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By James M. Cairns

Deep Sea Minerals Inc. (DSM) is a high technology marine minerals and biotechnology corporation. The corporation is currently engaged in a worldwide leasing program to acquire exclusive rights in specific Economic Exclusive Zones (EEZ?s) that DSM?s marine geologists have identified as prospective targets for seabed mines of copper, zinc, gold, and silver. In the last two years the corporation has assembled an international team, including some of the world?s leading marine research scientists and engineers, and has created strategic partnerships and alliances with world-class engineering and mining groups. Development of a marine mining venture has key requirements in common with most other mining ventures. These include financing, deposit location, property acquisition, deposit delineation, and permitting, as well as the collection, transportation, processing and marketing of the ore itself. DSM has made progress on all of these fronts, which is outlined in a general way in this presentation. Financing for the venture is clearly the first big hurdle to overcome. Deep seabed mining involves new technologies and significant up-front capital investment. Less than fifteen years ago, such financing would probably have impossible to achieve, given classical business models. However, with the spectacular success of high technology ventures in the areas of electronics, software, and biotechnology, new business models and investment strategies have evolved which put relatively high evaluations on intellectual property and exhibit relatively high confidence in new ways of doing things. DSM is taking full advantage of these changes in venture capital markets in its financial planning.

Jan 1, 2000

By Alexander Malahoff

The most exciting frontier in Ocean Technology is represented by a new class of Marine Bioproducts, the source of which lies in marine microorganisms. The microorganisms include microalgae, bacteria and archaea. These organisms represent very diverse, adaptive life forms and in their metabolic processes use carotenoids, polyunsaturated fatty acids, ultraviolet blockers, as well as a wide range of enzymes that are pivotal in the production of new pharmaceuticals and nutraceutical products. These organisms cover a wide spectrum of ocean environments, from the shallow to the deep, from the normal to the extreme. The technological challenge is in the identification of candidate organisms, in the screening for valuable enzymes, and in the industrial production. A whole new range of collecting strategies involving submersibles, ROVs and in situ ocean floor instrumentation is emerging. New non-polluting industrial chemical processes involving the use of photobioreactors and extremophile bioreactors for breeding and monitoring these organisms in neo-farming technology is emerging. The commercial value of these candidate products is immense, as is the range of potential organisms. The dimension of this new industry is global. The Marine Bioproducts Engineering Center (MarBEC), funded by the National Science Foundation (NSF), has been established at the University of Hawaii. The vision of MarBEC is to develop a seamless research system stretching from undergraduate education to industry for the purposes of producing valuable marine bioproducts outside of the normal chemical factory production. MarBEC is uniquely and strategically placed in the Pacific to explore, find, and adapt highly bioactive marine micro-organisms found in the tropical ocean. We have watched the increasing need by the ever-

Jan 1, 2000

By Rahul Sharma

Although, mining of minerals such as polymetallic nodules and sulphides from the deep sea floor has been delayed due to the combination of factors such as current availability of Cu, Ni, Co, Mn (and other metals) on land and their fluctuating prices; these deposits are still considered as the alternative source for metals in the 21st century. Exclusive rights for exploration in the ?Area? (beyond the national jurisdictions of any country) given to eight countries and consortia by the International Seabed Authority and the estimated resource of 300 million tonnes in a typical area of 75,000 km2 is expected to yield about $17.5 billion (at December 2008 metal prices) in 20 years life span of a single nodule mine-site. In order to recover 3 million tonnes of nodules, an area of 300 sq km only will be mined annually (i.e. <1 km2/day) for an optimum abundance of 10 kg/m2. However, during mining, large quantity (22 tonnes/day) of sediments associated with nodules would be resuspended that could lead to certain environmental impacts on the benthic ecosystem. Several small-scale benthic impact experiments in the Pacific and Indian Oceans, have given some insight into the possible environmental impacts and the restoration processes, but the possibility of extrapolating these findings to a commercial mining scale remains an issue to be considered. An estimated capital expenditure of $1.05 billion and operating expenditure of $4.2 billion for a single deep-sea mining venture will have to be weighed against the availability of mineral ores on land as well as the metal prices in the world market. None-the-less, development of technologies for mining and metallurgical processing, as well as formulation of regulations and guidelines for potential ?contractors? to mine these minerals have been progressing consistently. These coupled with recent efforts by certain ?entrepreneurs? to initiate mining of seafloor massive sulphides in the EEZ of certain countries, indicate the continuing interest and support the perception that such deposits could well be the future sources of metals. This paper analyzes the current status and discusses the economic, environmental, and technical issues that need to be addressed for sustainable development of deep-sea minerals.

Jan 1, 2010

By Peter Halbach

Within the frame of the German-Indonesian cooperative Bandamin research project two short cruises (7 station days each) were carried out which led to the Flores-Banda basin located north of the active volcanic arc. This basin is part of a large island-arc subduction-collision system resulting from a complex plate tectonic situation in which three major plates collide with each other. The eastern part of the Sunda-Banda convergent margin also includes the transition from subduction of oceanic lithosphere to collision of the Australian continental crust with the arc. This transitional part is cut and displaced by various large obliquely striking fault systems. Thus, the south eastern and eastern arc segments represent geological conditions which are suitable for the development of hydrothermal convection and potential mineral precipitation. Our study area lies north of the transitional section between Flores and Wetar. We started with a high-resolution bathymetric mapping of 240 km2 in a region some 36 km north of the island of Lomblen. A small submarine neovolcanic ridge was discovered striking approximately NW-SE and consisting of several submarine volcanic structures. In the northwest of the study area, the active subaerial Komba Volcano (Batu Tara) marks the youngest continuation of the ridge system examined. From the ridge we collected fresh and hydrothermally altered volcanics with disseminated sulfides (pyrite, pyrrhotite, markasite, and chalcopyrite), together with ferrugenous gossans.

Jan 1, 2004

By Mayumi Ito

Seafloor hydrothermal deposits are found worldwide at 700 to 3,600 meters below sea level [1] and contain base and precious metals like Cu, Pb, Zn, Au, and Ag. Some deposits were found in the Japanese exclusive economic zone and the commercial potential will depend on developments in mining and treatment costs of onshore mines. The ores require mineral processing to become concentrate for the various metal smelters and the authors are investigating mineral processing treatments of collected samples. The collected samples were classified into three components (chimney, mounds, and substrate rocks) and they were separated using a RETAC jig. The mound component contains zinc, lead, and copper minerals and further separation using flotation was investigated. This paper introduces results of the mineral processing tests using gravity separation and flotation.

Jan 1, 2011

By Jeremy Spearman, Alan Cooper, Mark Lee, Jon Taylor, Michael Turnbull, Neil Crossouard, Bramley Murton

"SUMMARYSeamounts are underwater mountains caused by volcanic activity. They are of great oceanographic interest because of their local and basin-scale influence over ocean systems, their often unique ecosystems, and because they are associated with the formation of ferromanganese (Fe-Mn) crusts. These crusts are of particular interest to scientists because they are rich in some of the rare elements increasingly required for development of renewable technologies. When the possibility of mining such seamounts is considered, an inter-disciplinary study of seamount hydrodynamics, crust formation and ecosystem sensitivity is required. MarineE-tech is one such multi-disciplined project that has been commissioned to address these different aspects in order to improve understanding of the viability and desirability of mining Fe-Mn crusts. This paper describes a key part of this study, namely the development of a model, informed by hydrographic observations, of the currents around one such seamount and the in situ validation of a sediment disturbance plume model as a pre-cursor to assessment of the potential effects of mining activity.INTRODUCTIONFerromanganese crusts are thought to form by precipitation of iron and manganese oxides from oxygen depleted mid-water known as the oxygen minimum zone (OMZ). Oxidation rich waters, typically at depths of about 800-2200 m (Hein et al, 2000). This range of depths coincides with the flanks and summits of many seamounts. The ferromanganese crusts found on seamounts have been found to have high concentrations of rare elements, like Tellurium, that are considered critical to low-carbon energy production. Seamounts are complex environments: in terms of the local hydrodynamics that tend to trap water over the seamount due to the Taylor Cap effect (e.g. Chapman and Haidvogel, 1992) and which can enhance the productivity of seamount waters through upwelling (Lavelle and Mohn, 2010), in terms of the microbiological activity that leads to the precipitation of the Fe-Mn crusts, and also in terms of the often unique ecosystems that are the product of the “island” nature of seamounts and the upwelling of nutrients. The understanding of this complexity is a necessary journey towards the realization of viable, yet environmentally responsible, mining schemes. The formation of crusts will be influenced by the local (and larger-scale) hydrodynamics. The exploration of promising crust sites could be made much more efficient by understanding where the most prospective deposits are likely to occur. Knowing how to remove these crusts without impacting significantly on the local environment will be a pre-requisite for such mining to be acceptable to the public and funders alike."

Jan 1, 2017

By Sven Petersen

The southern Mid-Atlantic Ridge (SMAR) is one of the least-explored spreading centers in the world with respect to hydrothermal activity. In the past 8 years research focused mainly on the ridge segments close to Ascension Island, discovering hydrothermal fields as far south as 14°20?S (Haase et al., 2007; German et al., 2008; Tao et al., 2011). However, the vast majority of the SMAR ridge axis has never been thoroughly investigated for hydrothermal activity. In the spring of 2013 we used segment-scale AUV deployments as well as conventional CTD surveys to identify areas of hydrothermal activity along 16 mid-ocean ridge segments between 13° and 33°S, thereby covering close to 5 % of the global ridge axis in a single cruise. During cruise MSM25 of the German research vessel Maria S. Merian, we tested longrange (>100 km lines per dive) AUV deployments of GEOMAR?s AUV ABYSS (a Remus 6000 vehicle) along the spreading axis for their capability to locate active venting in a fast and efficient way on regional surveys. Since the missions covered long distances,

Sep 14, 2011

By Siân E. Boyd

Studies of benthic recolonization in the aftermath of marine aggregate dredging in the U.K. and elsewhere are limited and are largely confined to experimental circumstances. Investigations of the physical and biological status of licensed extraction sites in the U.K. at various times following cessation of commercial dredging are very limited, and so judgments as to the likely progress towards environmental restoration and the time-scales involved continue to be based on predictions rather than real data. This field-based research programme was commissioned to enhance the understanding of processes leading to physical and biological recovery of the seabed following dredging, thereby aiding the identification of practices to minimize environmental harm at licensed sites, and to promote rehabilitation on cessation. The outcome of survey work will have the notable benefit of allowing questions about the present status of locations hitherto subject to commercial exploitation to be answered directly, rather than by inference.

Jan 1, 2002

By Tim J. Boyd

Gregg Marine, Inc. (headquartered in Signal Hill, California) has recently introduced an innovative seafloor drill system for offshore geotechnical site investigation and seafloor mineral exploration. The system is capable of working in water depths of up to 3,000 meters and is rated to drill to a depth of approximately 150 meters below mudline. The remote operated system integrates established drilling technology with proven Schilling telemetry and controls. The flexible nature of the patented wireline drilling technology enables the use of standard sampling systems (up to PQ-size core and 3? thin-walled tubes) as well as downhole testing systems (including CPT testing, vane shear testing, downhole sensors and borehole geophysical tools). The modular nature of the seabed drill system and the accompanying launch and recovery system (LARS) enables the use of local vessels of opportunity for projects resulting in reduced project costs and improved mobilization responsiveness times. Keywords: seafloor, seabed, geotechnical, drill, drilling, core, coring, sampling, CPT, cone penetration testing, borehole, logging, survey, exploration, ROV, remote sensing

Jan 1, 2011

By Tetsuo Yamazaki

Manganese nodules on deep ocean floors have continuously received attention as potential sources for strategic metals such as Co, Ni, Cu, and Mn, due to their vast distribution and relatively higher metal concentrations (Mero, 1965; Cronan, 1980). Several registered Pioneer Investors have already identified promising sites in deep-sea regions for manganese nodule mining (ISA, 1998), and appropriate mining technologies have been developed during the last thirty years by the international consortium and several nations (Welling, 1981; Kaufman et al., 1985; Bath, 1989; Charles et al., 1990; Yang and Wang, 1997; Yamada and Yamazaki, 1998; Hong and Kim, 1999; Muthunayagam and Das, 1999). The mining feasibility for manganese nodules, including an economic evaluation, has been examined in detail by some researchers (Andrews et al., 1983; Hillman and Gosling, 1985; Charles et al., 1990; Soreide et al., 2001).

Jan 1, 2011

By Sven Petersen, Iain J. Stobbs, Bramley J. Murton, Paul A. J. Lusty

"INTRODUCTIONIt is widely thought that seafloor massive sulphide (SMS) deposits, the modern analogue of volcanogenic massive sulphide (VMS) deposits, present a potential global resource for base (Cu, Zn) and precious metals (Au, Ag). In addition, SMS deposits can be enriched in ‘critical metals’ including Se, Te, Tl [1], which are essential for use in the construction of modern and green technologies. Globally over 340 high temperature hydrothermal sites have been identified at a range of ocean spreading centres [2], significant massive sulphide deposit formation has been recorded at 165 of these sites [3].To date only 13 deep sea sulphide deposits have undergone intrusive investigation (drilling or coring) and of these, only 6 sites have published tonnage estimates [2]. Almost all research and drilling of SMS deposits has been focused on active systems, the investigation of the morphology, subsurface structure and mineralogy of hydrothermally extinct seafloor massive sulphide (eSMS) deposits is almost non-existent.As such, little is known about the mechanisms that operate post-SMS formation and which have an impact on the preservation and hence resource value of SMS. Identifying these generic processes and mechanisms, and the extent to which they impact the resource grade, is critical in evaluating the global potential of SMS."

Jan 1, 2017

By Raymond A. Binns

Drilling into an active hydrothermal system linked to convergent-margin felsic magmatism is a listed priority of the Ocean Drilling Program that addresses several fundamental geoscience issues. Solid and fluid products of felsic rock-water interaction, and the consequences for global chemical fluxes and for ore deposition, should differ from those in basaltic mid-ocean ridge environments already successfully tested by Legs 106, 139, 158 and 169. So, too, will fracturing controls on fluid pathways, and sources for metals and ligands. Researching the subsurface volcanic, structural/hydrologic, and mineralisation/alteration architecture of a drilled felsic-hosted system also has economic implications, especially for land¬based mineral exploration. A first-order hypothesis to be tested states that fluids derived from volatile-rich magmas are more important than recirculated seawater in convergent-margin hydrothermal systems - economic geologists increasingly appeal to this for creating "world-class" massive sulfide orebodies. Another hypothesis proposes "subhalative" massive sulfide deposition within hydraulically expanded volcanic products as a factor in generating large orebodies. Many second-order hypotheses such as leaching fractionated volcanics to cause gold enrichment in back¬arc systems also need testing. The thoroughly surveyed, active, PACMANUS hydrothermal field in the Eastern Manus back-arc basin of Papua New Guinea will be the site for ODP Leg 193 commencing in November 2000. It lies near the crest (1655-1750 m) of high-standing Pual Ridge, a 40 km-long edifice of dacite/rhyodacite with basal andesite all having geochemical and isotopic affinities with modern arc volcanoes of nearby New Britain. PACMANUS includes at least three focussed, high-temperature "smoker" sites with Cu+Au-rich massive sulfide deposits, and a field of diffuse, lower temperature venting through intensely altered dacite where modelling indicates significant subsurface mineralisation. Isotopic characteristics of deposits and vent fluids suggest magmatic contributions to the mineralising fluids.

Jan 1, 2000

By Delphine Pierre, Jean-Marie Augustin, Anne-Sophie Alix, Charline Guérin, Cecile Cathalot, Yves Fouquet, Arnaud Gaillot, Ewan Pelleter, Carla Scalabrin, Florian Besson

With the world’s growing demand for metals, seafloor massive sulfides (SMS) deposits are now seen as a possible mineral resource that could contributes to secure metal supply for human needs. SMS deposits are characterized by high concentrations of base metals and at some place high contents of precious and rare metals. Since 1977 and the discovery of the first high temperature (HT) hydrothermal vent and its sulfide mineralization and high biodiversity, more than 300 sites are known today. If the exploration strategy for detection of active hydrothermal sites is now robust, their associated mineralization will not (and must not) constitute a potential target for deep-sea mining due to environmental concerns and technical limitations. Recent studies on SMS deposits are rather focused on extinct and buried mineralized sites characterized by a lower biomass. Several geophysical techniques to explore and detect extinct SMS (eSMS) and buried SMS (bSMS) have been developed (e.g. Kawada and Kasaya, 2017; Szitkar et al., 2017, 2014) using different approaches (e.g. regional or local scale; ship-based or using underwater vehicles) with several degrees of success or limitation. Here we present results from acoustic surveys performed on the TAG hydrothermal district during the BICOSE (2014) and LEVE-SMF (2016) cruises and direct observation provided by HOV (Nautile) dives carried out during HERMINE cruise (2017). Acoustic data were acquired using two different multibeam echosounders (MBES): the hull-mounted Kongsberg EM122 (12 kHz, R/V L’Atalante) and the ROV-mounted RESON SeaBat 7125 (400 kHz, ROV Victor) (Figure 1). After processing, acoustic seafloor backscatter data from both MBES provides complementary qualitative results in relation to the seafloor composition. The analysis of the seafloor backscatter data obtained by near-seafloor surveys with the high-resolution 400 kHz MBES shows a clear relationship between low backscatter strength values and areas covered with pelagic and hydrothermal sediments whereas high backscatter strength values are associated to pillow lavas and basaltic scree. Intermediate backscatter strength values are rather related to old and younger eSMS as well as to mineralization on TAG active mound.

Jan 1, 2018

By Sang-Mook Lee

The Manus back-arc basin behind the New Britain Trench is one of the major sites of active seafloor hydrothermal vent-fields which are considered to be modern-day analogue of felsic volcanic-hosted polymetallic massive sulfide deposits abundant in ancient geological record. Many of these deposits represent multi-million dollar resources, and yet very little are known about the fundamental processes leading to their formation. In November 2000 January 2001, the PACMANUS hydrothermal system in this region will be targeted by the Ocean Drilling Program Leg 193 to investigate the internal anatomy. A number of observations that suggest that the tectonic, magmatic and hydrothermal processes in the eastern Manus basin spreading center are unusual in that they can not be explained by a simple back-arc opening due to subduction of the New Britain Trench. Geochemistry of submarine volcanoes in the eastern Manus basin, for instance, shows affinity to arc rather than back-arc type volcanoes. Yet these submarine volcanoes lie too faraway from the Benioff-Wadati zone. One hypothesis is that the magmatic and subsequent hydrothermal activity of this region is a direct result of the irregularities in the deep crust and upper mantle structure and that the tectonic process is controlled by the sharp inflection of the New Britain Trench. According to this hypothesis, the two major southeast-trending strike-slip faults in the eastern Manus Basin, Djaul and Weitin Faults, should extend farther down and join to the New Britain Trench. They would form a transform arm of the triple junction with the New Britain Trench southeast of New Britain Island and southwest of Bougainville Island forming the other two arms. A trench-trench-transform triple junction can not be stable over time, and therefore a slight change in the plate velocity may lead to a dramatic change in the configuration of the plate boundaries. If so, the instability of the triple junction may cause large tectonic deformations, such as mantle uplift under the Manus basin due to mantle rupturing by transform faults, and therefore may explain the arc-style volcanism and unusual compositions of hydrothermal deposits in the eastern Manus basin.

Jan 1, 2000

By Irina Melekestseva

The Cu-Zn massive sulfides from the basalt-hosted Semenov-2 hydrothermal field (13°31.13´ N, 44°59.03´ W, MAR) are enriched in Au (22?188 ppm) and Ag (127?1787 ppm) [Ivanov et al., 2008] and elevated contents (ppm) of Se (269?289), Sn (123?125), and Sb (72?75). These may indicate heterogeneous substrate rocks and possible ultramafic rocks. Based on phase analysis, 70% of the gold in the massive sulfides is free. LA-ICPMS analysis has shown that the main carrier of the invisible gold is covellite (22.51? 226.64 ppm). Covellite is also characterized by elevated contents of Se, Mo, Sn, Te, Au, Bi, As, Ag, Sb, Tl, and Pb relative to the primary sulfides.

Sep 14, 2011

By Robert G. Ditchburn

Msjflkcisokng During the past sixteen years, GNS Science has developed a number of radiometric methods for dating massive sulfide samples from submarine arc and back-arc volcanoes. This has improved our understanding of the formation of these hydrothermal systems, the frequency and duration of their activity, and assisted marine mineral exploration companies in assessing the economic potential of these deposits that can be rich in copper, zinc and gold (up to 90 ppm Au in some chimneys). The radiometric dating methods that we employ utilize radium isotopes that are extracted from the host rocks without their parent thorium isotopes, by ascending, hot, acidic hydrothermal fluids. When the hydrothermal fluid discharges into cold seawater, chemically similar barium and radium co-precipitate as barite, a common mineral contained within the black smoker chimneys that grow upwards from the seafloor. From the onset of mineralization, the isotopes 228Ra and 226Ra (with half-lives of 5.75 yrs and 1600 yrs, respectively) begin to decay, so that the 228Ra/226Ra and 226Ra/Ba values decrease with time. Thus, samples can be dated using these ratios once the initial values, i.e., the values at the onset of mineralization, have been established, ideally from active chimneys. 228Ra decays to 228Th (half-life 1.91 yrs) and from the 228Th/228Ra values, the growth-rate of individual chimneys can be estimated. The isotope 210Pb (half-life 22.3 yrs) is occasionally used for dating the mineralization, although several samples from a chimney are needed to determine an age from the 210Pb grown from 226Ra, using the isochron technique.

Sep 14, 2011

By James R. Hein

Barite and Fe-Mn-oxide deposits that occur along faults in the Southern California Borderland formed by low-temperature hydrothermal processes. The Borderland region consists of block-faulted continental crust within the broad transform boundary of the North American plate. The fault-bounded basins are anoxic and partially filled with hemipelagic and turbidite sediments. Barite was collected from four dredges and a submersible dive (DSV4-355) in the southern California Borderland, and was collected from two sea-cliff sites along the Palos Verdes Headlands near Los Angeles. Barite at these seven locations occurs along strike-slip and basin-margin faults from the shoreline to 1800 m water depth. Submersible observations showed a series of mounds up to 10-m high composed of friable, white barite associated with diffusely venting milky fluid; the mounds support large benthic colonies, including tube worms (Lonsdale, 1979). Barite samples recovered from dredges are brown, green, and white and range from porous, vuggy fragments to massive fragments cut by banded barite veins. Samples from two dredge sites contain fossil worm tubes 1-3 mm in diameter and >10 cm long. All the samples are nearly pure barite, with only minor to trace amounts of other minerals. Chemical analyses show 94-98 wt. % BaSO4, low total rare-earth element (REE) contents (<45 ppm), Sr contents from <2 to 10,000 ppm, and Hg contents up to 1 ppm. Chondrite and shale-normalized REE patterns show light REE enrichments and large positive Eu anomalies. These REE pattern characteristics are typical of marine hydrothermal fluids and minerals. Sulfur isotope ratios (d34SCTD) from +21.6 to +67.4? range from seawater values (+21?) to exceptionally high positive values. Strontium isotope ratios are lower than the modern seawater ratio as well as the seawater ratio that existed at the time of deposition of the host rocks.

Jan 1, 2002

By David S. Cronan

The traditional method of deep sea manganese nodule exploration is to conduct grid survey and sampling on successively finer scales until a suitable deposit has been delineated. Clearly this is both time consuming and ultimately self-defeating if large areas of the ocean floor are to be explored on a human timescale. A conceptual deductive approach would be preferable if one could be found, as it would aim to outline areas of potentially economic nodules on the basis of easily measurable oceanographic parameters. An attempt to achieve this aim in the Central Pacific is outlined below. Nodule Distribution in the Central Pacific Ocean Maps of ore grade nodules in the Central Pacific show that they are confined to two zones trending roughly east-west which are well separated in the eastern Pacific but which tend to converge towards 170-180ºW. They follow the isolines of intermediate biological productivity in the surface waters, strongly suggestive of a biological control on their distribution. Within these zones the nodules preferentially occupy basin areas. Thus they are found in the Penrhyn Basin, Tokelau Basin, Central Pacific Basin, Clarion Clipperton Zone and Tiki Basin. Nodules in all these areas have features in common and are thought to have obtained their distinctive composition by similar processes.

Jan 1, 2003

By Arturo Carranza Edwards

Sedimento II oceanographic cruise, on board of the B/O El Puma, shows a new high anomaly or phosphate associated with shelf sediments from the south Mexican Pacific. Recently, were found two anomalies in the Gulf of Tehuantepec, that are located to the east of this new anomaly, that is related to muddy sands and rock fragment debris. The latter shows values of 17% P205. The phosphate occurrence is probably associated with red tides locations that usually are found in sites where sediments are phosphates enriched. These findings suggest that south Mexican Pacific is of potential interest for P205, in waters with high nutrients values. The possibility of a more regional occurrence of phosphate, from California to Chile is suggested.

Jan 1, 2000

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