Ocean-current controlled sedimentation: the Lofoten Contourite Drift, Norwegian Sea

Abstract

Sediment deposition from ocean-bottom or contour currents leads to the development of contourite drifts. On the continental slope offshore of Norway, contourite drifts have developed from sediment deposition from the alongslope-flowing Norwegian Current which brings warm and saline water masses into the Norwegian Sea. The present pattern of circulation of the Norwegian–Greenland Sea water masses developed as a result of the opening of the Fram Strait separating Greenland and Svalbard to the north from the general subsidence of the Greenland–Scotland Ridge to the south (e.g. Laberg et al. 2005). The Lofoten Contourite Drift is located on the continental slope offshore of northern Norway (Fig. 1). It is a mounded, elongate, separated giant drift ( sensu Faugeres et al. 1999) up to 360 m thick, about 150 km long (along drift axis) and is characterized by a layered, continuous, parallel to slightly divergent seismic signature of medium-amplitude reflections (Fig. 1d). The uppermost part of the drift includes mainly homogeneous or bioturbated mud and sandy mud that is …