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By Porter Hoagland

It is well known that significant quantities of mineral deposits exist in the oceans. Most of these resources cannot yet be classified as economic "reserves" in the strict sense of the term, but they serve as backstops to deposits of identical minerals produced onshore. The prospects for the commercialization of ocean mineral resources will depend upon factors affecting both supply and demand, including, among other things, changes in consumption patterns, technological developments, new discoveries, developments in markets for complements and substitutes, and environmental regulation. In this presentation, we examine broad trends in mineral prices, as one of the most summary measures of the prospects for the commercialization of ocean minerals. Further, we report on any recent developments in the relevant product markets that may affect the potential for commercialization.

Jan 1, 1996

By Alexander Malahoff

Mineral zonation studies were conducted on hydrothermal vents of two hot spot volcanoes. One study site is located within the Axial Caldera of the axial hot spot volcano of the Juan de Fuca Ridge. The young high-temperature hydrothermal vent field consisting of two polymetallic sulfide chimneys, five meters high, located at 130°01.5'W, 45°56.5'N, along a fault complex at the base of the southwestern wall of Axial Caldera was sampled during four ALVIN dives in 1983. Temperatures of up to 270°C were measured within the orifice of one of the chimneys, which was then broken off and recovered with the submersible. Both black and white "smoke" was observed to be emanating from the one chimney sampled. The high-temperature chimney extends directly from a field of broken lobate lavas which are located at a water depth of 1,550 meters, about 200 meters east of the caldera wall. The chimney makes one of the shallowest active high-temperature vents studied to date. The vent is surrounded by clumps of vestimentiferan worms and is located within an elongate field of red-colored iron smectite blankets and chimneys. The low-temperature field forms a ribbon 150 meters wide, extending for about 1,300 meters at the base of the wall. Chemical analyses of the hydrothermal deposits ranging from the polymetallic sulfides of the chimney to the outer zones of the low-temperature field show a range of elemental assemblages consistent with temperature zonation around the vent. Chemical zonation within the high-temperature

Jan 1, 1988

By U. Schwarz-Schampera, C. Rühlemann, H. -R. Kudrass

Within 2006 BGR will conclude a contract with the UN International Seabed Authority (ISA) for the exploration of polymetallic nodules. The contract covers an area in the Pacific nodule belt between the Clarion and Clipperton fracture zones, that which is about 75.000 km2 in size at water depths between 4200 and 5000 m (see Fig. 1). Up to now, 7 consortia or state parties have acquired similar exploration “licenses” for polymetallic nodules in the central Pacific Ocean and the Indian Ocean. These licenses of the UN authority are required according to the UN convention on the law of the sea (UNCLOS) as the areas of interest are located outside of national EEZs. The “licenses” then reserve exclusive rights to the applicant for a time span of about 15 years.

Aug 24, 2006

By Michael Goldin, Jonathan Ladner, Thomas Peacock, Nathaniel Johnson, Patrick Haley, Kris van Nijen, Andrew Rzeznik, Pierre Lermusiaux, Matthew Alford, Carlos Munoz-Royo

Surface processing vessels for deep-sea nodule mining operations will produce dewatering plumes that will be released at some depth into the ocean water column. We are studying all aspects of this part of the nodule mining process. First, we have developed analytical and numerical models to determine the effects of highly non-uniform, realistic stratifications on forced, compressible plumes with finite initial size. The classical plume model is developed to take into account the effects of compressibility and thermal conduction through the dewatering pipe. Our results show how small-scale features of a realistic stratification can have a large effect on a plume, and provide a basis for determining at what depth dewatering plumes can be released. These results form the basis for our PLUMEX field experiments, in which we will study the dynamics of dewatering plumes over the course of one week of field tests from the vessel R/V Sally Ride. The field experiments will use a Remotely Operated Vehicle (ROV) and a Phased-Array Doppler Sonar (PADS) system to study the characteristics of the dewatering plumes. The subsequent transport of the material in the dewatering plume will be monitored via shipboard surveys and, potentially, Autonomous Underwater Vehicle (AUV) operations, and these studies will be integrated with near real-time, data assimilating numerical model predictions. The ultimate goal of this project is to develop a field validated, recommend strategy for the release and monitoring of dewatering plumes, to help inform the development of ISA regulations and the planning of industrial operations.

Jan 1, 2017

By Evgeny G. Gurvich

While direct study of high temperature hydrothermal activity and the associated mineral formation as well as study of their scales are possible in the modern ocean, researchers are deprived of such opportunity for past geologic time. Even in cases where hydrothermal deposits that formed in the geological past are preserved they have been covered by sediments or overlain by lava and have become inaccessible after a time for obser-vation and sampling. Rarely are these buried hydrothermal deposits found during deep-sea drilling or coring operations, and their direct study on an ocean scale is impossible at present. Even within hydrothermal fields, without special preliminary detailed surveys, the probability of intersecting hydrothermal edifices that are covered by sediments becomes a rare event.

Aug 24, 2006

By Katherine H. Walton

The research affiliate projects of the Continental Shelf Division of the Marine Minerals Technology Center concentrate on the development of technologies and methodologies for the exploration 4 and assessment of nonfuel continental shelf mineral resources within the U.S. Exclusive Economic Zone. Three of the FY 1990-91 research grants are summarized below. Scientists at the Center for Applied Isotope Studies at the University of Georgia have developed ?An Advanced Design for a Seafloor Gamma Isotope Mapping System? for the rapid collection of data on seafloor sediments. This system is designed to detect gamma radiation emitted by naturally occurring radioactive elements found in marine sediments. This data can be used to study seafloor lithology and has direct application in marine mineral surveys. The purpose of this study has been to redesign and calibrate the system for marine mineral survey work. Recent modifications of the sled design, gamma radiation detector, and supporting software have resulted in considerable improvements in sensitivity, functional operation, and data acquisition.

Jan 1, 1991

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 Andrea Koschinsky

Recent technological breakthroughs in the fields of ceramics, medicine, aerospace engineering and electronics (semi- and superconductors) are constantly creating new uses and an ongoing increasing demand for a variety of rare valuable trace metals. These so-called high-tech elements such as hafnium (Hf), titanium (Ti,) niobium (Nb), tantalum (Ta), zirconium (Zr), molybdenum (Mo), vanadium (V) and the rare earth elements (REE), many of them of strategic importance, occur inter alia at elevated and potentially economic concentrations in marine ferromanganese nodules and ferromanganese crusts, making those deep sea deposits potential future resources of these metals. As these metals are mostly present in the lattice of the manganese and iron phases, which are strongly intergrown, rather than in separate mineral phases within the nodules and crusts (Koschinsky and Hein, 2003), reductive dissolution of the host phases is a prerequisite to release and dissolve the valuable metals. To evaluate the association of these rare valuable metals with their mineral carrier phases, sequential leaching experiments were carried out on selected samples in a first step in our project.

Jan 1, 2011

By Hjalmar Thiel

Issues of deep-seabed mining are discussed since four decades and extensive efforts have been invested in oceanographic studies related to environmentally sound harvesting of polymetallic nodules. Because mining on the deep seafloor seems to range from large-scale, two-dimensional dredging or scooping up of the ore from the uppermost surface sediment layer to more localized drilling or deeper digging into a three-dimensional ore body, it appears to be justified to reconsider some concepts for environmental impact evaluation. Based on the experience gained during preceding years in environmental studies related to polymetallic nodule mining, some interrelated hypotheses and proposals will be presented. It is suggested that these proposals be considered in future plans for environmental impact evaluation and that observations on community re-establishment be conducted before massive sulphide mining or other ore extractions enter the commercial mining phase.

Aug 24, 2006

By Andrew E. Grosz

The Atlantic Continental Shelf (ACS) of the United States includes about 391,000 km2 extending from the shoreline to the 200-m isobath. It varies in width from a fraction of a kilometer (offshore of southern Florida) to about 150 km (offshore of Cape Cod, MA). The contained volume, of sand and gravel is estimated to be on the order of 3-7 x 1.011 m3. Concentrations of potentially commercially important heavy minerals (HM) exist locally, particularly in high-energy depositional environments (for example in channels, tidal deltas, ridge and swale areas, and submerged former shoreline complexes). Recently completed and ongoing studies of HM assemblages in vibracore samples from the south shore of Long Island Sound, NY, offshore of Ocean City, NJ, offshore of Cape May, NJ, offshore of the mouth of Chesapeake Bay, VA, offshore of Myrtle Beach, SC (grab samples), and the ACS offshore of Florida provide the information base for this presentation (Table 1). The surficial sediments of the ACS contain local concentrations of HM that compare favorably to those in currently mined onshore deposits as shown

Jan 1, 1988

By Charles W. Finkl

Coastal and marine aggregate (sand and gravel) mining on US continental shelves is a major activity that supplies industrial and commercial demands for these raw materials. Because Pacific, Atlantic, and Gulf coasts contain significant shoreline segments that are in a critical state of erosion, sand-gravel and mixed sediment (sands with a high percentage of silt-plus-clay) deposits are mined in efforts to mitigate land loss. Sandy shores, and to a limited extent gravel coasts, erode by shoreline retreat due to relative sea-level rise and sediment starvation in littoral drift patterns. Mostly gravel shores occur in high latitudes and shorelines often advance seaward due to isostatic rebound following the LGM (Last Glacial Maximum 18,000 YBP). Sandy and fine-grained shores occurring in middle and low latitudes of the conterminous United States are problem coasts that require beach renourishment and reconstruction of barrier islands. Muddy coasts of the Mississippi Delta region are especially problematic because some islands are literally disappearing in response to subsidence. Replacement of sediments lost to the littoral drift system or returned to sedimentary sinks by drowning is thus a critical endeavor that involves annually dredging hundreds of millions of cubic meters of sediments from the continental shelf area. The types of shelf sediments that are amenable to marine mining techniques, their occurrence, and means of detection are highlighted in this paper. Minable Sediments on the Continental Shelf Wide varieties of sedimentary bodies that occur on the continental shelf are amenable to mining for beach renourishment and barrier island (beach-dune-marsh system) reconstruction. Relict terrestrial deposits make up a small but important proportion of shelf sediments that were deposited on coastal plains, now drowned by the post-glacial sea-level rise to form continental shelves. Examples of these deposits include drowned moraines, outwash plains, eskers, and kettles along the northern Atlantic coast in addition to siliciclastics along middle latitude Pacific, Atlantic, and Gulf coasts. Special cases include carbonate sequences along tropical costs of Florida and the muddy coasts of deltas, mostly in Louisiana. Specific types of minable deposits thus include shoreface attached sand sheets, dunes, and ridges in addition to offshore inter-reefal sands (between coral reefs in the Florida Reef Tract), bank deposits, and sand waves (ridges) that extend into US territorial waters. Nearshore siliciclastics include ebb-tidal deltas and bars. Drowned river valleys occur along all three US coasts and can be exploited for their fluvial sands if the covering mud sheets are thin.

Jan 1, 2005

By Michael J. Cruickshank

A workshop to examine recovery systems for selected strategic and critical materials in the U.S. National Seabeds for the National Defense Stockpile in the 21st Century was held in Hawaii September 26-28, 1991, sponsored by the National Science Foundation and the Marine Mineral s Technology Center. The National Defense Stockpile of critical and strategic mineral commodities is presently in a deficit position of more than 7.5 billion dollars. Current domestic reserves of some commodities are limited or nonexistent. As defined by the U.S. Bureau of Mines, "Reserves are select resources . . . which at the time of classification, can be mined at a profit." Occurrences of these minerals have been discovered offshore within U.S. jurisdiction. If the technology could be developed to convert these resources into usable ore reserves, our dependence on foreign ores could be greatly reduced. Preliminary estimates indicate that a ten-year program of ore reserves definition, with appropriate technical developments to demonstrate a recovery system, could cost less than half the amount authorized for stockpile acquisition in FY 1989 alone.

Jan 1, 1991

By Leticia Rosales Hoz

A chemical and geological study of beach samples from the Mexican North Pacific was undertaken in order to evaluate the chemical composition of the beach sediments and it s association to lithology, climate, topography and weathering. The North Pacific Mexican littoral is characterized by arid weather with wide coastal plains and three geological provinces. The sands from the area are mainly finer, well sorted and show high maturity because of the high wave regime and the high energy conditions produced by the California Current in the coastline. The provenance index reflects that the region has a source of deep seated rocks, now exposed and dissected. Factor analysis made using the chemical composition showed the samples can be differentiated by five factors: 1) SiO2, 2) Al2O3; 3) Cu; 4) Sr and P2O2 and 5) Na content. Samples located in the northof the study area showed the highest values of Fe2O3 (17.72%), TiO2 (2.43%), V (576 ppm) and Zn (141 ppm) associated to methamorphic rocks present in the area.

Jan 1, 2000

By Amy Gartman

"Seafloor hydrothermal systems result in the emission of abundant particles and nanoparticles into seawater1. Many of the elements in these particles settle locally, although some are transported distally to the global ocean2. Although broad similarities exist, the mineralogy, size and therefore reactivity of particles emitted varies between sites in the global ocean, and even within sites at the same vent field. The particle geochemistry of these vent fields is a critical but little understood component both from a perspective of baseline characterization and potential environmental impacts.The mining of seafloor massive sulfides formed from hydrothermal venting will generate a new class of particulates in the deep ocean. Broadly, black smoke and SMS tailings exhibit similarities including abundant Cu, Fe and Zn sulfides, and a large number of submicron particles. In addition to the major minerals, minor minerals including As, Bi, and Pb are present, especially in back arc settings. However despite broad similarities, natural “black smoke” and crushed sulfides created during mining operations differ significantly in size class, morphology, abundance, and reactivity. A comparison of these two classes of particulates will be presented, including chemical composition and reactivity to dissolution and oxidation."

Jan 1, 2017

By Peter M. Bartlett

The Republic of South Africa ranks among the world leaders in both reserves and production of numerous land-based mineral commodities. Over the last three decades, however, South Africa has also identified several commodities that may exist in commercial quantities in the marine environment. The major targets include 1) placer diamonds; 2) titanium- and zirconium-rich beach sands; 3) sedimentary and concretionary phosphorite and glauconite deposits; 4) manganese nodules; and 5) hydrocarbons. South Africa ranks second in world reserves of diamonds and has potentially enormous sea resources. Diamonds are currently recovered on the Atlantic side from ancient beach gravels in the Northwest Cape Province and from the seabed south of the Orange River to Lamberts Bay. Approximately 100,000 carats (or just 1% of South Africa's total annual production) are produced each year from offshore operations. DeBeers is investing approximately $5 million per year on sea prospecting activities and currently operates three vessels in offshore recovery operations. Diamonds recovered at sea will remain a small percentage of total production because of huge land-based reserves that are mined at a fraction of the cost of seabed operations.

Jan 1, 1986

By Carl H. Hobbs

The beach at the resort city of Virginia Beach, Virginia has been and increasingly will be dependent upon artificial nourishment for maintenance and for hurricane protection. Both existing base-level maintenance operations and planned substantial enhancement programs out strip the capabilities of traditional terrestrial resources to provide the required quantities of sand. Our research program, an amalgam of projects from several funding sources, has located and defined suitable quantities of beach quality sand for use on the city's beaches. The work also has furthered our understanding of the region's Quaternary history. Initially, reconnaissance level, high-resolution, sub-bottom profiles and surficial grab samples taken on the basis of sub- marine geomorphology identified two geographically and geologically separate areas worthy of further exploration. Further profiling supplemented with some cores further defined the potential sand reserves. The Sandbridge Shoal site is a large and discrete Holocene sandbody atop late Pleistocene strata. The sands in region offshore of the commercial area known as the Resort Strip appear to be recent fill within fluvial(?) channels cut into the older subsurface. Each of these resources is within roughly 5 km of major sites targeted for beach nourishment and/or hurricane protection and contains sand with appropriate geotechnical properties. Ongoing work will better define the dimensions and limits of the sand bodies and provide data to enable determinations to be made concerning exploitation. Ultimately decisions concerning the overall beach enhancement-hurricane protection projects will involve economic, environmental, technical, and social considerations.

Jan 1, 1995

By Sally Philpot, Siân E. Boyd, Hubert L. Rees, Emma Bee, Carla Houghton, Ceri James, Silvana N. R. Birchenough, S. Limpenny David, A. Coggan1 Roger, Koen Vanstaen

Every year approximately 22 million tonnes of marine sand and gravel are dredged form British waters. The eastern English Channel (EEC) contains substantial reserves, a proportion of which have been identified by the aggregates industry for potential future exploitation. The main aim of this study is to produce broadscale marine habitat maps of the EEC area. The UK aggregates industry has formed a consortium of representatives (the eastern English Channel Association), and have sponsored an initial baseline survey and follow-up sampling programmes as part of a Regional Environmental Assessment (REA) covering a patchwork of aggregate prospecting areas. To complement this effort, a large-scale geophysical survey was conducted in 2005 to place the REA in a wider spatial context and, thereby, to help assess the environmental significance of any future impacts arising from commercial aggregate extraction over the broader region of the EEC.

Sep 24, 2006

By Hal Palmer

A number of Articles contained in the United Nations Convention on the Law of the Sea III (UNCLOS) bear directly on legal issues related to the recovery of mineral deposits on the ocean floor. Mineral resources of the continental margin other than oil, gas and hydrates include, sand, gravel, shell, coral, gemstones and phosphorite. Jurisdiction over the exploration and exploitation of these deposits is determined either by the Territorial Sea claims of a coastal state or their recognized sovereign rights in the Exclusive Economic Zone (EEZ). At least 33 coastal states have the right under Article 76 (Continental Shelf regime) to claim seabed jurisdiction beyond 200 nautical miles (EEZ limit). In addition, several states have "Pioneer Investor" status with regard to seabed resources in international waters (The Area). A global maritime boundary database (GMBD) has been developed as a basic resource identifying the current claims of coastal states. It provides detailed information on existing boundaries and limits determined by the UNCLOS accords or by multi-lateral agreements which affect mineral exploration and exploitation. This paper will describe the GMBD and its construction and maintenance.

Jan 1, 2000

By Frank Manheim

The purpose of this presentation is to review the history of offshore non- fisheries resource development since World War II, as an introduction to a planned symposium on offshore resources scheduled for the 1996 UMI Conference. After World War II the United States became the leader in offshore oil and gas production, deep ocean drilling technologies, offshore terminals, platforms and production systems, and natural gas recovery and transport. Wartime skills in acoustic profiling and antisubmarine warfare were transferred into commercially important geophysical exploration techniques. The application of ocean drilling and geophysical techniques permitted the recognition and elucidation of plate tectonics patterns, development of seafloor spreading theory, and the transformation of our knowledge of seabed and subseabed strata. After John Mero's studies and recommendations for developing marine manganese nodules in the late 1950's interest in nonfuel minerals grew rapidly. The formation of international deep sea mining consortia in the 1960's was accompanied by a flurry of ocean engineering development, minerals prospecting and associated environmental studies The Santa Barbara Oil Spill of 1969 resulted in a moratorium on both offshore energy and minerals leasing by the Depart- ment Interior, and catalyzed the development of new Federal legislation in 1972. In 1973 the offshore energy moratorium was lifted in response to the Arab oil embargo, and offshore energy activities surged for a time. Minerals were reopened to leasing following President Reagan's 1983 executive order implementing a 200 mile EEZ. Although interest was spurred by

Jan 1, 1995

By Gary J. Massoth

Are hydrothermal emissions from subduction-related volcanic arcs important to the total hydrothermal burden of the oceans? While historical observations of hydrothermal venting of fluids at mid-ocean ridgecrests, intra-plate hotspots, and backarc spreading centers are numerous, we remain poorly informed regarding the contributions from hydrothermal systems associated with oceanic submarine arcs. Here we report the chemical results from the first systematic assessment for hydrothermal activity at an intra-oceanic arc front. We discovered that 7 of the 13 submarine volcanoes that define a 260-km-long segment of the southern Kermadec arc north of New Zealand are hydrothermally active. Most significant here is that the chemical compositions of the various hydrothermal systems, inferred from back-extrapolation of observations of hydrothermal plumes, are diverse, and in many instances enriched in the concentrations of gases (e.g., CO2 and H2S) and metals (e.g., Fe and Mn) compared to effluents commonly discharged from mid-ocean ridges. If our results are generally representative of submarine arcs, whose global extent may equal one-third that of ridgecrests, the answer to our leading question could be a resounding yes in terms of both volume and chemical composition.

Jan 1, 2001