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By Derek Ellis

There are two environmental issues which have only recently begun to need planning in detail for marine mining. One is the environmental consequences of mine closure; the other is environmental terrorism. In principle it is not difficult to predict the pattern and rate of biodiversity recovery after mine closure on metalliferous depositional seabeds. 1-5 years to a self-sustaining community of organisms is a generalized guideline, depending on depth and particulate composition. The rate and pattern of biodiversity recovery on some metalliferous hard-rock habitats is far less predictable due to the patchiness and rareness of the habitat. Ecoterrorism at mines, whether on-land or marine, is now to be expected. A good example of resource industry ecoterrorism is the fire-bombing of logging and cement trucks in Oregon in 2001. But there have also been bombs at mine sites, as at Asbestos, Quebec. It is also possible to regard some resource-loss lawsuits as frivolous, hence forms of ecoharassment. Marine mining operations should take note of the development of environmental terrorism (and terrorism in general) and its various manifestations and impacts. Potentially these range from minor work stoppage inconveniences, to serious financial risk jeopardizing the economics of a mine, to jail for company executives, managers and environmental staff, and to harassment and killing of mine personnel.

Jan 1, 2005

By Steven D. Scott

Stephen D. Scott Steven Scott is a Professor of Geology, Director of the Marine Geology Research Laboratory and, until May 1997, was Chairman for 9 years of Geological and Mining Engineering, all at the University of Toronto. Steve also holds a cross appointment at the University of Western Brittany's European University Institute of the Sea in Brest, France. He was educated at the University of Western Ontario (B.Sc. and M.Sc.) and at Penn State (Ph.D.). Steve is a geologist/oceanographer specializing in base and precious metal massive sulfide deposits which he and his students have studied on five continents and on the bottom of three oceans. He was the first ore deposits geologist and first Canadian to witness "black smokers" on the ocean floor. Since 1982, he has participated on 21 oceanographic surface and submersible expeditions, many of them as Chief Scientist. His research team is currently carrying out projects in the W and NE Pacific Ocean. Steve has published more than 150 research papers and lectured in more than a dozen counties. Popularized accounts of his work have appeared in various media.. He has been honored by several awards and distinguished lectureships. Steve is President of the Canadian Scientific Submersible Facility, which operates the Canadian ROPOS robotic submersible, and is President of the International Marine Minerals Society.

Jan 1, 1998

By Jerry Hanua Naime

Papua New Guinea has permitted its first underwater mine. Nautilus Minerals (PNG) Limited is the company permitted to operate the Solwara 1 project. The project is located 30km off the nearest island of New Ireland in the Bismarck Sea. The successful permitting of the activity was due to the existence of a broad legislative framework and the collaborative efforts of stakeholders. Challenges faced included the lack of specific guidelines or policies for underwater mining; lack of existing technology and/or mining method; lack of benefit sharing mechanism for such a project and management of the perceptions of local communities that fear environmental degradation by the mining project. This presentation shares the experience of Papua New Guinea?s first under water mine. A background of the country, the project and the legislative framework are presented. Followed by the challenges and approach taken to permit the project.

Jan 1, 2010

By Derek V. Ellis

A stepwise implementation of seven criteria for screening the physical, chemical and environmental suitability of submarine tailing disposal (STD) at coastal mines is presented. It is expected that similar criteria would be relevant to future deepwater mining. A reconnaissance level study of four preliminary criteria: mine location; coastal bathymetry; feasible outfall locations; and potential for chemical contamination can support or eliminate the prospects for STD. If supportive, detailed, and far more time-consuming hence costly surveys of: environmental background information including oceanography and waste discharge characteristics; projected impacts on other resource uses plus regulatory and community concerns will be essential for environmental protection and to secure the necessary approvals. This review of STD systems on which the proposed screening criteria were based was undertaken by a Cooperative Agreement of the U.S. Bureau of Mines, Alaska Field Operations Center with the University of British Columbia.

Jan 1, 1994

By Curtis Clement

Williamson & Associates, Inc. has developed a marine mineral exploration tool using an induced polarization technology (IP) under license from the US Geological Survey. Developed by Jeff Wynn at the USGS, this method has gone through several prototyping stages and is now in commercial use to map offshore ilmenite deposits. Preliminary results of a recent resource mapping program are discussed as well as potential applications in the detection and quantification of other minerals in marine sediments.

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 C. L. Mardock

The U. S. Bureau of Mines participated in a two-year joint State of Oregon/Department of Interior Placer Task Force study on the economic and environmental aspects of Oregon's marine placer deposits. The effort culminated in a research cruise off the southwest coast of Oregon to investigate the geological and biological characteristics of the continental shelf deposits. The Bureau's role was to collect and study the placer material off the continental shelf and to determine its strategic potential and significance. In-depth characterization of the sediments by optical and electron microscopy verify that the placer material from Cape Blanco contains up to 3 pct ilmenite, 0.5 pct chromite, and small amounts of zircon and gold. However, harsh sea conditions and equipment failures prevented sampling below a four-foot depth at the Cape Blanco site. Results to date indicate that the deposits sampled off the southwest coast of Oregon do not represent a significant source of strategic minerals. However, further study of the deeper sediments off Cape Blanco may uncover significant concentrations of chromite. This presentation encompasses the site geology, the geophysical and biological activities of the expedition, and the results of the Bureau's mineralogical and chemical investigation. The combined findings of the Bureau and other Task Force agencies have provided information needed to expand the country's limited knowledge of marine mineral resources and has assisted state and federal agencies in the formulation of offshore mineral policies.

Jan 1, 1991

By Seung-Kyu Son

Environmental properties of the northeast Equatorial Pacific along 131.5 degrees west, between 5 degrees and 13 degrees north latitude, were investigated in association with changes in water column structures during the summer seasons of 1998 and 1999. Climatic disturbances such as El Nino and La Nina, should have affected this area during the study period. In 1998, a thermocline where temperatures rapidly decrease with depth, was formed at 90~110 m water depth. However, in 1999, a very fluctuating thermocline was observed with latitudes. As a result of changes in the water column structures, biological and chemical environment also showed fluctuation parallel to the changes in other physical parameters. Inorganic nutrient depleting areas, especially for nitrate+nitrite and phosphate, or oligotrophic regions were extended down to approximately 100 m depth, which coincided with the surface mixed layer depth. In the euphotic zone, depth integrated nitrogen (N) and phosphorus (P) values were 34 g-N/m2 (grams of Nitrogen per square meter of sea floor), 7 g-P/m2 in 1998 and 130 g-N/m2, 18 g-P/m2 in 1999, respectively. The results indicated that nitrogen (96 g-N/m2) and phosphorus (11 g-P/m2) are supported by up-welling and down-welling phenomena with convergence and divergence in the study area. Biological parameters in the water columns were largely determined by the physico-chemical environmental parameters. Subsurface chlorophyll maximum layers were coincided with the formation of seasonal thermocline. Copepods were the dominant group of zooplankton community at three sampling stations (N5, N6, N10) terms of abundance, which was the same results of previous surveys for the past 3 years. Among copepod populations, Oncaea sp., Oithona sp. Clausocalanus sp., Acarocalanus sp. and juvenile copepodites were dominant Appendicularians, foraminiferans and radiolarians were also dominant. To investigate diel vertical migration pattern of zooplankton, repeated samplings from the water depth of 0~50m and 50~200m were conducted at KODOS (Korea Deep Ocean Study) area before and after sunrise. Zooplankton abundance was slightly higher after sunrise than before sunrise in the surface layer. Chlorophyll-a concentrations were relatively low as the concentration of sediment increased in most experiments possibly due to a decrease of grazing pressure of microzooplantkon such as ciliates, which is the efficient grazer on small-sized phytoplankton. Because copepod predation on microzooplankton may be prevented by the high concentration of sediment, resulting in lower grazing pressure on small-sized phytoplankton. The results obtained during the baseline study as a part of KODOS project since 1998.

Jan 1, 2001

By Steven D. Scott

Several polymetallic sulfide deposits (copper, zinc, f lead, silver, f gold) presently exposed at the surface of the ocean floor are of sufficient size and apparent grade that they will someday be seriously considered as mineable resources. Responsible ocean mining may have some real environmental advantages over land mining, although they both share the same downstream problems caused by smelting and refining. The area of disturbance for an ocean mine would be much less than for an equivalent sized deposit on land around which considerable rock has to be excavated in order to get at the ore. Acid mine drainage, a very serious problem in land ming, would not be a concern in the alkaline and oxygen deficient environment of the deep ocean. There would undoubtedly be loss of habitat for some marine organisms but this could be minimized by mining deposits that are no longer hydrothermally active and therefore support little life. The risk of severe corrosion and thermal damage to the mining equipment at hydrothermally active sites would probably preclude their recovery in any event. The scientific community and environmental advocates should take advantage of the long lead time before ocean mining commences to insure that the environmental mistakes of the past, as encountered in some land mining, are not repeated. In order to fully understand and thereby mitigate the consequences of recovering seafloor sulfides, test mining of a small deposit using the German-designed high capacity television grab, preceded and followed by detailed observations of the mining site from a submersible, is proposed.

Jan 1, 1992

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 Brenda J. Burd

A very extensive spatial and temporal database on benthic infauna and associated sediment metals has been collected for Island Copper Mine on Vancouver Island, B.C. Canada from 1969 (pre-discharge) to 1998 (3 years post-discharge). The tailings deposited as organically impoverished, copper-rich, clays, silts and sands distributed according to particle size, bottom turbidity currents and strong, vertically mixed tidal currents. In addition, a large deposition of coarser waste rock along the north shore of Rupert Inlet contributed substantial material in the shallower, near-field area.

Jan 1, 2001

By Robert R. Tarver

A long history of gold production at Nome, Alaska has resulted in long term interest in the nearshore environment as a production target. Mining by Western Gold Exploration and Mining Company offshore of Nome yielded approximately 100,000 troy ounces of gold in the period 1986 through 1990. This study was designed to determine the relationship between heavy minerals, sediments, and gold concentrations which occur in the upper meter of sediment offshore of Nome. Standard procedures were implemented for grain size analysis, heavy mineral separations, and heavy mineral frequency determination.

Jan 1, 1991

By James R. Hein

A new data set of cobalt-rich ferromanganese (Fe-Mn) crust chemistry has been completed for the first detailed sampling of a latitudinal crossing of the Pacific equatorial zone of high biological productivity. Samples were collected in January-March, 1999, during the AVON 2 cruise aboard the R.V. Melville, Scripps Institute of Oceanography. Samples were collected from 4.6° N to 9.2° S latitudes along two ridges, the Marshall Islands-Gilbert Islands ridge (4.6° N to 3.5° S) and the Howland Island-Tokelau Islands ridge (1° N to 9.2° S). The two ridges are offset east-west in the region of overlapping latitudinal sampling by about 466 km. We determined the concentrations of 48 elements for 147 samples from 39 dredge hauls taken on 33 seamounts and island flanks that occur between the Marshall Islands to the northwest and Samoa to the southeast. Element concentrations can be examined as varying spatially and with water depth in the ocean and we examine those relationships based on statistical analysis of the chemical and spatial data. The mean Fe/Mn ratio of 1 and mean Co content of 4645 ppm are typical of West Pacific hydrogenetic crusts; but the mean Co content is low compared to those of some equatorial North Pacific sites, such as the Marshall Islands and Johnston Island EEZs. In contrast, the mean Cu concentration (1540 ppm) is 35% higher than the mean concentration for Pacific Ocean Fe-Mn crusts (998 ppm). Another striking difference is the 40% higher Ba concentrations (mean 3107 ppm) compared to typical Central and West Pacific crusts (mean 1876 ppm); but Ba concentrations are lower than those in California continental-margin Fe-Mn crusts (mean 4085 ppm). A final significant difference in Fe-Mn crust chemistry is Zr concentrations, mean 921 ppm (maximum 1523 ppm), which is about 30% higher in this data set compared to the previously determined mean value of 613 ppm for Central and West Pacific crusts. Zirconium has a strong positive correlation with Ba and a weak positive correlation with Mn.

Jan 1, 2003

By Andrea Koschinsky, Luise Heinrich

(for an oral presentation) Activities for preparing future deep-sea mining offer the unique opportunity to study environmental conditions and anticipate adverse environmental impacts prior to the commercialization of the activity. Until know, environmental research has first and foremost focused on understanding direct impacts occurring at the seafloor or in the water column such as the removal of substrate, the suspension of sediment or the creation of particle plumes. Impacts occurring above the sea surface have thus far rarely been considered. The operation of deep-sea mining equipment, as well as of mining and transport vessels will be associated with a considerable energy demand. In the open ocean, this energy will be provided by heavy fuel oil (HFO), which is the cheapest and most common marine fuel. The combustion of HFO will be associated with the release of greenhouse gases and other pollutants. Deep-sea mining will thus directly add to already critical air pollution levels caused by international shipping. To contribute to a holistic assessment of deep-sea mining impacts and to address the previously outlined knowledge gap, we present the methodology to quantify the fuel consumption and associated emissions of a potential typical commercial manganese nodule mining operation in the Clarion-Clipperton Zone (Fig.1). Using the mine set up and energy demand estimates from a study commissioned by the German Federal Ministry of Economic Affairs and Energy supplemented by information from literature, we anticipate emissions of carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), nitrous oxide (NO2), nitrogen oxides (NOx), sulfur oxides (SOx), particulate matter and non-methane volatile organic compounds.

Jan 1, 2018

By Du Gon Lee

This study presents a model to predict fate of resuspended sediment in the development of deep-sea mineral resources including manganese nodules under Clarion-Clipperton area of the Pacific Ocean. The manganese nodules are expected to be developed near future and major research is undergoing in Korea recently concerning many aspects of the mineral resources development. One aspect is about environmental concern related to the deep-sea development, and a major environmental problem is the resuspended deep-sea sediment. In order to quantitatively analyze the resuspended sediment in the water column during the deep-sea development, particle size distribution (PSD) was considered an important factor in this research. The model developed here includes PSD and coagulation process, as well as sedimentation process. The model is one dimensional in the vertical profile, and was designed to describe the change of particle size distribution in the water column in the given vertical point. Based on the mathematical modeling, a numerical model was developed. Using the model, basic simulation was performed under representative environmental setting of the deep-sea environment. The simulation showed the dynamics of change of particle size distribution for 50 m depth of water column from the deep-sea bed, up to 10 days of simulation time. The simulation results indicate that coagulation seemed an important factor in the fate of resuspended deep-sea sediment. As a result, this research shows that the particle size distribution approach, as well as considering the coagulation process, is needed and may be effectively applied to environmental impact analysis of deep-sea resuspended sediment. Key Word: Deep-sea Mineral Resources, Resuspended Sediment, Environmental Impact, Particle Size Distribution, Coagulation, Modeling and Simulation

Jan 1, 2003

By James R. Herring

An unusual combination of ten new, deep (-100 m) coreholes and an extensive high-resolution seismic reflection network enables us to produce a detailed study of the phosphorite resources in the Tertiary strata of the Georgia continental shelf. These strata are mixtures of a terrigenous facies, notably quartz and clay along with minor amounts of other aluminosilicate minerals, and of a marine facies, notably phosphorite and carbonate. Phosphatic sediments occur throughout the cores, however the richest phosphorite beds are in the middle Miocene (Serravallian) sediment, where they constitute up to 70 percent of the sediment mass. Major zones of phosphate enrichment occur chiefly at major unconformity boundaries (tops of Oligocene, lower and middle Miocene, upper Miocene, and lower and upper Pliocene) and at prominent intrastratal reflectors representing minor unconformities within units. Phosphorite co-occurs with the clay minerals, especially palygorskite, but correlates inversely with carbonate and detrital quartz, indicating a low-energy depositional environment. The clay minerals present in these strata, which have an environmental consequence on recovery of the phosphorite, are varying concentrations of smectite, kaolinite, mica, palygorskite, and sepiolite. Phosphatic resources have been determined within only the Miocene strata. Sediment volume for this unit to the 100 m isobath on the continental shelf has been established using the high-resolution seismic reflection network that has been calibrated using the deep coreholes. Phosphorite grains larger than 0.1 mm average about 40% of the sediment. In turn, most of the remainder of the sediment in this size range is quartz, which is separable from phosphate grains using conventional flotation techniques. Our estimate is that 300 Gt of phosphorite lie within the Miocene strata of the Georgia continental shelf.

Jan 1, 1994

By Masaru Nakamizu, Tetsuya Fujii, Tatsuo Saeki, Ken-ichi Yokoi

Methane hydrate, a solid compound formed from methane and water, occurs naturally in permafrost regions on-land and in deep continental slopes offshore and has been examined as future energy resources. The existence of methane hydrate in the eastern Nankai Trough region, offshore Japan, was confirmed by drilling the MITI well “Nankai Trough” in 1999. Aiming commercialization of methane hydrate production, the Research Consortium for Methane Hydrate Resources in Japan (MH21, core associations: JOGMEC[*1], AIST[*2] and ENNA[*3]) under METI [*4] has been executing geological and geophysical surveys around the eastern Nankai Trough since 2001 as a nation project.

By Robert M. Owen

The reconstruction of ocean history has been a major focus of marine research over the past decade. A significant outcome of these investigations is the recognition that certain types of marine mineral deposits are linked to regional to global scale changes in ocean composition and climate conditions. Manganese-bearing deposits are of particular interest in this regard because changes in their occurrence, distribution and/or composition are responsive to both biochemical and geological factors. Analyses of such deposits whose formation spans critical age/epoch boundaries thus provide clues concerning the interplay of different process during anomalous periods in Earth history. Recent studies demonstrating this deposit - event - process relationship include: (1) Changes in the bulk chemical composition of ferromanganese crusts during the Late Miocene-Early-Pliocene (-7-3 Ma) that coincide with a period of enhanced biological productivity in the eastern equatorial Pacific upwelling zone; (2) The formation of large statiform manganese deposits at the Cenornanian- Turonian Boundary (-92 Ma) in association with widespread oceanic anoxia; and (3) Increased deposition of hydrothermal precipitates caused by tectonic reorganizations at the Paleocene - Eocene boundary (-55 Ma) that resulted in global-scale changes in atmospheric and oceanic circulation and climate.

Jan 1, 1995

By B. S. Ingole, S. Jai Sankar, A. B. Valsangkar, R. Sharma, B. Nagender Nath, N. H. Khadge, P. A. Loka Bharathi

After the simulated ‘mining’ experiment (INDEX) in the Central Indian Ocean (in 1997); the restoration of benthic environment was monitored for 4 years (2001-2005) at 5 locations in and around the test site and at 3 reference stations (20-80 km) from the test site. A comparison of long-term monitoring data with the pre-mining and post mining observations has shown that: • The concentration of silt fraction which was the highest (50-60%) at most locations during ‘pre-mining’ and ‘post-mining’ phases, had reduced (40-50%) during monitoring phases. • There was a corresponding increase in clay concentration (50-60%) during the monitoring phase, implying change in the size of sediment particles settling on the seabed, a trend that was also observed at the reference locations. • The initial increase in water content and decrease in shear strength after the experiment, which appeared to be returning to normal in monitoring-1 (2001), was reversed during subsequent monitoring phases (2002-2005), indicating changes in benthic environmental conditions. • Sediment organic matter and pore-water chemical data have not only indicated partial restoration of geochemical properties after the experiment, but also cyclic changes during the monitoring period.

Oct 15, 2007

By Michael J. Cruickshank

Marine minerals are more than an academic curiosity as they represent the most significant global source of mineral materials for economically and ecologically sustainable development for the future. Minerals research is traditionally carried out by industry and thus, in the United States at least, applied research in marine minerals may not get the share of government funding or attention that more exotic programs for space exploration or future global disasters engender. Two recent events have significantly changed the status of marine minerals. Discoveries made in the last thirty five years indicate that the potential for mineral occurrences in the oceans and seabeds, area for area, is as high as for terrestrial lands. On this basis the global mineral resource base has been recently increased by a factor of four of which three quarters is underwater. The recently enacted Law of the Sea has mandated what is probably the most far reaching re-distribution of natural resources in human history, and has resulted in a peaceful subdivision of seabed jurisdictions between the coastal nations of the world which should significantly affect future mineral markets and the balance of economic powers. Significant applied research efforts are ongoing for marine minerals as an adjunct to commercial production in southern Africa for diamonds; and in many other parts of the world for sands for beach and coastal protection. Forward planing, including research and development activities focussed on future commercial production of metalliferous oxides, continues in Korea, China, Japan, India, and with lesser activity, in the United States, United Kingdom, Germany and the CIS. Annual expenditures for this work amount to millions of dollars. In all cases the environmental aspects of commercial produc¬tion are a significant part of the research. Geologic studies on the occurence and distribution of metal sulfides at plate boundaries continue on a regional basis in the Pacific.

Jan 1, 1996