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By S. C. W. de Jong, E. de Hoog, J. M. van Wijk, S. J. Dasselaar

Introduction Technology development for sustainable, safe, reliable and efficient mining of polymetallic nodules in the deep seas requires careful design, thorough understanding and integrated testing of all equipment, physical processes and (sub) systems involved (Dasselaar et al [1]). Proceeding from Vertical Transport System (VTS) experiments at IHC laboratory scale by Van Wijk [2], with typical system dimensions of several meters, to prototype or pilot scale testing with typical dimensions of several kilometers, is a giant leap. Naturally, intermediate steps are required in order to mitigate the possible risks in the full-scale system’s (physical) processes. Within the EU program Blue Mining (2014-2018), possibilities emerged for performing experiments at intermediate scale: the so-called medium-scale vertical slurry experiments. Near Freiberg, Germany, the village Halsbrücke possesses a 140 meter deep empty vertical mine shaft, perfectly suited for housing the test setup. For this purpose, a 318 meter long 145 mm pipeline circuit was constructed, including both a 130 meter high vertical riser and fall pipe section. A purpose-built sediment injection and separation system was deployed, including a 55 kW centrifugal pump. The riser section has been equipped with sensors capturing pressure, temperature, flow velocity, volumetric concentration and flow visualization. The planning, modification and construction of the test facility site itself is described by Müller et al [3]. The present paper describes the objectives, experimental program, equipment, and the preliminary results. Publications on in-depth results are foreseen in the (near) future.

Jan 1, 2018

By Pia-Maria Haselberger, Marc Schiemann, Christian Frühling, Nicolas Richter, Hendrik Wehner, Andreas Kaschube

"The paper provides the principle considerations for a novel vehicle class within the scope of the project Large Modifiable Underwater Mothership (MUM). The main idea for these ships is to create a highly modular building block system for the global layout. This building block system allows for a mission-dependent module assembly. For the purpose of deep sea mining for example, the range of tasks reaches from multipurpose transportation and exploration missions to supporting tasks in up to 5000 m depth, e.g. energy supply. Topics covered in this paper are related to potential missions for these vehicles, the modular layout and the structural layout of a separate block module. The paper closes with a conceptual design example for this class.Index Terms—MUM, UUV, underwater mother ship, autonomous underwater vehicle, modular, deep sea, conceptual designI. INTRODUCTIONAs one of the leading economic nations, Germany is in need of energy and raw materials. In the 21st century, marine resources are a prominent and promising alternative to land based resources. However, there are challenges that need to be considered. Rough and often poorly plannable weather conditions prevail distant to the marginal seas. Ice coverage makes offshore services inefficient and costly in Polar Regions. The average ocean depth of 3500m and the associated environment conditions cause difficulties in fulfilling tasks in the deep sea. The project Large Modifiable Underwater Mothership (MUM) [1] will enable more efficient solutions in order to accomplish undersea duties and services in harsh conditions.This joint project comprises workshares from Atlas Elektronik, EvoLogics, thyssenkrupp Marine Systems, the University of Rostock and the Technische Universität Berlin. The principle idea of the project is the conception of a novel vehicle class. With highly modular autonomous underwater vehicles, this class will be capable of undertaking a variety of different tasks. Classically engineered vehicle structures will be split into single basis modules which can be flexibly assembled with specialized mission modules to form potent systems for individual assignments. The group of basis modules consists of units for navigation, vehicle control, propulsion and energy generation via fuel cell technology. The potential reusability of system relevant modules leads to a significant cost reduction and to shortened development periods compared with conventional vehicle concepts. The integration of newly designed additional mission modules is possible with little effort and a separate commercialization of single modules is feasible."

Jan 1, 2017

By A. A. Schipaanboord, S. J. Dasselaar

"With the growing global demand for strategic metals, commodity prices are rising and the scarcity of some metals is increasing. Europe’s technology sector is also affected by this growing shortage of metals. Securing the supply of critical metals is now a major element in Europe’s economic strategy. The Blue Mining and Blue Nodules projects have been initiated to principally advance deep sea mining technology beyond current TRL-levels.These critical metals are found inside so-called “polymetallic nodules”, lying on the seafloor in deep-sea environment. These nodules have a typical abundance of 10-25 kg/m2 and a size range of 10-125 mm.Harvesting the polymetallic nodules is challenging. Two main methods of harvesting or collector equipment are distinguished: hydraulic and mechanical. Over the last year, Royal IHC has designed, build and tested a full-scale hydraulic collector. Meanwhile, a mechanical collector is being developed.First, a scaled version of the hydraulic collector was developed and tested in order to have a proof of principle. The development as well as optimization were aided by multiphase CFD simulations."

Jan 1, 2017

By Paul Kennedy, Daniel R. McConnell, Ruth Price

"The underwater search for the passenger aircraft MH 370 produced rare high resolution datasets of the ocean floor of extraordinary size and detail. The survey design and operations were for sole purpose of finding the aircraft debris field. The aircraft was not found in the detailed search area and the survey was suspended. As planned, the data are now being made available to scientists and researchers. The large survey area includes geologic settings that might be prospective for seafloor minerals. A review of the data can provide insights to seafloor mineral prospectivity in the Southern Indian Ocean and is a large dataset that can be used to calibrate object detection for the design of dedicated mineral exploration surveys.Economic minerals in the Southern Indian OceanOceanographic research and scientific drilling cruises have assembled geologic and geophysical data points in the Southern Indian Ocean. These, together with satellite derived bathymetry and gravimetric data, earthquake mapping, and mapping of magnetic anomalies have, even if they lack detail, produced a general understanding of the main tectonic features and plate movements in the Southern Indian Ocean as well as contributed some marine mineral data.The Southeast Indian Ocean Manganese Pavement, a large manganese nodule field south of Diamantina Fracture Zone was discovered in 1970. Dredging and photographic data from the discovery cruise determined that dense nodule accumulations cover 900,000 sq. km."

Jan 1, 2017

By David Heydon

NAUTILUS MINERALS is a leader in the commercial exploration for and evaluation of seafloor massive sulfide (?SMS?) deposits. Nautilus has exploration licences covering 15,000 sq km of seafloor in Papua New Guinea and is evaluating other areas in the Western Pacific. The Nautilus Western Pacific Gold-Copper project is an interesting case study of the interaction of the disciplines of Science, Engineering and Environmental Science to solve and attend to the challenges of a project without precedence. The Science books of geology and marine biology with respect to seafloor massive sulfides are still being written or at best are thin volumes with recognition still we know very little at this time. Science?s early discoveries and study of these mineral processes on the seafloor provided invaluable data from which to develop an exploration strategy and the genesis of Nautilus itself. The Engineering required for development of such deposits is a combination of yet to be tested ?theory and engineering principles? and adaptation of best practice from other fields such as oil/gas and telecommunication cable laying. The Environmental guidelines for exploring these deposits, let alone mining them, is at the moment still being debated by a panel of experts chosen by the International Seabed Authority.

Jan 1, 2005

By John Halkyard

Deep ocean mining is experiencing a rebirth following many years of low levels of activity. Large scale mining is being projected as just over the horizon. A lot has been made of the advances in deep water oil and gas developments over the last thirty years, and how this technology is directly applicable to ocean mining. The authors present their views on this from a perspective of a legacy of participating in the development of manganese nodule mining systems in the 1970s, followed by thirty years in the deepwater oil & gas arena. While it is true that great advances have been made in subsea technology, the differences between mining and oil and gas recovery should not be diminished. Fundamentally, oil and gas are stored in compact reservoirs under pressure. Any intervention leads to flow of the material up a pipe to the surface. The seabed hard minerals are stuck in place, either adhering to sticky pelagic sediment (nodules) or bonded together as hard rock (massive sulfides). The minerals require complex machinery in order to be extracted, sized, concentrated and lifted to the surface. Once at the surface the ore must be dewatered, de-fined and transferred to shore for processing. The overflow from this dewatered product must return to the sea in an environmentally satisfactory manner. These steps involve technology unique to mining that has to be addressed in a methodical fashion before commercial mining systems can be designed. The presentation will discuss the critical technical challenges of deepsea mining and thoughts on different routes to commercialization. The program will address the critical technical challenges, as perceived by the authors, and steps required to address them. Alternate development programs will be discussed focusing on nodules and sulfide. Keywords: manganese nodules, polymetallic sulfides, ocean mining

Jan 1, 2011

By Charles L. Morgan

In a commercial effort to characterize deep seabed manganese deposits in the Clarion-Clipperton region of the northeastern tropical Pacific, Ocean Mineral s Company carried out 16 expeditions to the region between -1978 and 1981. During these cruises OMCO collected substantial data. Activities included acoustic profiling, video and photographic imaging of the seabed, and sampling of the deposits with dredges, box cores and free-fall grab samplers. In 1990 the samples, photographs, technical reports and computer data bases which resulted from this work were archived at the Marine Minerals Technology Center at the University of Hawaii. This preliminary examination of the collection focuses on the biological observations made from almost 10,000 photographs of the seabed and the manganese nodule size distributions and compositional data from the free-fall grab recoveries. Regional trends are evident in all three data types. The biological examinations of the seabed photographs show significant geographical trends, with greater abundances of organisms being noted in the northeastern extreme of the region, decreasing toward the southwest (11.4 to 2.7 observations per 100 m2; 460 to 190 g per 100 m2). The nodule size distributions suggest that the ratio of the nodule burial rates to growth rates systematically decreases over the same range (0.65 to 0.36 nodules buried per 1 cm of growth). Preliminary geostatistical analysis of the ore grade data show that, in addition to high local variability, some deposit

Jan 1, 1991

By T. Kuhn

The Logatchev hydrothermal field is situated on the east inner flank of the rift valley of the MAR at 14°45?N and is hosted by serpentinized peridotites and minor gabbronorites while basalts are subordinate. Hydrothermal precipitates recovered from the Logatchev field during a recent R/V Meteor cruise include massive chalcopyrite chimneys, massive pyrite crusts, silicified breccias, abundant secondary Cu-sulfides, red jaspers, abundant Fe-Mn-oxyhydroxides as well as atacamite and Mn-oxides (Kuhn et al., 2004). Previous results of hydrothermal fluid studies in the Logatchev field are somewhat at odds with theoretical models of ultramafic-seawater reaction. Butterfield et al. (2003) suggested that the Fe component of orthopyroxene plays the more important role compared to olivine in ultramafic-hosted hydrothermal systems. This consideration is supported by the recovery of large amounts of Opx-rich gabbronorites and orthopyroxenites in the Logatchev field (Kuhn et al., 2004). A possible tool to constrain the contribution of the different rock types (ultramafics, mafics, MORB) to a seafloor hydrothermal system is the systematic analysis of 187/188Os ratios of the host rocks as educts and the sulfides as products. For instance, abyssal peridotites mainly display low 187/188Os ratios (<0.127); in contrast MORB and gabbronorites have radiogenic ratios of >0.13 (Snow and Reisberg, 1995), orthopyroxenite has ratios of about 0.174 (Büchl et al., 2002) and seawater has an ever higher 187/188Os of about 1 (Sharma et al., 1997). Therefore, massive sulfides predominantly leached from ultramafic rocks should have Os isotopic ratios plotting on a mixing line between the ultramafic rocks and seawater (in a 187/188Os vs. 1/Os diagram), whereas those derived from MORB, gabbronorites and/or orthopyroxenites will be plotting on different mixing lines.

Jan 1, 2004

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&apos;W to 2 40&apos;W, and between the shoreline and approximately the continental shelf edge north of 4 30&apos;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 Peter A. Rona

Hydrothermal mineralization along slow-spreading oceanic ridges and rift -zones that comprise more than half the global length of the seafloor spreading center system is related to anomalous physical and chemical conditions acting within the geologic settings that characterize early and advanced stages of opening of an ocean basin. Mineralization in the early stage of opening is represented by the Atlantis II Deep of the Red Sea. There, hypersaline hydrothermal solutions discharging as density stratified brines into an axial basin, have formed the largest massive sulfide deposit (70 x 106 metric tons) known at a spreading center. Mineralization at the advanced stage of opening is represented by two types of sites: (1) oceanic crust on the wall of a rift valley; and (2) oceanic crust exposed on the wall of a transform fault zone. The first type of site is the TAG Hydrothermal Field, located on a wall of the rift valley of the Mid-Atlantic Ridge at the top of the basaltic layer of oceanic crust. Evidence is presented for multi-stage, high- and low-temperature hydrothermal activity that produces Cu, Fe, and Zn enrichments within the thin sediment column and stratiform interlayered deposits of manganese oxides, iron oxides, hydroxides and silicates, on the seafloor. The second type of site occurs along walls of transform fault zones of the equatorial Mid-Atlantic Ridge and Carlsberg Ridge, which exhibit stockwork-type Cu-Fe sulfide mineralization

Jan 1, 1985

By D. S. Cronan

Mineral exploration problems in the S.W. Pacific are not unique to that region, but a combination of favourable circumstances render it an ideal area to attempt to solve such problems. The land area of the S.W. Pacific island nations is only a fraction of the total sea area they can claim under current International Law. Hence, they have a great need to explore and evaluate their offshore areas. For the past ten years the focus of this work has been CCOP/SOPAC which has individually and jointly with other groups initiated and maintained far reaching marine mineral exploration programmes. In association with CCOP/SOPAC the writer has obtained and analysed approximately 650 sediment samples from the S.W. Pacific region for seventeen elements. Multivariate statistical techniques have been applied to the data set. The aim has been to identify chemically anomalous sediments reflecting either sea floor mineralisation and/or mineralisation on adjacent land areas.

Jan 1, 1985

By Richard H. T. Garnett

On the western continental shelf of southern Africa diamonds derived from onshore sources are concentrated in gravels within drowned terrestrial and marine geomorphological features. First discovered offshore in the late 1950&apos;s, they are known to exist for about 1400 km along the Namibian and South African coast in water depths of up to 200 m. Shallow water operations yielded 1.5 Mct during the decade ending 1970 when De Beers acquired a majority of the offshore leases and commenced a 15 year exploration program. Deeper water and the prevailing sea conditions required the development of new, unique, marine mining equipment. The first large scale mining production of 22 kct was achieved by De Beers in 1989 with an output of 22 kct. Annual marine output from all sources now exceeds 0.6 Mct worth some US.$ 170 M, and rising to 0.7-0.8 Mct for 1998. Exploration has also been taking place in the waters of West Africa, Australia, and Indonesia. Exploration is by means of high resolution geophysics followed by sampling using a variety of drills, airlifts and seabed-mounted machines which imitate the eventual mining process. Surveying is now probing depths of 500 m. Smaller scale mining by several junior companies has traditionally involved diving and airlift systems. Increasingly, however, they are adopting different and improved techniques which to date have been employed only by De Beers Marine as contractor to Namdeb. Marine exploration and unit mining costs are high compared to those applicable to alluvial deposits onshore. By 1996 the total development costs incurred by De Beers alone reportedly had exceeded US.$ 500 M. However, the financial rewards are commen-surate because of the higher recovered grades. The operations are not without risk for the total of nearly 10 large and medium scale production vessels deployed by various organisations. The greatest shortfalls are experienced in the estimated throughput, not the grade.

Jan 1, 1998

By Tony van der Steen

Subsea mining system are designed for the following, principally different, tasks: Dreding - The destruction and removal of seabed sediments overlaying the bedrock. Cleaning - The competence of the system to systematically remove the deposits from an undulating hard bedrock with irregular pulleys, channels and fissures. Factors that influence the choice of dredging equipment for a specific project are project requirements such as environmental conditions, location and water depth. However, the most important selection criteria are soil conditions. As a consequence, possible dredging systems, must be evaluated for the following, principally different, characteristics: Dredging proficiency - The destruction of the strata by the equipment. System stability - The capability of the soil to support the subsea equipment The above parameters are determined by the strength characteristics and the bearing capacitv_ of the soil. The author describes the processes involved in excavating the subsea deposits and (transporting the gathered soil as a water-soil mixture to the surface using different excavation and transport methods.

Jan 1, 1998

By David Huber, John Halkyard

Deep Reach Technology, Inc. recently completed a multi-year cooperative research project for the U S Army Research Laboratory for the purposes of investigating recovery of rare earth elements from the seabed. This research led to the discovery of a potentially economical deposit in the Exclusive Economic Zone of the Cook Islands. In order to further develop this resource, Ocean Minerals LLC (OML) was formed in 2016 to explore the development of a deep-sea mining project to recover rare earth elements and scandium from the upper 10m of sediment in promising areas of the Cook Islands Exclusive Economic Zone. OML and the Cook Islands Investment Corporation signed an Agreement in 2016 giving OML exclusive rights to explore a 12000 sq km area and option rights over an additional 48,000 sq km. This poster presents the current status and activities related to this project.

Jan 1, 2017

By John Parianos, Simon Richards

SUMMARY The Clarion Clipperton Zone (CCZ) hosts the most valuable deposit of polymetallic nodules yet discovered. Understanding the geology of this deposit is key to its effective exploration and mining. Nautilus Minerals (via its subsidiary Tonga Offshore Mining Limited; TOML) has been progressing its understanding of the relationship between seafloor morphology/structure and nodule abundance/morphology, both locally (within its contract areas), and globally (across the CCZ and the span of its contract areas of almost 70% of the CCZ). We present the first results of a project with the aim of developing a method to quickly and accurately map seafloor morphology/structure (Tectonic Subcomponent scale) without the necessity for high resolution seafloor multibeam data. Furthermore, the results presented here will allow a first attempt in understanding the relationship between seafloor geomorphologically-defined zones and plate-scale tectonics of the CCZ and adjacent plate segments. INTRODUCTION A relationship between the type of geochemical active layer and nodule abundance/morphology has long been understood (ISA, 2010). Consideration of the range of differing nodule types found within, but especially between, the TOML contract areas allowed Parianos and Pomee (2017) to refine this relationship further via interpreted thickness and dynamism of the geochemically active layer. The scale of the deposit, both in terms of space and time is staggering (a 10-20 cm thick deposit, spanning almost 4500 km, varying within a circa 10 Ma period), but a segment wide geological map may one day prove to reflect controls on nodule formation and distribution.

Jan 1, 2018

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

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 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 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 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