The Eirik Drift: a long-term barometer of North Atlantic deepwater flux south of Cape Farewell, Greenland

Abstract

AbstractThe Eirik Drift lies on the slope and rise off the southern tip of the Greenland margin where it formed under the influence of the North Atlantic deep western boundary current. The drift contains a semi-continuous and often expanded sedimentary record ranging from Early Eocene to Holocene and so contains a record of bottom current strengths over decadal to millennial time scales. These variations in current strength can be related to changes in thermohaline circulation and climate. The drift body is composed of four seismic sequences, with a number of internal discontinuities, reflecting a variety of palaeoceanographic events. Three secondary ridges are observed trending to the NW from the main ridge crest. The presence of these ridges, which have been active since the Early Pliocene, suggests that the deep current separates into three strands as it crosses the Eirik Drift, with each strand depositing a separate ridge. Variation in the degree of lateral migration within the Early to Late Pliocene sequence between ridges reflects local variation in the angle of slope on which the ridges formed. Cyclicity of reflector amplitude within the Late Pliocene to Pleistocene sequence could reflect changes in carbonate accumulation and deep current strength linked to glacial-interglacial variations.