Minerals Report - International Seabed Authority

like St. Stephen’s in the Kremlin area, they dubbed the area the “Kremlin
Area”. A little further from this area, they encountered a higher temperature
discharge and a cluster of black smokers venting intensively. Around these
black smokers was a mass of moving and wriggling white material. These
materials turned out to be shrimp of a new variety swarming over the active
black smokers. Each of the shrimp was about 5 centimetres and the team
initially named them ‘Rimicaris exocculata’ or ‘Dweller in the rift without
eyes’. Upon dissecting the shrimp on land, they discovered a plate with a
reflecting organ connected by nerve ganglia to the brain of the shrimp. A
chemical analysis of the organ found a compound in it called rhodopsin,
which is uniquely associated with the eyes of other animals. He informed
participants that it is speculated that the shrimp may have developed this
unique eye as an adaption to feeding on bacteria at the hot springs.
Professor Rona described another cruise that was made in 1994 to
determine what happens beneath the seafloor at the TAG mound. The vessel
used was an offshore drilling ship that was modified for drilling in the deep
ocean. Called the Joides Resolution, Professor Rona informed participants
that a consortium of 20 countries that work together on the Ocean Drilling
Programme (ODP) supports it. He further informed participants that with
great difficulty, 17 holes were drilled into these massive sulphides deposits.
Based on these drill holes, Professor Rona showed the components of the
deposits: the massive sulphide itself, the feeder zone where the hot solutions
well up, and the stock work where the minerals are deposited in a fracture
network. Professor Rona said that based on radiometric dating of the TAG
mound deposit, it had been determined that the range of dates inside the
deposit was between thousands to tens of thousands years old. He concluded
his presentation on the TAG mound by informing participants that this
massive sulphide deposit, is one of the largest seafloor deposits yet found in
the world.
Professor Rona stated that by studying these analogues in the deep
ocean basin, a very helpful key is provided to economic geologists on land.
These geologists in turn help marine geologists to explore and understand
massive sulphides that are forming on the deep seafloor. Dr. Rona compared
the assessment of a polymetallic massive sulphides deposit on land with its
counterpart on the deep seafloor. He stated that on land, geologists drill
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