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By Julian Malnic

The emerging marine minerals exploration and mining industry is currently focused mainly on the technical elements for its success such as developing exploration and mining technologies. However, in one sense, the technical challenges are quite soluble whereas those arising in the fields of the environment and public opinion could present this new generation of miners with problems that are far more difficult to overcome. One need only look at the issues currently faced by mining projects on land to see how powerful the new forces of so-called ?civil society? are in stopping mineral developments in many countries. From the geographic viewpoint, there are many countries but there is just one ocean, so the impacts experienced by any one operation are likely to have pervasive repercussions throughout the industry. A well-oiled NGO development protest lobby will see leverage in resisting this new industry and will seize on the single-ocean angle. The Australian Minerals Industry has established a voluntary Code for Environmental Management that provides an active and valuable model for satisfying the ?court of public opinion? and in delivering economic results to industry that are in current jargon, sustainable. An explanation of the Code for Environmental Management, and the reasons behind 44 companies representing more than 300 operations and 85% of Australia?s sizeable mineral production being signatory to it will be given. Participants see it as a means to future shareholder wealth.

Jan 1, 2000

Welina mai to the 40th Underwater Mining Institute, UMI 2011 - Marine Minerals: Recent Innovations in Technology. Since the first conference in Milwaukee, Wisconsin in 1970, the UMI Founder Professor Robby Moore always insisted on actively seeking the participation of industry, academia, and government. History has proven the wisdom of this approach, which is probably the key to its survival for so many years. The UMI is very much influenced by the cyclical pressures of the minerals commodity markets. When minerals demand and prices are rising rapidly, industrial participation in the Institute dominates the agenda, and participants share optimistic and aggressive views of the commercial prospects of the day. When metals prices are falling and world economies lethargic, academic experts continue to provide guidance and breakthroughs in the concepts and practices of exploration, technology, and environmental protection. Throughout the ups and downs, government participants provide a stabilizing force with conservative and environmentally sensitive policy statements, patient development efforts with long-term objectives, authoritative resource assessments and, sometimes, much needed regulatory clarity.

Jan 1, 2011

By Andrea Koschinsky, Luise Heinrich, Stefan Gößling-Reisemann

"Germany, like several other countries, has entered a contract with the International Seabed Authority (ISA) to explore the prospects of commercial manganese nodule mining in the Clarion-Clipperton Zone (CCZ). Ensuring a maximally sustainable deep-sea mining operation requires a thorough understanding of the environmental impacts associated with every step of the mining process from the extraction of the nodules at the seafloor to the refinery on land. Against this background, the project presented here applies a combination of scenario-building and life cycle assessment (LCA) to assess and evaluate the sustainability performance of the individual process steps as well as the entire mining operation.Life cycle assessment (LCA) is a comprehensive methodological framework that allows the identification and quantification of impacts occurring during a products life-cycle, as well as the analysis and evaluation of their contribution to pre-defined impact categories, such as climate change, acidification and toxicity (Rebitzer et al., 2004). Until now, LCAs with a focus on raw material extraction have almost exclusively been applied to terrestrial processes. Noteworthy exceptions are offshore drilling, offshore wind farms and ocean fishing. Hence, the first part of the project is to investigate in how far LCA can be applied to deep-sea settings and if and in what way it could be adapted to be used in a deep-sea mining context."

Jan 1, 2017

By Richard T. Haworfh

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

Jan 1, 1996

By Henk van Muijen

From an interesting and intriguing scientific research topic, deep sea mining has altered into an interesting mining prospect over the last years. Ten years ago most of the focus was on geological investigations, searching for typical deep sea deposits and getting answers on where we can find them and how these deposits were formed. At this moment we know much more about the interesting deposit possibilities and with our quest for minerals, metals and other materials to feed global economic growth, answers as to the technical and economic feasibility to mine these deposits are sought. This is not a new phenomenon as we already witnessed such question late 1970?s and early 1980?s. Most of the focus was on mining manganese nodules and brines in the Red Sea driven by the report of the Club of Rome that predicted shortages in near future at that time. Development went different, but later in the 1990?s a rival of interest could be noticed for mining deep sea deposits.

Jan 1, 2010

By Francois P. Leroy

In the quest of studying the assigned blocks of seafloor for deep water mining, each member country of the ISA is thirsty for accurate information as to the level of resources available. Manganese nodules represent a large portion of the resources and are as precious as they are hard to locate and harvest. Resolving such challenges is what drives the technology development and yields instruments and products capable of serving this field of research. This presentation will study how manufactures of oceanographic instruments have pushed the technology envelop to in order to transform a collection of sensors and instruments into a seamless and adapted assembly working to serve the researcher and prospector in the challenging field they operate. Deep water data collection is characterized by the following challenges: ? Deployment, recovery and handling of the vehicle ? Producing high resolution at great distances ? Positioning that data with accuracy to relocate Teledyne Marine will present the work performed in its engineering laboratories to produce sub systems and systems now capable of delivering key information necessary to the proper cataloguing and exploitation of deep water mineral mining. Understanding and controlling the alternative resources available to each country will allow better management of current traditional land based minerals.

Jan 1, 2010

By Jan Magne Markussen

China, India and South Korea are three developing/newly industrialized countries that can show a very positive economic development in latter years. Moreover the three countries also feature amongst the countries with the highest level of activity in deep seabed mining today. India was the first country to achieve Pioneer Investor status in accordance with the UN Convention on the Law of the Sea. The country has carried out comprehensive exploitation of nodule deposits in the Central Indian Basin. India has an active programme for development of mining technology and internationally, India is probably the leading nation today as far as processing technology is concerned. China for its part has established a central coordination unit for its deep seabed involvement and its exploration and technology development is already well underway. South Korea has applied for Pioneer Investor status and much indicates that it will be allocated its own minesite in the autumn of 1994. The three countries are in mutual contact in the area of the Law of the Sea. Korea contacted both China and India when drawing up its application for pioneer investor status and allocation of minesite. However, no cooperation exists between the three regarding for example technology development, economic analysis or in studies of the environmental consequences. The main purpose of this paper is to focus on why and how the three countries would be well advised to cooperate in the above areas. Economic, technological and organizational aspects all point in that direction.

Jan 1, 1994

By Jon Machin

?ORE? is defined as ?mineral/s that can be mined at a profit?. So, what is ORE at 2,000 m water depth? Is it 5% Copper or 1.8% Nickel/Cobalt? One of the key factors that determine what is ORE, profitable or not, is the cost of mining and extraction. Therefore a determination of ORE requires a commercial and technical appreciation of both sea bed mining equipment and mining options. Perry Slingsby Systems (PSS) have built more remotely operated submarine work vehicles, including 900HP trenching machines, than any other company. With Nautilus Minerals, PSS have been studying a range of deep ocean mining solutions. This paper discusses the commercial and technical issues of various extraction techniques applicable to deep ocean mining from 1,500 m to 5,000 m water depth. Issues such as the rate of extraction, (i.e. tons per hour) is a key economic component and is often constrained by the design and horsepower of the miner. Likewise the design itself of the mining machine and cutting heads can determine the size of material produced which impacts on methods of lifting the ore to surface. Issues such as overburden, sea floor conditions, style of mineralization and physical properties of the ore, obviously affect the selection of appropriate mining machine configuration.

Jan 1, 2004

By P. C. Hollick

Two marine diamond deposits on concession 2b off Namaqualand along the South African Coast, have been systematically mined over the past year by the mv Moonstar. The two deposits, Smith?s Ulcer and Wedge Point Basin, are comparable in morphology, straddled the same water depths and have similar geology yet have given very different recoveries when compared to their respective grade models. These differences are best ascribed to the different style of mineralisation observed within the two deposits which has been directly controlled by the bedrock morphology. The smith?s Ulcer deposit has been formed in a metagreywacke bedrock displaying a strong north-south trending foliation which dips steeply to the west. Consequently the mineralisation is confined to narrow north-south linear trends with limited lateral extent (less than 5m) making extraction extremely difficult and somewhat variable. RE factors (recovered grade versus estimated grade) for this deposit range from 0.5 to 1.1. The Wedge Point Basin deposit is formed in a micaceous metaquartzite with a conjugate southwest northwest joint set, the southwest lineation being the more prominent, and structural foliation dipping gently to the west. The resultant style of mineralisation is confined to basinal features defined by topographical lows and is fairly lateral in extent (in order of 50m). Extraction of the mineralisation from this deposit is less arduous with recoveries more uniform, RE factors are frequently in the range 2 - 3. This style of mineralisation is more in line with what is to be expected from marine alluvial deposits, the nugget effect of diamond concentration being responsible for the high RE factor. The long narrow linear trends observed in Smith?s Ulcer demonstrably require a specialised approach in successfully sampling, modeling and ultimately mining.

Jan 1, 1998

By Samantha Smith

Nautilus Minerals (Nautilus) is following the lead of the petroleum industry as it strives to tap vast offshore resources. Planning is well underway for the Solwara 1 Project in the Bismarck Sea, Papua New Guinea (PNG) to recover high-grade seafloor massive sulphide deposits in 1600 m water depth. The deposit contains an average copper grade >10 times higher than a typical land-based porphyry copper mine. The high grades combined with a relatively small amount of overburden ensure the Solwara 1 Project will have a significantly smaller physical footprint than its land-based counterparts. Offshore minerals production also has the advantage of minimal social disturbance. Nautilus is dedicated to setting a high environmental and social responsibility standard. Nautilus recognises the importance of transparent and inclusive stakeholder engagement and has taken a proactive approach to involve as many key stakeholders as possible. One of the first steps in the permitting process in PNG is the preparation of the Environmental Inception Report, which describes the project, its envisaged impacts and the proposed studies for the Environmental Impact Assessment (EIA). Local (PNG-based) and international environmental scientists, anthropologists, NGOs and other experts were involved in the definition of studies conducted for the Solwara 1 EIA and a team of world-leading experts was involved with carrying out the studies, culminating in the preparation of the Environmental Impact Statement (EIS). To ensure transparency, collaborating researchers are free to publish their findings. Following its submission, the EIS was made available for public review and public hearings were held at several locations. The EIS has also undergone a rigorous independent review by PNG government-engaged consultants. Outside the permitting process, Nautilus works alongside government officials to carry out ongoing community consultations. Information dissemination and feedback acquisition has also occurred through the Nautilus website and attendance at a number of international conferences, workshops, and meetings. This paper will outline the leading edge approach Nautilus has taken in completing the environmental impact statement for the world?s first deep seafloor copper-gold mine. In addition, this paper will review the permitting process and the government and stakeholder engagement undertaken as part of Nautilus? desire to ?do it right? in this exciting new industry.

Jan 1, 2010

By Det Juridiske Fakultet, Maria Madalena das Neves

The ocean is increasingly seen as the answer for a myriad of challenges facing humankind. In effect, in addition to being vital for transportation and communication, the oceans contain living and non-living resources that are essential to meet the demand for food, and to the development of pharmaceutical products, energy resources, and high-technology products. This entails that the oceans are under pressure by different activities: navigation, fishing, oil and gas exploration and production, renewable energy development, laying of cables and pipelines, marine scientific research, bioprospecting, and deep-sea mining for minerals and metals. The growing demand for essential minerals and metals such as cobalt, nickel, zinc, copper, and manganese, seen in tandem with technological advances in deep-sea mining, makes the latter an increasingly attractive activity, both in areas within and beyond national jurisdiction. At the same time, the further development of deep-sea mining adds to the problem of the competing uses of maritime space and accentuates the need to balance and articulate the interests of the different users of the seas (States, sponsored deep-sea mining investors, oil and gas investors, fishermen, shippers, etc.). Furthermore, as deep-sea mining activities increase and move on to an exploitation phase so does the possibility of new disputes (for instance during deep-sea mining exploitation a communication’s cable is severed, a vessel conducting deep-sea bottom fisheries damages deep-sea mining equipment, etc.).

Jan 1, 2018

By Elisabetta Tedeschi, Razieh Nejati Fard

Deep-sea mining is in the future perspective of mining industry and it is currently in the technological development phase. The focus of this study is on the electrical power system that provides sufficient energy for the mining equipment at the seafloor, excavating Seafloor Massive Sulfide (SMS) deposits. SMS deposits usually exist at water depths between 1500 m and 4000 m. Despite the similarities of SMS deposits excavation to the open-pit terrestrial mines, more energy is required to drill and crush the ores in the hyperbaric conditions [1], which can be done whether by static trench cutters [1] or by mobile mining crawlers [2]. In addition, the ores vertical transportation by subsea pumps requires several MW electrical power that can be supplied by all-electric subsea motors or hydraulically from water injection motors located on the surface. The power requirements can be fulfilled by an offshore or subsea power network. As the SMS mines are usually in remote locations, the straightforward solution will be an isolated offshore grid mounted on a vessel or platform similar to the most of offshore Oil & Gas projects. These power systems resemble the onshore microgrids for industrial purposes operating in island mode. However, in contrast with the onshore power networks, there are space and weight limitations in offshore infrastructures, which impose the design compactness to be a priority. In addition, having a very high reliability is necessary in the design approach of the offshore projects due to the extraordinary high expenses corresponding to repair and maintenance. The other design criterion is to improve the power system efficiency in order to reduce the size of the power equipment cooling apparatus, operational costs and CO2 emissions produced by diesel/LNG onboard generators. There are a few studies considering power system distribution for seafloor mining industry. Among them, [3] has investigated the AC and DC alternatives for SMS mining in 2400 m water depth by considering Solwara 1 project scenario introduced by Nautilus Minerals Inc. [2]. In this study, a power system design tool will be presented taking into account various water depth, power consumption levels, different distribution configurations (AC and DC) and the aforementioned design criteria.

Jan 1, 2018

By Stephen J. Juras

The Myra Falls deposits comprise a complexly metal-zoned polymetallic volcanogenic massive sulfide district located 90 km from Campbell River in central Vancouver Island, British Columbia, Canada. The massive sulfide deposits are hosted by subaqueously-deposited rocks of the Devonian age Myra Formation of the Sicker Group volcanic assemblage. The deposits comprise many individual massive sulfide lenses grouped into several major zones within two main felsic volcanic stratigraphic intervals - the upper Lynx-Myra-Price Horizon and the lower H-W Horizon. The largest of these zones, the H-W and Battle, occur within the H-W Horizon. The first claims in the area of what is now Boliden-Westmin?s Myra Falls Operations were staked in 1917. Early prospecting resulted in the discovery of three massive sulfide showings which eventually became the Lynx, Myra and Price mines. Sporadic exploration was carried out until 1961 when Western Mines Ltd. (now Boliden-Westmin Ltd.) acquired the claims. Subsequent ore definition outlined 1.9 million tonnes of ore (approximately 5 years of mine life) in the Lynx deposit, and mining began in 1966. Pre-mining geological reserves (to January 1, 1997) comprised 6.7 million tonnes grading 3.3 g/t Au, 130.6 g/t Ag, 2.0 % Cu, 1.4 % Pb and 10.2 % Zn for the Lynx-Myra-Price deposits, 17.1 million tonnes grading 2.3 g/t Au, 32.7 g/t Ag, 2.3 % Cu, 0.3 % Pb and 4.2 % Zn for the H-W deposits and 4.2 million tonnes grading 1.1 g/t Au, 27.0 g/t Ag, 2.2 % Cu, 0.5 % Pb and 12.0 % Zn for the Battle deposits. Property-wide production to January, 1996 has been 15.7 million tonnes grading 2.1 g/t Au, 58.7 g/t Ag, 1.9 % Cu, and 5.2 % Zn.

Jan 1, 1998

By Raymond A. Binns

In this first sub-seafloor examination of an active hydrothermal system hosted by felsic volcanic rocks at a convergent plate margin, we drilled 13 holes altogether, achieving deep cored penetrations at two sites. Our aims were (1) to delineate the lateral and vertical variability in mineralisation and alteration patterns below the PACMANUS hydrothermal site near the 1650-1700 m-deep crest of Pual Ridge in the eastern Manus back-arc basin, so as to understand links between volcanological, structural and hydrothermal phenomena, and (2) to establish the nature and extent of microbial activity within the system. Technological innovations vital to success included our precise location of holes on small targets with drill-stem video, the use of a new hard-rock re-entry strategy, and deployment of casing with a new hammer drill. Other technical achievements were the first ODP application of an advanced diamond coring system, and the first direct comparison in a hardrock environment between structural images obtained by wireline methods and by logging-while-drilling (resistivity-at-bit).

Jan 1, 2002

By Sven Petersen, Berit Lehrmann, Bramley J. Murton, Paul A. J. Lusty

"INTRODUCTIONToday’s metal mining focusses on land based ore deposits which only consider one third of the Earth’s surface. Through an increasing global demand of strategic metals used in the electronic and green industry (Zepf et al. 2014), ‘uneconomic’ sites of lower grade in more technical challenging grounds such as greater depth and/or more remote areas are developed by the mining industry often resulting in higher environmental impact. However, considering the steady growth of the Earth population a shortage of certain metals may occur (Krausmann et al. 2009). In 2010, the United Nations allowed commercial exploration for seafloor massive sulphides (SMS) in international waters with currently six contractor licenses being granted.Although the number of discovered vent sites has steadily increased since the first discovery of hydrothermal venting at the Galapagos Rift in 1977 (Corliss et al. 1979) with more than 600 sites being known today, their economic potential is poorly constrained. So far Nautilus Minerals Inc., a Canadian mining company, is the only company having conducted a NI 43-101 resource estimate for the Solwara site, located in the territorial waters of Papua New Guinea. Other studies using bulk geochemical data from 95 sites published in literature do exist (Hannington et al. 2011, Monecke et al. 2016) suggesting a global resource potential for today’s known SMS deposits of 600 million tons with a median grade of 3 wt.-% copper, 9 wt.-% zinc, 2 g/t gold and 100 g/t silver. However, the geochemical data being used originated mainly from easily recoverable, mainly non insitu surface grab-samples and are under current mineral resource classification schemes such as JORC code or NI 43-101 not even accepted for resource estimations. Furthermore surface samples such as high-temperature sulphide chimney and talus material are not representative for the entire deposits with information regards thickness and continuity of individual sulphide layers obtained through drilling being scarce. In addition, it remains unknown what geological processes occur once hydrothermal activity ceases and whether metal tenor becomes enriched, depleted or disappears."

Jan 1, 2017

By Stephen Hall

Introduction Marine Autonomous Systems are making rapid progress from their early years as research tools for university departments & government institutes into having a growing number of real-world applications for industry, academia, statutory inspection, data acquisition and defence. Deep sea mining offers a distinct set of challenges that are very well suited to autonomous underwater vehicles (AUVs) and to a lesser extent for autonomous surface vehicles. Deeper, smarter, more capable Global demand for rare earth metals and high-grade ore will inevitably lead to exploitation of deep ocean resources as terrestrial reserves become depleted or remain unavailable for political or environmental reasons. Winning production licenses from the international seabed authority and especially gaining public trust to undertake deep sea mining activities and licenses will depend upon high quality pre-exploitation scientific surveys of the sea floor ecosystem, and subsequent monitoring of the impact of mining activity and remediation work. The actual area covered by the seabed mining operation may be quite small in terms of square kilometres, but still larger than can be patrolled by tethered ‘eyeball’ class Remote Operated Vehicles, so multi-spectral inspection, assessment and monitoring will be more effective when carried out by untethered AUVs. By using seabed recharging stations and data upload points the AUV can stay in situ in the deep ocean, rather than be repeatedly brought back to the surface.

Jan 1, 2018

By B. J. Bluck

Diamond mega-placers, in order to rank amongst the primary diamond deposits, are defined as => 70 m carats at =>95% gem quality. There is only one mega-placer known and that is found along the coast of southwestern Africa fringing the Kaapvaal craton. Placers are classified as residual when they are left on the craton, transient when being eroded into the exit drainage and terminal. Terminal placers, in being the final depositories of diamonds off the craton, have the greatest probability of being a mega-placer and such is the case in the placer deposits near the Orange River mouth, southwestern Africa. There are four main groups of conditions leading to the development of a mega-placer: the craton, the drainage, the nature of the environment at the terminus and the timing. The craton, in its role as the producer of diamonds is significant in respect to its size, diamond-fertility, the degree to which diamonds from successive kimberlite intrusions have been retained there and their availability to the final drainage yielding the mega-placer. Cratons in being buoyant have a tendency to leak diamonds into surrounding basins but in being incompressible often have orogens converge onto them resulting in lost sediment being returned as foreland basin fills. In order to concentrate a bulk of diamonds the drainage basin has to be large with a high proportion of it on the craton. The drainage yielding the mega-placer should ideally not have been preceded by older drainage and other systems that may have robbed the craton of earlier diamonds. The exits of diamonds from the craton need to be few in order to focus on their supply and the drainage network needs to be efficient in order to remove the maximum volume of diamonds off the craton. This efficiency and the focused termination is best achieved by the rejuvenation of a pre-existing drainage network. The drainage should be young enough to yield host sediments friable enough to allow brittle diamonds to be recovered from them.

Jan 1, 2004

By Harold Gibson, Ulrich Schwarz-Schampera, Ralf Freitag, Hendrik Mueller

INTRODUCTION Germany has a long history in marine research in the Indian Ocean. The first German scientific cruise started in 1964, followed by a series of state-sponsored research cruises between 1983 and 1995 leading to the first finding of polymetallic sulfides in the Indian Ocean. The research included regional bathymetric, geological, structural, volcanological, petrological and hydrothermal investigations along the Carlsberg Ridge and the Central Indian Ridge (CIR). Early environmental base line studies covered oceanographic and sedimentology aspects. In 2010, BGR took the initiative for the preparation of a license application for the exploration of polymetallic sulfides with the International Seabed Authority (ISA), and prospecting started in 2011 along the southern Central (CIR) and the northern Southeast Indian Ridge (SEIR) in the southwestern Indian Ocean (cruises INDEX 2011 on board R/V Sonne), INDEX 2012 (R/V Fugro Gauss), INDEX 2013/1-2 (R/V Sonne) and INDEX 2014 (R/V Pelagia). After three years of resource-oriented and environmental base line studies, BGR, in order for the Federal Ministry for Economic Affairs and Energy (BMWi), applied for an exploration license which was approved by and subsequently signed with the ISA in 2015. The license gave permission to start a detailed exclusive resource-oriented exploration program in the license area. The program includes the outline of potential ore deposits and a resource assessment but also extensive and detailed base line studies for the sustainable protection of the marine environment in the license area. The license contract has a fifteen years lifetime and may allow the application for a subsequent mining license. The exploration aims at the identification of inactive polymetallic sulfide deposits, formed below former discharge zones of hot hydrothermal fluids on the ocean floor (“black smoker” systems), by advanced and modern exploration techniques.

Jan 1, 2018

By Kira Mizell, James Hein

"INTRODUCTIONThe majority of studies on the genesis of ferromanganese crusts focus on the adsorption and accumulation of metals, and therefore cations, especially those of economic interest. From these studies, a first-order electrochemical model has been proposed based on the zero point of charge of the manganese and iron oxides at typical seawater pH, which assumes that positively charged ions will bind to the negatively charged manganese oxide phase and neutral and negatively charged ions will bind to the slightly positively charged iron oxide phase (e.g. Koschinsky and Halbach,1995; Hein et al., 2013). While the theory behind this model is sound, and it has been consistent for many elements, other elements may not follow the model (Koschinsky and Hein, 2003), and thus requires additional investigation and validation. As a new approach to understanding element accumulation in ferromanganese crusts and to test the proposed electrochemical model, this study investigates the surface chemistry of the halogens, which occur as negatively charged ions in seawater and have high and consistent concentrations in seawater.ResultsBulk Halogen ConcentrationsTo determine the distribution of halogens in ferromanganese crusts, an initial dataset of 24 FeMn crusts (24 bulk and 19 layer samples) from throughout the global ocean, including the Arctic and the Southern Oceans, has been analyzed for chlorine and fluorine content using ion-selective electrode. Although both Cl and F are conservative in seawater, their content in crusts shows striking variability (Cl: 326 - 13310 ppm; F: 146 – 1048 ppm for non-phosphatized crusts) and has no obvious geographic relationship to ocean basin and no correlation with water depth, latitude, or longitude. We plan to have bromine concentration data to present at the time of this conference."

Jan 1, 2017

By Gale L. Hubred

Kennecott?s Ledgemont Laboratory developed the Cuprion Process to recover metal values from manganese nodules in the early 1970s. A reducing leach of monovalent cuprous ion attacks the manganese oxide matrix, converting the manganese dioxide to manganese carbonate and releasing the copper, nickel, cobalt, and zinc as ammine complexes. Cuprous ion is generated by contacting leach liquor with carbon monoxide. Copper, and nickel, are recovered by solvent extraction and electrowinning. Cobalt is precipitated as cobalt sulfide and recovered as cobalt powder. Manganese, molybdenum, and zinc can be recovered optionally but have not been included in this process. Kennecott authors have described aspects of the process, but the Cuprion process has not been revealed except in patents. Tables are included for capital and operating costs and revenue. Even though economic recovery of nodules is not anticipated in the foreseeable future, some of the process steps may have application in other places. The Ledgemont Laboratory was a unique operation we think worth documenting. The report is based upon work done up until the mid 1970s. The report represents the work of the entire Kennecott nodule team. It is this author?s intention to save this result and credit the work of that nodule team. The paper is dedicated to the memory of Dr. Herbert Barner, a key member of the team who died in 2003.

Jan 1, 2005