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OST-9B: Marine Minerals Development
THE WORLD COBALT MARKET AND THE POTENTIALLY PRICE STABILIZING ROLE OF HIGH-COBALT MID PACIFIC MANGANESE CRUSTS
John C. Wiltshire
 
Hawaii Undersea Research Laboratory, University of Hawaii Honolulu, Hawaii, USA
johnw@soest.hawaii.edu
 
The world cobalt market is probably the single most volatile non-precious metal market in the world. It has been characterized by price fluctuations over more than an order of magnitude, in the last two decades. These rapid shifts continue, although are dampened somewhat by current internet sales and producer contracts to a relatively large number of totally independent end users. For the cobalt end user, the metal usually represents a relatively small cost in relationship to the final cost of the product produced with the cobalt. On the other hand, the cobalt producer is faced with the threat of substitution particularly by nickel. This has kept the cobalt price on the decline in the last two years in spite of considerable growth of the world market, now at 35,000 tons per year. The cobalt market is continuing to grow at a high rate and with the advent of electric cars (which use large amounts of cobalt in their batteries), this growth is expected to accelerate. Faced with an expanding but insecure market, the cobalt mining community is looking for stable, competitive, long-term sources of cobalt. A large number of new cobalt mining project are under consideration world-wide.
 
In this light, the marine cobalt resource in the Mid Pacific becomes significant. Detailed work will be discussed on the cobalt-rich manganese crusts in the Marshall Islands and around Johnston Island. Microstratigraphy, of Johnston Island crusts, was performed with upper layers containing as much as 1.6% cobalt. Total cobalt in many crust samples was above 1%. Collectively these resources represent millions of tons of potentially viable cobalt production. New AUV and ROV developments make these resources attractive on the 20-30 year time horizon. This is the same time frame as the economic life of a mine. This means that new terrestrial deposits coming on line must consider the potential competition of deep sea deposits. The price of cobalt will, over the long term, be dictated by this huge supply which will progressively loom over the market. Deep-sea minerals will begin to be considered for their stabilizing role in international cobalt prices until such time as they are actually produced.
 
OST-9A: Marine Minerals Development
POTENTIAL OF MARINE VOLCANOGENIC MASSIVE SULFIDES IN THE IZU-OGASAWARA ARC, NORTHWESTERN PACIFIC
Kokichi Iizasa
 
Institute for Marine Resources and Environment Geological Survey of Japan, AIST Tsukuba, Ibaraki, JAPAN
k.iizasa@aist.go.jp
 
The lzu-Ogasawara arc located at the eastern margin of the Philippine Sea Plate is an area of potential marine mineral resources of sulfides and has characteristic bathymetry, from east to west, such as forearc basin, a volcanic front, backarc rifts, and remnant ridges.
 
Research works done by many organizations using vessels and manned submersibles in the arc brought new findings of volcanogenic massive sulfides (VMS) since the middle 1980s. A large VMS named the Sunrise deposit was discovered in a submarine caldera along the volcanic front. An active venting area was also reported in a seamount along the front.
 
The area study now focuses on an evaluation of potential mineral resources in the Sunrise deposit and other areas in the arc using a benthic multicoring system/boring machine system (BMS) operated by Metal Mining Agency of Japan, and also on the exploration of potential areas of sulfide deposits. Kuroko-type and porphyry copper type deposit have so far been found along the volcanic front and in the backarc regions.
 
Potential VMS are likely to be confined near the area of ridge-ridge intersections, caldera structures or backarc rifts in the arc. Here the distribution, modes of occurrence and potential areas of VMS evidenced by BMS samples and sulfide particles in sediments recovered are presented.
 
OST-9A: Marine Minerals Development
DEVELOPMENT OF OFF-LINE DEEP-TOW SEISMIC PROFILING SYSTEM
Kiyokazu Nishimura, Fumitoshi Murakami, Takumi Tsujino, Kiyoyuki Kishimoto and Shin'ichi Kuramoto
 
Institute for Marine Resource & Environment, Geological Survey of Japan, AIST Tsukuba, JAPAN
kiyo-nishimura@aist.go.jp
 
We have developed a deep-tow seismic profiling system. The aim of the system is to obtain high-resolution sub-bottom profiles in deep-sea. The system consists of multiple units, i.e., a deep-tow seismic profiler unit designed for low frequency sources (an air gun, a GI gun, etc.), a deep-tow sub-bottom profiler unit with a high frequency source and a unique acoustic positioning unit with depth and altitude sensors. These units are installed in a deep-tow frame. The low-frequency deep-tow seismic profiler is a single-channel digital seismic profiler with data storage, and the system is usually operated combined with the surface-tow system. We call this a hybrid survey because the system configuration is a combination of a surface-towed source (with a surface-towed streamer, most of the time) and a deep-towed hydrophone streamer. The high frequency profiler is a chirp sonar system which transmits FM sweep waves of 2-16kHz (chirp) as a source signal. This system is composed of (1) a deep-tow profiling unit with data storage, (2) a transducer, hydrophones, (3) lead-acid batteries provided with pressure compensation, and (4) an on-board data processing and display unit. Since both profilers work off-line, it has a significant operational advantage, i.e., an ordinary wire can be used for towing instead of a coaxial transmission cable. The field experiments using the deep-tow system were carried out in shallow sea and deep sea. Preliminary results will be presented to discuss and evaluate the system.
 
OST-9A: Marine Minerals Development
ENVIRONMENTAL MONITORING IN ABYSSAL LAYERS OF THE OCEANS - IMPORTANCE OF HYDRODYNAMIC STUDIES
Tatiana Demidova
 
P. P. Shirshov Institute of Oceanology Moscow, RUSSIA
tademidova@yahoo.com
 
Evaluation and prediction of hydrodynamic conditions in the entire water column, including near-bottom and upper layers, is considered to be an important element in environmental monitoring in the abyssal regions in connection with human interference, especially in the regions of the planned deep-water mining in the Pacific and Indian Ocean. Transport and re-deposition of disturbed bottom material in the bottom layer and proposed discharged material in the intermediate and upper layers, will which lead to changing chemical and physical water properties and influencing living organisms, are controlled by current speed and direction, its variability and vertical mixing.
 
Along with long-term statistical evaluations of current velocity (experimental moored data) and distribution of hydrological parameters (cast data), evaluation of meso-scale variability (of synoptic and subinertial scales, including inertial variability, barotropic and internal tides) and its long-term trends are shown to be important in understanding of environmental change fluctuations in the regions. At intermediate depths, particularly, intensive development of internal tides in the layer of seasonal thermocline might be one of the important factors of changing in water properties.
 
Evolution of kinetic energies in the water column, beginning from near-bottom levels to the surface, presents evidence of close associating between synoptic activity on the surface and high level of synoptic variability in the bottom layer.
 
Detail topographic mapping of the bottom in the region is also necessary in hydrodynamic near-bottom studies (as a component of the environmental monitoring) as topographic control of near-bottom velocity fields remains the leading factor in evaluation of hydrodynamic conditions there.
 
OST-9A: Marine Minerals Development.
EXPLORING DEEP-SEA MINERAL RESOURCES BY BMS (BENTHIC MULTICORING SYSTEM)
Katsutoki Matsumoto1, Nadao Saito1, Nobuyuki Murayama1, Masatsugu Okazaki1 and Nobuyuki Masuda2
 
1Deep Ocean Resources Development Co., Ltd. Tokyo JAPAN
Okazaki@dord.co.jp
 
2Metal Mining Agency of Japan Tokyo, JAPAN
 
Since late 1970s, the Metal Mining Agency of Japan (MMAJ) and the Deep Ocean Resources Development Co., Ltd. (DORD) have been engaged in exploring deep-sea mineral resources, such as manganese nodule, cobalt-rich crust and hydrothermal mineralization. Through these projects in which samplings were conducted mainly by dredge, large corer and power grab, it was realized that obtaining vertical core samples was essential for the evaluation of cobalt-rich crust and hydrothermal mineralization. After studying and designing of the core sampling system to match the requirements in late 1980s, the BMS was built in 1996.
 
The BMS uses standard coring tools, such as core barrel, bits and drill rod and has a capability of recovering hard rock core samples with a diameter of 44 millimeters to a depth of 20 meters. The BMS, controlled by the vehicle computer on the ship through electro-optical-umbilical cable, is equipped with an extensive suite of sensors and five video cameras.
 
It was 1998 when BMS was actually used in the project for the first time and since then useful geological information has been obtained. In this paper, advantages of the BMS in the mineral exploration are shown using some of the recent examples.







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