AFI 02/36_02 - Geochemical Tracing of Pacific-to-Atlantic Mantle Flow through the Drake Passage/Scotia Sea Gateway - Rock samples collected by dredging in the Scotia Sea, February and March 2004

Sampling was undertaken within the West Scotia Sea in an attempt to identify the boundary between the Pacific and Bouvet mantle domains and so understand, quantify and document the flow of mantle - which is important for understanding global geodynamics The JR77 cruise aimed to acquire rock samples to constrain the history of the mantle beneath the Scotia Sea, from which the oceanic crust was derived by melting. Twenty days of rock dredging were conducted at fourteen sites in five main areas. Thirteen dredges were successful in recovering oceanic rocks of mixed sizes, up to and including very large boulders and dredge paths of up to 1 km were followed. The cruise also (remarkably) recovered fresh mantle peridotite nodules from the West Scotia Ridge, the first of its type - to our knowledge - from the world's ocean ridge system.