DOI: 10.1016/j.epsl.2021.117067
论文题名: Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean
作者: Mosher D.C. ; Boggild K.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2021
卷: 569 语种: 英语
中文关键词: 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
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 Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/165608
Appears in Collections: 气候变化与战略
There are no files associated with this item.
作者单位: Geological Survey of Canada, Natural Resources Canada, 1 Challenger Drive, Dartmouth, NS B2Y 4A2, Canada
Recommended Citation:
Mosher D.C.,Boggild K.. Impact of bottom currents on deep water sedimentary processes of Canada Basin, Arctic Ocean[J]. Earth and Planetary Science Letters,2021-01-01,569