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By Pierre-Yves Morvan

One of the numerous challenge for underwater mining is the positioning. This paper describes an architecture for the integration of an Ultra Short BaseLine (USBL), an Acoustic Synthetic BaseLine (ASBL) operating in Sparse Array mode and a Doppler Velocity Log (DVL) closely coupled with an Inertial Navigation System (INS) for precise subsea positioning in severe environments. By using such architectures, the INS can help to reduce the noise on the measurements coming from acoustic sensors. Another advantage is the capability to reduce the number of required transponders on the seabed, and as a consequence, reduce the time for the deployment and calibration of each transponder. The paper further describes sea-trials performed to assess the ability of a complete positioning system to provide decimetric positioning precision even with a single beacon deployed in the navigation area.

Jan 1, 2017

By Alan Foley

The Portable Remote Operated Drill was developed in Sydney, Australia in the 1990’s. The device is a platform for many in-situ seabed sampling and coring tasks. The range of tools developed for use in PROD’s magazine now includes gas detectors, vane testers, penetrometers and corers. This paper presents aspects of the soils testing undertaken in deepwater since 2005, focusing on testing of methane hydrates and reefal accumulations. The varied selection of tools carried in PROD’s magazines allow the unit to perform several functions from the seafloor in one deployment.

Sep 24, 2006

By Eric J. Foell, Hjalmar Thiel, Gerd Schriever

Environmental studies for the mining of polymetallic nodules (PN) from the deep sea may be traced back for some 35 years.

By J. R. Woolsey

The cost of an offshore exploration project is mainly dependent on the size of the vessel engaged for the work and increases dramatically with increasing size. Of the various factors influencing vessel size, the type and size of the sampling equipment is typically the principal consideration. This scenario is particularly true of shallow sampling programs employing a vibracore system. The problem develops when certain bottom materials such as densely packed fine sand require sampling. This type of material being one of the most difficult for the standard vibracore systems, with integral core liner, to penetrate to a reasonable depth of some five to seven meters. The problem is mainly related to the excessive cross sectional area of the cutting bit required to accommodate the core liner. The typical solution has been to apply more power to the vibracore drive head which results in a considerable scale-up for the entire system with attendant increase in vessel size. In order to reduce operating cost, M.M.R.I. has developed several systems for deployment from vessels in the 20 meter range. Two systems are modifications to the basic vibracore and a third is a vibralift system. Basically, one of the vibracore units is employed where core liners are required, utilizing a special jet bit designed to reduce the cutting pressure on the bit while not affecting the integrity of the core. The other designed for core extrusion on

Jan 1, 1986

By Harry J. Olson

Geothermal Energy has a great potential for meeting the electrical and thermal energy requirements of many countries and territories lying along tectonically active zones within and surrounding the Pacific Basin. Energy requirements for many of these small, scattered volcanic island nations preclude development of conventional generating facilities large enough to incorporate any economies of scale. However, by attempting to discover and develop shallow, relatively low temperature, geothermal reservoirs associated with recent vulcanism on many of the volcanic islands, exploration expenditures and risks, and problems associated with the development of high temperature resources can be reduced. Exploration and development drilling for these resources can be accomplished with truck mounted rotary drilling rigs that are less costly and more suitable for operations within the island infrastructures than the conventional rigs normally used in the drilling of deep, high temperature geothermal resources. Experience over the past decade with small, modular, binary (Rankine) cycle generating units indicates that geothermal energy can provide a reliable source of baseload electricity in the amounts required and at a cost that is competitive with other alternative and conventional energy sources. Development of shall, moderate temperature, geothermal resources with small, modular binary cycle generating units can provide ideal additions to the energy sources of many of the Pacific volcanic island nations within the framework of their island economies.

Jan 1, 1991

By James C. Barker

Alaska's expansive continental shelf represents future opportunities for marine mineral development. Although today's metal prices and subsidized foreign mineral production continue to discourage industry investment in marine exploration worldwide, the longer term outlook is one of increasing costs on-shore with a dwindling land-base available on which to search for and extract minerals. Likely, the generations of the 21st century will increasingly recover their minerals from the sea-floor. Though largely unexplored, Alaska potentially represents a major port ion of the U.S. marine resources. Several factors demonstrate this. First, the Alaskan OCS is huge; 74% of the entire United States' continental shelf lies off of Alaska, and 54% of the U.S. coastline is Alaskan. Combined with the jurisdiction waters of the Soviet Far East, the Bering-Chukchi shelf is one of the world's largest tracts of shallow water. Second, Alaska is situated at the northwestern terminus of the mineral-rich American cordillera. From Chile to Alaska, major on-shore deposits of precious and base metals, ferroalloys, and industrial minerals are found in the tectonically disturbed belts of the cordillera. In 1988, the western U.S. cordilleran states produced 70% of this country's mineral output (excluding construction materials). Throughout the cordillera's entire 10,000 mile length, the rock units strike largely parallel to the coastline, but in Alaska they extend directly offshore and onto the continental shelf. Consequently, the mineral-rich terranes off of Alaska have a much more complex interaction with coastal and lit-

Jan 1, 1991

By M. Geoghegan

Under the provisions of the U.N. Law of the Sea Convention Ireland is likely to have mineral rights to an area of continental shelf some six times its present land area. Apart from the major potential hydrocarbon basins which are currently the focus of active commercial exploration, little is known about the mineral resources of this vast area. In recent years a variety of mineral resources however have been identified from the coastal region. These include Sand and Gravel aggregates, Calcaraeous Algae (Lithothamnion), Heavy Mineral Sands and Coal deposits. The potential also exists in the coastal zone for buried placer deposits and base metal deposits. Several million cubic metres of gravel and hundreds of millions of cubic metres of sand have been identified by the Geological Survey of Irelands (G.S.I) Marine Unit off the east coast. The greater part of these deposits lies within the 10 metre depth contour and are easily recoverable. Irish aggregate needs at present are well supplied by onshore Pleistocene glacial deposits. Commercial interest in offshore deposits is in supplying coastal areas which are locally poor in aggregate and major coastal construction works. The possibility of supplying the large British and Continental European Market nearby also exists.

Jan 1, 1988

By Chris Castle

Following the recent award of a prospecting license by the New Zealand Government, Widespread Energy Ltd. (Widespread) is focused on the acceleration of its exploration program in order to bring a potential phosphorite deposit to market in the near future. Rock phosphate is the primary constituent of most fertilizers that are manufactured and distributed in New Zealand. Field trials in the 1980s demonstrated that direct application of rock phosphate can result in a more effective fertilizer (than super-phosphate) with less environmental damage from run-off. At present virtually all of the rock phosphate used by the New Zealand fertilizer industry (approximately 1 million tonnes a year) is imported from Morocco. In recent years price increases of up to 12 fold (peak of $500/t) with massive increases in freight costs have bought to the forefront the economic opportunity to in part replace foreign imports with a local source of phosphate. The Chatham Rise phosphate deposits are relatively well understood, having being discovered during the 1950?s and it is estimated that approximately 100 years supply (at current requirements) is present at shallow depths. An estimated 100 million tonnes of rock phosphate is present within the license area based on previous private and publicly funded research. Widespread has engaged several parties to assist in the exploration planning to confirm the resource potential. Widespread has commenced investigating the feasibility of recovering the phosphorite nodules off the sea floor, and presently has several conceptual technical solutions under consideration and will advance the discussions with potential contractors during the exploration phases. Widespread is acutely aware of its responsibilities to conduct both the exploration program and extraction of the rock phosphate, in a manner that causes minimal disruption to the marine environment. To this end, the National Institute of Water and Atmosphere (NIWA) ? a New Zealand Crown Research Institute has been engaged to assist in designing sampling and extraction methods that will minimize disruption to the seabed. All sampling and extraction activities are planned to be conducted with reference to the environmental guidelines published by the International Marine Minerals Society ?Code for Environmental Management of Marine Mining.? Widespread is conducting its project with a background of changing regimes to both the allocation and environmental management of its activities.

Jan 1, 2010

By P. Mikhailik

Recently, characterized by fast development high- and nano-technology, demand for rare and trace metals has increased. One of such metals is gallium. Gallium compounds, mainly GaAs, are used in medicine, to manufacture optoelectronic devices, microwave techniques, devices of solar power and infrared optics, etc. The basic gallium industrial deposits are known only on land. There are bauxites (50 ppm), nepheline rocks and ores (36-38 ppm, minerals concentrators are nepheline and sodalite), Zn-Pb-Cu ores (5000-12000 ppm, minerals concentrators are gallite, germanite, sphalerite, bornite), sulphide-polymetallic and Pb-Zn ores (10-32 ppm, minerals concentrators sphalerite, chalcopyrite) (Vershkovskya et al., 1998). High concentration of gallium are observed in hydrothermal massive sulphides of a Mid-Okinawa Trough (The South Chinese Sea) and Sujo seamount (The Philippine Sea) (Noguchi et al., 2007). As it is known, deep-sea massive sulphides and associated Fe-Mn crusts are products of hydrothermal fluid discharge. High-temperature massive sulphides precipitation are the first, and low-temperature Fe-Mn crusts deposition is the last process of hydrothermal mineralization (Cronan, 1982). Hydrogenic crusts and nodules of the World ocean are characterized by low concentration of Ga, close to clarke (19 ppm) (Kobaltbogatye.., 2002). Hydrogenic crusts from the Sea of Okhotsk are exception, because Ga concentrations are exceeded clarke in 3,5 times (Mikhailik, et al., 2009). Complex studying of Fe-Mn crusts from deep-sea basins volcanic seamounts of the Sea of Japan has shown their hydrothermal-sedimentary genesis (Mikhailik, 2009). High gallium concentration (up to 850 ppm) was established in these crusts by ICP-MS (Agilent 7500C). Microprobe research (JXA-8100) of samples Fe-Mn crusts has not revealed the gallium minerals concentrators. It suggests that, gallium in Fe-Mn crusts of the Sea of Japan is sorb substance.

Jan 1, 2010

By Jung-Keuk Kang

Recently, the Korean government prepared a strategy for deep seabed mining, which consists of three stages for 20 years until 2010. The first step of the program is focused to conduct deep seabed exploration until 1993. The apparent "hurry-and-spend to catch-up" policy that the Korean government has shown in deep seabed mineral exploration was motivated by an effort to qualify a prerequisite requirement to be a pioneer investor as a developing country under the terms of Resolution II and the New York Understanding. Since 1983, KORDI (Korea Ocean Research and Development Institute) under the auspices of the Korean government has carried out deep seabed mineral exploration. The KORDI had a joint exploration program with USGS from 1989 to 1991 aiming to evaluate the potentiality of manganese nodule in the western part of Clarion-Clipperton Zone as well as that of manganese crusts in the western Pacific. In 1992, Korean government accelerates its program by the confirmation of national policy and the equipment of new built research vessel, Onnuri-Ho. The RIV Onnuri-Ho is about 1400 G/T, which is equipped with various advanced instruments including GPS, multi-beam echosounder (Seabeam 2000), multi-channel seismic system, and MDM system.

Jan 1, 1992

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 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 Teruyoshi Narita

In Japan, the Ministry of Economy, Trade and Industry (METI) commenced a research and development (R&D) project on seafloor massive sulphides (SMS) in Japan?s exclusive economic zone (EEZ) in the 2008 fiscal year. In this plan, the road map of Resource evaluation, environmental impact study, mining system technology and processing technology fields consisting of the first and second stage has been shown for the commercialization of SMS. Based on this road map, Japan Oil, Gas and Metals

Sep 14, 2011

By Kris De Bruyne

Since 2013, GSR has undertaken 4 exploration campaigns, which focused on environmental baseline monitoring (marine biology), resource definition and technological change. The seabed nodule collection vehicle has a significant influence on the achievable production rate and is for that reason thought to be a serious risk in developing an economical viable mining operation. GSR is currently working on a pre-prototype of a seabed nodule collection vehicle. The program, called ProCat, started in 2015 and will take up to end of 2019. ProCat can be split up in 2 phases: ‐ ProCat#1 [2015 – Q2 2017]: separate parallel testing of the nodule collection- and driving mechanism (Tracked Soil Testing Device Patania I – TSTD Patania I). The trafficability was tested in-situ; the collection mechanism was tested in a laboratory. Phase 1 has been completed successfully in September 2017. ‐ ProCat#2 [Q3 2017 – end of 2019]: the knowledge acquired during the first phase was used in this 2nd phase. Both collection mechanism and driving mechanism were integrated into the design of a pre-prototype seabed nodule collection vehicle (Pre-Prototype Vehicle Patania II – PPV Patania II). This pre-prototype vehicle will be used for a simulated mining test in Q2 of 2019 in the GSR- and BGR license area. The main objective of the ProCat research program, and especially the 2nd phase, is to integrate the nodule collector on the tracked chassis and develop an operating vehicle causing minimal environmental impact hereby validating the requirements for a full scale polymetallic nodule collection vehicle in the actual operational environment of the CCFZ. Following the ProCat project, GSR is working towards a system-integrated mining test once exploitation regulations have been agreed by the ISA and its member States.

Jan 1, 2018

By Leonhard Weixler, Peter Platzek

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

Jan 1, 2018

By W. C. Burnett

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

Jan 1, 1986

By G. A. Gross

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

Jan 1, 1985

By Christian Müller, Hermann-Rudolf Kudrass, Christian Reichert

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

Aug 24, 2006

By Kyung-Ho Park

The smelting leaching process is known as one of the most favorite methods for the processing of deep-sea manganese nodules because of its smaller environmental impact and easiness of manganese recovery. The sulphuric acid pressure leaching of the matte prepared from deep-sea manganese nodules was studied to dissolve the valuable metals. Almost complete dissolution of Cu, Ni, and Co from matte was achieved under the following conditions: leaching temperature 180°C, time 4 hours, PO2 10 kgs/cm2, acid concentration 2.5% (vol/vol), pulp density 5%, ammonium sulphate 40 g/l. Under these conditions the iron concentration of leach liquor was 0.95 g/l. Optimization of leaching parameters was carried out by statistical design of experiments using 23 full factorial matrix. The linear and interaction co-efficients were evaluated for dissolution of metal values and also for iron concentration in leach liquors.

Jan 1, 2003

By Thomas Kuhn, Anna Wegorzewski

"INTRODUCTIONPolymetallic nodules from the Clarion and Clipperton Zone (CCZ) within the equatorial NE Pacific Ocean show high concentration of economic important strategic metals such as Ni, Cu, Co, Mo and Rare Earth Elements (REE). The content of those metals in nodules is depending on (i) the supply during individual growing periods, (ii) the environment conditions as well as (iii) on different manganese minerals, which occur in nodules. The incorporation of the metals can vary within the structure (incorporated into the structure / over vacancies of the structure) and this can be relevant for the further metallurgical treatment.Mineralogy of Mn-nodules from the CCZ and the incorporation of metalsManganese nodules consist of nm to µm thick layer growth structures (LGS) of different genetic origin (hydrogenetic/suboxic-diagenetic). Those LGS form due to the precipitation of Mn-and Fe-(oxy) hydroxide colloids from the oxygen rich near-bottom water and/or pore water (hydrogenetic growth; Halbach et al., 1988) or from suboxic (depleted in O2 <5µmol O2/l; Hein and Koschinsky 2013)) near-bottom water/pore water (suboxicdiagenetic growth; Halbach et al., 1988; Wegorzewski and Kuhn, 2014).In general, metals dissolved in seawater will be adsorbed and complexed on the oxide surfaces according to their different surface charge. The surface charge of the Mn-Fe (oxy) hydroxides depends on the pHzpc (zpc: zero point of charge). In seawater dissolved hydrated cations (Ni2+, Cu2+, Co2+) are adsorbed preferentially on the negatively charged Mn-oxide (MnO2 -) surface (pHzpc 2.8). In contrast, negatively and neutrally charged complexes (e.g., Ti(OH4); REE(CO3)2 -, MoO4 2-) are adsorbed on the surface of Fe-oxy hydroxide colloids (FeOOH+) which have a slightly positively charged surface (pHzpc 8.5; Stumm and Morgan, 1981; Koschinsky and Halbach 1995)."

Jan 1, 2017