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By Leonhard Weixler, Peter Platzek

The Company Bauer Maschinen is very well known in the field of specialist foundation equipment. In the diaphragm wall market, we have experiences both in manufacturing and executing projects all over the world since 1984. We have a population of more than 300 units working all over the world in all climate and soil conditions. Especially for hard soil and rock conditions, we have developed several cutting tools and systems to optimize the performance, e. g. the “flipper tooth” Besides the execution of land based foundation projects, we have performed our firs offshore project with the trench cutter in 1994. Our task was to take samples out of the alluvial soil off the coast of Namibia in a water depth of max. 200 m. We converted a drill vessel and launched the cutter thru the moon pool. The samples had a cross section of 3,40 m² and a max. depth of 5 m. They were used to estimate the content of diamonds. The first time, we reached the seabed of the deep sea was together with our seafloor exploration rig MeBo, where we can take cores up to a length of 160 m in a maximum water depth of 4000 m. With our customer MARUM, we have done several expeditions since 2005. The last expedition took place in the Black Sea to explore gas hydrates.

Jan 1, 2018

By W. C. Burnett

The land phosphate deposits of the U.S. southeastern coastal plain have long been a major factor in the world trade of phosphate rock (Fig. 1). As recently as 1979, deposits of North Carolina and Florida alone accounted for about 33 percent of the entire world's phosphate exports. This situation is changing, however. World production increased by ~9 %, yet the U.S. share was down to ~28% in 1984. A complex interaction of economic and political factors combined with increasing costs of raw materials, production, and transportation have led to this systematic erosion of the U.S. market share. Changing land-use patterns within the southeast, environmental pressures, exhaustion of shallow high-grade resources in Central Florida, and the increased pressure from expanding low-cost production in other countries throughout the world account for much of the present difficulty in the U.S. phosphate industry. Considering this depressed environment -- what are the prospects for development of offshore resources? A summary of new research on offshore phosphorite within the U.S. Exclusive Economic. Zone (EEZ), as well as an attempt to place possible development of these resources within the current economic setting, is the purpose of this presentation. We will emphasize work in progress on a major offshore deposit along the U.S. Atlantic Margin as well as new research on Pacific Ocean occurrences of phosphorite on seamounts and insular slopes within U.S. waters.

Jan 1, 1986

By G. A. Gross

Technological development in the last two decades has provided access to the deep seabed and opened a new frontier for exploration. Interest in Canada has focused mainly on study of metallic mineral occurrences and the development of a scientific data base and technology for identification and appraisal of potential mineral resources. Canadian industry and government have played an active part in the assessment of manganese nodule resource potential and the possible impact that development of these resources might have in the world mineral markets.

Jan 1, 1985

By Christian Müller, Hermann-Rudolf Kudrass, Christian Reichert

Recent studies estimate the depletion mid-point (dmp) for conventional natural gas to be reached around year 2022, and for conventional oil to be reached around year 2017. These numbers are based on simplified assumptions of unchanged demand and do not include increasing reserves from discovery of new fields and also do not include a shifting of resources to reserves e.g. due to an increasing oil price (Gerling et al., 2005). Anyhow, these prospects require conventional hydrocarbons to be substituted in the near future.

Aug 24, 2006

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 Steven D. Scott

The 1991 PACMANUS Expedition (Papua New Guinea-Australia-Canada in the Manus Basin) discovered a very large (approximately 800 x 350 m) actively-forming seafloor polymetallic sulfide 4 deposit in felsic volcanic rocks of the southeastern part of Manus Basin, a 60 km wide extensional zone of basalt, andesite and dacite volcanism in the New Britain back arc. The apparent neo-volcanic zone is a 30-km long, high standing, Y-shaped edifice, which we have named Pual Ridge ("Pual" means "fork" in a local PNG dialect). The PACMANUS deposit was found by deep-tow video on Pual Ridge along the flank and adjacent valley of a dacite lava dome. Videos show large spires, chimneys and mounds with abundant fauna. Only two small samples from an active chimney were recovered. Their mineralogy is a high temperature assemblage of chalcopyrite, bornite, tennantite, sphalerite or wurtzite and anhydrite. The bornite and tennantite and silver rich. Gold values for the two samples are 2 and 10 ppm. A pronounced methane and particulate plume was traced in the water column for 14 km to the northeast of the PACMANUS deposit. Other deposits of unknown size are nearby. The deposits of Pual Ridge and their surrounding volcanic rocks have close similarities to ancient massive sulfides of Archean to Phanerozoic age in Canada and Australia.

Jan 1, 2011

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 Hans Smit

The face of mining as we know is changing as mining companies all over the globe realize the reality of accessing the vast mineral wealth contained on, and under, our ocean floors. With some land based mineral deposits being fully exploited across the world, deep sea mining is set to revolutionize global approaches to the search for precious metals and other sought after minerals. Previously, the financial and technological implications of deep sea mining outweighed the benefits of access to the mineral rich deposits identified all around the world. The process of marine diamond mining off the west coast of southern Africa started in the late 1950s, and subsequently continued by De Beers to the present day, has proven to be an excellent proving ground for the development of technology and mining systems that ensure a sustainable and financially viable business.

Jan 1, 2011

By Alexey Musatov, Georgy Cherkashov

Based on geochronological data it was confirmed that hydrothermal discharge has an episodic character: active and inactive periods of the seafloor massive sulfides (SMS) formation alternate (Cherkashov et al., 2017). There is an assumption of correlation of the periods of magmatic and hydrothermal activity with the stages of glaciation (Lund et al., 2016). During the cold periods, the level of the ocean was reduced from 70 to 150 m depending on the glaciation scale (Spratt, Lisiecki, 2016). As a result, the hydrospheric pressure on the upper mantle decreased and could provide increased magmatic and hydrothermal activity (Lund, Asimow, 2011). This assumption is confirmed by the correlation of warming and cooling stages with increasing of hydrothermal input to the bottom sediment near hydrothermal fields. According to data (Lund et al., 2014, 2016; Middleton et al., 2015) the peaks of hydrothermal activity, expressed in the layers of metalliferous sediments at the East Pacific Rise and the Mid-Atlantic Ridge, roughly correspond to the last two periods of cooling (20 and 60 ka). To test this hypothesis, we tried to compare the sequence of warm and cold periods in the Pleistocene with the dating of SMS reflecting the periods of hydrothermal activity. Results SMS samples were obtained from 12 sites within the Russian Exploration Area at the MAR segment 12-20°N. The results of dating 198 samples by the 230Th/U method demonstrated the absence of correlation between hydrothermal activity periods in different hydrothermal fields (Cherkashov et al., 2017). It was proposed that each field has its own evolutions scenario. Considering this point, only the oldest SMS dating for each field which fixed the beginning of hydrothermal activity was selected for comparison with the cold/warming periods.

Jan 1, 2018

By Valcana Stoyanova

Data and information for this study were collected in June-July 2009 onboard the RV Yuzhmorgeologiya in the area covers about 7000 km2 in the eastern part of the CCFZ between 10º05? - 10º55?N and 119º25? ? 121º08?W. In accordance with the IOM research program the cruise was intend to acquire both geological and environmental data and information necessary for delineation of nodule deposits and also data for identification of the baseline of benthic ecosystem. Having implementation of its 15-year plan of work for exploration under the contract with ISA, current activities of IOM were focused on nodule fields within prime areas that could be mined in the future. Bottom photographs obtained by towed deep-sea vehicle NEPTUN along 6 profiles with common length about 300 km (Fig. 1). In total, about 11,500 digital photographs (what cover approximately 40,000 m2 of the ocean floor) were analyzed for assessment of nodule coverage and investigation of megafauna (animals, visible in photographs, the dimension more than 2 cm). The giant single-cell organisms Xenophyophorida were the most multiple animals in seabed photographs. Their number on the site area averaged 1187 ind/ha. However, the vertical camera position does not allow counting all xenophyophorids, therefore their valid number is represented 10 times more. According to all available information these protozoans play the relevant role in assemblage of deep-water environment, giving for other animal groups an [ ] additional source of nutrition and a substratum for settlement and attachment. The ophiuroids are found in assemblage with xenophyophorids in many cases, standing on a sediment at their base.

Jan 1, 2010

By Maria Thornhill, Rolf Arne Kleiv

INTRODUCTION The last decade has given rise to an increasing number of deep-sea mining concepts (DSMCs) outlining technical solutions for the production chain from seafloor mining to mineral or metal extraction. The vast technological and logistical challenges coupled with immature but rapidly evolving technology has spawned a great variety in proposed concepts, and the exact implications of the phrase ‘best available technology’ is very much an open question. DSMCs differ significantly with respect to choice of technology, technological readiness level, degree of resource utilization, logistics, OPEX and CAPEX requirements, overall profitability, legal and political implications, not to mention environmental impact. Hence, a system for classifying concepts could provide a useful identification and structuring tool when performing economic, judicial or environmental assessments of DSMCs, as well as offering a general terminology to describe concepts sharing fundamental traits. This abstract proposes a DSMC classification system based on how a concept makes use of mineral separation at the different stages in the ore’s journey from the deposit to the ocean surface and ultimately to onshore facilities. Mineral separation, as a process step, is the key factor in determining both the state and mass flow of materials along the production chain and has, as such, a decisive effect on economy and environmental impact of any deep-sea mining project. A DSMC that is based on bringing the entire volume of broken ore to onshore facilities for processing will look very different from a concept based on pre-concentration (i.e. mineral separation) at the seafloor. Whereas the latter offers savings in the form of reduced energy cost for vertical transport, it also represents a substantial additional technological challenge. Furthermore, whether or not a concept relies on mineral processing at the seafloor or on a floating facility at the ocean surface above the deposit also determines the point at which mineral separation waste (i.e. tailings) must be managed. Different concepts offer different opportunities for tailings deposition, and are at the same time bound by different requirements.

Jan 1, 2018

By Robert G. Ditchburn

Dating seafloor mineralization at hydrothermal centres of submarine arc volcanoes is important for understanding deep-seated volcanic events that can produce deposits rich in base and precious metals. The activity ratios, 228Th/228Ra, 228Ra/226Ra (Bq.Bq-1) and 226Ra/Ba values (Bq.g-1) are used for dating barite- rich seafloor massive sulphide (SMS) in the age ranges 0.3 ? 12 years, 3 ? 35 years and 500 ? 15,000 years, respectively. Thus, the time elapsed to amass an economic deposit and, ultimately, its capacity for sustainable extraction, can be estimated. 226Ra/Ba and 228Ra/226Ra values have been measured in relatively young chimneys that were collected, 1998 to 2006, from hydrothermal sites at Brothers and Clark volcanoes (Kermadec arc) and East Diamante volcano (Mariana arc) to check these initial ratios, essential for calculating ages for older mineralization at the same sites, were not varying significantly. We found that the 226Ra/Ba value for fresh SMS mineralization at the Brothers NW caldera and East Diamante hydrothermal sites have been reasonably stable for 6 years and 2 years, respectively. At both sites, the 228Ra/226Ra value for fresh SMS has been stable for 5 years. This was established from young chimneys where the measured 228Ra/226Ra value could be corrected for radioactive decay using the age derived via the 228Th/228Ra method. However, long-term stability of the initial 226Ra/Ba and 228Ra/226Ra values has yet to be proven. These isotopes of Ra are used as a proxy for better understanding of the transfer of Ba from deep magmas to the seafloor, via the circulating fluids of the hydrothermal system.

Jan 1, 2011

By Derek Ellis

There are two environmental issues which have only recently begun to need planning in detail for marine mining. One is the environmental consequences of mine closure; the other is environmental terrorism. In principle it is not difficult to predict the pattern and rate of biodiversity recovery after mine closure on metalliferous depositional seabeds. 1-5 years to a self-sustaining community of organisms is a generalized guideline, depending on depth and particulate composition. The rate and pattern of biodiversity recovery on some metalliferous hard-rock habitats is far less predictable due to the patchiness and rareness of the habitat. Ecoterrorism at mines, whether on-land or marine, is now to be expected. A good example of resource industry ecoterrorism is the fire-bombing of logging and cement trucks in Oregon in 2001. But there have also been bombs at mine sites, as at Asbestos, Quebec. It is also possible to regard some resource-loss lawsuits as frivolous, hence forms of ecoharassment. Marine mining operations should take note of the development of environmental terrorism (and terrorism in general) and its various manifestations and impacts. Potentially these range from minor work stoppage inconveniences, to serious financial risk jeopardizing the economics of a mine, to jail for company executives, managers and environmental staff, and to harassment and killing of mine personnel.

Jan 1, 2005

By Keith Gordon

The recent discoveries of hydrothermal activity in the ocean off New Zealand have created interest in the business community in the commercial possibilities of mining associated marine polymetallic sulfides. This interest is more so, as this hydrothermal activity is in much shallower depths, between 120 ? 1800 meters, than the typical 2400m in other parts of the oceans. Mining for other ocean deposits around NZ, such as phosphate nodules and off-shore deposits from gold bearing river beds is also attracting interest. The question is: - how can these deposits be mined without spending the enormous sums of money required for specialized mining technology? There are no dedicated off- the-shelf systems designed exclusively for underwater mining. Such systems require expensive development and manufacturing processes and then, are most probably designed for only one specific purpose. The costs involved place such equipment beyond the means of smaller entrepreneurial groups and only the big companies have the resources required. However, large companies are normally reluctant to take the risk of investing large sums of money into deep ocean projects. Australia and New Zealand, until recent times, have been somewhat isolated from European and North American technical resources - especially in the field of underwater technology. Over the past century such isolation has often led to solving problems with what has become locally known as ? ?the number 8 gauge wire method?. This approach to problem solving entails using whatever is available to get the job done and keep costs down. In the old days with NZ technology being mainly based around farming, a piece of No. 8 gauge fencing wire, although not designed for the purpose, was often used to fix various problems ? hence the term.

Jan 1, 2002

By Igor E. Mikhaltsev

This paper concerns the continuation of work on the deepwater non-oxygen cycle heat energy generating systems. The 25-kW prototype of a universal deepwater turbine-electric energy source with hydrazine-hydrate as the primary heat production chemical is described in short and its abilities are discussed. The ?hydrazine-hydrate 64? is a catalytically dissociated heat production chemical (H2H4 ? nH2O) with 36% of water. The system was designed for work in any depths of the ocean down to 6000 m. It was built and tested working in the testing chamber in the ambient hydrostatic pressure of 600 bar. Then it was tested in the autonomous programmed regime in the Atlantic Ocean. The privileges of that energy system for any bottom installations or moving devices designed for ocean mining which need high power energy sources (20-100 kW and more) are discussed. The important needed step forward is raising the efficiency of the system which needs some investigation work in known directions. It is supposed that the possibility of getting about 5 kg/kWh with improved battery charging possibilities could be achieved. This might make the system even more profitable for mining operations.

Jan 1, 2001

By Pedro Madureira, Georgy Cherkashov, Harald Brekke, Marzia Rovere

"The most promising deep-sea mineral resources for exploration in the Area (beyond the limits of national jurisdiction) are polymetallic nodules, cobalt-rich ferromanganese crusts and polymetallic sulphides. These marine minerals have different characteristics in their distribution, geological setting, grades of metals and genesis. Considering future exploitation of nodules, crusts and sulphides such parameters as estimated resources, specific mining operations and ore processing are different as well.Comparative analyses of deep-sea mineral minerals as well as onshore and offshore resources will be discussed in the paper."

Jan 1, 2017

By Cheong-Kee Park

Since 1983, Korea Ocean Research and Development Institute (KORDI) have performed surveys on deep-sea mineral deposits in various areas with respects to their occurrences in Pacific ocean including manganese nodules in the C-C area of Northeast Pacific, Co-rich manganese crusts in various seamounts of West Pacific and hydrothermal sulfide deposits in back arc basins of Southwest Pacific. Among the results of these activities of KORDI, remarkable things were the registration as a pioneer investor in 1994 through the Government of Korea and the accomplishment of relinquishment on the allocated area in 2002 according to the relevant regulations. KORDI is faced to handle detailed surveys to select the optimum mining sites in the allocated area of 75,000 km2 and environmental studies to meet the requirements of the regulations or recommendations of the ISA. In respects of future exploration strategies, it is considered that methods and tools of previous exploration activities should be changed to the highly advanced technology. Establishment of an advanced exploration system and actual practice in appropriate areas become one of important tasks of KORDI in exploring deep-sea minerals, particularly manganese nodules. A technical strategy for future detailed surveys in the allocated area is realization of simultaneous and precise data acquisition on bottom information, such as variations of microtopography, nodule distribution, and transparent layer thickness of sediments in relatively small area (10 km x 10 km) representing certain specific regions, by high resolution survey technology. It would be not only a challenge for new exploration system in deep-sea environment, but also a mission for deep seabed mining venture.

Jan 1, 2003

By David Gwyther

There is increasing recognition that in order for a development project to proceed successfully, it must first obtain a ?social licence to operate? from concerned stakeholders. Obtaining this ?licence? is in many ways a separate process to the legal one which involves, among other things, submitting an environmental and social impact assessment (ESIA) to the appropriate regulatory authority for review. Essentially, the function of an ESIA is to present a project?s technical, financial and social benefits, together with its environmental and social impacts in a transparent way to enable regulators to make an informed decision about whether the benefits outweigh the impacts, and thus whether or not the proposed project should proceed. The focus in the early days of ESIAs was primarily technical and was aimed to answer two fundamental questions: ?Can the project be built?? and ?Can we minimise impacts to a level that is acceptable to the community?? Basically, the ESIA process was a technical test of competence, but more recently, ESIAs have become much more than this. The main ESIA risk is now more akin to a test of a project?s legitimacy ? i.e., with more weight placed on the social licence, or the political test of moral authority ? with the process involving stakeholders from multiple backgrounds and disciplines, including some anti-development NGOs/civil society groups with their views on mining, (particularly in developing nations), often already pre-determined. Within the backdrop of this potential maelstrom, now enter a proposal for a new industry (such as deep sea mineral extraction).

Jan 1, 2011

By Eleanor Martin

An examination of the draft Exploitation Regulations from an investor’s perspective. We will look at the commercial requirements of the investment community (debt and equity) in order to provide funding to a deepsea mining project, and contrast this with the position put forward in the draft Exploitation Regulations. We will then recommend suggested amendments to the Exploitation Regulations to assist future investment on this growing industry.

Jan 1, 2018

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