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A C-CORE study on behalf of the government of Newfoundland identified the inner continental shelf off northeast Newfoundland as having a relatively higher potential for hosting placer gold than other parts of the inner shelf. Under the auspices of the Canada-Newfoundland Cooperation Agreement on Mineral Development, the Geological Survey of Canada conducted a three-year project to map the distribution of surficial sediments and the abundance of placer minerals (particularly gold) from White Bay to Cape Freels. Much of the study area is a fjord coast, with steep rocky slopes and scattered gravel beaches. The extreme east, from Hamilton Sound to Cape Freels, has a wide, shallow inner shelf, sandy beaches, and extensive coastal dunes. Relative sea level was high in the late glacial period. It has fallen continuously in the west, but in the east it dropped to -19 m, before rising to within several metres of the present level by 3 ka. In terms of surficial sediments and processes, five zones are identified: (1) Deep offshore deep basins that contain thick postglacial mud overlying glacialmarine gravelly sandy mud. This zone is below a depth of 370 m in White Bay, 300 m in the Notre Dame Basin. 2) Basin transition zone in which the sea bed has been eroded by currents, so that glacialmarine sediments are exposed in places. Winnowing has formed an uppermost layer of muddy gravel. There is a slight potential for enhanced levels of fine particulate gold, but the gold would not be exploitable. (3) Iceberg impacted zone Above 200 m the keels of icebergs impact the sea bed, causing furrowing and pitting. Furrows predominate in deeper areas, and pits are concentrated at the inner boundary of this zone. Iceberg turbates have developed in shallow waters (60-100 m). Combined with winnowing, iceberg turbation could enhance the potential for concentration of fine particulate gold, but not into economic quantities. 4) Wave dominated zone Above approximately 60 m the sea-bed sediments are highly mobile due to waves, currents, and iceberg impact. Sand is either rippled or organised into sand waves. Gravel is either poorly sorted, and organised into

Jan 1, 1995

By Pierre-Yves Morvan

One of the numerous challenge for underwater mining is the positioning. This paper describes an architecture for the integration of an Ultra Short BaseLine (USBL), an Acoustic Synthetic BaseLine (ASBL) operating in Sparse Array mode and a Doppler Velocity Log (DVL) closely coupled with an Inertial Navigation System (INS) for precise subsea positioning in severe environments. By using such architectures, the INS can help to reduce the noise on the measurements coming from acoustic sensors. Another advantage is the capability to reduce the number of required transponders on the seabed, and as a consequence, reduce the time for the deployment and calibration of each transponder. The paper further describes sea-trials performed to assess the ability of a complete positioning system to provide decimetric positioning precision even with a single beacon deployed in the navigation area.

Jan 1, 2017

By V. Alexandrov

This paper presents the results of theoretical investigations of the energy requirements of the hydraulic lifting of mined materials from the seabed to the sea surface in the deep-sea mining of solid minerals such as manganese nodules in the Clarion-Clipperton region of the Pacific, situated on the sea floor in water depths of 4,500 m or more. The principal element of the developed underwater transport system is the Underwater Chamber, which is connected by flexible pipeline to a mining machine that gathers nodules from the seabed, mixes them with seawater, and feeds them into a flexible pipeline. In this paper, we discuss the question of the optimum water depth for placement of the Chamber, the interior of which is designed to maintain a 1-atmosphere pressure. We present a method for calculating this depth as it relates to the mechanical characteristics of solid particles, the shapes and size distributions of the particles, particle and slurry density, and other properties. These investigations were carried out in hydro-transport laboratory of the Saint-Petersburg Mining Institute and the hydraulic laboratory of Faculty Environmental Engineering in Wroclaw Agricultural University. KEY WORDS: deposit, nodule, flexible pipeline, pressure drop, concentration, hydromixture

Jan 1, 2005

By G. A. Tret’yakov, V. A. Simonov, I. Yu. Melekestseva, V. V. Zaykov, N. N. Ankusheva

The Kyzyl-Tashtyg massive sulfide polymetallic deposit is situated 120 km north-east of Kyzyl (the capital of Tuva Republic, Russia). It is located in the Ulug-O volcanic zone which is interpreted as the northern segment of the Kaa-Khem rift in Sayano-Tuva marginal sea, one of the Paleoasian Ocean margin (Fig. 1) [Zaykov, 2006]. Since its discovery in 1946 the deposit has been studied by many researchers. Significant information was published by Kuzebny et al. [2001] and Zaykov [2006] who proposed volcanogenic-sedimentary genesis. A single reference in English about Kyzyl-Tashtyg is available [Herrington et al., 1999].

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 Nobuyuki Okamoto

Ferromanganese crusts on the seamounts in the Pacific Ocean are potential resources of cobalt, nickel, platinum and REEs. Particularly, those of the Republic of Marshall Islands and the Federated States of Micronesia (FSM) waters are believed to be of the highest resources potential area in the Pacific Ocean. The total six cruises using the Japanese Research Vessel Hakurei Maru No. 2 were carried out in the seamounts of the Marshall Islands in 1996, 1998 and 2002, and of the FSM in the 1997, 1998 and 2005 for evaluation of economic potential for cobalt-rich ferromanganese crusts as part of the Japan-SOPAC joint project. During these cruises numerous data such as bathymetric, geological, geophysical and environmental data were obtained. Geophysical exploration with backscatter mapping and side scan sonar, visual imaging using towed TV camera and geological sampling using dredge bucket and/or benthic multi-coring system (BMS) were conducted on these seamounts. In this presentation, we will report the mode of distribution of the crusts and calculated resource estimation based on the results of these geological and geophysical shipboard survey and land-based analyses. Keywords: ferromanganese crusts, Marshall Islands, Micronesia, resource potential

Jan 1, 2011

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 Justin C. I. Baulch

In October 2004 Placer Dome entered into an exploration farm-in agreement with Nautilus Minerals, to explore for Submarine Massive Sulphide (SMS) deposits on Nautilus? PNG exploration tenements. Placer/Nautilus currently holds approximately 15,000 km2 of tenements in PNG waters, either granted or under application, covering all reported seafloor hydrothermal vent occurrences.

Jan 1, 2005

By Tatiana ?. Sedysheva, Vladimir V. Ivanov, Michail E. Melnikov, Irina A. Pulyaeva

"INTRODUCTIONHydrogenetic Fe-Mn crusts are ubiquitous in the ocean basins and play an important role in marine mineral-deposit research because of their widespread occurrence and high concentrations of valuable and rare metals. Directed research, which started in the last quarter of the 20th century, has provided significant results, with substantial amounts of data produced on Fe-Mn crusts structure, composition, and distribution in the global ocean [3, 4 - 8]. Now, commercial interests gain more and more attention. Mining systems are being developed which involve fragmentation of the crusts and their separation from the substrate. The effectiveness of such activities greatly depends on physico-mechanical characteristics of the crusts and rocks on which they form. This determines the importance of the engineering geological study of the objects.This article comprises the results of the engineering geological studies of the crusts samples (72 samples) and their underlying rock substrates (75 samples), which were carried out during the research cruises 6-06, 6-07, 6-08, 6-13 (2006-2013) on the Magellan Seamounts guyots in the Western part of the Pacific Ocean by the specialists of the State Scientific Centre Yuzhmorgeologia [10 - 13, 19, 20]. The authors of the article directly participated in the studies mentioned above.MethodsEngineering geological studies were carried out on board of the research vessel Gelendzhik and in the laboratories of NPA «Sevmorgeologiya». The studies involved the determination of the following parameters:"

Jan 1, 2017

By A. M. Olivarez

The elucidation of the theory of plate tectonics has provided a conceptual framework for understanding the formation and distribution of different types of ore deposits. For example, we now recognize that certain kinds of mineral deposits are generally associated with a particular type of plate boundary (i.e., massive sulfides often occur along divergent plate boundaries, whereas porphyry copper deposits are typically found along convergent boundaries). During certain geologic time periods, plate reorganization events have changed the relative proportion of different types of plate boundaries. Corresponding changes have been observed in the abundance and distribution of ores deposited during these times. The present study examines the temporal aspects of this relationship; i.e., do plate reorganization events play an active or passive role in ore formation? In other words, do plate reorganizations simply provide a more favorable tectonic setting in which ore formation can occur over significant time periods, or are they directly linked to the mineralization process? We have examined this question by comparing regional tectonic histories with the ages of known massive sulfide and porphyry copper deposits. Because these deposits, in particular massive sulfides, form as a result of hydrothermal activity, we have also compared regional tectonic histories with proxy indicators of this process in the marine sedimentary record. These indicators include increased mass accumulation rates of Ca, Fe, Mn, and opal, characteristic changes in the Sr/Ca and Mg/Ca ratios of biogenous carbonates, and shoaling of the carbonate compenstion

Jan 1, 1988

By N. R. Ayupova

Several metallogenic zones including Sakmara, Magnitogorsk, and East-Ural zones were revealed in the Ural fold belt (Fig. 1). These zones are considered to be the paleogeodinamic sectors corresponding to marginal sea, island arc system, and uplift respectively. Ferruginous-manganiferous sediments in the Southern Urals are hosted by the basalt-rich volcano-sedimentary series of the Magnitogorsk paleoisland arc system with West- and East Magnitogorsk island arcs and Sibai inter-arc basin. The manganiferous mineralization occurs in association with the Middle Devonian stratabound hematite-quartz rocks and bedded red jaspers localized on the foot or handing walls of massive sulfide deposits. Fe-Mn nodules are widespread in jasper horizons on the flanks of manganese deposits. We have studied Fe-Mn nodules from the Faizulino and Yanzigitovo Mn-deposits formed in the Sibai inter-arc basin and compared them with well known Fe-Mn nodules from modern oceans.

Jan 1, 2010

By S. Rajendran

Gas Hydrates (Methane Hydrates) are solid, ice-like substances composed of water and natural gas. They occur naturally in areas of the world where methane and water combine at appropriate conditions of temperature and pressure and are found in ocean bottom sediments and in some permafrost areas. Besides temperature and pressure, factors like bathymetry, sediment thickness, sedimentation rates, and total organic carbon content (TOC) also control gas hydrate formation in the ocean basins. The stability of gas hydrates depends on the critical combination of high pressure and low temperature (0 - 17 bars, 0 - 25°C), which in turn is dependent on the mix of gases from which the mineral is formed. As the critical parameters can be altered by deposition, erosion, slumping, formation or melting of ice cover, rise and fall of sea level, and sudden temperature changes induced by tectonic activities, current flow, or volcanisms, the gas hydrates tend to be very unstable. The Indian offshore is promising for the occurrence of gas hydrates in a total of about 80,000 km2 area in the bathymetry range of 700 to 3000 m as reported in earlier surveys. A gas hydrate stability zone thickness map was prepared using bathymetry and sea bottom temperatures along the continental margins of India. This map is expected to provide the depth window while searching for Bottom Simulating Reflectors (BSR). The study indicates that a minimum water depth of 750 m is required for the formation of gas hydrates, above which the chances for gas hydrate occurrence appear minimal despite other favorable conditions like organic-rich sediments, etc. Single-channel seismic analog records (Gupta et al., 1998) indicate that the Western Continental Margin of India (WCMI) offers a greater promise for gas hydrate occurrences, particularly with regard to the number of BSRs traced on the analog records as compared to earlier surveys.

Jan 1, 2005

By G. Cherkashov

A new hydrothermal field with massive sulfide deposits was discovered in 2004 at 16º 38.4?N, 46º 28.5?W on the Mid-Atlantic Ridge. Hydrothermal signals had already been recorded from bottom waters and sediments in this area during cruise 19 of R/V Professor Logatchev in 2000. This site was revisited during the 24th cruise of R/V Professor Logatchev in February 2004 when samples of massive sulfides were recovered and video records of the deposits made. The basalt hosted hydrothermal field is situated at a depth of 3700-3750 m, 600 m above the inner floor on the eastern slope of the rift valley. Structurally, the new field is located at the intersection of a deep along-axis marginal fault and a transverse sub-latitudinal dislocation. Six sulfide mounds as well as associated metalliferous sediments were mapped (sampled and/or recorded by video profiling) within the hydrothermal site. The largest ore body, 500 x 225 m, in the southern part of the field consists of small blocky talus and relics of sulfide chimneys partly covered by iron oxyhydroxides. The chimneys are 1-5 m high. The southern and western boundaries of the massive sulfide deposit have not yet been delineated. More than 1,100 kg of massive sulfides and stockwork mineralization were sampled at 7 sites by dredge and TV-grab. Everywhere, iron sulfides were the principal minerals present. Pyrite in association with lesser amounts of chalcopyrite occurs in both massive sulfides and stockwork mineralization. Of particular interest is the chalcopyrite-siliceous stockwork where silicified and chalcopyritized basalts are intruded by a network of chalcopyrite veinlets. These zones could be fairly thick and enriched in base metals. Sphalerite was very rare.

Jan 1, 2004

By Fernando JAS Barriga

The world-class Neves-Corvo deposits were intersected by drilling in 1977. They occur in the (Carboniferous) Iberian Pyrite Belt (IPB), Western Europe&apos;s largest stock of base metals (see Bamga, 1990, in Dallmeyer RD, & Martinez E, eds, Pre-Mesozoic Geology of Iberia, Springer-Verlag). Massive and stringer sulfides in the area sum up to about 200 Mt (109 kg), in five main orebodies (Neves, Corvo, Graca, Zambujal and Lombador). They include unique, extremely high grade copper and tin ores ( - 33 Mt Cu ores, -7.5% Cu, and -4 Mt Sn ores, -2.6% Sn, - 12.5% Cu). Also present are -50 Mt polimetallic ores (-6% Zn, 1.2% Pb, 64 ppm Ag). The remaining are relatively low grade pyritic massive and stringer sulfides (Cu < 2%. Sn < 1%, Zn equivalent < 4%). The geological setting is one of bymodal submarine volcanism, with predominant felsic, explosive volcanism and associated sedimentation (detrital and chemical), which took place on a shelf-facies, quartzite-phyllite basement (of Upper Devonian age). The plate tectonic setting has been the object of much debate. Current interpretations favour that the IPB volcanism took place in a tensional fore-arc region, associated with oblique subduction and collision (Silva et al., 1990, same volume as above). At Neves-Corvo there are many different ores, that may be grouped in four main types: fissural (at the base), breccia, massive (intermediate) and "ruban6 " (at the top). Fissural ores seem to correspond to stockworks in contrasting types of host rocks (gray to black shale, sericitic, chloritic and graphitic, and light gray volcanic rock). Massive ore may contain significant shaly gangue, at the base of individual orebodies, and silica-rich (cherty) varieties towards the top. The more sulfide-rich varieties predominate, and are usually well banded.

Jan 1, 1993

By John C. Wiltshire

Hawai&apos;i is surrounded by a series of potentially valuable marine mineral deposits. These include manganese nodules between Hawai&apos;i and Mexico, cobalt-rich manganese crusts and phosphorites in the Exclusive Economic Zone around the Hawaiian Island Archipelago, Johnston Island and the neigh- boring island states and sand and gravel deposits off the main Hawaiian Islands largely in State waters. Hawai&apos;i has an economy that is very narrowly based on the tourist industry. In an effort to avoid the difficulties coming from such a vulnerable economy, significant efforts have been made toward economic diversification. The State has set up a range of programs looking to find new industries. New ocean industries figure prominently among these efforts as Hawai&apos;i is surrounded by ocean. Naturally, among new ocean industries the potential for new marine mineral industries is significant given that Honolulu is the only full service port in the Central Pacific and Hawai&apos;i is in the middle of the mineral belt. The port of Honolulu is now being actively used by mineral exploration vessels of several countries and with the current number of ship visits varying from 10-15 per year, this puts several million dollars a year into the State economy. It helps to fulfill the State&apos;s goal of dynamic growth in the ocean sector of the economy. Nonetheless, a major marine minerals industry, particularly one which would involve processing of minerals in Hawai&apos;i, is controversial in a State whose main source of revenue is tourist expenditures based on the image of a pristine environment. In addition to the perceived threat to the hotel and fishing industry, is the whole highly emotional debate concerning preservation and development. To complicate the issue further, the major interest in developing a marine minerals is currently largely from Korea and China rather than from domestic U.S. industry. On the other side of the debate is the fact that the State&apos;s economy is hampered by many low paying jobs and a lack of technical jobs. This is further exacerbated by the fact that lower paying jobs are held disproportionately by people of Hawaiian and Pacific Island ancestry. Naturally, this leads over time to a certain amount of resentment. The higher paying technical lobs associated with a minerals processing industry could help to alleviate this problem.

Jan 1, 1996

By Luana Karvel, Lars Kullerud, Morten Sørensen, Øystein Halvorsen, Øivind Lønne, Elaine Baker, Tina Schoolmeester, Joan Fabres, Yannick Beaudoin

The UNEP Shelf Programme (USP) is the access point for a collaboration of international organizations with expertise in marine geoscience and maritime law. It was established in response to a United Nations resolution, stating that the United Nations Environment Programme (UNEP), working through the Global Resource Information Database (GRID) system, should work in conjunction with Intergovernmental Oceanographic Commission of UNESCO (IOC) and the International Hydrographic Organization, to assist coastal States, and in particular developing States and small island developing States (SIDS) with submissions to establish the outer limits of their continental shelf under Article 76 of the United Nations Convention on the Law of the Sea (UNCLOS).

By T. E. Sedysheva

The study of Co-rich manganese crusts has reached the level which allows to start prospecting works in the observable future, and furthermore, probably, exploitation of ore deposits. In this connection, among other goals, the necessity to analyze a distribution of ore bed parameters in details is quite urgent. Foremost, these are crust thicknesses in connection with landforms and elements of submarine mountains relief. This report is based on representative sampling made in course of research cruises run by SSC Yuzhmorgeologiya over guyots of the Magellan Seamounts. Crustal covers could overlie seafloor surfaces which are confined to a various landforms and elements of relief under the condition, that they are free of sediments. These are planed parts of a summit surfaces, edges, spurs, rectilinear parts of slopes, intermountain saddles and volcanic edifices. It is known, that crustal thicknesses are different at a various forms of relief [1]. We processed statistically the data around crustal thicknesses, which were sampled by dredging and submersible drilling (Tables 1, 2).

Jan 1, 2010

By Cheng Xiangzhou

The China&apos;s Pioneer area includes two parts. The topography in the western part is very different from that in the eastern one. The distribution of the manganese nodules in these two regions differs correspondingly China Ocean Mineral Resources Research and Development Association (COMRA) will take appropriate measures so that the next development will be adapted to the features of its potential minable area.

Jan 1, 1996

By Jan Willem van Bloois

IHC Merwede is world market leader in the construction of specialist dredging equipment; it is a company with a rich history. The Netherlands is a coastal western country for which water management is a very important issue. Without the enclosure of the coastal areas with dikes and dunes almost two third of the Netherlands would be flooded. These activities are mostly performed by the dredging industry and are the foundation of the dredging industry as it is today. Besides land protection this industry also carries out infrastructure maintenance and performs land reclamation projects. In essence the dredging industry is specialized in horizontal excavation activities and operations in shallow waters with the purpose of gathering bottom sediments and disposing it at a different location. The development is that the activities are moving to deeper waters to a depth of up to 150m. A few years ago IHC Merwede received a request to perform the shallow water excavation techniques at a depth of approximately 2000 meters for the deep sea mining market. In response to the increasing number of requests for deep sea dredging and mining application solutions, IHC Merwede combined all of its activities in this sector to create a new, specially equipped operational unit, IHC Deep Sea Dredging & Mining (IHC DSDM).

Jan 1, 2010

By Demoor Damien

"The exploitation of marine resources has enjoyed renewed interest with a completely new sector, that of the Deep Sea Mining of mineral resources in the seabed, that is now gaining momentum. Nevertheless, the significant environmental constraints represent a challenge for initiating these new activities, whether this is in terms of the knowledge of the concerned ecosystems or in terms of monitoring and minimizing the impact of these new activities. This paper presents 2 technologies that aim to respond to the expectations of the stakeholders in this area. The first consists of the real-time monitoring of installations/operations and their impact on the environment using the most modern underwater technologies and especially long-term deployment AUV based on AUV docking station solution and autonomous long term observatories. The second consists of a membrane allowing the confinement of an area, the reduction of the emission of particles in suspension and noise reduction.IntroductionDeep ocean environments have been explored since the mid-1800s. As the land-based reserves of hydrocarbons and minerals become depleted, increasing numbers of resourcebased projects are being proposed for shallow then deepwater environments. Two distinct resource sectors have recognized the potential commercial value of working in shallow and deepwater environments – Oil and Gas and now Mining."

Jan 1, 2017