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DOI	10.1029/2023GL106284
	Slow Dynamics of Hydrate Systems Revealed by a Double BSR
	Fabre, M.; Riboulot, V.; Loncke, L.; Ker, S.; Ballas, G.; Thomas, Y.; Ion, G.; Sultan, N.
发表日期	2024
ISSN	0094-8276
EISSN	1944-8007
起始页码	51
结束页码	10
卷号	51 期号:10
英文摘要	Determining how gas hydrate distribution evolved along continental margins in the past is essential to understanding its evolution in the future. Moreover, hydrate decomposition has been linked to several catastrophic events, including some of the largest submarine landslides on Earth and the massive release of greenhouse gases into the ocean. Offshore Romania, the presence of a second bottom-simulating reflector (BSR) provides an opportunity to gain valuable insights into hydrate dynamics since the Last Glacial Period (LGP). We conducted transient modeling of hydrate thermodynamic stability by merging in-situ observations with indirect assessments of sea-bottom temperature, thermal conductivity, salinity, sedimentation rate, and sea-level variations. We reveal a strong correlation between the BSRs and the base of the Gas Hydrate Stability Zone (GHSZ) during both the present and LGP periods. The gradual evolution of the GHSZ over the past 34 ka presented here supports a conceptual model that excludes catastrophic environmental scenarios. Methane hydrate is an ice-like compound composed of a cage of water molecules enclosing a methane molecule. Hydrates can form in marine sediments along continental margins where water and methane are present under high pressure and low temperatures. As a result of climate change, hydrate melting has been linked to catastrophic events, including submarine landslides and the release of greenhouse gases into the ocean. Offshore Romania, the presence of a relic of the base of the hydrate layers formed in sediments during past glacial conditions, reveals the evolution of the hydrate stability zone since the last glacial period. The 2D modeling results have enabled us to define the area where hydrates alternately melt and reform in response to environmental changes such as rising temperatures and sea levels. Our results show that the evolution of gas-hydrate accumulations generates multiple, slow chain reactions, preventing the system from disastrous destabilization, sequentially provoking catastrophic events. A 2D modeling reveals the observed deeper secondary BSR is mostly consistent with a paleo-BSR developed during the last glacial period A paleo-BSR can only be preserved in sediments if the period of stagnation of the base of hydrate layers is sufficient to trap enough gas Although rapid environmental changes, the hydrate-free gas system reacts much more slowly preventing catastrophic submarine destabilization
英文关键词	hydrates; free gas; double BSR; modeling; last glacial period; Black Sea
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:001232835600001
来源期刊	GEOPHYSICAL RESEARCH LETTERS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/305527
作者单位	Universite de Bretagne Occidentale; Ifremer; Centre National de la Recherche Scientifique (CNRS); Centre National de la Recherche Scientifique (CNRS); Universite Perpignan Via Domitia; Centre National de la Recherche Scientifique (CNRS); Universite de Montpellier; National Institute of Marine Geology & Geoecology of Romania (GeoEcoMar)
推荐引用方式 GB/T 7714	Fabre, M.,Riboulot, V.,Loncke, L.,et al. Slow Dynamics of Hydrate Systems Revealed by a Double BSR[J],2024,51(10).
APA	Fabre, M..,Riboulot, V..,Loncke, L..,Ker, S..,Ballas, G..,...&Sultan, N..(2024).Slow Dynamics of Hydrate Systems Revealed by a Double BSR.GEOPHYSICAL RESEARCH LETTERS,51(10).
MLA	Fabre, M.,et al."Slow Dynamics of Hydrate Systems Revealed by a Double BSR".GEOPHYSICAL RESEARCH LETTERS 51.10(2024).