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By J. Robert Woolsey

The Marine Minerals Technology Center (MMTC) was established by Congress in FY 1988 as part of the Mineral Institutes Program, administered by the U.S. Bureau of Mines under the auspices of the Department of the Interior. The primary objective of the MMTC is to encourage the development of selected mineral materials from U.S. seabeds by providing opportunities for appropriate engineering systems research, development, and technology transfer within academic, government, and industrial communities. The center will also provide the leadership and facilities required for the education and training of the nation's scientists and engineers in the field of ocean mineral development. Because of the broad spectrum of study encompassed by the field of ocean mining and mineral resources, the MMTC is organized to include separate divisions for nearshore and deep ocean research. The Continental Shelf Division is administered by The Mississippi Mineral Resources Institute (MMRI) of the School of Engineering at The university of Mississippi. Operational activities will be based at the John C. Stennis Space Center near Bay St. Louis, Mississippi and the Gulf Coast Research Laboratory, Ocean Springs,

Jan 1, 1988

By John W. Padan

What is known about manganese nodules and their potential commercial recovery is outlined in terms of economics, legal rights, environmental impacts, and mineral genesis. As a result of 20 years of accomplishments it is clear that nodules comprise a real resource, and that they can be collected in water depths up to 5000 m, for brief periods, and raised to a surface vessel at rates of production appropriate for scale model systems. Based upon information in the public domain at present there is more confidence in the nature and magnitude of the resource than in the ability to recover nodules commercially. A review of the literature suggests that the metallurgical processing of manganese nodules is technically feasible and that the associated costs are well predictable. What is less clear is the market outlook for the products. All "overlapping claim" conflicts have been resolved. Therefore, parties with a historic interest in nodule mining appear now to have the right to mine in the future, assuming they properly complete whatever exploration license obligations they may have.

Jan 1, 1989

By Paul C. Rusanowski

Mining is a waste intensive industry, oftentimes producing hundreds of kilograms of waste rock and tailings for every gram of metal recovered. Disposal of mine tailings is a major concern in most mining operations. In Southeast Alaska the steep terrain and high seismic hazard province limits cost effective opportunities for land disposal of tailings. The lack of infrastructure and long travel distances generally limits secondary utilization of tailings, as well. Since the mines are located close to tidewater, submarine tailings disposal is an attractive option for tailings management. At the present time the EPA will not issue a permit that authorized marine tailings disposal from any mining process that includes flotation technology. Upland disposal is the "Best available technology" and must be used. Consideration of submarine disposal is generally precluded because the tailings are contaminated with fluids from the flotation process. However, when developing technological solutions to minimize environmental disturbance, destruction, pollution, and risk, submarine tailings disposal deserves another evaluation. In Southeast Alaska it may be the "Best available technology" based on an assessment of all issues and concerns in these mining projects.

Jan 1, 1991

By Tetsuo Yamazaki

The importance of cobalt-rich manganese crusts on the Pacific seamounts for possible future rare metal sources has currently been recognized. The thin layer-type deposit characteristics affect not only the excavation efficiency but also the economy of mining venture. Considering the thin layer-type distribution and the utilization of some rare metals in cobalt-rich manganese crusts, a preliminary economic feasibility of the mining venture is evaluated. Under some preliminary technical assumptions, the possibility of cobalt-rich manganese crusts for future rare metal sources for Japan is examined. The important role of utilization of rare metals in the crusts is highlighted.

Jan 1, 2010

By Lu Jun

Up to now, much data on marine minerals, as well as on marine geochemistry, have been accumulated. Modem computer databases provide optimum flexibility and power for manipulating these data. The best worldwide marine mineral database is currently the Marine Minerals Bibliography and Geochemical Data Base created by Carla Moore et al. at the National Geophysical Data Center in the United States. In fact, in the course of studying marine minerals and geochemistry we may collect not only digital-character type data but also graph and image (black-white, grey and color image) data types. For instance, correlation diagram between chemical compositions of minerals, spectroscopic graphs, (e.g. infrared spectra, Mossbauer spectra, etc.), grey or color images from both optical and electron micro- scopes (scanning or transmission electron microscopes) as well as seabed photographs. Charles L. Morgan et al. (1993) reported that 10,000 photographs and some video images of the seabed in the Clarion-Clipperton region of the northeastern tropical Pacific have been collected by the Ocean Minerals Company. If both graphic and analytical information were stored in a database, it would be very useful and convenient to marine geologists. This system would not only be able to search for all the data based on one parameter, but also for both size and composition distributions. If possible, geostatistical methods could be combined with fractal dimensional methods. Of course, this would require enormous efforts. Before multimedia technology emerged, it was very difficult to create image databases. The emergence of large-capacity compact discs, high-speed central processing units, and high-speed digital signal processing techniques makes it possible to establish multimedia database management systems (DBMS), image-text DBMS, that involves graphs, text, images, and sound. In order to store image fields in a DBMS, we have to take into account two problems: (1) image access format and (2) image compression code standard.

Jan 1, 1994

By Richard T. Haworfh

The United Nations Convention on the Law of the Sea (UNCLOS) entered into force, for those nations who had ratified it, on November 16, 1994. The Convention deals with nearly every aspect of ocean affairs, including marine scientific research, fishing zones, freedom of the high seas, protection of the marine environment and deep seabed mining. Article 76 of the Convention defines edge of the continental shelf in a way that many earth scientists find bizarre. Out to this limit, a coastal state has sovereignty over the seabed and sub-seafloor resources. Beyond that limit, the key principle of UNCLOS, that "the resources of the deep seabed represent the common heritage of mankind and should be developed to benefit all nations" is invoked. Establishing that limit and managing development in the different areas of jurisdiction is no small task. Canada's continental shelf as defined by UNCLOS covers an area approximately equal to half the area of the Canadian land mass. Interpretation and application of the convention is therefore highly significant for Canada. For example, the sedimentary basin in which the offshore Hibernia oil field is found, extends beyond the 200 mile limit but lies predominantly within the limits of the (UNCLOS) continental shelf. Responsibility for development of inshore placer deposits rests firmly with the coastal state. However, development of deep sea mining, in which the international community plays a management role under UNCLOS, has raised many concerns. Of particular interest to Canada will be the application of the provisions of the convention to interest in the polymetallic sulfides sampled on the mid-ocean ridges such as the Juan da Fuca Ridge. A further complicating factor for Canada is management of fishing stocks. Canada has sought to resolve this "problem" through multilateral negotiations under the UN. Under its "Oceans Act," currently being debated by Parliament, Canada intends to become a world leader in oceans and marine resource management. Similar activity in most maritime nations is setting the stage for a revolution in the way in which use of the world's oceans is managed. Much of this revolution will be guided by UNCLOS. Coastal states that have ratified the convention have ten years in which to define the limits of their continental shelves the clock is already ticking for them! We have yet to see how their actions will guide, or be guided by, those who have not yet ratified. We also have yet to see how national legislation and aspirations will mesh with international conventions that were drawn up in a previous era of environmental standards. This is a time in which many questions have been raised and few firm answers received. However, we must ensure that everyone is aware of what is happening, with what potential consequences, in order that rational decisions can be made. Canada has taken a few small steps that it is happy to share with the world community.

Jan 1, 1996

By S. Jeffress Williams

The topic area for this paper covers the United States portion of the northern Gulf of Mexico, extending from the Rio Grande delta east to the Florida peninsula. Declaration of an Exclusive Economic Zone in 1983 expanded Federal economic jurisdiction on the continental margins from 12 to 200 nautical miles seaward from the coast. The nation-wide area of the EEZ totals 3 million square nautical miles, with approximately 186 thousand square nautical miles in the Gulf of Mexico. In the Gulf, the continental shelf has an area of 81 thousand square nautical miles, extending to a depth of 600 ft. and having widths of 6 to 120 nautical miles. Specific areas on the shelf offer the greatest potential for containing aggregate and other hard mineral resources. The primary geomorphic features along the Gulf coast include: barrier islands, chenier plains, tidal inlets, bays and lagoons, estuaries, and deltaic headlands. These features are composed of terrigenous siliclastic sediments, except for the west Florida coast, south of 29°N latitude, which is dominated by carbonate sediments. On the shelf, the primary features are linear sand shoals and associated sand sheets, relict delta lobes and channels, and banks related to salt diapirs and coral reefs. The composition and distribution of sediments in these coastal and shelf features are determined by numerous geologic factors including: seabed topography; riverine sediment discharge; sediment dispersal patterns due to currents, waves, storms and tides; tectonics and subsidence; and repeated fluctuations in sea level.

Jan 1, 1986

By C. R. Pearce, B. Murton, S. Howarth, P. Lusty

"With the expansion of “green” energy technologies, the demand for the critical raw materials required to sustain this growth is increasing. Many E-tech elements, including tellurium (Te) and rare earth elements (REEs), suffer from high supply shortage risk and the need for more diversified metal supply routes is driving research into alternative resources. Hydrogenetic ferromanganese crusts, seafloor deposits of Fe- and Mnoxyhydroxides that form from the direct precipitation from seawater, present a potentially important future source of E-tech elements. With growing interest in the potential wealth of these deposits and the issuing of permits for deep-sea mining and exploration, more work is underway to understand the nature of ferromanganese crust deposits, their elemental concentrations and distributions, and the potential impacts of mining activities.This research focusses on the formation of ferromanganese crust deposits and processes that control the extreme enrichment of elements such as Te, Co and REEs. The crusts were systematically sampled and mapped between ~ 1000 – 4000 m depths using ROV ISIS, from a range of environments, substrates and morphologies from Tropic Seamount (NE Atlantic) in order to determine the seamount-scale factors that control major and trace elemental concentration variations. These factors include depth, surface roughness and micro-bathymetry, location relative to long-term mean current direction and energy, influence of tidal energy dispersion across the seamount, sediment supply, substrate lithology, biological productivity and phosphatisation. The study analyses trace-element characteristics of 100 ferromanganese crust samples alongside standard reference materials NOD-A-1 and NOD-P-1 (US Geological Survey manganese nodules). At this initial stage, we report results from whole rock acid digestion and ICP-MS analyses."

Jan 1, 2017

By Roger J. Daniel

Major interest and investment in southern Africa's west coast diamond deposits have resulted in the development of various tools for sampling and mining in the varied geological conditions encountered. Namco's project progression from sampling to mining is discussed with particular reference to the ROV technology employed for both phases of the operation. The Namrod sampling tool was mobilised in June 1995 and following extensive sampling resulting in resource definition, detailed research, design, and engineering was undertaken to develop the NamSSol mining system in conjunction with SubSea Offshore Ltd., a Dresser Industries company. Mining operations commenced in early 1998. History of the background to the development leading to design criteria, engineering considerations, operational parameters and discussion of field performance are presented. The innovative systems employed by Namco represent significant developments in a rapidly expanding technological field.

Jan 1, 1998

By Nobuyuki Okamoto, Bhaskar Rao

For a period of twenty years - from 1985 to 2005 - the Japan Oil, Gas and Metals National Corporation (JOGMEC) and Pacific Islands Applied Geoscience Commission (SOPAC) have jointly conducted surveys of deep-sea mineral resources in the EEZs of SOPAC’s twelve member countries. The overall Programme has obtained excellent results and has identified numerous sites with potential marine mineral resources of manganese nodules, cobalt-rich manganese crusts, and polymetalic massive sulphides. The survey cruises have identified numerous sites with potential marine mineral resources such as: manganese nodules in the Cook Islands; cobaltrich manganese crusts in the Marshall Islands, FSM, and Kiribati; and polymetalic massive sulphides in Fiji. Based on collected samples and acoustic data, inferred resources for manganese nodule, cobalt-rich manganese crusts, and polymetalic massive sulphides, have all been estimated to be about- 200 million tons in the central Cook waters- 200 million tons in the three seamount selected Marshall waters- and 500 thousands tons around the triple junction of the North Fiji Basin.

Oct 15, 2007

By William C. Hirt

Column flotation is a promising technique for processing as-mined, cobalt-rich, ferromanganese crust to separate the valuable crust component from barren substrate-rock, either aboard ship or within the water column. Column flotation testing was carried out in a seawater medium using samples obtained from the U.S. Exclusive Economic Zone (EEZ) in the mid-Pacific Ocean near Johnston Atoll. The collector reagent was a mixture of diesel fuel, fatty acid, and sulfonate previously developed at the U.S. Bureau of Mines for crust flotation using conventional flotation cells. Results are dependent upon particle size and reagent dosage, especially *as these factors affect froth volume and stability. Column flotation results are compared with previous studies in conventional cells. An overview of how column flotation might be applied in an offshore mining and processing system is given.

Jan 1, 1992

By S. Rajendran

The western continental margin comprises of the southwest coast (Cape Comorin-Mangalore), centralwest coast or Konkan coast (Mangalore-Bombay), northwest coast (Bombay-Gulf of Kutch) and the Laccadives area. Placer deposits of heavy minerals occur in discontinuous patches on the beaches along many parts of the west coast. The richest offshore placer deposits occur along the 25 km stretch of the southwest coast from Neendakara to Kayamkulam. The National Institute of Oceanography (NIO) surveys show that the sediments off the Konkan coast consist largely of silty sand, sandy silt and clay and the concentration of ilmenite is higher than the onshore. The heavy mineral concentration ranges up to 90% and has mainly ilmenite and magnetite with minor quantities of apatite, rutile, zircon, kyanite etc. The heavy mineral sands extend below the clays to water depth down to 20 m. The heavy minerals sands vary in thickness from 2-10 m. Offshore placers can be mined by using wire-line, bucket ladder and hydraulic dredges. Wire-line, bucket ladder and hydraulic dredges. Wire-line dredges may employ drag buckets or clamshell and hydraulic dredges suction or airlift principles. The dredges can be located on flat bottom or catamaran barges. Dredging of very near shore placers may be achieved by operating from land. The bucket ladder type of dredger has greater digging ability and hence can be deployed for mining placers which are partly consolidated or cemented or where the most valuable part of the deposit lies at the contact between the alluvium and the bedrock. This type operates very economically up to 45 m depth and needs minimum power requirement per unit dredged. Suction type hydraulic dredges can be operated very effectively up to 60 m water depths. This system is quite ideal for the inner shelf. The maximum practical economic working water depths for wire-line dredges are about 150 m. With the drag bucket modified into large net buckets, the method can be utilized to greater depths. They can be used in areas of high water currents and swells. The type of bucket can be changed readily with change in the nature of alluvium or substratum. The hydraulic suction dredge is the most suitable system for mining unconsolidated sediments. When the sediments are semi-unconsolidated, a cutter head can be mounted on the lower end of the suction pipe to agitate the seabed.

Jan 1, 1996

By Patrick J. C. Ryall

Remotely control led drills capable of being lowered to the sea-floor from ordinary research vessels have been developed over the past two decades. These drills are currently being used in geological survey programmes on the continental shelves (Canada, Japan, Norway, United Kingdom) and for studies of mid-ocean ridges. Generally the drills fall into two categories: 1) those which are powered from the surface and controlled by an operator, and 2) those which are battery powered and follow an automatic programme. Some drills have a television camera mounted on them sending a picture to the surface as an aid to site selection and geological interpretation. Typically the drills are capable of drilling a core 2.5 - 5 cm diameter up to 10 m long. While most of these drills are designed for <1000 m depth, some can drill in water depths of as much as 3500 m.

Jan 1, 1985

By Robert G. Ditchburn, Cornel E. J. de Ronde, Bernard J. Barry

The age of mineralization, its mode of formation, the time elapsed to amass an economic deposit, its capacity for sustainable extraction and, ultimately, its grade and tonnage, are key aspects in the economic viability of volcanic massive sulphide (VMS) deposits (Ditchburn et al, 2004). Radiometric dating methods applied at GNS Science have been recently refined with the purpose of efficiently determining the ages of seafloor VMS mineralization along active intraoceanic arcs. These developments include: determining the longevity of seafloor hydrothermal systems, details of individual chimney and massive sulfide mound growth, and insights into deep-seated processes, such as the transfer of elements from magmas to their overlying hydrothermal systems. In our pursuit to better understand seafloor hydrothermal systems along intraoceanic arcs, we have thus far compiled age information for three volcanic centres of the Kermadec arc (South Pacific) and one of the Mariana arc (NW Pacific).

By Andrew E. Grosz

The United States is dependent on foreign imports for about 80 percent of its ilmenite, about 60 percent of its rutile, and virtually all of its monazite. Nearshore marine sand deposits and beach-complex sediments in the southeastern United States are important domestic sources of ilmenite, leucoxene, rutile, zircon, monazite, and a number of other less well known economic heavy-mineral (HM) species. Because global onshore reserves of placer titanium minerals may fall short of demand in as few as 20 years, offshore research in HM placers will become more important. The Atlantic Continental Shelf (ACS) defined by the shoreline and the 200-m isobath varies in width for the modern U.S. coastline from a fraction of a kilometer to about 150 km offshore of Cape Cod, Mass., and includes an area of about 3.91 x 105 km2. It probably contains 3-7 x 1011 m3 of sand and gravel which may locally contain commercially exploitable placer HM deposits.

Jan 1, 1986

By S. Rajendran

Much advance has been made in offshore hydrocarbon exploration and exploitation in India. But the same amount of success could not be achieved in the case of other offshore minerals which are amenable for mining. However, employing present technology, there should not be any difficulty in successful exploitation with minimum environmental hazards. A demonstration is provided by considering the conditions prevailing in the Kerala offshore (southwest coast of India) scenario of monazite, ilmenite, phosphatic mud and calcareous deposits. Mud banks are unique phenomenon of the Kerala coast during monsoon season. Acting as barriers to waves, mud banks protect portions of the beaches from being eroded and trap sediments from either side facilitating growth of adjacent beach. The easy minable possibilities of the phosphatic mud during non-monsoon season with less pollution hazards and dumping back the waste material after processing for phosphate at the breaker zones to reduce the erosional effects on the coast make the exploitation economic and ecofriendly unlike the benefication of the lowgrade phosphate ores on land on a comparatively larger area and subsequent crushing, transport and resulting pollution.

Jan 1, 1993

By P. U. W. Appel

Despite the very large offshore Exclusive Economic Zone (EEZ) area of Greenland (in excess of 2 mill. km2) virtually no work has been carried out on marine minerals on the ocean floor. Apart from a single reconnaissance survey by a mining company, major activities have been those of oil companies exploring the West Greenland shelf in the early seventies. The West Greenland shelf and its extensions is the most obvious area for year-around accessability when looking for marine mineral deposits. So far, only one onshore placer deposit has been found - ilmenite deposit near Thule, NW Greenland, whereas a gold placer in South Greenland presently is being evaluated.

Jan 1, 1988

By Tap Pryor

A very small nation with large seabed resources requires a strategy. The simplest approach is to duplicate every step taken by the United Nations (UN), in its own leasing programme. In addition, the smaller nations must sell itself and its competitive offering. It is one thing just to await applicants and/ or tenders, another to work to make the leasing seem like a very good idea. This cap be achieved through publications, correspondence, meetings (such as the Underwater Mining Institute, but especially through pro-active planning, seeking the ideal technologies in both harvesting and processing. The ideal would be some combination that could begin quickly and on a small scale. It must be within the UN environmental guidelines. To meet the "quick and small criteria," simple harvesting and physical processing methods must be given the highest priority. Once these are satisfied, then marketing studies can be completed. There is, of course, a market for every element but only careful engineering and cost analysis will determine accessibility. What is required is a stepwise approach, gaining greater and greater credibility at each step. In fact, much planning can be done for very low cost. In the Cook Islands, the first crucial step was the East-West Center publication which pulled together all facts in one volume and which found the local resource to be richer in significant ways than Clarion-Clipperton. Most seem to believe that it could be many years before full production is possible, but this has been conventional wisdom for so long that it has taken on the suspicious aura of myth. Is it real? Have all possible recent technologies such as robotics and physical processing been taken into account? Either way, it is essential that a comprehensive approach be taken so that all factors from resource to market are considered as inter-related until a single business plan emerges. When that is in hand and when its profitability and risk levels are found to be credible, adequate investment funds are available.

Jan 1, 1994

By Peter B. Hale

Canada has a long history of marine-related industry and onshore mining. Even so, commercial interest in marine mining, excluding seawater mineral extraction and offshore extensions of hardrock deposits such as iron and coal, has been sporadic; despite the fact that shelf mineral deposits supply a significant proportion of the national market requirements for many countries. Several factors have accounted for this including: a relative abundance of onland mineral desposits; the fact that onland deposits can be mined using conventional technology; and, a general lack of knowledge and public awareness as to Canadian offshore non-fuel mineral resource potential. In the mid-1970s the Department of Energy, Mines & Resources formed the Departmental Coordinating Committee on Ocean Mining. The Committee addressed the question of shelf non-fuel mineral resource potential and concluded that, while several reports had raised the possibilty of this alternative source, there had not been a systematic evaluation of the resource base. This led to the formation of a Shelf Working Group, whose task it was to outline and implement a departmental program to advance our knowledge of shelf resource potential. A methodology was devised that utilized existing geoscientific and hydrographic

Jan 1, 1985

By Ian Selby

Recent offshore diamond exploration has been concentrated in the SW Joseph Bonaparte Gulf. I`IW Australia. Extensive high resolution seismic and sampling surveys have been carried out in Cambridge Gulf, offshore of the mouth of the OR River and other rivers of the region. Surface-tow boomer surveys have been correlated with sampling data from vibracores and a wide diameter (1m) airlift system, providing a geological framework for the area. Although large-scale bulk sampling has not been undertaken, there has been no reported recovery of diamonds since 1993. The geology and prospectivity of a range of potential diamond traps in high energy, fluvial and transgressive depositional settings has been assessed. Potentially diamondiferous targets include (i) a shoreline apron. (ii) fluvial/estuarine channel infills and terraces and (iii) ravinement surfaces.. Although there is evidence for a long history of fluvial development and sea level changes, the majority of the investigated traps represent the result of erosion and sedimentation during and following the last interglacial. Significant volumes of unconsolidated gravels and coarse-grained sands with occasional indurated layers are present, and are locally exposed at sea beet In place s thick successions (>5m) of fine-grained overburden overlie the coarse-grained sediments.

Jan 1, 1998