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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 Michael R. Gipp

Marine Mining Inc. is currently exploring for marine alluvial gold and diamonds on a prospecting licence over a concession that covers 10,000 km2 of the continental shelf of Ghana. The boundaries of the concession extend from 0 30'W to 2 40'W, and between the shoreline and approximately the continental shelf edge north of 4 30'N. This concession extends from Kikam Beach in the west, to Senya Beraku in the east, a distance of approximately 240 km, and seaward an average of about 40 km. The concession is entirely underwater, with the exception of the estuaries of the Ankobra and Pra Rivers. Ghana has been a large source of alluvial gold, with historical production exceeding 25 million ounces. Southwestern Ghana is characterized by Precambrian rocks, which have been folded into a number of NE-SW trending synclines and anticlines. The most significant feature of the Birimian rocks is the presence of evenly spaced gold-bearing greenstone belts. They are 10-15 km wide, separated by about 90 km, separate basins filled by folded metasediments and granitoids. The rivers that enter the concession drain most of the exposed gold-bearing belts of Ghana. Given that approximately 2 km of erosion has taken place since the Mesozoic, and that gold mines on these belts boast proven reserves of over 55 million ounces, it is likely that large amounts of gold have been eroded out and carried to the sea. Coastal fractures, related to Precambrian structures reactivated during Mesozoic rifting, are responsible for the physiography of the coastal area, which consists of high-relief horsts separated by grabens that have been occupied and infilled by rivers or by finer sediments during times of elevated sea level. These fractures were loci of gold mineralization during the Precambrian, and are the source of alluvial gold in rivers confined by them.

Jan 1, 1998

By David Heydon

The big money is backing both manganese nodules and manganese crusts as the most likely deep ocean mining development by 2010, but seafloor massive sulphides of copper/gold/zinc offer an alternative bet for a start-up by 2010. A study of the ?form guide? or comparison of these resources provides direction on which resources are economic candidates for commercial deep ocean mining development by 2010. This paper covers the commercial and technical issues of exploration, resource definition, drilling/sampling, sea bed mining options, mine plans, environmental issues, legal tenure and capital and operating costs (i.e., profitability) of these two mineral types. Nautilus Minerals has just completed a pre-feasibility engineering study of mining sea floor massive copper/gold/zinc sulphides at 2,000 m depth. The Nautilus study reviewed a range of mining and lifting options, settling on tracked continuous drum cutter miners to produce 2 million tons per annum of high grade ore. Capital costs are shown to be at least 30% lower than a land based copper mine of the same production capacity. Likewise 75% of world?s copper would be produced at a higher operating cost that the proposed seafloor mine. This paper then draws on the Nautilus study for comparison with earlier feasibility studies by others on manganese nodule mining to predict the likely directions in deep ocean mining to 2010.

Jan 1, 2004

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 Mark D. Hannington

Seafloor polymetallic sulfides have been found in diverse volcanic and tectonic settings on the ocean floor at water depths ranging from 3700 meters to <1500 meters. More than 100 occurrences of hydrothermal mineralization have been documented (including Fe-oxide deposits, Mn-crusts, metalliferous sediments, and massive sulfides), but high-temperature hydrothermal activity and large accumulations of polymetallic sulfides are known at fewer than 20 different sites. Chemical analyses of samples from these deposits indicate that they contain important concentrations of Cu, Zn, Ag, and Au, comparable to those of massive sulfide deposits on land. However, the lack of sufficient data concerning the distribution, size, and bulk composition of seafloor deposits precludes a meaningful assessment of their resource potential.

Jan 1, 1994

By Richard H. T. Garnett

The first, profitable, marine placer mining started with tin 100 years ago but no major industry developed until the mid-20th. Century. Dredging at sea yielded cassiterite in both South Thailand and Indonesia, and remains an important state-run industry in the latter country. Malaysia and Russia have also contributed production, and the coastal waters of Tasmania and England have been explored. Marine placer deposits of gold have been examined in New Zealand, Chile, Argentina, Russia and West Africa. Philippino deposits were dredged during the 1930s. Fifty years later, at Nome in Alaska, gold was recovered by dredging from the offshore, and the technical/economic benefits of a seabed-deployed crawler were first demonstrated. Off the coast of Namibia placer diamonds were recovered by airlift mining during the 1960’s, but De Beers effectively started the existing marine diamond industry in 1989. The Wirth drill and a crawler continue to be used by the company, and plans recently have been announced for operations in South African waters. Other commodities such as mineral sands, platinum group minerals, and chromite have been investigated offshore in several worldwide localities.

Aug 24, 2006

By Tobias Hens, Andrew Frierdich, Joël Brugger

The rapid advancement of green technologies in recent years is closely tied to an ever- increasing demand for raw materials. Innovative forms of zero-emission transportation and sustainable power generation will require a variety of traditional metals such as Ni and Co, but also many non-traditional metals (e.g., REY). Many of these elements are known to be highly enriched in deep-sea ferromanganese (Fe-Mn) nodules and crusts. However, unlocking these metals from their deposits through metal processing is – aside from deposit exploration and production – expected to be a critical component that will affect the overall economics of the marine mining value chain. Hence, research and development of tailored metal processing solutions which can target specific metals of interest in Fe-Mn nodules and crusts, is required. Dynamic mineral recrystallization (DMR) of Fe-Mn oxide phases is a geochemical process that may have notable potential for hydrometallurgical applications. We have recently demonstrated that Ni can effectively be cycled between deep-sea Fe-Mn nodules and crusts and solutions through dynamic mineral recrystallization. DMR occurs in nature as abiotic background process during biogeochemical Mn cycling when dissolved Mn(II) is in direct contact with Mn oxides. Trace metals which are incorporated in the Mn host phases, are cycled between solid phase and solution via coupled dissolution (trace metal release) – reprecipitation (trace metal incorporation) mechanisms.

Jan 1, 2018

By Philomene Verlaan

This study examines the possible relationships between compositional variability in non-hydrothermal manganese nodules and large-scale environmental parameters. In the central SW Pacific (145-180° W and 20-O° S) the level of primary productivity, the rates and proportions of carbonate, silica and organic matter supply to the sediments, and the position of the seafloor relative to the Calcium Carbonate Compensation Depth (CCD) appear to directly influence nodule composition. Four zones of nodule composition are apparent. These zones correlate fairly well with the level of primary productivity in surface waters, as estimated by satellite-based measurement of chlorophyll content. The observed correlations between surface productivity and nodule composition are consistent with the contention that the dominant source of several transition metals in these deposits (i.e , Mn, Ni, Cu. and Zn) is provided by removal of fine-grained particulate matter from the water column by biological means. Subsequent decay of organic matter in sediments augments the content of these metals in the nodules through oxic and sub-oxic diagenesis. The opposite behavior of Fe and Co content may in part result from mineralogical and dilution effects.

Jan 1, 2000

By Tobias Hens, Andrew Frierdich, Barbara Etschmann, Joël Brugger, Barrie Bolton

"Advancing our knowledge about trace metal distribution and abundance provides insight into formation, alteration, and trace element enrichment processes of ferromanganese nodules and crusts. A fundamental understanding of these mechanisms, in turn, has implications for the selective recovery of critical metals and the development of sustainable hydrometallurgical techniques. Synchrotron-based X-ray Fluorescence (SXRF) is a powerful, state-of-the-art analytical tool that can examine geochemical features of Fe-Mn nodules and crusts, such as abundance and distribution of trace elements, in an integrated and efficient manner. By correlating trace element composition and Mn oxidation states in these highly complex samples, it can be determined whether these parameters are related to the Mn oxide mineralogy (vacancy content of crystal lattice) and chemistry.In this study, eleven Fe-Mn nodule and crust samples from three circum-Australian locations – the South Tasman Rise, Lord Howe Rise, and Coral Sea – were analyzed at the Australian Synchrotron, Victoria, Australia. Micrometer-scale spatial resolution of geochemical features, such as concentric growth structures and element distribution, was achieved with high sensitivity (Fig. 1). For instance, Ni could be detected at 10's of ppm to 1 wt% levels. Information on other redox-sensitive trace elements, which are present at 10-1000 ppm levels (e.g., Cu, Co, Ti), were gained by means of fully quantitative elemental composition maps."

Jan 1, 2017

By Porter Hoagland

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

Jan 1, 1996

By Georgy Cherkashov, Livia Ermakova

Active development of the exploration and further exploitation of deep-sea minerals requires special emphasis on the protection of the marine environment. The complexity of this subject lies in the fact that potential impact and effects of future mining activity are not completely known. One of the main sources of potential impact near the seafloor, as it expected, would be a generation of sediment plumes, their dispersion and redeposition of sediment. Meanwhile, their dimensions, rates of dispersion and redeposition are a big issue. Other plumes are expected in the surface layer as a result of discharges of processing waters and particles after sorting on board of mining vessel, and their features are also not clear. At the same time, understanding of these aspects would be crucial for definition of environment impact area, delineation and designation of different types of protected areas (Areas of Particular Environmental Interest, Impact and Preservation Reference Zones) and future assessment of environmental impacts. Attempts to address these issues demonstrated wide variations between the data of field experiments on the one hand and the results of analytical and numerical models on the other. According to in situ measurements, plumes were detected at a distance vary from one to less than 20 km [e.g., Burns et al., 1980; Sharma et al., 2001; Nautilus Minerals, 2008 etc.], whilst some models show results up to 100 km [Rolinski S. et al., 2001] and more. It seemed that results of in-situ experiments are preferable, but they were not many indeed. However, these data were used in different investigations rather widely, but their focus, as far as we know, was not on the matters related directly with plumes.

Jan 1, 2018

By Thomas Pichler

In the past marine mining technology has focused on bulk mining of base metals from polymetallic massive sulfides. This has not been very successful because of the relatively low unit value of these metals and other reasons such as water depth, etc.. The process of gold enrichment in hydrothermal deposits is controlled through five different factors: (1) nature and source of the solution, (2) source of the gold, (3) a mechanism for mobilizing and transporting, (4) a mechanism for deposition, and (5) a mechanism to preserve the deposit. Gold has been identified in marine polymetallic massive sulfides from various locations on the ocean floor (e.g., spreading centers, seamounts) with contents ranging up to 5 ppm Au. This is within the current range of 1.0 to 7.0 ppm gold content which classifies gold ores. The gold appears to have been derived during hydrothermal alteration of the oceanic crust. Until the present there has been little attention to the possibility of mining gold or other precious metals in the marine environment. However, the magnitude of hydrothermal alteration (seawater can penetrates to a depth of 5 km into the oceanic crust) and primary gold contents of the rocks in the pathway of the fluid indicates that major gold deposits must have formed on or in the ocean floor, but they have not been found. To find a big deposit might only take an exploration model exclusively designed for gold exploration on the ocean floor.

Jan 1, 1993

By D. S. Cronan

Pitcairn Island, the last remaining British Colony in the Pacific Ocean, falls in the S.E. Pacific. Its location, on top of a hotspot volcano, suggests the presence of submarine hydrothermal deposits in its EEZ. Such environments are known to contain hydrothermal mineral deposits, as in the case of Loihi submarine volcano near Hawaii, and Macdonald and Teahitia-Mehitia seamounts in the South Pacific. The hydrothermal deposits in these areas are formed as a result of the interaction of seawater with hot volcanic rock, producing a hydrothermal fractionation sequence comprising sulphides of Fe, Cu and Zn, oxides and silicates of Fe and oxides of Mn. In 1988, a GLORIA survey from the RRS Charles Darwin confirmed the existence of recent volcanism within the Pitcairn Island EEZ. A later bathymetric and sampling survey by the FS Sonne of the region round Pitcaim Island revealed submarine volcanoes approximately 80 km ESE of the island. Hydrothermal mineral deposits were recovered from them, and comprise finely laminated crusts of Fe oxides containing up to 50% Fe, and laminated hydrothermal Mn crusts up to 5 cm thick. Both morphologically and chemically the latter are similar to those from mid-ocean ridge and island arc settings, containing up to 50% Mn, associated with sulphides, and represent first discovery of such deposits associated with mid-plate "hotspot" volcanoes. Massive sulphide deposits are thought to occur within the volcanic pile.

Jan 1, 1992

Recent focus by terrestrial mineral explorers (and investors) on cobalt has increasingly highlighted the future critical need for this metal, with new-age batteries being the primary utilisation. We present an overview of the world’s current terrestrial cobalt resources and put this in perspective of currently known seabed resources, particularly polymetallic nodule and crust deposits. We focus on comparison of the key exploration, development and exploitation risks for such deposits, and provide a framework for financial evaluation and appraisal.

Jan 1, 2018

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 David M. Holmes-Smith

Many attempts have been made to design and build an AUV that is small, meets the sensing objectives and is cost effective. Many inventors have already designed smaller vehicles but the problem observed is an increased vehicle instability resulting in instrument instability where data gathered is not trustworthy. Additional problems include instrument weight to vehicle weight ratios and the lack of space for power storage and electrical components. The UFOceanic seeks to remedy these concerns by employing a completely different design and propulsion system. Still in the design stage ? now with a mock-up unit for testing, the results are encouraging. We have chosen a very low voltage embedded systems design using multiple PIC processors and fuzzy logic programming. We are designing the craft to rotate for stability and to provide friction reduction to minimize the need for instrument stability compensation and propulsion power. Additionally, we are looking and experimenting with a number of power plant drive systems including flywheels, GNP (plasma), fuel cells and more conventional systems. We of course plan for the UFOceanic to run for months at a time supported by a self-charging system.

Jan 1, 2001

By Chris Roper

The Gavia Autonomous Underwater Vehicle is a two-man portable AUV that is capable of performing seafloor surveys in water depths to 2000 meters. The standard survey sensor suite includes a dual frequency side scan sonar and high resolution digital camera. Additional survey sensors are currently being incorporated into the Gavia AUV, include Sub Bottom sonar, Swath Bathymetry sonar and Multi Beam sonar. The modular design of the Gavia AUV allows the end user to quickly incorporate new sensors including client developed propriety sensors.

Jan 1, 2005

By Christina Pomee, John Parianos

"TOML’s ISA Contract comprises six areas (A-F) that span from 118° to 152° W and from 7° to 15° N or over 70% of the CCZ.During a 2015 exploration cruise, TOML scientists found that the a logging system developed by ISA (2010) was able to be adapted and enhanced, to describe in some detail the varied morphology of nodules both within the TOML areas and between them.The shapes and sizes of nodules seen were then found to relate to substrate type and setting, and thus likely thickness and long-term stability of the geochemically active layer. Consideration of the various processes that might influence growth helps constrain nodule formation further. The nodules effectively record the long-term geochemical conditions that lead to their formation.ISA (International Seabed Authority), 2010. A Geological Model of Polymetallic Nodule Deposits in the Clarion-Clipperton Fracture Zone and Prospector’s Guide for Polymetallic Nodule Deposits in the Clarion-Clipperton Fracture Zone. International Seabed Authority Technical Study: No. 6 ISBN: 978-976-95268-2-2"

Jan 1, 2017

By Lisa Koch, Eleanor Martin

"Each underwater mining project is different. However, most have one thing in common: To be successful. We will draw on our experience advising hundreds of international clients each year on mining, offshore oil & gas and shipping matters to highlight some legal, commercial and practical issues to consider when structuring underwater mining projects. We will look at new ways of allocating risks and rewards in order to obtain much needed investment for underwater mining projects to commence both the exploration and exploitation phase.HighlightsRisk profileWe will look at a typical underwater mining project from the viewpoint of an investor and highlight some of the perceived risks, and potential mitigants.Contractual structureWe will analyse how the mining industry and oil & gas service industry have responded to low commodity prices to examine innovate contractual arrangements with suppliers and stakeholders, and how they can be tailored to the underwater mining industry. FinancingWe will explore some potential financing structures which could be relevant to the underwater mining industry."

Jan 1, 2017

By Joshua Brien

DEEP SEABED MINING IN NATIONAL JURISDICTION: KEY CHALLENGES The talk focuses on the key challenges that arise from deep-seabed mineral exploration and development within areas of national jurisdiction, including legal and institutional challenge and options to address these challenges. Joshua Brien has acted for a range of Governments throughout the world, including smallisland States and the developing world. This has included engagement in matters before the International Court of Justice, the Tribunal for the Law of the Sea in contentious and advisory proceedings, including provisional measures applications and prompt release cases.

Jan 1, 2018