Preface The expedition ARK XIX/3 with the German icebreaking RV ...

The current regime luff and lee side of a large drop stone has been measured before
sediments were taken at these locations around the drop stone. By doing so it is
expected to get further information about the influence of bottom currents on the
benthic fauna
C. 3 Sedimentation at the western Svålbard margin
Matthiessen, J., Kunz-Pirrung, M., Pirrung, M.
The "Hausgarten" area is located at the western Svålbard continental margin from
78°- 80° N which is characterized by a complex morphology. Plate tectonic activity and
glacial erosion and deposition led to pronounced topographic gradients with
prograding deep-sea fans, ridges and troughs, of which the Molloy Hole is the deepest
depression in the Arctic realm. Pelagic sedimentation at continental margins, in
general, is principally overprinted by a lateral influx of material from the shelves. In the
"Hausgarten" area, cross-shelf troughs off Kongsfjorden and Isfjorden are important
conduits for transport of water and sediment from the coastal area to the slope. Slope
instability may subsequently trigger gravity flows, in particular during times of low sea
level stand. The depositional conditions in the eastern Fram Strait are further
complicated by specific local conditions, related to sea-ice cover, water mass
exchange between the Arctic Ocean and the Nordic Seas, and deep-water formation
resulting in a spatial and temporal heterogeneity of sediment composition and
distribution. The northward flowing West Spitsbergen Current (WSC) may meridionally
advect lithogenic and biogenic matter from the Norwegian Sea. Sediment may be
supplied from Storfjorden south of Spitsbergen, when dense sediment-loaded cold
water cascades descend downslope and are entrained in the WSC. Bottom water
exchange may particularly occur via the "Hausgarten" area east of Hovgaard Ridge.
The Transpolardrift may transport sea ice and sediments from the Siberian Arctic to
the Fram Strait. These processes are documented in a number of geological records
from the past 10.000 to 15.000 years (Hebbeln et al., 1994; Andersen et al., 1996) but
their importance in the modern environment has not been evaluated. Sedimentological
investigations during expedition ARK XIX/3c therefore concentrated on sampling of
surface and near-surface, to study the large-scale depositional environment in the
"Hausgarten" area.
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