standardization of environmental data and information - International ...

they could be proud of their contributions to the advancement of
understanding.
Benthic currents
When a participant expressed surprise at the high speeds cited for
benthic currents, Morgan responded that he did not view 10cm/sec as
extreme. He had seen spikes up to 10-15 centimetres per second, whereas
the averages were certainly much lower.
Professor Craig R. Smith, with Morgan’s concurrence, remarked that
he was not comfortable with the term “benthic storm”. As the rates of 9-10
cm/sec came from 30 metres above the bottom, the flow was probably not
resuspending the sediment. Moreover, there were no transmissometry
records and thus no data on resuspended sediment. Talk of a benthic
storm was using the term liberally for a period of higher flow velocity.
Whether sediment was being resuspended and transported was an open
issue, on which harder data were required.
Another participant spoke of cliffs up to 40 m high on the seabed,
some of them overhanging and collapsing from time to time. Such periodic
movements implied the existence of slopes extending for some distance.
Notes and References
1. International Seabed Authority (2000), Regulations on prospecting and exploration
for polymetallic nodules in the area (ISBA/6/A/18) approved by the Authority on 13
July 2000, Selected Decisions and Documents of the Sixth Session 31-68.
2. United States Office of Ocean Minerals and Energy (1981), Deep seabed mining:
Final programmatic environmental impact statement (National Oceanic and
Atmospheric Administration, Washington, D.C.) vol.I, 295 pp.
3 H. Amann (1992), The Environmental Impact of Deep Sea Mining, report prepared for
the Bundesanstalt fur Geowissenschaften und Rohstoffe (BGR), Hanover, Germany.
4. United States, Code of Federal Regulations, title 15, sec. 970.701.
5. H. Amann (1992), The Environmental Impact of Deep Sea Mining, report prepared for
the Bundesanstalt fur Geowissenschaften und Rohstoffe (BGR), Hanover, Germany,
sec. iii, 91-113.
6. H. Amann (1992), The Environmental Impact of Deep Sea Mining, report prepared for
the Bundesanstalt fur Geowissenschaften und Rohstoffe (BGR), Hanover, Germany;
INTERNATIONAL SEABED AUTHORITY 140