Abstrakt
Bathymetric and seismic data from the Southwest Greenland margin have
been used to provide an integrated shelf-to-basin overview of the margin
architecture between 57° N and 64° N. A variety of glacially formed
morphologic features, contour current-related erosion and sedimentary
deposits, and evidence of downslope sediment transport via canyons,
channels and gullies is found here. The study area is characterized by
two major canyons bordering Fylla Bank in the northern part and a narrow
shelf and steep slope to the south, where erosion due to strong
boundary currents occur down to c. 3000 m water depth. The narrow shelf
area appears to be an intra-ice stream area, and numerous channels and
gullies on the upper slope point to hyperpycnal melt water release from a
stable or retreating wide ice front. Further southward, the shelf is
widening and the morphology indicates dominance of former ice stream
activity. This difference in glaciation style may reflect the different
bedrock types. Sedimentary and morphologic characteristics of the Fylla
Bank canyons and some of the slope gullies and channels point to actual
cascading of dense winter water or hyperpycnal melt water flow from the
shelf. Deep-water channels at the base of the slope evidence transport
of Greenland-derived sediment to the central Labrador Sea basin and
buried channels further west indicate a former contribution to the
Northwest Atlantic Mid-Ocean Channel (NAMOC) system. However, in
contrast to widespread turbidite channels on the present seabed
bordering NAMOC to the west, east of NAMOC contourite deposits have
largely covered the deep-water tributary turbidite channels originating
from the Greenland margin.
Originalsprog | Engelsk |
---|---|
Sider (fra-til) | 89–104 |
Antal sider | 16 |
Tidsskrift | Arktos |
Vol/bind | 5 |
Udgave nummer | 2 |
DOI | |
Status | Udgivet - 2019 |
Programområde
- Programområde 5: Natur og klima