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

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

Jan 1, 2018

By 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 Marlene Olivares Cruz

The particles that make up the deep-sea sediments have two main sources: 1) those that are created in situ from dissolved components and 2) those that are washed into the ocean in solid phases from the continents, atmosphere, space and interior of the Earth. Many particles as they sink through the water column reaches the seabed and are known as pelagic sediments with terrigenous, biogenic, authigenic, and cosmogenic components. Among the minerals found in the terrigenous fraction of pelagic sediments are quartz, clay minerals, feldspar, micas, ferromagnesians, and the biogenic fraction with remains of siliceous organisms, such as, radiolarian and diatoms. The chemical nature of marine sediments is controlled by the contribution of particulate matter derived from various sources with varying compositions for the fixing of elements during deposition and the compositional changes carried out within the sediments during diagenesis. In the last decade there have been several studies on the mineralogical composition of seabed sediments, suspended particulate materials and cores, together with paleontological and geochemical data are used for paleoclimatic and paleoenvironmental reconstructions, analyze changes in sea level, stratigraphic correlations and identify past and

Sep 14, 2011

By Johnson R. Cann

Ocean floor sulfide deposits are now known from many parts of the world mid-ocean ridge system and from some seamounts. Clearly they can be expected to occur commonly on the ocean floor. However, only two or three of the known deposits appear to approach the million-ton size, and in none of the deposits has the grade been well-defined. Can knowledge of the processes that happen within the hydrothermal plumbing below deposits help define the conditions under which large, high-grade deposits form? Here I review present knowledge of ocean-floor hydrothermal processes to attempt a first answer to this question. There are three sources of information about these processes. The solutions emerging from active systems must be compatible with patterns of alteration that underlie the volcanogenic sulfide deposits of ophiolite complexes, which are slices of ocean crust thrust onto land. Both of these types of evidence can be linked by computer modelling of the exchange of heat and metals between rocks and flowing water.

Jan 1, 1988

By Glen Smith

Nautilus Minerals, the world?s leader in exploration and development of deep ocean seafloor resources, is today focused on the recovery of high-grade copper and gold in seafloor massive-sulphide mineralization. These targeted mineralized belts, analogous to land-based volcanogenic massive sulphide deposits, are located near plate boundaries in the back arc basins of the Western Pacific. The first deposit to be developed by the company is located at a depth of 1,600 meters at Solwara 1, in the benign waters of the Bismarck Sea. This location lies within the territorial waters of Papua New Guinea. From 2006 to 2009 the company completed detailed environmental and geological studies at Solwara 1, culminating in a number of world firsts, including the first Environmental Permit granted for the extraction of seafloor massive sulphide deposits and the first NI 43-101 compliant seafloor massive sulphide deposit resource statement. Nautilus has relied heavily on proven deepwater technologies from the oil and gas industry in the design of its production system. Pipeline trenching units, workclass ROVs, deepwater production risers and drill cuttings removal systems will be adapted to initiate this new and exciting industry. Key contractors used by Nautilus on this innovative project have all been selected for their deepwater experience (gained in the oil and gas industry), creativity and determination to launch this new industry successfully. Innovation is at the forefront of Nautilus? success to date. This paper summarizes the progress to date of this development which will provide a new source of minerals for the world and which will contribute to sustainable growth for the future.

Jan 1, 2010

By John Parianos

2013 has seen good progress for Nautilus Minerals and our projects due to the determination of our people and the continued support from shareholders and stakeholders. Our focus remains Solwara 1 in Papua New Guinea for which the build continues on the seafloor production tools, subsea slurry pump and riser and lifting system.

Sep 14, 2011

By Toru Yamasaki

A concept of plate-tectonic controls for the formation of seafloor massive sulfide (SMS) deposits in back-arc settings was established by Franklin et al. (2005). According to Franklin et al. (2005), a consequence of extension and rifting is subsidence, thinning of the crust, and the rise of hot, athenospheric mantle into the base of the crust. Underplating of the crust by mafic magmas results in low-pressure partial melting of the hydrated crust at a <15-km depth, and the generation of felsic anhydrous melts. The rapid ascent of hot felsic melts, along with mantle-derived mafic melts, results in bimodal volcanism that characterizes rift and volcanogenic massive sulfide deposits (VMS) environments. The rapid and focused advection of the magmatic heat within the rift to the near-surface environment which are required to sustain vigorous long-lived VMS hydrothermal systems. Faults within rift environments may also allow seawater to penetrate into subvolcanic intrusions and mix with magmatically generated metalliferous fluid or allow a direct magmatic contribution from shallow crustal level (3–12 km) magma chambers (Franklin et al., 2005, and references therein). In addition, the caldera-forming processes are favorable for the formation of VMS deposits and the focused high heat flow and cross- stratal structural permeability that is restricted in time and space to caldera development provides an explanation for the clustering of VMS deposits and their restriction to specific time-stratigraphic intervals and structures in the evolution of submarine central volcanic complexes (Franklin et al., 2005, and references therein). The concept is persuasive, although it is based on a series of logically constructed reviews mainly focused on ancient on-land deposits.

Jan 1, 2018

By Irina A. Pulyaeva

Hydrogenetic Fe-Mn crusts play an important role in marine mineral-deposit research because of their widespread occurrence and high concentrations of valuable and rare metals. Most Fe-Mn crust deposits occur on the tens of thousands of seamounts found in the global ocean as well as on ridges and plateaus. Because of these circumstances, it is essential to clarify a number of outstanding issues with regard to Fe-Mn crust history and development, including controls on metal sources and concentrations. The first-order characteristics of Fe-Mn crusts as potential ore deposits include concentrations of metals (grade) and the thickness of crusts (tonnage), which vary depending on Fe-Mn crust structure and texture. Data on the structure, composition, age, and deposit characteristics will help define which factors are key for the creation of mineral accumulation and which combination of factors leads to the formation of potentially economic concentrations of metals. In this paper, we address the structure and characteristics of Fe-Mn crust stratigraphic sections collected from Central and Western Pacific seamounts. We describe the changes in mineralogical and chemical compositions of crust layers of different ages, the occurrence and regional distribution of these layers that correlate regionally, and reconstruct the paleoceanographic conditions that influenced crust growth.

Jan 1, 2010

By Alexander Malahoff

Accumulation of cobalt -rich ferromanganese crusts on Pacific seamounts located off-ridge in the Hawaiian EEZ, represents a complex process that involves geologic aging of the seamounts, geographic transportation- of the seamounts on the Pacific plate during the past 80 million years, and geochemical history of the oceans for that period. A comparative study of the building and erosion processes of the young Loihi Submarine Volcano, located south of the Island of Hawaii , and the 80 million year old Cross Seamount, located west of Hawaii , shows that both edifices show wide armchair-shaped talus chutes and intervening ridges of exposed dikes. The similarity between the observed mass wasting process on Loihi and Cross suggests that the slopes of submarine volcanoes are geologically unstable from the time of their origin on the seafloor through their entire geological history. The slopes of Cross are covered by coalesced ferromanganese crust covered talus, steep exposed dike faces, and crust covered dike ridges. A study of the stratigraphy of the crusts shows a range of thicknesses and number of unconformities present. The thickest crusts, up to 8 centimeters, are found preserved within the larger coalesced slabs along the shallower slopes of the talus chutes and along the crests of the ridges between water depths of 400 and 1800 meters. The platinum content was used in stratigraphic correlation between the crusts in the coalesced slabs and those collected from ridges with the PISCES V submersible. In the samples studied, the highest platinum content of 0.7 ppm

Jan 1, 1991

By Hyun Sub Kim

Subsea mineral deposit exploration aboard the R/V Onnuri was performed along the northern Central Indian Ridge (CIR) between 8°S and 17°S in December 2009 ~ January 2010 (09IR Leg01 and 09IR Leg02) and December 2010~ January 2011 (10IR Leg01, 10IR Leg02, and 10IR Leg03). Final goal of the expedition for the first Korean research cruise on mid ocean ridge system is to define seafloor massive sulfide ore bodies through searching the active hydrothermal vents nearby spreading centers as well as to elucidate the nature of spreading segments of the northern CIR area where no systematic survey have been operated before by mapping and sampling of volcanic rocks. The preliminary result of topographical interpretations of bathymetry clearly display ocean core complex between 10°S and 11°S. The ocean core complex is featured by topographic-high area with corrugated surface. Lineaments of corrugations of the ocean core complex are clearly perpendicular to abyssal hill direction which is triggered by symmetric-normal faults. Ocean core complex are favor for hydrothermal fluid path because of the long-lived faults. In further exploration, more detailed examination, including systematic CTD casting and tows, need to narrow down actual venting site around ocean core complex. Magnetic field survey is able to estimate the location of hydrothermal vents with the properties that high temperature of hydrothermal fluids over Curie-point can cause thermal demagnetization. In magnetization intensity map, most of low magnetization zones are located at the nodal point over the ridge axis and the ocean core complex.

Jan 1, 2011

By André. C. Louw

Diamond production from the reworked beach and river channel gravels along the west coasts of South Africa and Namibia is well known throughout the world, not only for the exceptional quality of the diamonds, but also for the sheer scope of the operations. To date an estimated 140 million carats have been produced from the resource worth some US$40 billion in today&apos;s money terms. It is therefore not surprising that it didn&apos;t take long before the attention turned towards the possible extension of this valuable diamond resource on similar submerged beaches in the adjacent territorial waters of South Africa and Namibia. This has proved to be a very successful move as the marine production in Namibia today constitutes 48% of that country&apos;s total diamond production. Although small scale recovery of diamonds from the sea commenced in the 1950&apos;s, the first large scale production came from the operations of the Texan entrepreneur, Sam Collins, in the 1960&apos;s. The De Beers Group, which took over Sam Collin&apos;s operations in 1969 had all the concession areas, as well as the financial and human resources to tackle the new mining frontier in the correct way by years of data gathering (ie diamond reserves and seafloor terrain studies) before commencing with large scale mining operations in the 1980&apos;s. Those who are familiar with the beach mining operations along the South African and Namibian west coasts will have appreciation for the daunting task of surgically removing the payable portion of diamond deposits from the non-payable material on the one hand, and the complex uneven fractured and gullied bed-rock floor of the deposits on the other hand. Not to mention the additional complexities of large boulders and hard calcretised diamond gravel layers (conglomerate) which are sometimes associated with the deposits. It was a natural development that the sea diamond mining operations were approached with the known information of the land operations, attempting to duplicate land mining operations in the sea, but taking cognisance of the variations of the terrain in the different areas. For instance, we encounter the following variations, and combinations, off the Namibian Coast. ? Close inshore - holocene sand cover often masks large areas of potentially diamondiferous gravels. ? In midwater areas (40m - 100m)

Jan 1, 1998

By Hjalmar Thiel

Since industry is progressing into the deep sea, marine scientists have expressed their concern about environmental disturbances which will be introduced by using the deep seafloor for mining metalliferous resources or as a repository for wastes. Environmental studies have been conducted on national levels and in bilateral or multilateral cooperation in the development of manganese nodule mining, as this is generally achieved in marine research. These investigations were partly large-scale and experimental approaches aiming at the assessment of the impacts expected to occur in commercial mining. The results elaborated till today and expected to be acquired in the foreseeable future may remain limited. Reliable impact evaluation will result from monitoring a Pilot Mining Operation (PMO). The lecture will present the broad outlines of a possible program and a preliminary calculation of approximate costs for such a combined industrial test and environmental monitoring event. Although the extent of necessary efforts for the environmental risks evaluation can only be estimated rather vaguely, it will become evident that the required human, technical, logistical, and financial resources to be mobilized will exceed industrial capacities and go beyond national funds. Therefore, such assessment of environmental risks is calling for broad international cooperation. While industrial developments for mining the deep sea will be ruled by competition or probably by restricted joint ventures, environmental care ranges outside competition and falls within the interest of all parties involved. Environmental studies, unlike technologies for the same function, do not primarily need duplication. International cooperation in PMO monitoring would equally well support all mining companies or consortia, it would minimize the efforts for all engaged in this challenging venture of deep-sea mining and it would maximize the precautionary discussion on and the care for the deep-sea environment.

Jan 1, 1994

By Mark Vardy, Kate Dobson, Isobel Yeo, Paul Lusty, Bramley Murton

In response to anthropogenic climate change, the way in which we use and generate energy is changing. To facilitate these developments, it is essential that we increase and diversify the supply of ‘E-Tech’ elements essential for cleaner energy generation and more efficient usage. The vast majority of these materials (e.g. cobalt, lithium, niobium, platinum group metals, rare earth elements and indium) come almost exclusively from mining and new resources must be found and developed in order to secure supply and meet the demands of the future. Ferromanganese (FeMn) crusts are rich in cobalt, tellurium and rare earth metals, and are common on seafloor hard grounds at water depths over 1000 m. The mining of both FeMn crusts and nodules is potentially viable dependent of the balance of cobalt and nickle prices (Martino & Parson, 2012), however, crusts need to be at least 4 cm thick with cobalt contents of at least 0.8% (International Seabed Authority, 2008). The difficulty for those wishing to exploit these resources is firstly finding them, and secondly assessing their potential remotely. Such capability would not only save time and money, but also allow mining operations to be more focused, reducing needless destruction of seafloor habitats from exploratory mining or mining of noneconomically worthwhile deposits. In this contribution, we examine the distribution of crusts on a single Atlantic Gyot (Tropic Seamount), the morphology of FeMn crusts, their variable growth patterns and the characteristic geophysical response from crusts in various datasets, including ship based 60 m resolution multibeam and high resolution bathymetry, backscatter and sub-bottom profiler data acquired using an Autonomous Underwater Vehicle (AUV).

Jan 1, 2017

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 Valery M. Yubko

"The conceptual basis of the developed model is based on the ideas that evolution of geological-geomorphological structure of the CCZ is controlled by four types of geologic factors: geodynamic, sedimentary, volcano-tectonic and erosion-lithodynamic. In terms of time span two factors (geodynamic and sedimentary) can be considered as permanent and the other two as sporadic.The geodynamic factor is responsible for two interrelated geological processes. One is going under conditions of the axial zones of spreading centers and results in formation of the CCZ basement. Historically this process is considered as a starting point for each of the heterochronous fragments of the CCZ. The second one controls gradual shifting towards the Pacific Plate (Hawaiian direction) and subsidence to greater depths of the neogenic fragments (basement). Thus, those processes control basic topography, geomorphology and the seabed depth within the CCZ.Volcanogenic-hydrothermal activity of the EPR is one of the main sources of the ore components, which finally compose manganese nodules as a result of complicated processes of their dissemination and transportation to the bottom in dissolved and organically bound forms.The role of the other constant factor (sedimentary) is displayed in two ways. Firstly, initial relief is smoothed under the influence of this factor, which, subsequently, makes favorable conditions for manganese nodules formation. Secondly, it favors transportation of the majority of the ore components, participating in manganese nodules formation into zones of active nodules formation."

Jan 1, 2017

By S. W. McCandless

Since the mid 1970&apos;s, the science of remote sensing has invented and demonstrated sensors that hold unique promise for users that operate in the marine environment. Earlier, visible and infrared sensors provided images and temperature maps of surface conditions, but the 1970&apos;s introduced active (radars) and passive (radiometers) microwave sensors capable of penetrating clouds and operating day or night over the world&apos;s oceans. Space-based observation satellites permit these systems to span the globe many times each day, providing a view of the world&apos;s oceans and Arctic areas consistent with daily and, sometimes, hourly changes in the marine environment. Experimental satellites launched by NASA proved that such systems had great scientific merit, but, even more importantly, they could produce information valuable to marine transportation, fishing, and resource exploration and extraction. This latter subject includes the off-shore search and production of petroleum and natural gas resources and ocean mining as well. A few early satellites, such as GEOS-3, Nimbus-7, and most notably Seasat established that global wind fields, all weather sea surface temperature, ocean topography and sea state, and fine scale images of wave patterns, surfactants,

Jan 1, 1986

By Tap Pryor

A very small nation with large seabed resources requires a strategy. The simplest approach is to duplicate every step taken by the United Nations (UN), in its own leasing programme. In addition, the smaller nations must sell itself and its competitive offering. It is one thing just to await applicants and/ or tenders, another to work to make the leasing seem like a very good idea. This cap be achieved through publications, correspondence, meetings (such as the Underwater Mining Institute, but especially through pro-active planning, seeking the ideal technologies in both harvesting and processing. The ideal would be some combination that could begin quickly and on a small scale. It must be within the UN environmental guidelines. To meet the "quick and small criteria," simple harvesting and physical processing methods must be given the highest priority. Once these are satisfied, then marketing studies can be completed. There is, of course, a market for every element but only careful engineering and cost analysis will determine accessibility. What is required is a stepwise approach, gaining greater and greater credibility at each step. In fact, much planning can be done for very low cost. In the Cook Islands, the first crucial step was the East-West Center publication which pulled together all facts in one volume and which found the local resource to be richer in significant ways than Clarion-Clipperton. Most seem to believe that it could be many years before full production is possible, but this has been conventional wisdom for so long that it has taken on the suspicious aura of myth. Is it real? Have all possible recent technologies such as robotics and physical processing been taken into account? Either way, it is essential that a comprehensive approach be taken so that all factors from resource to market are considered as inter-related until a single business plan emerges. When that is in hand and when its profitability and risk levels are found to be credible, adequate investment funds are available.

Jan 1, 1994

By Richard Petters

Williamson and Associates, Inc of Seattle, Washington has recently built a remotely operated seafloor coring system for Nichiyu Giken Kogyo Ltd and the Metal Mining Agency of Japan (MMAJ). The system is designed to core to depths of 20 meters in 6,000 meters of water and will be operated from MMAJ&apos;s research vessel Hakurei-Maru No. 2 The corer uses rotary rod coring methods and will recover a core diameter of 44 mm. To facilitate coring through soft or unstable formations, the corer has the ability to set casing. The corer is fitted with thrusters for positioning during landing and telescoping legs for leveling. The system is operated through a 12 km electro-optical cable. Data displayed to the operator provides the operator with real-time feed back and control over the coring process. The operator has independent proportional control over bit weight, advance rate, rotary speed, and flushing water flow. The process of making up, breaking down and storing the drill string is automated and is controlled by a logic driven software routine. The system is currently undergoing trials in Japan. This presentation will discuss the drill&apos;s capabilities and should be of interest to those in need of a tool for assessing the thickness of marine mineral deposits.

Jan 1, 1996

By Yuta Yamamoto

Seafloor massive sulfides (SMS) which contain Au, Ag, Cu, Zn, and Pb have been interested in as a target of commercial mining these 15 years. Japan has large potential of SMS and a national R&D project for the mining has been active these 5 years. However, the economy of SMS mining is very bad, because the waste tailing disposal cost is very expensive in Japan. A slurry flushing method is experimentally examined in this study for the improvement of the economy. During the flushing, because of density difference between the metal-rich ore and the waste rock, a kind of gravity separation is possible. The results suggest a possibility of the actual application.

Sep 14, 2011

By Laurie Meyer

The need for improved, high confidence estimates of nodule abundance to support mine permitting, detailed mine planning and mining and processing equipment design is evident. To date, physical samples represent the ?Gold Standard? for nodule abundance measurement, and are likely to remain as such. However, there are some interesting improvements in the area of 3-D scanning which, if marinized for operations at 6000m, may prove to be reliable alternative methods for mapping abundance over large areas particularly if calibrated or benchmarked with physical sample data. . Features of a high confidence physical sampling device, such as the 0.75m2 (0.86m on a side) box corer developed and successfully used by the Kennecott Group for exploration in the CCZ, take into account not only the accuracy in nodule sample collection but a host of other operability considerations which can mean the difference between a successful exploration cruise yielding high numbers of large area samples and one in which few, inaccurate, often inconclusive samples are collected (or, even worse, the sampler fails to grab any nodules for any number of reasons). The collection of physical samples at appropriate spacing within a mine area combined with more qualitative indications of nodule density such as can be obtained using acoustic backscatter should prove adequate for the near term objectives related to overall abundance appraisal or estimates of ?indicated? resource. Looking ahead, exploration cruises will need to yield increasing amounts of data to support development of higher confidence resource abundance estimates to support issuance of mining permits and detailed design of mining plans and equipment. It is likely

Sep 14, 2011