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  • Dredge sampling was carried out aboard the James Clark Ross (cruise no JR77 ) during Feb and Mar 2004. The dredge target area was along the eastern segments of the West Scotia Ridge, an ocean spreading centre which stopped spreading about 10 million years ago. The spreading centre has high topographic relief and contains an axial rift, which has flanks that are suitable for dredging. The plan was to map the spreading centre using the swath bathymetry system, and then to use this map to locate the best dredging sites. 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.

  • Dredging for rock samples was conducted in the West Scotia Sea during James Clark Ross cruise no JR77 between Feb and Mar 2004. The aim was 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.