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Title: Seepage from an arctic shallow marine gas hydrate reservoir is insensitive to momentary ocean warming

Abstract

Arctic gas hydrate reservoirs located in shallow water and proximal to the sediment-water interface are thought to be sensitive to bottom water warming that may trigger gas hydrate dissociation and the release of methane. Here, we evaluate bottom water temperature as a potential driver for hydrate dissociation and methane release from a recently discovered, gas-hydrate-bearing system south of Spitsbergen (Storfjordrenna, ~380m water depth). Modelling of the non-steady-state porewater profiles and observations of distinct layers of methane-derived authigenic carbonate nodules in the sediments indicate centurial to millennial methane emissions in the region. The results of temperature modelling suggest limited impact of short-term warming on gas hydrates deeper than a few metres in the sediments. We conclude that the ongoing and past methane emission episodes at the investigated sites are likely due to the episodic ventilation of deep reservoirs rather than warming-induced gas hydrate dissociation in this shallow water seep site.

Authors:
 [1];  [2]; ORCiD logo [1];  [3];  [1];  [1];  [1]
  1. UiT The Artic Univ. of Norway, Tromso (Norway). Centre for Arctic Gas Hydrate (CAGE)
  2. Oregon State Univ., Corvallis, OR (United States). College of Earth, Ocean, and Atmospheric Sciences (CEOAS)
  3. Geological Survey of Norway, Trondheim (Norway)
Publication Date:
Research Org.:
Oregon State Univ., Corvallis, OR (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1374892
Grant/Contract Number:
FE0013531
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; carbon cycle; environmental impact

Citation Formats

Hong, Wei-Li, Torres, Marta E., Carroll, JoLynn, Crémière, Antoine, Panieri, Giuliana, Yao, Haoyi, and Serov, Pavel. Seepage from an arctic shallow marine gas hydrate reservoir is insensitive to momentary ocean warming. United States: N. p., 2017. Web. doi:10.1038/ncomms15745.
Hong, Wei-Li, Torres, Marta E., Carroll, JoLynn, Crémière, Antoine, Panieri, Giuliana, Yao, Haoyi, & Serov, Pavel. Seepage from an arctic shallow marine gas hydrate reservoir is insensitive to momentary ocean warming. United States. doi:10.1038/ncomms15745.
Hong, Wei-Li, Torres, Marta E., Carroll, JoLynn, Crémière, Antoine, Panieri, Giuliana, Yao, Haoyi, and Serov, Pavel. Wed . "Seepage from an arctic shallow marine gas hydrate reservoir is insensitive to momentary ocean warming". United States. doi:10.1038/ncomms15745. https://www.osti.gov/servlets/purl/1374892.
@article{osti_1374892,
title = {Seepage from an arctic shallow marine gas hydrate reservoir is insensitive to momentary ocean warming},
author = {Hong, Wei-Li and Torres, Marta E. and Carroll, JoLynn and Crémière, Antoine and Panieri, Giuliana and Yao, Haoyi and Serov, Pavel},
abstractNote = {Arctic gas hydrate reservoirs located in shallow water and proximal to the sediment-water interface are thought to be sensitive to bottom water warming that may trigger gas hydrate dissociation and the release of methane. Here, we evaluate bottom water temperature as a potential driver for hydrate dissociation and methane release from a recently discovered, gas-hydrate-bearing system south of Spitsbergen (Storfjordrenna, ~380m water depth). Modelling of the non-steady-state porewater profiles and observations of distinct layers of methane-derived authigenic carbonate nodules in the sediments indicate centurial to millennial methane emissions in the region. The results of temperature modelling suggest limited impact of short-term warming on gas hydrates deeper than a few metres in the sediments. We conclude that the ongoing and past methane emission episodes at the investigated sites are likely due to the episodic ventilation of deep reservoirs rather than warming-induced gas hydrate dissociation in this shallow water seep site.},
doi = {10.1038/ncomms15745},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Wed Jun 07 00:00:00 EDT 2017},
month = {Wed Jun 07 00:00:00 EDT 2017}
}

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Cited by: 3works
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