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Reflection profiles and hydrographic data indicate that sedimentation in parts of the northernmost Atlantic and in the Labrador basin has been largely governed by the movement of bottom water derived from the Norwegian Sea. Three areas are considered in detail. The first is the channel separating Rockall bank from the Irish continental shelf, where a ridge, nearly 600 km long, composed of sediment deposited on a gently dipping reflector of early Tertiary age, has been found. Hydrographic observations suggest that the feature, for which the name Feni ridge is proposed, is the result of deposition close to the boundary of a component of the Iceland‐Scotland overflow water from the Norwegian Sea, which enters the channel from the north and in flowing southward is constrained by Coriolis force to the Rockall scarp. Farther north, reflection profiles show a marked asymmetry of sediment distribution across the volcanic Faeroe‐Iceland ridge, the sediment cover being much thicker and more continuous on the north‐facing slope than on the crest and southern flank. This difference is attributed to fast bottom currents in the south, caused by sinking of the Norwegian Sea overflow, and the persistence of tranquil bottom conditions in the north. Seismic profiles from the Labrador basin reveal a well‐defined body of thick sediments trending NNW on a portion of the continental rise of southern Greenland where turbidity currents cannot reach. The thick sediments lie in a region in which the flow of deep water is weak and in which rapid deposition from sediment‐laden bottom waters is allowed. Appreciably stronger bottom currents associated with the counterclockwise circulation of dense water derived from the Norwegian Sea appear to have greatly inhibited deposition of pelagic material in the area surrounding the sediment body. Sedimentation under the influence of bottom currents in this region, in the Rockall area, and on the Blake‐Bahama outer ridge took place throughout a large part of Tertiary time but did not occur in the Upper Cretaceous. This is attributed to a major alteration in the circulation pattern of the North Atlantic caused by continental drift, polar wandering, and climatic deterioration between late Cretaceous and late Eocene times.

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