Benthic dynamics at the carbonate mound regions of the Porcupine Sea Bight continental margin
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A brief review is given of some dynamical processes that influence the benthic dynamics within the carbonate mound provinces located at the Porcupine Bank/Sea Bight margin, NE Atlantic. The depth range of the mounds in this region (600–1,000 m) marks the upper boundary of the Mediterranean outflow water above which Eastern North Atlantic Water dominates. Both water masses are carried northwards by the eastern boundary slope current. In the benthic boundary layer both the action of internal waves, and other tidal period baroclinic waves, may enhance the bottom currents and add to both the residual and maximum flow strength. Both residual and maximum bottom currents vary at different mound locations, with stronger currents found at Belgica (SE Porcupine Sea Bight) mound and Pelagia (NW Porcupine Bank) mound regions, whilst weakest currents are found at the Hovland and Magellan Mounds at the northern Sea Bight margin. The differences may be attributed to the presence of internal waves (Pelagia) or bottom intensified diurnal waves (Belgica). These different dynamical regimes are likely to have implications for the distribution patterns of live coral at the different locations.
KeywordsBenthic dynamics Carbonate mounds Cold corals
This work has been supported by the funding of the EU for projects ACES (contract EVK3-CT-1999-00008) and ECOMOUND (EVK3-CT-1999-00013). The Captain and Crews of all the research vessels that took part in the ACES and ECOMOUND field surveys, and those involved in previous work quoted here, are gratefully acknowledged, as are the input and many discussions with fellow project participants. Support in finalising this manuscript was also provided by the EU project HERMES (contract GOCE-CT-2005-511234-1).
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