To observe and document the megafauna of the deep pelagic, near-bottom and epibenthic habitats of the Charlie-Gibbs Fracture Zone of the mid-Atlantic Ridge. Comparison will be made between areas of high topographic relief and low relief. In addition, distribution of marine mammals will be documented both during the trans-Atlantic passage and during diving operations in the CGFZ.
Double dives, simultaneously using both MIR I and MIR II manned submersibles, near 52 40'N 034 50'W (area with high topographic relief, max depth ca 3600 m) and 52 05'N 036 20'W (low relief at similar depth).
MIR double dives
Each of the cruise's double dives will involve four scientists: one Russian and one US in each of the submersibles. At each dive site, the two subs will perform near-bottom visual/video transects. The directions of travel will be such that the track of one sub will be perpendicular to that of the other sub. In addition, both subs will observe and document pelagic organisms during transit downward and upward. Videotapes will be recorded continuously throughout dives. Dive parameters and other observations will also be recorded manually on dive logs.
During this cruise, distribution of marine mammals and turtles will be monitored during daylight hours by a marine mammal observer. If possible, tissue biopsy samples will be collected by crossbow for subsequent biochemical analysis. This activity will not alter the planned itinerary of the ship nor the dive schedule.