Full page fax print - International Seabed Authority

geochemical scanner (e.g., SUAVE: NOAA/USA; ZAPS: Oregon State University/USA;
ALCHEMIST: IFREMER/France) became available which are used in a towed mode and
provide continuous (on-line) registration of various pathfinder elements for active
hydrothermal vents. The advantage over conventional hydrocast surveys is obvious as
large areas can be covered in a reconnaissance mode in relatively short periods of time.
3. SUBMERSIBLES AND ROVs
For detailed mapping of particular seafloor sites (“round truthing”), for precise
small-scale sampling, and in particular for direct sampling of hydrothermal fluids at
active black smoker chimneys, manned research submersibles and/or remotely operated
vehicles (ROVs) are required. There are currently several research submersibles available
(Table 2) that have operation depths of 400-6,500 m, which equals a pressure of 40-650 bar
or 4-65 MPa. The various submersibles commonly accommodate two pilots and one
scientist and are being launched from a mother ship. Individual dives last about 8-10
hours in total, however, dives up to more than 16 hours have been reported. Most
submersibles are equipped with two 5 to 7-function manipulators for sampling and
measurements. Remotely operated vehicles (ROVs) have several advantages over
manned submersibles including (i) longer bottom time (up to a week and more), (ii)
reduced cost, (iii) no risk for pilots and scientists. ROVs are equipped with camera/video
systems, which transfer video images via fibre-optic cable onto the ship. This enables a
larger group of scientists to participate in a dive and to discuss the selection of sampling
locations etc. Similar to submersibles, ROVs are also fitted with two robot arms for
manipulations at the seafloor. Currently, the Canadian ROPOS (Remotely Operated
Platform for Ocean Sciences) operated by the Canadian Scientific Submersible Facility,
the American JASON operated by Woods Hole Oceanographic Institution, and the French
VICTOR operated by IFREMER, are leading in this field together with the Japanese KAIKO
which has a maximum depth range of 11,000 m (Table 2)
Table 2. Research Submersibles and Remotely Operated Vehicles
Name Organisation Country Depth Capability
NAUTILE IFREMER France 6,000 m
CYANA IFREMER France 3,000 m
MIR 1 & 2 Shirshov Institute Russia 6,000 m
SHINKAI 6500 JAMSTEC Japan 6,500 m
SHINKAI 2000 JAMSTEC Japan 2,000 m
ALVIN WHOI USA 4,500 m
PISCES IV & V SOEST USA 2,000 m
PISCES - Russia 2,000 m
JAGO MPI Seewiesen Germany 400 m
94 International Seabed Authority