in the case of permafrost degradation as it becomes warmer and more saline. The effect of temperature increase on frozen sand and silt containing metastable pore methane hydrate is studied experimentally to reconstruct the conditions for intrapermafrost gas hydrate dissociation. The experiments show that the dissociation process in hydrate-bearing frozen sediments exposed to warming begins and ends before the onset of pore ice melting. The critical temperature sufficient for gas hydrate dissociation varies from ?3.0 °C to ?0.3 °C and depends on lithology (particle size) and salinity of the host frozen sediments. Taking into account an almost gradientless temperature distribution during degradation of subsea permafrost, even minor temperature increases can be expected to trigger large-scale dissociation of intrapermafrost hydrates. The ensuing active methane emission from the Arctic shelf sediments poses risks of geohazard and negative environmental impacts. |
format |
Article in Journal/Newspaper |
author |
Chuvilin, Evgeny Mikhaylovich Davletshina, Dinara Ekimova, Valentina Bukhanov, Boris Aleksandrovich Shakhova, Nataljya Evgenjevna Semiletov, Igor Petrovich |
author_facet |
Chuvilin, Evgeny Mikhaylovich Davletshina, Dinara Ekimova, Valentina Bukhanov, Boris Aleksandrovich Shakhova, Nataljya Evgenjevna Semiletov, Igor Petrovich |
author_sort |
Chuvilin, Evgeny Mikhaylovich |
title |
Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling |
title_short |
Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling |
title_full |
Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling |
title_fullStr |
Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling |
title_full_unstemmed |
Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling |
title_sort |
role of warming in destabilization of intrapermafrost gas hydrates in the arctic shelf: experimental modeling |
publisher |
MDPI AG |
publishDate |
2019 |
url |
http://earchive.tpu.ru/handle/11683/64861 https://doi.org/10.3390/geosciences9100407 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Arctic Ice Methane hydrate permafrost вечная мерзлота |
genre_facet |
Arctic Arctic Ice Methane hydrate permafrost вечная мерзлота |
op_source |
Geosciences |
op_relation |
Geosciences. 2019. Vol. 9, iss. 10 Role of Warming in Destabilization of Intrapermafrost Gas Hydrates in the Arctic Shelf: Experimental Modeling / E. M. Chuvilin, D. Davletshina, V. V. Ekimova [et al.] // Geosciences. — 2019. — Vol. 9, iss. 10. — [407, 12 p.]. http://earchive.tpu.ru/handle/11683/64861 doi:10.3390/geosciences9100407 |
op_rights |
info:eu-repo/semantics/openAccess Attribution-NonCommercial 4.0 International https://creativecommons.org/licenses/by-nc/4.0/ |
op_rightsnorm |
CC-BY-NC |
op_doi |
https://doi.org/10.3390/geosciences9100407 |
container_title |
Geosciences |
container_volume |
9 |
container_issue |
10 |
container_start_page |
407 |
_version_ |
1766298060858589184 |