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By Campbell McKenzie

Substantial consideration has been given to the implications that the morphology of the Chatham Rise deposit will have on mining operations. The glacio-tectonic processes involved in the distribution of nodules on the rise has in several areas been quite significant. The recent cruises by Chatham Rock Phosphate Limited (CRPL) have collected data which has affirmed the assumptions previously made and catered for in historic resource estimations. The deformation and displacement of the phosphorite during glacial periods and the redistribution of the mobile sand during interglacial periods is interpreted to have produced a highly variable pattern of phosphorite concentration (kg phosphorite/m2) and coverage (% phosphorite/sample weight). The phosphorite resource probably has a significant spatial variability at a scale of tens of metres. Results of recent surveys show phosphorite-rich patches alternating with phosphorite-poor areas at distances of less than 20 m. The high spatial variability of the deposit has had a bearing on how historical information for the project has been regarded and integrated with the recent exploration approach and data collection process. This coupled with the proposed extraction tool has influenced the size, nature, extent and siting of the proposed mining blocks

Sep 14, 2011

By Maria Baker, Kristina Gjerde, Lisa Levin, Verena Tunnicliffe, Lenaick Menot, Rachel Boschen

Deep-sea mining is rapidly approaching the test-mining phase to prepare for commercial mining in multiple oceans, both in areas within and beyond national jurisdiction. The first test-mining operations are likely to focus on seafloor massive sulfides found at active and inactive hydrothermal vents within national jurisdictions – possibly in the coming months. Beyond national jurisdictions, the International Seabed Authority (ISA) is developing the regulations to oversee exploitation of polymetallic nodules, massive sulfides and cobalt crusts. The Deep Ocean Stewardship Initiative (DOSI) minerals working group has, over the last 3 years, made formal submissions on the regulatory framework, on the draft exploitation regulations, on the article 154 review of ISA and on the initial environmental regulations. In advance of both test and commercial mining, we urgently need to identify and develop comprehensive, ecosystem-based management practices for deep-ocean environments subject to mineral extraction. Transparent criteria for deep-sea institutional and corporate social responsibility also need to be established. Proactive development of management practices, frameworks and policy prior to the onset of mining will facilitate some degree of protection and preservation of the marine environment, whilst enabling the use of seabed mineral resources. The DOSI minerals working group constitutes a broad spectrum of scientific, industry, legal and policy expertise. We provide expert opinion, both in collated and individual response forms, on deep-sea mining related concerns to ISA and national bodies. Our publications and workshops on key concepts raise awareness and provide scientific updates on ecosystems targeted for mining. See http://www.dosiproject. org minerals working group and join us to further this work.

Jan 1, 2017

By Satya Nandan

The International Seabed Authority is currently considering regulations for prospecting and exploration for polymetallic sulphides and cobalt rich crusts. The deposits of these two types of minerals are very different from polymetallic nodules for which the Authority has already adopted regulations in 2000. The presentation will discuss the nature of the deposits, the inadequacy of information and data concerning these deposits and their environment, as well as the problems of defining the method of allocation and the size of the areas to be licensed for exploration, and those to be retained for exploitation; the current status of the draft regulations being considered by the Council of the Authority.

Aug 24, 2006

The chemical composition of the nodules varies with the type of manganese minerals and the size and characteristics of their nucleus but those who have an economic interest have nucleus, generally : Mn> Fe> 6> Si> Al> Ba> Ni> Cu > Co. The Pacific Rim is an area of abundant occurrence of polymetallic nodules and the Pacific sea floor of the Clarion-Clipperton Zone (CCZ) is one of the most interesting areas in regard to the genesis of polymetallic nodules. Their abundance in the ocean floor is very variable, as there are places where they cover more than 70% of the ocean floor. The nodules can be found at any depth, but the highest concentrations are between 4000 and 6000. Hydrothermal processes that occurs near the East Pacific Rise at 21° N, may inputs metallic elements to nodules and to pelagic sediments, especially in regions close to the dorsal, as a greater influence hydrogenetic processes are present westward Metals such as Cu, Co, Ni, Sn, Fe, Mg, Pb, Zn and Ba show a relationship with the East Pacific hydrothermal activity and sea currents carry these metals in solution to the Clarion-Clipperton fracture area, where there are hydrogenic metals sources (Al, Fe and Mn).

Sep 14, 2011

By Natsumi Kamiya

The Metal Mining Agency of Japan (MMAJ) has started the project in the fiscal year of 1989 under the administration of the Ministry of International Trade and Industry '(MITI). The purpose of this study is to assess the impact on the ocean environment caused by manganese nodules mining. Summary of research and survey of MMAJ is as follows: 1. Evaluation of environment impact The aim of this study is to assess impact for ocean environment by manganese nodules mining. It is studied by using three-dimensional hydrodynamic prediction model and by carrying out cultural experiment of surface fauna with adding deepsea water and sediment. Development of hydrodynamic prediction model for discharged water at ocean surface has started in 1989. On board cultural experiment was carried out in the Japanese application area in the eastern Pacific in May 1991 and in May 1992.

Jan 1, 1993

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 Glen Smith

Nautilus Minerals is the world leader in exploration and development of deep ocean seafloor massive sulphide (SMS) resources. The company is currently focused on generating its resource pipeline in the Western Pacific and its first development project for recovery of high-grade copper, gold and silver mineralisation from its Solwara 1 site in the Bismarck Sea, Papua New Guinea. The Solwara 1 site is located at a water depth of 1,600 ? 1,800 meters. Over 150 SMS seafloor surface samples have been collected from chimney structures during dives made by remote operated vehicles (ROVs). In order to obtain an understanding of the sub-surface mineralisation, Nautilus carried out 4 drilling programs between 2006 and 2010 which allowed the calculation of a Canadian NI43-101 compliant resource estimate. The initial 2006 campaign was based on conventional offshore surface driven drill equipment. In conjunction with the subsea remote technology industry, Nautilus subsequently developed an ROV operated seafloor drill system with improved drill core recovery and efficiency. This technology was developed further with a 2010 - 2011 drill program to increase the available geological knowledge at Solwara 1 and adjacent prospects. his paper will provide an overview of Nautilus? SMS drilling requirements and recap the evolution of drilling technology and operations undertaken at Solwara 1 from 2006 to 2011. The paper will also discuss the potential of further developments in drilling techniques and equipment to increase or improve drilling depth, efficiency and data quality.

Jan 1, 2011

By Audrey Boissier, Marie-Anne Camon, Cecile Cathalot, Yves Fouquet, Laurent Bignon, Arnaud Agranier, Ewan Pelleter, Sylvain Bermell, Florian Besson

INTRODUCTION In October 2014, on behalf of the French government, Ifremer, along with the International Seabed Authority (ISA), signed a contract to start a detailed exploration program for seafloor massive sulfide (SMS) deposits in the work plan located on the slow spreading Mid-Atlantic ridge (MAR). The contract has a fifteen-year lifetime and the related exploration program must include the outline of SMS deposits and a resource assessment, as well as detailed environmental base line studies in the contract area. The exploration for SMS deposits generally includes detection of hydrothermal plume anomalies, acquisition of surface and near-bottom geophysical data, sampling operations from the research vessel (e.g. dredges, cores), and dive operations. The environmental studies include, among others, short and long-term oceanographic measurements, water column studies, biodiversity evaluation close and far from SMS deposits, characterization of natural hydrothermal plumes and related sedimentation. The HERMINE research cruise held from March 13th to April 28th 2018 (R/V Pourquoi Pas?) was the first cruise dedicated to exploration of active and inactive SMS and to the quantification of natural chemical input to the water column. The HERMINE cruise strategy was built up around three main objectives: (i) regional exploration including the detection of plume anomalies and the research of SMS deposits, (ii) local exploration of a SMS district and (iii) integrated study of a natural hydrothermal plume. This 3-in-1 cruise required us to optimize the switch between dives and surface operations. Day-time was devoted to dive operations whereas night-time was mostly dedicated to CTD/Rosette operations. The Nautile HOV (Human Occupied Vehicle) was well suited to the working time schedule of the cruise because it was time efficient in shorter (i.e. < 10h) dives due to fast descent and ascent speed, fast submerged forward speed, high maneuverability and the ability to carry heavy science payload as well as large volume of samples. Regional Exploration The first seventeen days of the HERMINE cruise were devoted to regional exploration, i.e. the detection of new plume anomalies and the research of new sulfide mineralization in the French work plan (10 000 km2; 6 clusters).

Jan 1, 2018

By William D. Siapno

Approximately a century lapsed between the time nodules were discovered and the beginning of commercial exploration in the early 1960&apos;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&apos;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 Georgy Cherkashov, Vladislav Kuznetsov

The presentation describes new data concerning the age of the Mid-Atlantic Ridge (MAR) hydrothermal fields. The collection of massive sulfides recovered from six hydrothermal fields has been dated using the 230Th/U method. The range of the data obtained is rather wide: from 2.2 up to 65.1 thousand years BP. Three stages of hydrothermal activity were detected for this 65 Kyr period of geological evolution: modern (0 -5), 20-25 and 58–65 thousand BP (Figure 1). This conclusion was confirmed by dating the associated metalliferous sediment layers which also indicate the hydrothermal events led to the formation of sulfide mineralization. There is a correlation between the age and size of massive sulfide deposits: older deposits are larger (Table 1). This and other applications of obtained data will be discussed in presentation.

Aug 24, 2006

By Tetsuo Yamazaki

Manganese nodules, seafloor massive sulfides, and cobalt-rich manganese crusts in deep-sea areas have been considered as future metal sources (Mero, 1965; Halbach, 1982; Lenoble, 2000). Manganese nodules were the first recognized deep-sea mineral resource and many efforts concentrated on the R&D of mining systems (Welling, 1981; Herrouin et al., 1989; Yamada and Yamazaki, 1998) and assessment of environmental impacts (Burns et al., 1980; Foell et al., 1990; Yamazaki and Kajitani, 1999). No mining venture, however, has been active for this potential resource. The reason is that the rate of world economic growth has been slower than anticipated in 1960s. During the 10 year period of 1994-2003 (Fig. 1), on the other hand, there was about a 33% increase in the world copper demand. Of that increase, about 60% was consumed by China. Most of China?s increased copper demand took place over the final 4-5 years of that period. The growth is expected to continue for several years, and in 10 years or sooner the same situation is expected for India. Copper is the third metal in global demand, but its small abundance in the Earth?s crust is not well recognized (Table 1). From the production rate and the abundance, a copper shortage, or crisis, has a high probability than the other metals. Japan has no domestic copper resources and needs a counter measure for this potential coming copper shortage. Fortunately, Japan has a manganese nodule mining claim in the Clarion-Clipperton nodule field, Kuroko-type massive seafloor sulfide deposits in the Okinawa Trough and Izu-Ogasawara areas, and cobalt-rich manganese crusts around Okinotori-Shima and Marcus Islands. We need to re-evaluate their potential as copper resources and to realize their development.

Jan 1, 2005

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 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 Lénaick Menot, Anne-Sophie Alix, Charline Guérin, Sébastien Ybert, Ewan Pelleter, Florian Besson

Ifremer, on behalf of the French government, holds an Exploration Contract with the ISA for polymetallic nodules in the CCFZ. As part of its exploration activities, the NODULE (2015) cruise was conducted to acquire a 50 m resolution bathymetric coverage of the eastern sectors of the Contract. In 2017, Ifremer initiated an update of the Contract’s mineral resource estimate. Metal grades and nodule abundance were modelled using ordinary kriging. The inferred mineral resource is 436 Mt (wet) of polymetallic nodules at an average abundance of 10.7 kg/m² with a cut-off grade of 7 kg/m². Based on the geological data, seamounts, sedimentary basins and steep slopes contain no nodules. Technical studies of most of the contractors have determined that nodule collectors could not maneuver on slopes above 5 to 10°. Thus, Ifremer has selected a quite conservative slope threshold of 7 % (about 4°) and a backscatter threshold of -29.5 dB to delineate nodule-free areas. This has a significant impact on the resource estimate, as about 54 % of the eastern Contract areas are excluded. Near-seafloor high-resolution mapping and photographic transects, associated with finer-spaced box-core sampling could constitute a next step to better constrain the mineable areas and to get a higher level of confidence in the resource estimation.

Jan 1, 2018

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 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 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 S. Jeffress Williams

Continental shelf margins are dynamic sedimentary environments that contain important benthic habitats and support many functions such as navigation, national defense, cables, pipelines, trawling, and oil and gas and mineral extraction. Coastal margins also contain resources such as sand and gravel aggregates, which are becoming increasingly important for beach nourishment to mitigate coastal erosion and enhance recreation and to restore degraded coastal ecosystems. Existing geologic maps of the seafloor and sub-bottom sedimentary character, morphology, texture, composition, and other seafloor properties are not available for some regions, are out of date and not inclusive of the massive data collected during the past several decades, and are not in GIS-based digital formats. New geologic maps, based on unified and integrated national digital datasets, showing the sedimentary character of continental margins are critical tools for both research to better understanding the geologic history and processes of continental margins as well as the distribution of habitats and resources and for managing coastal-marine resources. The majority of existing seafloor maps are decades old and do not include recent data from mapping surveys, seabed sampling and observation carried out by federal agencies, universities and industry. Because continental margins are increasingly important, comprehensive and integrated databases are needed to produce GIS-based digital maps displaying information such as seafloor geology, sediment character, texture and distribution. To meet the need for a unified database of seafloor sedimentary character, the USGS is conducting the Marine Aggregate Resources and Processes project, a national assessment of marine sand and gravel with federal, state, and academic partners.

Jan 1, 2004

By Wonn Soh

As for Earth, where human beings live, approximately 70 % of its surface is covered by oceans. Today, advanced technology has led us to understanding the abyssal ocean floor through the use of submersibles and ROVs (remotely operated vehicles) for the last 30 years. Furthermore, the oceanic crust beneath the abyssal floor still remains an unexplored scientific frontier due to the lack of a direct approach. Exploration of this frontier is required to enhance our understanding of the mechanism of the M.8 class plate-subduction-type earthquake, of generation of the big tsunami, that caused the disaster, and of the paleo-global environmental change as well as of the origin of life as viewed in deep water thermal vents.

By Robert M. Owen

Geochemical exploration for marine placers involves the acquisition, processing, and interpretation of geochemical data. Recent technological advances such as in-situ analysis systems and microcomputers have greatly improved our ability to acquire and process data, but their full benefits cannot be realized until we also develop improved methods for reducing and interpreting large amounts of raw geochemical data. Toward this end, our research has sought to identify existing and/or develop new geostatistical techniques for use in marine placer exploration. Each technique has been tested by evaluating its performance in the analysis of existing data sets. The data sets typically include the results of chemical analyses of suites of sediment samples collected from areas of known or suspected platinum and gold placers along the Bering Sea coast of Alaska. Results to date indicate that three geostatistical methods (subpopulation partitioning analysis, comparative factor analysis, and end-member compositional factor analysis) are useful in identifying elemental groups which can serve as "pathfinders" in the search for marine placers, and are also helpful in discerning the generic geochemical basis under lying observed statistical correlations between pathfinder elements and placer minerals. Existing methods of modelling sediment dispersal patterns have been examined with a view toward adapting them to the specific problem of understanding placer formation in

Jan 1, 1986