Contourite drifts and canyon-channel systems on the Northern Antarctic Peninsula Pacific margin

Abstract

Contourite drifts, also known as sediment drifts, result from near-bottom currents usually flowing in deep water in response to thermohaline and wind-driven circulation (Faugeres & Stow 2008). They are present throughout the world’s oceans and can be found anywhere from the abyssal floor to outer shelf settings. Contourite drifts typically display elongate mounded shapes with sizes ranging from tens to hundreds of square kilometres. In high latitudes the development of contourite drifts is favoured by the formation of cold dense waters and the delivery of large volumes of sediment by fast-flowing ice streams on the outer shelf during glacial periods (McGinnis & Hayes 1995). Several large sedimentary mounds, interpreted as sediment drifts, are located along the Pacific margin of the Antarctic Peninsula upper continental rise (Fig. 1b). These mounds have been interpreted as contourite drifts produced by SW-flowing bottom currents redistributing the fine-grained component of channelized turbidity currents (Rebesco et al. 1996; Amblas et al. 2006). The sediment drifts contain climatic and oceanographic information valuable for the reconstruction of Neogene Antarctic …