Minerals Report - International Seabed Authority

Another unexpected surprise was the discovery of a dense and
spectacular biological community at 2000 metres depth, under pitch darkness.
An oasis of life was found with new forms of life such as the giant
tubeworms, which grow about as high as a person and grew in a shell-like
casing made of the same material as our fingernails. Many new features to
this body were found in the cracks between the lava flows. There were clams
growing to exceptionally large sizes in an environment where the hot spring
discharges were enriched in hydrogen sulphide. As a result of a high level of
haemoglobin in their blood to extract oxygen from this toxic environment
these clams have become adapted to the environment. Research on these
animals will help in the studies of survival in toxic environments, he said.
With regard to support for this ecosystem, Professor Rona explained
that bacterial material was blowing out and accumulating like a snowfall over
the sea floor in these hot spring areas. It has now been found out that these
bacteria are using chemicals, particularly the hydrogen sulphide that is
dissolved in the hot springs from the underlying rocks, as an energy source to
grab carbon, hydrogen and oxygen from the surrounding water and combine
them into carbohydrate, sugar and starches to sustain themselves and the
higher forms that live on the bacteria such as the tube worms. Thus it was not
only just an oasis of life on the deep sea floor, but also an oasis of life that is
distinct from the life on the surface of land, which is dependent on the energy
from the sun with green plants using that energy to manufacture their food at
the base of the food chain.
Professor Rona also explained through slides that some white spots
growing like flowers on the sea floor in these hot spring areas are nourished
by bacteria growing in warm water coming up through cracks. During the
dive, dome shaped chimneys several metres high were encountered,
discharging blue-white smoke. These were named “ white smokers”. The
area in which they were found was dubbed as the 'Kremlin Area' because they
reminded the scientists of the domes on the Old Russian churches. Higher
temperature discharges were also encountered and at the very edge of a
cluster of black smokers at the very top of a particular mound, a mass of white
material could be seen. Professor Rona further went on to explain that black
smokers discharge very turbulently, engulf surrounding cold water which is
near freezing, with the result that temperature drops very rapidly. Within a
INTERNATIONAL SEABED AUTHORITY 19