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By B. Prause

Ferromanganese crust samples collected from Central Pacific sea-mount areas became of special interest after surprisingly high nobel metal contents have been analyzed. Hydrogenetic crust growth is controlled by the conditions of the oceanic water column. Thicker encrustations show two crust generations of different age ranges. The mean values of the chemical composition state that the older generation is richer in P, Ca, Ni, Cu, Zn, and Pt and depleted in Fe, Ti, Co, Al, and Si. The differences apparently indicate a distinct change of the geochemical environment. The Pt concentrations vary up to 1800 ppb and do not clearly correlate to one of the other metals. This might indicate a bond of multiple nature. Several mechanisms have been proposed to explain the Pt concentrations in ferromanganese samples. Our models consider seawater and cosmic spherules as responsible Pt sources. In seawater the main species of dissolved Pt probably exist as the doubly negatively charged tetrachloro-complex. A precipitation of Pt in seawater may take place if the chloro-complex is decomposed by reduction of pt2+ to pt0. On the other hand, the Mn02 precipitation is caused by an oxidation of Mn2+ which is supplied from the oxygen-minimum zone. The large activation energy needed for the oxidation of divalent ~n" in solution has been recognised, and the resulting slowness in the formation of Mn(V1)-oxihydrate sug

Jan 1, 1989

In 1983, the GEMINO research project (Geothermal Metallogenesis Indian Ocean) was initiated in order to locate and evaluate sites of recent or fossil hydrothermal activity in the largely unexplored Indian Ocean. During GEMINO cruises 1 and 2 with R/V SONNE in 1983 and 1986, the Central Indian Ridge between 21°S and 24°S was the subject of detailed exploration, including SeaBeam and magnetic mapping, hydrocasts, sediment coring, TV-grab sampling, and camera/video tows. Although hydrothermal sulfide mineralization was not located, a hydrothermal component in the sediment composition, hydrothermally altered basalts, and maximum concentrations of 27.5 nmol/kg Mn and 45.6 nl/l CH4 were discovered (Plüger and Herzig 1986; Herzig and Plüger 1988a). Leg 1 of the GEMINO-3 cruise in 1987/88 identified a neovolcanic ridge in the rift valley of a 30 km segment at 22°55'S as a site of weak hydrothermal activity and photographed smectite-like precipitates on basalt talus and a chimney structure on top of a ridge-parallel fault scarp. Water temperature data and the distribution of Mn and CH4 were interpreted as indicative of diffuse, low-temperature hydrothermal activity (Herzig and Plüger 1988b).

Jan 1, 1989

By Gordon B. J. Fader

A regional assessment of the aggregate potential of the Scotian Shelf is presently being funded through a Canada-Nova Scotia Cooperation Agreement on Mineral Development. This assessment includes testing of seabed materials for their suitability in a variety of concrete, asphalt and other specialized applications. The glacial and postglacial Holocene history of the Scotian Shelf has been favourable for the formation of large deposits of sand and gravel that have potential for use as marine aggregate resources. Large banks and inner shelf areas of the seabed consist of basal transgressive sand and gravel of the Sable Island Sand and Gravel Formation. These sediments accumulated during the late Wisconsinan postglacial transgression, through sorting of glacial materials that were originally deposited beneath marine terminating glaciers. Some sandy deposits occur as low-stand deltas on the inner shelf at 70 m water depth and were formed during the maxi- mum low sea level stand, in early postglacial time, at approximately 12 000 yBP. Modern sediment transport processes have contributed to the formation of areas of large sand bedforms, such as the Cape Split sand wave field and other isolated sand waves of the inner Bay of Fundy, and Eastern Shoal on Banquereau. Sandy sediments, found in many transverse channels in the nearshore, offer a potential for placer gold where proximal to adjacent onshore epithermal gold deposits. Lithothamnion covered gravel occurs as a thin lag overlying glacial sediments in much of the nearshore. Relict gravel beach ridges have been eroded and redistributed through sub-littoral processes after passage of the transgressing beach front. Multibeam bathymetry, sidescan sonograms and high-resolution seismic reflection profiles are the main survey tools. Ground truth consists of large volume seabed samples, vibrocores and photographs. A preliminary assessment of the aggregate potential indicates that very large volumes of suitable aggregate lie in the offshore of southeast Canada.

Jan 1, 1995

By Frank Manheim

The purpose of this presentation is to review the history of offshore non- fisheries resource development since World War II, as an introduction to a planned symposium on offshore resources scheduled for the 1996 UMI Conference. After World War II the United States became the leader in offshore oil and gas production, deep ocean drilling technologies, offshore terminals, platforms and production systems, and natural gas recovery and transport. Wartime skills in acoustic profiling and antisubmarine warfare were transferred into commercially important geophysical exploration techniques. The application of ocean drilling and geophysical techniques permitted the recognition and elucidation of plate tectonics patterns, development of seafloor spreading theory, and the transformation of our knowledge of seabed and subseabed strata. After John Mero's studies and recommendations for developing marine manganese nodules in the late 1950's interest in nonfuel minerals grew rapidly. The formation of international deep sea mining consortia in the 1960's was accompanied by a flurry of ocean engineering development, minerals prospecting and associated environmental studies The Santa Barbara Oil Spill of 1969 resulted in a moratorium on both offshore energy and minerals leasing by the Depart- ment Interior, and catalyzed the development of new Federal legislation in 1972. In 1973 the offshore energy moratorium was lifted in response to the Arab oil embargo, and offshore energy activities surged for a time. Minerals were reopened to leasing following President Reagan's 1983 executive order implementing a 200 mile EEZ. Although interest was spurred by

Jan 1, 1995

By Ivar Eskerud Smith, Ole Jørgen Nydal, Niranjan Reddy Challabotla, Svein Sævik

INTRODUCTION Airlift pumping, utilize compressed air that is injected at the bottom of a vertical pipe submerged in the water, reduces the mixture density inside the pipe and lifts the liquid or mixture of liquid and solids. This type of pumping technology, which is simple and without moving parts submerged in water, which provides several advantages compared to the mechanical pumping. Airlift is used in various difficult pumping applications such as transport of fluids corrosive to metals, explosives, nuclear and toxic materials in chemical industries, diamond mining and coal transport. Application of airlift to deep sea mining conditions was investigated by extensive laboratory experiments [1], theoretical analysis [2], and limited proof of concept field studies [3] starting in 1970’s with the discovery of huge amounts of manganese nodules discovered on the seabed at a depth of ranging from 4000 to 6000 m . Even after extensive investigations over the last five decades, there exists no commercial application of airlift technology for lifting of minerals. The major problems with the application airlift for deep ocean mining was (a) lack of control over the expansion of the injected gas, which increases the velocity in upper part of the riser pipe (b) lower efficiency compared to mechanical pumping [3]. Different flow regimes are encountered in airlift pumping: bubble, slug, churn and annular flow. Annular flow regime is the least efficient in lifting of particles and churn flow has better efficiency [3].

Jan 1, 2018

By Timothy F. McConachy

Between April 2000 and April 2002, the Commonwealth Scientific and Industrial Research Organization (CSIRO) Division of Exploration and Mining has led 6 research expeditions totalling 160 days ship time in waters of Papua New Guinea, Vanuatu, Solomon Islands, Indonesia and Australia. Five expeditions were undertaken aboard the Australian research vessel Franklin following successful competitive research proposals, and the sixth used the Indonesian vessel Baruna Jaya VIII (see Table 1). In addition, two CSIRO participants joined JOIDES Resolution for the Ocean Drilling Program Leg 193 in the Manus Basin of PNG. The major scientific objective underpinning these expeditions was to locate and study present-day seafloor and sub-seafloor hydrothermal ore-forming activity in order to develop improved methods of exploring for ancient mineral deposits on land that originally formed by similar processes. The research has been supported financially by a number of Australian-based mineral companies, by Australian international aid agencies, and by appropriation funds from CSIRO, and was conducted in collaboration with researchers from Australia, Indonesia, Portugal, New Zealand, United States of America, South Korea, and the host nations. Building upon earlier successes in the 1986-1997 PACLARK-PACMANUS programs in the Woodlark and Manus Basins of PNG, we have sought to examine a wider range of geological settings in which ancient orebodies are inferred to have formed, including both volcanic and sediment-hosted environments. We have now visited volcanic arcs, fore-arc and triple-junction related submarine volcanoes, and back arc basins associated with convergent plate margins in the SW Pacific and SE Asia, as well as conceptual Mississippi-Valley-type targets associated with warm seeps at passive margins in the Great Australian Bight (see Figure 1). Surveys ranged from northern Sulawesi via far western Bismarck volcanic arc near PNG-Indonesia border, through the eastern Manus Basin and the Tabar-Lihir-Tanga-Feni chain in PNG, the western Solomon Islands festoon, the San Cristobal arc, parts of the Vitiaz arc, to the northern and southern New Hebrides arc in the Solomons and Vanuatu.

Jan 1, 2002

By Philomene Verlaan

Analysis of the relationship between environmental parameters and the content of Mn, Ni, Co, Cu, Fe and Zn in ferromanganese crusts permits improved identification of locations to prospect for crusts with commercially valuable concentrations of these metals. In this study we asked whether a statistically significant relationship exists between primary productivity of the overlying surface waters, the concentration of O2 in and depth of the O2 minimum layer on the metal content of non-hydrothermal ferromanganese crusts in the Pacific Ocean between 130o W and 175o E and 0o to 30o S (the study area). To further develop the interpretation of the results of the statistical analysis and to assess in detail the geographical expression of these parameters in terms of metal content in crusts, a geostatistical technique (kriging) was used to generate contoured values for metal content, primary productivity and O2 concentration in and depth of the O2 minimum layer in the study area.

Jan 1, 2001

By Jonguk Kim

Texture and geochemical composition of hydrogenous ferromanganese crust from relatively adjacent three seamounts (OSM2 at 157°35'E, 13°55'N, Lomilik at 161°37'E, 11°42'N and Lemkein at 165°05'E, 9°18'N) near the Marshall Islands in the western Pacific (Figure 1) were investigated in order to elucidate their growth history. These seamounts, located in different latitudes, are along a line that is parallel with the direction of Pacific plate movement. Thick crusts commonly have three or four distinct layers (Figure 2): (1) layer 1, uppermost layer, is black, dense, and has a botryoidal, columnar, or laminated texture; (2) layer 2, overlain by layer 1, is Fe-stained, porous to vuggy and filled with sediment; (3) layer 3, phosphatized layer, is black, massive, dense, and impregnated by CFA, (4) layer 4 shows parallel to undulatory laminated texture and cut by CFA-filled veins. Layer 1 and 2, unphosphatized young layer, are observed in crust samples collected from all seamounts. However, lower part of the crust shows different textures in different seamounts. Both layer 3 and 4 are found in thick crust from OSM2 but layer 4 is absent in crust samples from Lemkein and Lomilik. All the uppermost layers (layer 1) from three seamounts have similar textural and geochemical characteristics. Layer 2 is overlain by layer 1, is porous, partly Fe-stained, and sediment-infilled. In previous studies, layers 1 and 2 have grown in different oceanic environment. Textural and geochemical properties show that layer 1 has grown under relatively higher bottom water activity and lower productive environment than layer 2. Carbonate and detrital materials in layer 1 are not abundant compared to layer 2. Layer 2 can be assumed to have grown under equatorial high productivity zone (EHPZ) while layer 1 has started to grow when the seamount left from the EHPZ.

Jan 1, 2003

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 Andreas Kaede

INTRODUCTION Due both to the political history of UNCLOS and the sensitivity of the ocean floor and environment to man made impacts, both the Convention (including also the 1994 Amendment) and subsequent codification (such as the ISA draft code on Exploitation of Mineral Resources in the Area) put a focus on information about, and conveyance of, technology employed by interested deepsea mining companies, to inter alia the Authority and developing countries. In contrast, companies usually are (or by their nature should be) interested in safeguarding their technology and business secrets in order to secure unique selling propositions in a competitive environment. On the background of the meanwhile maturing regulatory régimes on deep sea mining, the presentation will look into some of the key regulatory provisions mirroring these apparently antagonistic interests, how the players involved could deal with them, and how they might in some cases be reconciled. Progress of Presentation The presentation will start by briefly examining some classical methods of protection of technology, such as patents, copyrights, and (not the least) secrecy. It will be found that some of the statutory means of protection due to their territorial character may face problems in being implemented in areas outside national jurisdiction, such as the Area, but that, thinking globally, they nevertheless retain much of their value for the purpose of protection. Depending on available presentation time, a model case may be used to illustrate the above – and also some of the following – findings.

Jan 1, 2018

By John C. Wiltshire

Hawai'i is surrounded by a series of potentially valuable marine mineral deposits. These include manganese nodules between Hawai'i and Mexico, cobalt-rich manganese crusts and phosphorites in the Exclusive Economic Zone around the Hawaiian Island Archipelago, Johnston Island and the neigh- boring island states and sand and gravel deposits off the main Hawaiian Islands largely in State waters. Hawai'i has an economy that is very narrowly based on the tourist industry. In an effort to avoid the difficulties coming from such a vulnerable economy, significant efforts have been made toward economic diversification. The State has set up a range of programs looking to find new industries. New ocean industries figure prominently among these efforts as Hawai'i is surrounded by ocean. Naturally, among new ocean industries the potential for new marine mineral industries is significant given that Honolulu is the only full service port in the Central Pacific and Hawai'i is in the middle of the mineral belt. The port of Honolulu is now being actively used by mineral exploration vessels of several countries and with the current number of ship visits varying from 10-15 per year, this puts several million dollars a year into the State economy. It helps to fulfill the State's goal of dynamic growth in the ocean sector of the economy. Nonetheless, a major marine minerals industry, particularly one which would involve processing of minerals in Hawai'i, is controversial in a State whose main source of revenue is tourist expenditures based on the image of a pristine environment. In addition to the perceived threat to the hotel and fishing industry, is the whole highly emotional debate concerning preservation and development. To complicate the issue further, the major interest in developing a marine minerals is currently largely from Korea and China rather than from domestic U.S. industry. On the other side of the debate is the fact that the State's economy is hampered by many low paying jobs and a lack of technical jobs. This is further exacerbated by the fact that lower paying jobs are held disproportionately by people of Hawaiian and Pacific Island ancestry. Naturally, this leads over time to a certain amount of resentment. The higher paying technical lobs associated with a minerals processing industry could help to alleviate this problem.

Jan 1, 1996

By Janine Lahr, Peter E. Halbach

The Manus Spreading Ridge is located within the EEZ of Papua New Guinea and lies in the Manus Basin ENE of the PNG Island and N of the Island New Britain. The divergent backarc spreading system is caused by the subduction of the Solomon plate in the South under the Bismarck plate in the North along the lineament of the New Britain trench. The rate of divergence is relatively high compared to other back arc spreading systems and amounts up to 12 cm/year [3]. Since submarine volcanism and associated hydrothermal circulation as important parts of the oceanic heat transfer system are also dependent on the rate of spreading, hydrothermal fluid venting and respective deposition of polymetallic sulfides can be expected there. In late 1985 first indications for hydrothermal activity were observed on a swell within the central rift valley of the Manus Spreading Centre during a photographic survey of the seafloor by an expedition of the Hawaii Institute of Geophysics with the American RV Moana Wave [1]. Detailed geological investigations including successful sampling were first carried out in June 1990 within the scope of the OLGA II research project (conducted by Prof. Tufar, Marburg) using the German RV Sonne equipped with a deep-sea television sledge and Tvcontrolled grab systems. Simultaneously a research cruise with the Russian RV Akademic Mstivlav Keldysh took place using the manned submersible Mir; the findings of the OLGA II cruise were immediately used for planning and organization of the Mir dives [3]. The massive sulphide samples which we used for our geochemical and mineralogical studies originate from the hydrothermal fields 1 and 2 and are from grab stations of the OLGA II expedition [4].

Sep 24, 2006

By Demoor Damien

"The exploitation of marine resources has enjoyed renewed interest with a completely new sector, that of the Deep Sea Mining of mineral resources in the seabed, that is now gaining momentum. Nevertheless, the significant environmental constraints represent a challenge for initiating these new activities, whether this is in terms of the knowledge of the concerned ecosystems or in terms of monitoring and minimizing the impact of these new activities. This paper presents 2 technologies that aim to respond to the expectations of the stakeholders in this area. The first consists of the real-time monitoring of installations/operations and their impact on the environment using the most modern underwater technologies and especially long-term deployment AUV based on AUV docking station solution and autonomous long term observatories. The second consists of a membrane allowing the confinement of an area, the reduction of the emission of particles in suspension and noise reduction.IntroductionDeep ocean environments have been explored since the mid-1800s. As the land-based reserves of hydrocarbons and minerals become depleted, increasing numbers of resourcebased projects are being proposed for shallow then deepwater environments. Two distinct resource sectors have recognized the potential commercial value of working in shallow and deepwater environments – Oil and Gas and now Mining."

Jan 1, 2017

By K. Vanstaen, K. M. Cooper, S. Ware, S. L. Boyd

Remediation and restoration of offshore marine habitats is a relatively new concept with attempts in European regions largely being instigated by requirements of various strategic directives including Article 2 of the Habitats Directive (1992), the EC Water Framework Directive (2000, Article 2 of the OSPAR Convention (1992) and the developing European Marine Strategy Directive. A field experiment to establish the practicality of various options for rehabilitating the seabed on the cessation of dredging has been successfully set-up. The purpose of this experiment is to investigate the practicality and effectiveness of gravel seeding as a potential restorative method which could be applied at marine aggregate extraction sites following cessation of dredging. Zone 2, within Area 408 (offshore Humber) was chosen as the experimental site as there is some evidence for persistence of sand which may have resulted from screening operations at this site.

Aug 24, 2006

By Darryl Thorburn

The Cook Islands are 15 islands located in the Southwest Pacific (between 8-23°S latitude and 156-167°W longitude). The total land area is about 200 km2. However, because its islands are widely scattered, the EEZ of the Cooks encompass an area about 2 million km2. The Cook Islands government exercises sovereignty and jurisdiction over its EEZ according to international law and convention as a member state under UNCLOS1. Accordingly, the Cook Islands government exercises full control over resources in its EEZ, including minerals on the seabed. Decision making on allocating licences for exploration and ultimate mineral recovery is by the Cook Islands government and will be set out in relevant statutes. Seabed minerals investigations within the EEZ of the Cook Islands and adjacent waters were first carried out by, USSR, US, and New Zealand research vessels in the late 1960 early 1970?s and indicated the presence of high concentrations of manganese nodules. This early work was followed by a number of Government funded surveys in and adjacent to the Cook Islands EEZ These surveys have identified a world class resource of manganese nodules within the Cook Islands EEZ (CI EEZ), containing significant

Sep 14, 2011

By K. Vanstaen, K. M. Cooper, S. Ware, S. L. Boyd

Remediation and restoration of offshore marine habitats is a relatively new concept with attempts in European regions largely being instigated by requirements of various strategic directives including Article 2 of the Habitats Directive (1992), the EC Water Framework Directive (2000, Article 2 of the OSPAR Convention (1992) and the developing European Marine Strategy Directive. A field experiment to establish the practicality of various options for rehabilitating the seabed on the cessation of dredging has been successfully set up. The purpose of this experiment is to investigate the practicality and effectiveness of gravel seeding as a potential restorative method that can be applied at marine aggregate extraction sites following cessation of dredging. Zone 2, within Area 408 (offshore Humber) was chosen as the experimental site as there is some evidence for persistence of sand which may have resulted from screening operations at this site.

By David A. Clague, James R. Hein, Robert W. Embley, Robert C. Vrijenhoek, Randolph A. Koski

We report preliminary results for a group of unique samples collected with MBARI’s ROV Tiburon on August 12, 2005. The samples were collected from the East Blanco Depression (EBD) diffuse-flow hydrothermal field, which was determined in a previous study to cover an area of at least 100 m by 80 m (Hein et al., 1999). The survey reported on here extends that field to more than 1500 m in an approximately N-S direction. The EBD, a pull-apart basin, occurs near the western end of the Blanco Fracture Zone (BFZ), which connects the Juan de Fuca and Gorda Ridge spreading centers (Fig. 1). The samples were collected from a waterdepth range of 3343-3380 m.

Aug 24, 2006

By Henk van Muijen, Jan Willem de Wit

1.1 Profile IHC Holland Merwede IHC Holland Merwede is world market leader in the construction of specialist dredging equipment and large-size custom-built offshore vessels. The clients of IHC Holland Merwede include major dredging companies, oil and gas exploration groups, offshore contractors and government authorities. IHC Holland Merwede is focused on the continuous development and innovation of technology to ensure maximum performance and efficiency of its designs and constructions supplied to the dredging and offshore industries. IHC Holland Merwede has a staff of approximately 2,000 at its locations in Hardinxveld- Giessendam, Kinderdijk, Krimpen aan den IJssel, Sliedrecht, Delfgauw, Goes, Hendrik Ido Ambacht and Heusden. Besides worldwide representations, IHC Holland Merwede has branches in China, Houston (USA), India, the Middle East and Singapore. 1.2 Mission IHC Holland Merwede’s mission is to optimize value by anticipating and satisfying its client’s requirements, with efficient advanced technology solutions. The group’s aim is to be consistently at the forefront of technology development, in the business sectors in which it operates.

By Cornel E. J. de Ronde, Alexander Malahoff

Six active Kermadec arc submarine volcanoes, located between 34°S and 36°30'S were mapped and sampled between April and July 2005, using submersibles Pisces V and Pisces IV aboard the mothership R/V Ka'imikai-o-Kanaloa. The purpose was to study the relationship between hydrothermal activity, formation of hydrothermal mineral deposits, structure of the volcanoes, and the biodiversity of life associated with the hydrothermal vents. Of the volcanoes examined, all showed evidence of hydrothermal activity, including metal-rich plumes and helium anomalies. Only two of the volcanoes, namely Brothers and Clark, showed chimneys and surficial polymetallic sulfide deposition. Hydrothermal venting at a water depth of approximately 1,650 meters near the base of the northwest caldera wall of Brothers volcano has produced a field of chimneys, up to seven meters high and discharging black smoker venting. Temperatures up to 300°C were measured from the active vents. Clark volcano has a double cone summit at a water depth of 875 meters. The shallowest cone has a near-summit hydrothermal vent field with five-meter tall venting chimneys with smaller structures around the periphery. Water temperatures of 200°C were recorded for these chimneys.

By Hal Palmer

A number of Articles contained in the United Nations Convention on the Law of the Sea III (UNCLOS) bear directly on legal issues related to the recovery of mineral deposits on the ocean floor. Mineral resources of the continental margin other than oil, gas and hydrates include, sand, gravel, shell, coral, gemstones and phosphorite. Jurisdiction over the exploration and exploitation of these deposits is determined either by the Territorial Sea claims of a coastal state or their recognized sovereign rights in the Exclusive Economic Zone (EEZ). At least 33 coastal states have the right under Article 76 (Continental Shelf regime) to claim seabed jurisdiction beyond 200 nautical miles (EEZ limit). In addition, several states have "Pioneer Investor" status with regard to seabed resources in international waters (The Area). A global maritime boundary database (GMBD) has been developed as a basic resource identifying the current claims of coastal states. It provides detailed information on existing boundaries and limits determined by the UNCLOS accords or by multi-lateral agreements which affect mineral exploration and exploitation. This paper will describe the GMBD and its construction and maintenance.

Jan 1, 2000