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By Wilhelm Schwarz

Manganese nodules lay in vast areas of the deep sea floor. Ideal harvesting conditions for a manganese nodule field are dense nodule abundances of nodules between 20 and 60 mm diameter and a metal content as high as possible. With regard to the development of collector technology, the properties of the deep sea soil, in which the nodules are embedded and to which the nodules stick, are of major interest. The forces for loosening the nodules have to be provided by the collector. For this purpose water jets and/or mechanical devices can be employed. For the choice of the best collecting procedure, various criteria, such as collecting rate, energy consumption and the environmental impact on the eco system of the deep sea floor, have to be considered and weighted as to their importance. Nowadays, the concept of a mining system with a flexible transport hose and a self propelled collecting machine is increasingly accepted among the expert community. With regard to the trafficability of the deep sea soil with a self propelled mining machine, the mechanic properties of the soil and the morphology of the deep sea floor are of special importance. The manganese nodule fields, which are interesting with regard to their recoverability, are mostly in the areas of tectonic fracture zones, at which the morphology of the sea floor is formed by vulcanic activities. In these areas, deep sea mountains, pits and other obstacles exist that have to be driven around if not trafficable.

Jan 1, 2003

By William D. Siapno

Mining the deep ocean by the year 2000 may seem far fetched. The year 2000 is but a decade away, a scant 10 years. Remember, the youngsters of today will grow up in a little more than a decade and rebut the wisdom of the ages, especially the traditions of their elders. Rude perhaps, but none the less a fact of life. Ocean mining exhibits many of these same traits. We should all brace ourselves for some rude shifts in our rapidly moving society. Major shifts in economics, politics, and social orders are the rule of the day. Communism is in retreat, our own economic structures chaotic. So in this moment of cataclysmic change, a shift in the international market place of mineral resources should not be a great surprise.

Jan 1, 2011

By William D. Siapno

Approximately a century lapsed between the time nodules were discovered and the beginning of commercial exploration in the early 1960's. A period of rapid development of exploration and mining technology ensued over most of the next two decades. In recent years advancement has been sharply curtailed. This paper discusses the constraints inhibiting nodule mining and some developments that could aid in overcoming certain difficulties. Specifically, the greatest single constraint is economic. With few exceptions mineral markets are badly depressed. Present projections for development of nodules are for the late 1990's or beyond. However, the U.S. awarded exploration licenses in mid-1984 and more recently boundaries of license areas have been released. These conditions promote cooperation among organizations engaged in deep ocean mining. Survey data, and where appropriate some data products, have been exchanged between various consortia. The present hiatus in at-sea activities provides an excellent opportunity to investigate the best means to proceed. This period of quiescence offers a rare moment to distill the meaningful values of an era of hectic activity to permit more efficient development in the future.

Jan 1, 1985

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 Graham Singleton

Around 235 million tonnes of marine aggregates have been dredged in the last decade from the UK continental shelf alone. The current distribution of marine aggregate production licence areas in North West Europe reflects the relationship between a variety of factors such as the natural distribution of deposits of sand and gravel, the demand for aggregates, the technical capabilities of the dredging fleet and environmental considerations. Whilst the sand and gravel deposits targeted by the marine aggregate industry are generally relict and therefore geographically fixed, the remaining factors have evolved over time and will continue to do so in future. Applications for new licences must not only reflect the current situation, but anticipate future trends. The main markets for marine aggregates are the construction industry, centred around the larger centres of population and coastal protection projects along the coastline of Europe. The aggregate industry as a whole does not create demand but simply meets it. Many factors influence the overall demand for aggregates and guidance exists for those in authority and industry who need to plan for the supply of aggregates. Adequate supplies should be maintained at the best balance of social, environmental and economic cost, whilst ensuring that extraction and development are consistent with the principles of sustainable development.

Jan 1, 2004

By David G. Jones

Radiometric surveys of the beach and nearshore zone of the Dutch Frisian Islands have identified sands enriched in heavy minerals. The areas of heavy mineral concentration have been mapped in detail using a state of the art towed gamma-ray detector, which gives improved sensitivity through the use of new detector materials and improved data processing techniques. The detector provides continuous measurement of sea floor radioactivity (and of a number of other parameters) and can be used simultaneously with other survey techniques, such as echo sounding, sidescan sonar and shallow seismic profiling. It enables a rapid, and cost effective, assessment of the surface distribution of heavy minerals to be made. The heavy mineral suite includes magnetite, ilmenite, garnet, rutile and zircon. These minerals contain 1-3 orders of magnitude more U and Th, in terms of their activity concentrations, than the accompanying light minerals (mainly quartz). Since the heavy mineral composition of the sands appears to be relatively constant along the Dutch Frisian Island chain, the U and Th concentrations can be used to provide a quick estimate of the heavy mineral content. The sea floor radiometric measurements allow sediment sampling for more detailed analysis to be highly targetted. The zones of heavy mineral enrichment are generally sub-parallel to the coast and are usually confined to water depths of 5-10 m. There is a close correlation with sand bars on the shoreface, the highest radioactivity typically occurring just seaward of the crest of these features. As well as being used for heavy mineral exploration, similar radiometric methods can be applied to mineral processing. Gamma-ray detection systems can be used to provide rapid analysis in the process stream enabling on-line grade control and optimisation of processing, from excavation of mineral sands to the final products.

Jan 1, 1995

By Richard H. T. Garnett

On the western continental shelf of southern Africa diamonds derived from onshore sources are concentrated in gravels within drowned terrestrial and marine geomorphological features. First discovered offshore in the late 1950's, they are known to exist for about 1400 km along the Namibian and South African coast in water depths of up to 200 m. Shallow water operations yielded 1.5 Mct during the decade ending 1970 when De Beers acquired a majority of the offshore leases and commenced a 15 year exploration program. Deeper water and the prevailing sea conditions required the development of new, unique, marine mining equipment. The first large scale mining production of 22 kct was achieved by De Beers in 1989 with an output of 22 kct. Annual marine output from all sources now exceeds 0.6 Mct worth some US.$ 170 M, and rising to 0.7-0.8 Mct for 1998. Exploration has also been taking place in the waters of West Africa, Australia, and Indonesia. Exploration is by means of high resolution geophysics followed by sampling using a variety of drills, airlifts and seabed-mounted machines which imitate the eventual mining process. Surveying is now probing depths of 500 m. Smaller scale mining by several junior companies has traditionally involved diving and airlift systems. Increasingly, however, they are adopting different and improved techniques which to date have been employed only by De Beers Marine as contractor to Namdeb. Marine exploration and unit mining costs are high compared to those applicable to alluvial deposits onshore. By 1996 the total development costs incurred by De Beers alone reportedly had exceeded US.$ 500 M. However, the financial rewards are commen-surate because of the higher recovered grades. The operations are not without risk for the total of nearly 10 large and medium scale production vessels deployed by various organisations. The greatest shortfalls are experienced in the estimated throughput, not the grade.

Jan 1, 1998

By G. Rehder, C. Hensen, P. Linke, J. Bialas, M. Haeckel, W. Weinrebe, K. Wallmann

Research on marine gas hydrate and the methane cycle has a tradition at IFM-GEOMAR. In summer 1996 during a cruise with RV SONNE offshore Oregon (USA) scientists of the former GEOMAR recovered the largest amount of gas hydrate from the seafloor. This discovery stimulated research on marine gas hydrates in Germany and induced funding of scientific programs such as LOTUS and OMEGA with numerous innovative technologies within the special program GEOTECHNOLOGIEN of BMBF and DFG. The primary objectives of ongoing and future research are to achieve a comprehensive knowledge of: • gas hydrate distribution and quantity; • variation and regulation of gas hydrate formation and dissociation as well as of the related fluid flow; • functioning of chemosynthetic communities in methane oxidation, carbonate precipitation and methanotrophy as biological barrier against methane emission and • delineating the escape routes of methane to the hydrosphere and atmosphere.

Aug 24, 2006

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 Carl H. Hobbs

The marine mineral resources of the U.S. middle and south Atlantic shelf are little utilized. The largest resource, sand and gravel, is used for beach nourishment and protection and, to a much lesser degree, as construction aggregate. The potential for increased utilization is great. Submarine deposits of shell have been mined for lime and for use in the oyster industry. Although significant quantities of manganese nodules and crusts are present on the Blake Plateau, exploitation in the foreseeable future is unlikely. Similarly, major phosphorite deposits in North Carolina's inner shelf probably will remain unexploited as long as onshore deposits remain available. Placer deposits of heavy-mineral sands, especially the titanium minerals, offer the possibility of exploitation. This possibility might be enhanced by consideration of joint development of sand or aggregate with heavy minerals.

Jan 1, 1992

By Lee Sung-rock

KIGAM (Korea Institute of Geoscience and Mineral Resources) has been doing various kinds of research works in marine minerals and energy resources exploration and utilization since early 1990s in Korea. In the presentation, the authors will introduce the recent research and development activities mainly focusing on the rare earth metals of the Pacific deep seabed Mn-nodules and gas hydrates which occur from Korean deep waters. KIGAM has been participating in the polymetallic manganese nodule exploration, mining and metal-extraction project, which is modulated by KIOST (Korea Institute of Ocean Sciences and Technology, formerly KORDI). Now KIGAM puts more focus on extracting precious and rare earth metals from the Mn-nodule as well as underlying sediments. The rare earth elements (REE) from seabed mineral deposits also draw attention to those countries including Korea which are lack in natural resources. KIGAM is doing several kinds of leaching experiments using various kinds of reagents under the different experimental parameters. Extraction of rare earth metals from deep sea nodule using H2SO4 and HCl solution showed good leaching effect. As the gas hydrates are to be evaluated as a new future energy resource globally, Korean government has initiated national R/D program covering fundamental exploration survey for resources assessment in Korean deep waters and production technology development. KIGAM plays a key role in seismic exploration, resources assessment, experimental

Sep 14, 2011

By Robert M. Owen

The reconstruction of ocean history has been a major focus of marine research over the past decade. A significant outcome of these investigations is the recognition that certain types of marine mineral deposits are linked to regional to global scale changes in ocean composition and climate conditions. Manganese-bearing deposits are of particular interest in this regard because changes in their occurrence, distribution and/or composition are responsive to both biochemical and geological factors. Analyses of such deposits whose formation spans critical age/epoch boundaries thus provide clues concerning the interplay of different process during anomalous periods in Earth history. Recent studies demonstrating this deposit - event - process relationship include: (1) Changes in the bulk chemical composition of ferromanganese crusts during the Late Miocene-Early-Pliocene (-7-3 Ma) that coincide with a period of enhanced biological productivity in the eastern equatorial Pacific upwelling zone; (2) The formation of large statiform manganese deposits at the Cenornanian- Turonian Boundary (-92 Ma) in association with widespread oceanic anoxia; and (3) Increased deposition of hydrothermal precipitates caused by tectonic reorganizations at the Paleocene - Eocene boundary (-55 Ma) that resulted in global-scale changes in atmospheric and oceanic circulation and climate.

Jan 1, 1995

By Akuila K. Tawake

The occurrences of polymetallic minerals within the Exclusive Economic Zones (EEZs) of many Pacific Island Countries (PICs) have been confirmed through marine scientific researches and seabed minerals exploration in the last forty years, and are increasingly being recognized by nations as a future potential source of revenue and economic development. For many of the smaller PICs, this may represent the only exploitable natural resource sector apart from fish. SOPAC (then under the CCOP/SOPAC) was actively involved with deep sea mineral exploration in many countries in the South Pacific between the 1970s and early 1980s that led to the discovery of a number of seabed mineral occurrences within the EEZs of these countries. In collaboration with SOPAC, a number of multinational consortia and national agencies were involved in this early stage of seabed mineral prospecting in the region. This was followed by a twenty-year (1985-2005) marine mineral prospecting in the Pacific through the collaborative effort of the Government of Japan and SOPAC as well as the Ridge 2000 program. Other mineral prospecting and marine scientific research initiatives have been conducted in recent years and the most notable one is the Nautilus Minerals advanced exploration in the Manus Basin in PNG. Based on the results of previous exploration, a number of countries in the region with moderate to high deep sea mineral resources potential are identified. Seafloor Massive Sulphide deposits have been confirmed in PNG, Tonga and Fiji while the Cook Islands and Kiribati have high manganese nodule resources potential in addition to significant occurrences of Cobalt-rich Crust within the EEZs of the Marshall Islands and the Federated States of Micronesia. Despite the recent surge in deep sea minerals interest and activity around the Pacific, specific policy, legislation and regulations necessary for the governance of deep sea mineral resources are lacking. Also lacking is the specific technical and human resources capacity essential to ensure that PICs are able to effectively manage these seabed resources. Consequently, SOPAC under the EU funded Deep-Sea Minerals (DSM) Project will work with Pacific ACP States to develop a regional regulatory framework from which they can develop their national frameworks for the sustainable management of their marine mineral resources. The work is of critical importance if PICs are to have effective environmental, fiscal and social management instruments in place for the exploration and exploitation of deep sea minerals that could support economic growth within the region as a whole.

Jan 1, 2010

By Sukumar Bandopadhyay

The Marine Mining Technology Center (MMTC) was authorized by an act of the United States Congress in 1996. The act established several marine minerals research centers in the U.S., including one at the University of Alaska Fairbanks. The Alaska MMTC is funded through the Minerals Management Service of the Department of the Interior and concentrates its research in the Artic seas region. Recent research projects at the MMTC include, among others, a geographic information system (GIS) application to the gold placer deposits offshore Nome, Alaska, a marine gold placer reserve definition model using a neural network, and development of an expert system model for submarine tailings disposal (STD) planning and decision-making. Although geostatistics remains the most prevalent method used today for ore grade estimation, researchers have made numerous improvements over the years for accurately predicting grades of ore using various other estimation techniques. As a result, the neural network has recently emerged as an alternative to geostatistics for grade estimation purposes. A neural network is a non-linear, model-free estimator that is well-suited for noisy and/or sparse data environments. Neural networks perform best with non-linear spatial data, contrary to the stationary assumption of ordinary Kriging techniques. In the marine placer ore reserve definition model, the neural network technique was used to estimate placer gold reserves offshore Nome. This study demonstrated the utility of neural network modeling over other traditional ore reserve estimation methods, especially for high cut-off grades. Some of the relevant issues of neural network modeling were also addressed in the study. In testing, the neural network produced results that were close to those from geostatistical techniques including Kriging, polygon, and inverse distance methods.

Jan 1, 2004

By Sukumar Bandopadhyay

The Marine Minerals Technology Center (MMTC) was authorized by an act of the United States Congress in 1996. The act established several marine minerals research centers in the U.S., including one at the University of Alaska Fairbanks. The Alaska MMTC is funded through the Minerals Management Service of the Department of the Interior and concentrates its research in the Arctic seas region. Recent research projects at the MMTC include, among others, application of a geographic information system (GIS) to the gold placer deposits offshore Nome, Alaska, development of a marine gold placer reserve definition model using a neural network, and development of an expert system model for submarine tailings disposal (STD) planning and decision-making. Although geostatistics remains the most prevalent method used today for ore grade estimation, researchers have made numerous improvements over the years for accurately predicting grades of ore using other estimation techniques. One such technique, the neural network, has recently emerged as an alternative to geostatistics for grade estimation purposes. A neural network is a non-linear, model-free estimator that is well-suited for noisy and/or sparse data environments. Neural networks perform best with non-linear spatial data, contrary to the stationary assumption of ordinary Kriging techniques. In the marine placer ore reserve definition model, the neural network technique was used to estimate placer gold reserves offshore Nome. This study demonstrated the utility of neural network modeling over other traditional ore reserve estimation methods, especially for high cut-off grades. Some of the relevant issues of neural network modeling were also addressed in the study. In testing, the neural network produced results that were close to those from geostatistical techniques including Kriging, polygonal, and inverse distance methods.

Jan 1, 2005

By J. Robert Moore

Introductory remarks will be made by the speaker, chiefly on recent and current developments in the industrial, agency and academic sectors that relate to the status of marine mining and mineral exploration programs and to recommendations for strengthening and continuing these programs. Subsequent to these brief comments, a selected panel with representation from industry, academe and government will address the following related topics: 1) development and objectives of new centers for marine mining technology, 2) cooperative R. and D. programs between academe and the user groups, 3) arrangements for specialized training and student instruction that will provide for educational components, and 4) funding and other support for implementing new centers and new programs. The panel discussion will be open to all UMI participants and whose contributions will be both solicited and encouraged.

Jan 1, 1986

By Charles L. Morgan

For the past twenty years or so the oceans of the world have been transformed in the minds of most Americans from the ultimate and nearly infinite receptacles for sewage and other wastes to an almost sacrosanct and threatened last refuge of Mother Nature from man on Earth. While this general movement has helped somewhat to moderate the flows of pollutants into the oceans, it has had severe and sometimes devastating impacts upon various attempts to develop seabed mineral resources. Marine mining proposals have been easy targets for attack. In most cases, they have short or no histories and involve prototype or first-generation methods. They commonly lack major financial backing, and do not command significant public support. Their constituents are limited. Opposition movements to such proposals have been able to evoke strong support by appealing to this "last refuge" image and depicting mining operations as the final assault. In mounting these public appeals, the movements obtain visibility and support. Because of the small and sometimes tentative status of the constituencies which support particular proposal s, the potential liabilities for opposition movements are minimal.

Jan 1, 1989

By Charles L. Morgan

"In 2012 the International Seabed Authority (ISA) established nine “Areas of Particular Environmental Interest” (APEIs) for consideration as future Marine Protected Areas to help preserve the biodiversity of life on the seabed within the Clarion-Clipperton Zone (CCZ) between Baja California, Mexico, and the Hawaiian Islands. The CCZ is believed to have a high potential for future seabed mining operations. Areas under active exploration contracts in the CCZ, plus the areas currently reserved by the ISA for exploration by developing nations, comprise about 1.9 million km2 of seabed area. The currently designated APEIs consist of more than 1.4 million km2 of seabed. Each APEI includes a central primary conservation area of 200 X 200 km, surrounded by 100-km buffer areas on all sides. The 100-km buffers are intended as a very conservative spacing between the primary conservation area and potential mining activities in adjacent seabed. The selection of these nine 400 X 400 km APEIs, has been criticized as possibly not including sufficient representative habitat similar enough to the potential mining areas (identified currently as the exploration contract and reserved areas administered by the ISA within the region) to ensure protection of the biodiversity that might be impacted by mining.An area to the east of the existing exploration contracts and reserved areas is known to have substantial mineral deposits; it is very similar to the adjacent exploration contract areas in its geology, environmental setting, polymetallic nodule abundance and nodule metal content. Because it is located in the northeastern extreme of the CCZ, this area is also likely to have relatively high densities of benthic life, compared with benthic communities further westward within the CCZ. Many options for the designation of this APEI are possible, but the area designation must accommodate the boundaries of the Exclusive Economic Zones of Mexico and France.This paper discusses why the selected region in the eastern extreme of the CCZ is a good candidate for designation as a new APEI.Keywords: polymetallic nodules, Marine Protected Areas, Clarion-Clipperton Zone, Areas of Particular Environmental Interest"

Jan 1, 2017

By Carla J. Moore

The National Geophysical Data Center (NGDC), Marine Geology and Geophysics Division and co-located World Data Center-A for MGG archives and distributes global marine sediment data from U.S. and international sources. NGDC is part of the U.S. Department of Commerce, National Oceanic and Atmospheric Administration (NOAA), National Environmental Satellite, Data, and Information Service. NGDC offers a variety of digital marine sediment data sets including sediment descriptions, textural analyses, geochemistry, paleontology, paleomagnetism, and well logs. Some data sets are compiled by outside sources and sent to NGDC for distribution; many are received under exchange agreements and through the World Data Center system. Other data sets are compiled at NGDC, frequently in cooperation with other government agencies or academic institutions. One of the best examples of the latter is the Index to Marine Geological Samples, or "Core Curators' Database".

Jan 1, 1993

By Brian D. Bornhold

A comprehensive multi-disciplinary marine geological survey of northwestern Graham Island, Queen Charlotte Islands, British Columbia, Canada was conducted by Offshore Survey and Positioning Services Ltd. of Vancouver, B.C. on behalf of the Geological Survey of Canada; Energy, Mines & Resources Canada, Pacific Geoscience Centre, Sidney, B.C. Canada during October 1984 and July 1985. The aim of the survey was to map both the surficial geology and geomorphology in order to identify and evaluate the nature of the nearshore sedimentation and recent tectonics including stability (slumps and scarps) seafloor faults (frequency and displacements) and both the classification and consistency of soil type boundaries and properties. Data was acquired by utilizing conventional indirect applied marine geophysical techniques including side scan sonar, precision echo sounding and complimentary soil sampling. During October 1984 a total of 320 line kilometres of data including 180 soil samples were acquired. During July 1985 a total of 300 line kilometres of data were acquired including 150 soil samples.

Jan 1, 1985