DOI: 10.1038/ngeo2232
论文题名: Widespread methane leakage from the sea floor on the northern US Atlantic margin
作者: Skarke A. ; Ruppel C. ; Kodis M. ; Brothers D. ; Lobecker E.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2014
卷: 7, 期: 9 起始页码: 657
结束页码: 661
语种: 英语
英文摘要: Methane emissions from the sea floor affect methane inputs into the atmosphere, ocean acidification and de-oxygenation, the distribution of chemosynthetic communities and energy resources. Global methane flux from seabed cold seeps has only been estimated for continental shelves, at 8 to 65 Tg CH 4 yr -1, yet other parts of marine continental margins are also emitting methane. The US Atlantic margin has not been considered an area of widespread seepage, with only three methane seeps recognized seaward of the shelf break. However, massive upper-slope seepage related to gas hydrate degradation has been predicted for the southern part of this margin, even though this process has previously only been recognized in the Arctic. Here we use multibeam water-column backscatter data that cover 94,000 km 2 of sea floor to identify about 570 gas plumes at water depths between 50 and 1,700 m between Cape Hatteras and Georges Bank on the northern US Atlantic passive margin. About 440 seeps originate at water depths that bracket the updip limit for methane hydrate stability. Contemporary upper-slope seepage there may be triggered by ongoing warming of intermediate waters, but authigenic carbonates observed imply that emissions have continued for more than 1,000 years at some seeps. Extrapolating the upper-slope seep density on this margin to the global passive margin system, we suggest that tens of thousands of seeps could be discoverable. © 2014 Macmillan Publishers Limited. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/106617
Appears in Collections: 气候减缓与适应 科学计划与规划
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作者单位: Department of Geosciences, Mississippi State University, Mississippi State, MS 39762, United States; US Geological Survey, Woods Hole, MS 02543, United States; Department of Geological Sciences, Brown University, Providence, RI 02912, United States; US Geological Survey, Santa Cruz, CA 95060, United States; Earth Resources Technology Inc, Laurel, MD 20707, United States
Recommended Citation:
Skarke A.,Ruppel C.,Kodis M.,et al. Widespread methane leakage from the sea floor on the northern US Atlantic margin[J]. Nature Geoscience,2014-01-01,7(9)