气候变化领域集成服务门户(CCPortal): Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean

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DOI	10.1016/j.epsl.2021.117067
	Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean
	Mosher D.C.; Boggild K.
发表日期	2021
ISSN	0012821X
卷号	569
英文摘要	Canada Basin Abyssal Plain (CBAP) of the Arctic Ocean is incredibly flat and featureless at first appearance. Sediments of the basin have been interpreted to be turbidites interbedded with hemipelagic sediments. It is hypothesised, however, that deep-ocean geostrophic currents are active here as they are in most ocean basins. Compilations of modern bathymetry and subbottom profiler data are used to assess the possibility of ocean currents and their influence on sediment distribution within Canada Basin. Off of the Alaska-Beaufort margin, eastwardly deflected levees and fans in 3000 to 3800 m water depth along with oblique sediment waves on top of these features suggest a mixed system of turbidity currents influenced by cyclonic flowing geostrophic currents. These features probably formed during glaciations and lower sea level stands when the adjacent Chukchi Shelf was subaerial. Sediment delivery to the margin was likely more pronounced than today, and bottom current activity was presumably intensified. A large (100 km-wide) plastered drift and smaller bedforms were revealed by subbottom profile data along the Canadian Arctic Archipelago margin, in 3000 to 3850 m water depth. It is presumed that these deposits were formed as plumes of sediment, input through glacial outwash or outwash via the Mackenzie River. These plumes were then affected by deep contour-following currents to produce contourites. Large (up to 30 km wavelength) migrating bedforms within northern CBAP are believed to have resulted from turbidity current plumes sourced from the Mackenzie Fan that were additionally influenced by contour current reworking as part of returning cyclonic flow of deep geostrophic currents. There is little to no age control to groundtruth the stratigraphy observed in seismic profiles, but it seems likely, given their near-surface appearance, that sediment input and bottom current intensity was heavily influenced by climatic conditions related to past glaciations and associated relative sea level changes. © 2021
关键词	Arctic Ocean contourites geostrophic currents sedimentary bedforms subbottom profiler turbidites
英文关键词	Bathymetry; Glacial geology; Sea level; Sediment transport; Sedimentology; Stratigraphy; Turbidity; 'current; Abyssal plains; Arctic ocean; Bottom current; Canada basin; Contourite; Geostrophic currents; Sedimentary bedform; Subbottom profilers; Turbidite; Ocean currents; bedform; contourite; depositional environment; geostrophic flow; sedimentary rock; sedimentation; turbidite; Arctic Ocean; Canada Basin
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203230
作者单位	Geological Survey of Canada, Natural Resources Canada, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada
推荐引用方式 GB/T 7714	Mosher D.C.,Boggild K.. Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean[J],2021,569.
APA	Mosher D.C.,&Boggild K..(2021).Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean.Earth and Planetary Science Letters,569.
MLA	Mosher D.C.,et al."Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean".Earth and Planetary Science Letters 569(2021).