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By Katherine H. Walton

The research affiliate projects of the Continental Shelf Division of the Marine Minerals Technology Center concentrate on the development of technologies and methodologies for the exploration 4 and assessment of nonfuel continental shelf mineral resources within the U.S. Exclusive Economic Zone. Three of the FY 1990-91 research grants are summarized below. Scientists at the Center for Applied Isotope Studies at the University of Georgia have developed ?An Advanced Design for a Seafloor Gamma Isotope Mapping System? for the rapid collection of data on seafloor sediments. This system is designed to detect gamma radiation emitted by naturally occurring radioactive elements found in marine sediments. This data can be used to study seafloor lithology and has direct application in marine mineral surveys. The purpose of this study has been to redesign and calibrate the system for marine mineral survey work. Recent modifications of the sled design, gamma radiation detector, and supporting software have resulted in considerable improvements in sensitivity, functional operation, and data acquisition.

Jan 1, 1991

By Robert G. Ditchburn

Dating seafloor mineralization at hydrothermal centres of submarine arc volcanoes is important for understanding deep-seated volcanic events that can produce deposits rich in base and precious metals. The activity ratios, 228Th/228Ra, 228Ra/226Ra (Bq.Bq-1) and 226Ra/Ba values (Bq.g-1) are used for dating barite- rich seafloor massive sulphide (SMS) in the age ranges 0.3 ? 12 years, 3 ? 35 years and 500 ? 15,000 years, respectively. Thus, the time elapsed to amass an economic deposit and, ultimately, its capacity for sustainable extraction, can be estimated. 226Ra/Ba and 228Ra/226Ra values have been measured in relatively young chimneys that were collected, 1998 to 2006, from hydrothermal sites at Brothers and Clark volcanoes (Kermadec arc) and East Diamante volcano (Mariana arc) to check these initial ratios, essential for calculating ages for older mineralization at the same sites, were not varying significantly. We found that the 226Ra/Ba value for fresh SMS mineralization at the Brothers NW caldera and East Diamante hydrothermal sites have been reasonably stable for 6 years and 2 years, respectively. At both sites, the 228Ra/226Ra value for fresh SMS has been stable for 5 years. This was established from young chimneys where the measured 228Ra/226Ra value could be corrected for radioactive decay using the age derived via the 228Th/228Ra method. However, long-term stability of the initial 226Ra/Ba and 228Ra/226Ra values has yet to be proven. These isotopes of Ra are used as a proxy for better understanding of the transfer of Ba from deep magmas to the seafloor, via the circulating fluids of the hydrothermal system.

Jan 1, 2011

By Kaihui Yang

Volcanogenic massive sulfide deposits are generally considered to have been formed by hydrothermal fluids that leach ore metals out of footwall rocks. However, the necessity for a metal-rich magmatic component in the ore-forming fluid of "giant" ore deposits has been debated over the decades. The solution to this issue is important not only for metallogenic models but also for the mineral exploration. In the hydrothermal leaching model, massive sulfides at mid-ocean ridges are deposited from hydrothermal fluids containing 80 ppm Fe, 6 ppm Zn, 2 ppm Cu, 350oC, and 0.7 g/cm3 density (average data for 21oN East Pacific Rise). A simple calculation demonstrates that such a dilute fluid is unlikely to have been responsible for the formation of the largest ancient massive sulfide ores of greater than 100x106 tonnes, such as Kidd Creek, Brunswick No. 12, Neves Corvo, and Rio Tinto. For such a deposit consisting primarily of pyrite, sphalerite, galena and chalcopyrite (other minerals, including gangue, might account for an additional 10-20%) and even assuming 100% precipitation and retention of the sulfides, more than 790 km3 of vent fluid would be required. For typical water-rock reaction ratios of about 2, this fluid would have to have reacted with about 395 km3 of rock to acquire its metals by conventional leaching processes. This estimate, however, conflicts with the observation that even a giant massive sulfide ore body is usually underlain only by a few cube kilometers of obviously altered rocks. Moreover, this model is not consistent with the observation of hanging wall alteration in many large massive sulfide deposits. The close spatial association between massive sulfides and volcanic rocks, in both ancient and modern sea floors, suggests that direct magmatic contribution should be taken into account in the genetic model. Magmatic fluids, capable of carrying abundant ore metals and volatiles and escaping from magma by depressurization, are well known from modern active volcanoes on land. High concentrations of metals occur in CO2-rich magmatic fluid trapped in felsic volcanic rocks nearby large presently-forming VMS deposits in the eastern Manus Basin (Pacmanus, Suzette) and also in the footwall rocks of Ordovician giant Brunswick #12 deposit in the Bathurst district, New Brunswick. Only 1% of such metal-rich magmatic fluid mixed with heated sea water, that has leached its metals from rocks, would contribute 85% of the total metals to form an orebody. Such magmatic fluids are most likely to be formed from volatile-rich felsic magmas that are prevalent in back arcs, and, if added to the normal circulation system, the fluids could be responsible for the formation of "giant" ore deposits. If this is true, then the study of magmatic fluids in the seafloor volcanic rocks may provide criteria for the exploration of large ore deposits.

Jan 1, 2011

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

By Øystein Sture, Kurt Aasly, Ben Snook, Sigurd A. Sørum

INTRODUCTION Efficient exploration methodologies for base metal deposits have huge benefits for future deep sea mining endeavours, and underwater hyperspectral imaging (UHI) has been variably demonstrated to have applications in the identification and characterisation of mineralisation on the seafloor for both nodules and seafloor massive sulphides (SMS) (Dumke et al., 2018 and 2017 respectively). Due to growing resource requirements (Singer, 2017), SMS deposits are considered to be increasingly significant sources of copper and zinc, as well as silver and gold. This style of mineralisation is currently occurring at active hydrothermal vents (black and white smokers) but now-inactive sites also have the potential to be large mineral deposits. As such, the development of novel methodologies to detect both on-going and extinct mineralisations are of high importance. Geological setting During the MarMine cruise (Ludvigsen et al., 2016), non-mineralised host rock, low grade ore and high grade ore grab samples (Snook et al., 2018) was collected by ROV from the Loki’s Castle deposit (Pedersen et al., 2010), located on the Mohn’s/Knipovich junction on the ultra-slow spreading Arctic Mid-Ocean Ridge (AMOR), at a depth of approximately 2300 m. This material has been characterised as part of the MarMine project (e.g. Snook et al., 2017), and, by imaging compositionally constrained material, the measured hyperspectral responses can be used to generate a library for identification of deposits on the ocean floor. UHI technology Remote sensing with hyperspectral and multispectral technologies has seen wide use in prospecting for ores and hydrocarbons on land (Van der Meer et al., 2012). Iron oxides and sulphides have low blue reflectance and high red reflectance in the visible spectrum. The ratio between these two pairs has been used in exploration for terrestrial deposits of hydrothermal origin (Sabins, 1999). This discrimination typically also includes wavelengths exceeding the visible spectrum (1.5µm – 2.5µm). These wavelengths are typically not utilised underwater because infrared wavelengths and higher are rapidly attenuated in water. However, discrimination based on the full shape of the spectral response in the visible light (350nm – 800nm) may still be possible (Bolin and Moon, 2003). Resolving the endmembers from the spectral responses requires prior knowledge about the optical properties of the materials, i.e. their reflectance. These reflectances can be obtained in a controlled environment, where the spectra of the lamps, wavelength- dependent attenuation in water and scattering of light can be accounted for (Johnsen, 2013).

Jan 1, 2018

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 Hunsoo Choi, Sung Rock Lee, Ian J. Graham, Ian C. Wright

This is a part of the joint KIGAM-GNS-NIWA 3-year study of ferromanganese modules in the Campbell Nodule Field, east of Campbell Plateau to determine age distribution, growth rates and geochemical evolution in relation to geographic setting. The petrography, chemistry, inferred genesis, and 10Be/9Be dating of the nodules were described in the science report of GNS (Chang et al., 2003a, 2003b; Graham et al., 2003a) and presented at UMI (Chang et al., 2003c; Graham et al., 2003b). The morphology and distribution of ferromanganese nodules were also published in detail (Wright et al., 2005). This presentation is only concentrated on the mineralogy and chemistry of the nodules.

Aug 24, 2006

By Grigori Abramov

As we enter into the 21st Century, miners are looking more attentively at new mining technologies allowing decrease environment damage along with operational cost. This technic would allow developing of poor and difficult mineral deposits, including the World Ocean offshore zone. Borehole Mining is an underground/underwater remote method of mining carried out from floating platforms or vessels. Definition of Borehole Mining (BHM), working schematic, main technical data and its advantages are given. The method is currently in use in mining of different type of raw materials, such as: uranium, iron ore, quartz sand, coal, polymetallic ores, phosphate, gold, diamonds, rare earths, amber and more. It is also in use in oil and gas stimulation, salt domes storages building and environmental problems solution. Recently recorded data of Borehole Mining productivity (80-100 t/hour/hole) and a depth of mining (over 1 km) has been achieved in a last couple years. Remoteness of method not only secures complete safety of operations but also allows wide sector of underwater applications. The World leaders in Borehole Mining are Russia and the United States. Based on previous experience the Universal Tool for Seabed Borehole Mining has been developed for wide sector of usage: from exploration and mining - through oil & gas stimulation to souterrain storages construction and lake's bottom cleaning.

Jan 1, 2000

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 Tetsuo Yamazaki

Natural methane hydrate has been scientifically studied as a global carbon reservoir. However, in Japan, it?s potential as an energy resource has been industrially highlighted, because there are few domestic oil and natural gas resources in Japan, but many potential deposition areas for methane hydrate in the sea around Japan. Less CO2 discharge from methane compared with coal, oil and conventional natural gas for the same calorie value is considered an advantage for its use as an energy resource. Because methane hydrate is distributed at shallow depth in sediments on the ocean floor, accidental leakage of methane may occur while we utilize methane hydrate. Methane itself has a considerable impact on the greenhouse effect, if it reaches the atmosphere. Therefore, it is necessary to estimate its behavior in the environment after leakage if we want to use methane hydrate as energy resource. The mass balance after leakage of methane on the seafloor and in the water column can be studied through the analyses of natural cold seepages and hydrothermal activity.

Jan 1, 2004

By Anthony T. Jones

Deep seabed mining requires technology to collect materials and transport them to the surface. An international patent search was conducted to define the state of the art in seabed mining technology. Over 350 patents were identified from 12 patent systems. The majority was from the United States, Japan, and the former USSR. Patent activity in this field peaked in 1983 when 34 patents were issued. Since 1984, on average 6 patents have been issued annually. The technology represents ten major classifications. With the exception of Deepsea Ventures, Kawasaki and International Nickel, it appears that much of the technology developed and tested in the 1970s by consortia active in seabed mining was never patented. Over the past two decades, identifiable trends in marine technology could influence seabed mining application such as more sophisticated communication systems, advances in hydraulic manipulators, improved computational technology in navigation, modeling of vessel ? ocean interactions, and improved materials. The most significant recent activity has been in European applications, which disclose remotely controlled subsea vehicles for mining diamonds.

Jan 1, 2001

By Nobuyuki Okamoto

The present three-year long phase of the SOPAC/Japan Deep Sea Co-operative Mineral Resources Programme [Programme], commenced in 2000. The Programme has been funded by the Government of Japan through the Japan International Co-operation Agency (JICA) and the Metal Mining Agency of Japan (MMAJ), since 1985. Field survey activities and associated data analysis and interpretation, for the Programme, has largely been carried out by the Deep Ocean Resources Development Co., Ltd. (DORD). The Government of Japan has, since 1982, recognised DORD as one of its ? Pioneer Investigators? for manganese nodules in the Clarion Clipperton Fracture Zone . Although the objective of this paper is to present the results of the drilling cruise that was conducted from December 2001 to January 2002, within the North Fiji Basin, in Fiji?s EEZ, it will also seek to provide a broad overview of the results of the cruise conducted within the Cook Islands in May to June 2000, as well as present preliminary results of the cruise conducted in the Marshall Islands in June to July 2002.

Jan 1, 2002

By Michael J. Cruickshank

The University of Hawaii, Ocean Basins Division (OBD) shares, equally with the University of Mississippi, Continental Shelf Division (CSD), congressional funding for the Marine Minerals Technology Center, a Generic Minerals Center under the U.S. Department of the Interior's Mineral Institutes Program. The State of Hawaii supports the program by the provision of salaries for the Executive and Technical Directors and by the provision of fiscal, administrative, and facilities support through the Hawaii Natural Energy Institute, the Research Corporation of the University of Hawaii, and the School of Ocean and Earth Science and Technology. The Center's program of research, technology development and education is multi-disciplinary and international in scope. Activities since the MMTC/OBD was established in June 1988 have included: Research projects * Development of a Free-Fall Seafloor Hard Substrate Corer. * The Microtopography of Manganese Crust deposits. * Evaluation of the Cobalt Crust Continuum on Seamounts in the Hawaiian Exclusive Economic Zone. * Graphite Furnace Atomic Absorption Spectrometer. * Computer Aided Design Methodology for Power, Communication and Strength Umbilicals. * Characterization and Environmental Impact Assessment of Tropical * Reef-derived sands for Beach Replenishment.

Jan 1, 1991

By Dorothy B. Niell, O&apos

In its first three years of operations, the in-house programs of the continental Shelf Division of the Marine Minerals Technology Center (MMTC/CSD) have focused on the development of drill systems - technology and the improvement of techniques and applications of reconnaissance methods to marine mineral deposit characterization. Many of the technological advances made to date have been in direct response to specific requests from industry for drill systems needs, and from federal and state agencies seeking technical support for various research efforts. These cooperative programs have proven to be an extremely efficient and effective way for the MMTC to achieve some of the main program goals that were established for the organization at the outset: primarily, to encourage and assist U.S. industry in marine minerals research activities and to encourage cooperative work among research institutions, government agencies, and industry. The primary achievements of the MMTC/CSD to date include the development of the Remote Placer Drill System for rapid reconnaissance drilling of precious metal placer deposits (including both pneumatic prototype and hydraulic production

Jan 1, 1991

By Dallas L. Peck

The U.S. Geological Survey (USGS) recently completed phase 1 of a mapping effort that makes the United States the first nation to systematically acquire image maps of its underwater lands. In 1984, the USGS, as part of its mission to map and characterize the resources of the Federal lands, began a mapping effort in the newly proclaimed Exclusive Economic Zone (EEZ). The goal was to provide sonar image maps of this frontier area within 10 years. The mapping program is on schedule, with two-thirds of the EEZ sea floor, approximately 2 million square nautical miles, happed in 7 years. The deep water EEZ (depth greater than 200 m) around the 50 states is now complete except for the North Slope of Alaska, where ice precludes our surveying with a surface ship. Phase 2 of the EEZ mapping effort will begin in 1994, focusing on the American Flag islands of the western Pacific. Approximately 1 million square nautical miles of sea floor remain to be mapped around the islands.

Jan 1, 1992

By Carsten Rühlemann

Between 2008 and 2013, the German Federal Institute for Geosciences and Natural Resources (BGR) carried out five exploration cruises to the German license area in the eastern Pacific Nodule Belt. The first two expeditions were mainly dedicated to multibeam mapping to obtain an overview of the seafloor topography and acoustic backscatter strength. These data were used to identify ten to fourteen prospective nodule fields for potential future mining, which together cover about 16% of the total license area of 75,000 km2. During the last three cruises, three of these potential mining areas were explored in detail. For this purpose, the BGR developed a suite of exploration methods to map nodule size distributions and nodule abundances. These methods include acoustic surveys with vessel-based multibeam systems as well as near-bottom video mapping complemented by in situ sampling. The economically most valuable field has a size of ca. 2,000 km2, of which 34% is covered by medium to large nodules (> 4 cm long axis of nodules) with an average abundance of 22.4 kg/m2 and 44% is covered by small nodules (< 4 cm) with a mean abundance of 17.5 kg/m2. The total mass of nodules in this field comprises more than 30 million tons wet weight and could sustain deep-sea mining for at least 10 years.

Sep 14, 2011

By Chan Min Yoo, Kiseong Hyeong, Inah Seo

INTRODUCTION One of the major concerns for deep seabed mining is its environmental impact, from the disturbance of benthic communities due to the mining activity to the disposal of mine tailings back to the ocean. Yet a significant amount of waste materials would be produced from the on-deck processing on the mining platform, all the materials that produced on the mining platform are to be shipped to the land unless the related regulation and guidelines are developed by IMO and ISA (ISA, 2018). Still, ecotoxicology data for the deep seabed minerals from case studies in deep-sea tailings disposal (DSTD) and submarine tailings disposal (STD) sites are lacking and all other related aspects are also largely unknown. This year, the Republic of Korea has started a research project for the more comprehensive understanding of chemical and physical properties of mine tailings from the on-deck processing and the possible environmental impacts on the marine organisms after its disposal. Based on the scientific data collected from this project, Korea would be able to make recommendations for the methods and technical standards for the deep seabed mining discharges. The subjects of this project are threefold: to understand the physical/chemical properties of the tailings, to model the dispersion of particulates after the disposal, and to assess its impact on the marine ecology. Laboratory Experiments Producing Mine Tailings First, the possible waste materials are produced by mimicking the collecting and dressing processes at sea. The polymetallic nodules (PN) would be mined by using a collector lifting the crushed nodules out of the bottom sediment, and the bottom water, accompanying sediment, and the fine nodule particles which are too small to be recovered would be discharged to the ocean and thus are considered as tailings (Schriever and Thiel, 2013). In the laboratory, PN is crushed into the fragments smaller than 2 cm, abraded in the water using the rock mill, and then sieved to obtain the fine particles to be disposed.

Jan 1, 2018

By Charles L. Morgan

For the past twenty years or so the oceans of the world have been transformed in the minds of most Americans from the ultimate and nearly infinite receptacles for sewage and other wastes to an almost sacrosanct and threatened last refuge of Mother Nature from man on Earth. While this general movement has helped somewhat to moderate the flows of pollutants into the oceans, it has had severe and sometimes devastating impacts upon various attempts to develop seabed mineral resources. Marine mining proposals have been easy targets for attack. In most cases, they have short or no histories and involve prototype or first-generation methods. They commonly lack major financial backing, and do not command significant public support. Their constituents are limited. Opposition movements to such proposals have been able to evoke strong support by appealing to this "last refuge" image and depicting mining operations as the final assault. In mounting these public appeals, the movements obtain visibility and support. Because of the small and sometimes tentative status of the constituencies which support particular proposal s, the potential liabilities for opposition movements are minimal.

Jan 1, 1989

By J. Robert Moore

Introductory remarks will be made by the speaker, chiefly on recent and current developments in the industrial, agency and academic sectors that relate to the status of marine mining and mineral exploration programs and to recommendations for strengthening and continuing these programs. Subsequent to these brief comments, a selected panel with representation from industry, academe and government will address the following related topics: 1) development and objectives of new centers for marine mining technology, 2) cooperative R. and D. programs between academe and the user groups, 3) arrangements for specialized training and student instruction that will provide for educational components, and 4) funding and other support for implementing new centers and new programs. The panel discussion will be open to all UMI participants and whose contributions will be both solicited and encouraged.

Jan 1, 1986

By Alexander Malahoff

The study of why and how life survives in the Extreme environment is a major frontier of science today. Extremophiles are organisms that require extreme environment including high temperature, pH, pressure and salt concentration, or low temperature, pH, nutrient concentration, or water availability. Their common habitats are geothermal vents, pools, lakes and craters of active volcanic regions, such as those of New Zealand, Japan, Kamchatka, Yellowstone USA or the hydrothermal vents of the ocean ridges and submarine volcanoes. These settings are accessible by foot, boat, helicopter, or submersibles. This presentation examines the geology, chemistry of geothermal sites of New Zealand, including the active volcano, White Island, Yellowstone, the submarine volcano Loihi in Hawaii, and sections of the mid-ocean ridges. Designing process and construction of Extremophilic sampling and bioreactor systems used in the study of Extremophiles will be discussed. The driving force behind the research of extremophiles is not only the fundamental science, but also biotechnological potential associated with these microorganisms and their cellular products. The University of Hawaii?s Marine Bioproducts and Engineering Center (MarBEC) is laying the foundations for such new industries.

Jan 1, 2001