1. Ocean Bottom Seismograph observations close to the junction of the East Pacific Rise and 9° S Fracture Zone. All previous deployments of the Blacknest OBS have been on the Mid-Atlantic ridge were the half-spreading rate has not exceeded about 1.5cm/year. Near 9° S the East Pacific Rise and the Mid-Atlantic ridge could throw light on the different tectonic processes involved at fast and slow-spreading ridges.
2. An extensive coring programme, supervised by Dr David Cronan of Imperial College. The main aim of the coring programme was to test the hypothesis of the selective dispersion metals from submarine hydrothermal centres. To this end a series of cores were taken along the 9° S fracture zone. Another series of cores was planned for the Bauer Deep, to determine whether these sediments originated on the East Pacific Rise crest and were transported to their present situation or whether they are of local volcanic origin. Finally, a traverse between the East Pacific Rise crest and the South American coast was planned for the benefit of Roy Chester of Liverpool University.
Tim J G Francis (Institute of Oceanographic Sciences Wormley Laboratory)