Expedition 361: Site U1479

Abstract

Site U1479 is located on a 30 km wide morphological high rising ~200 m above the regional seafloor on the mid-to-lower western slope of the Agulhas Bank in Cape Basin (35°03.53′S; 17°24.06′E) ~85 nmi southwest of Cape Town, South Africa, at a water depth of 2615 m below sea level (mbsl). The Site U1479 primary objectives are to (1) Recover a complete Pliocene–Pleistocene sedimentary succession, including the early Pliocene warm period, mid-Pliocene expansion of Northern Hemisphere ice sheets, and the mid-Pleistocene transition, from a high-accumulation site located within the Agulhas ring corridor; (2) Reconstruct Agulhas Current warm-water transports over the course of both orbitally modulated and more abrupt climate changes; (3) Assess the linking between Antarctic climate variations, circumpolar ocean front instability, and connections with Agulhas leakage into the South Atlantic; (4) Assess the vigor and hydrography of NADW (or its precursors) exported to Circumpolar Deep Water and the southwest Indian Ocean at a location proximal to the entrance of NADW to the Southern Ocean and southern Indian Ocean; and (5) Evaluate the possibility of advective salinity feedbacks between Agulhas leakage and Atlantic Meridional Overturning Circulation variability, notably the possible role of the leakage in modulating surface-to-deep-ocean coupling in the North Atlantic during the transition between climatic states.