HR: 1340h
AN: OS53A-0968 [Abstracts]
TI: Investigations of the bottom current sculpted margin of Hatton Bank, NE Atlantic
AU: * MacLachlan, S E
EM: sucl@noc.soton.ac.uk
AF: UNCLOS Group, National Oceanography Centre, Southampton, SO14 3ZH, United
Kingdom
AU: Elliott, G M
EM: gme@noc.soton.ac.uk
AF: UNCLOS Group, National Oceanography Centre, Southampton, SO14 3ZH, United
Kingdom
AU: Parson, L M
EM: lmp@noc.soton.ac.uk
AF: UNCLOS Group, National Oceanography Centre, Southampton, SO14 3ZH, United
Kingdom
AB:
The NW Hatton Bank in the NE Atlantic represents a unique opportunity to examine the interaction of bottom
currents with complex seabed topography and to analyse the affects on the morphology and distribution of
sediments along the margin. The NW Hatton Bank margin is a slope located remote from any major terrigenous
sediment supply and at present is over 200 NM from the closest sediment source onshore. The data presented
in this study were collected on the research vessel R.R.S. Charles Darwin in 1999, for the purpose of determining
the outer limit of the legal continental shelf according to the United Nations Convention on the Law of the Sea.
Swath bathymetry and high resolution acoustic data allow us to evaluate both local and regional controls on slope
sedimentation and the possible mechanisms for bottom current velocity variability across a slope setting within
the NW European continental margin. The slope is characterised by an intense bottom current flow related to the
Deep Northern Boundary Current. Along the slope, bottom-current sedimentation is dominant, leading to the
development of the Hatton drift and sediment wave fields. Non-depositional and erosional features related to
bottom current activity were also identified and include moats encircling the volcanic cones and deep erosional
scours. The interaction between bottom current circulation and complex margin morphology controls the
distribution, geometry and scale of the sediment wave fields.
DE: 4200 OCEANOGRAPHY: GENERAL
DE: 4219 Continental shelf and slope processes (3002)
DE: 4243 Marginal and semi-enclosed seas
DE: 8110 Continental tectonics: general (0905)
DE: 8169 Sedimentary basin processes
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting