Minerals Report - International Seabed Authority

CHAPTER 7
TECHNICAL REQUIREMENTS FOR THE EXPLORATION AND MINING
OF SEAFLOOR MASSIVE SULPHIDES DEPOSITS AND COBALT-RICH
FERROMANGANESE CRUSTS
Dr. Peter Herzig, Professor, Lehrstuhl für Lagerstattenlehre
Institut für Mineralogie, Brennhausgasse, Germany
Mr. Sven Petersen, Research Associate
Technical Institute for Mining and Technology
Brennhausgasse, Germany
During the past decade, marine mineral exploration programmes have
been significantly enhanced through the development and availability of
state-of-the-art exploration tools and equipment. Today, multi-purpose
research vessels with swath mapping capabilities, deep-towed camera and
video systems, TV-guided grab samplers, as well as deep-diving submersibles
and remotely operated vehicles (ROVs) are almost routinely used. A first
order technical requirement for a new era of scientific research and resource
assessment of polymetallic massive sulphides deposits is the availability of
portable seafloor drilling and coring devices which can be deployed from a
research vessel rather than a specifically designed drill ship. So far, most
research results and resource assessments are based on surface samples only
and thus are not sufficiently reliable. The development of mining systems for
massive sulphides and precious metal deposits needs to focus on continuous
recovery through rotating cutter heads and airlift of an ore slurry to the
mining vessel. Recovery technologies for cobalt-rich ferromanganese
including hydro jet and heavy-duty rollers need to be tested in order to
demonstrate that the crusts can be efficiently separated from the substrate
rock.
1. Introduction
Since the discovery of black smokers, massive sulphides and vent
biota in 1979 1 , numerous academic and government institutions carry out
exploration for seafloor massive sulphides deposits at oceanic spreading
centres worldwide. Leading countries in this field are the United States,
INTERNATIONAL SEABED AUTHORITY 303