Extract

In the narrow basin between the Faeroe Bank and the Bill Bailey Bank, seismic data demonstrate the presence of a Neogene deep-water sedimentary succession. This succession is characterized by several erosional unconformities (Fig. 1). Based purely on the number of unconformities present, it is possible that they correspond to the third order cycles of sea level change (Haq et al. 1988). However, the topography of the surrounding area, the geometry of the sediment units and the internal reflector pattern suggest that deposition and erosion of this succession is the result of bottom-water flow through the basin. A simple correlation between the observed unconformities and sea level fluctuations may therefore not be possible.

Since Miocene times, cold dense water has formed the bottom waters in the Nordic Seas (the Arctic Ocean and the Greenland-Norway Sea). On their way out of the Nordic Seas the bottom waters pass the Greenland-Scotland Ridge. Meincke (1983) estimated that 300f the dense bottom waters, formed in the Nordic Seas, flows south through the Faeroe channels (Faeroe-Shetland Channel and Faeroe Bank Channel). These channels form the deepest passage over the Greenland-Scotland Ridge, and the present threshold depth is c. 800 m.

The Faeroe channels are particularly important for the outflow of cold water from the Nordic Seas because the oceanic basement on the Faeroe-Iceland-Greenland Ridge, compared to the Greenland-Norway Sea, is rather shallow, typically < 500 m. This forces the deep cold water either to ‘climb’ over the ridge or to flow through the narrow but