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By William J. Scott

In the last two years, C-CORE has developed a new seabed sampler directed specifically at obtaining samples from hard or compacted bottoms such as are typical of marine placer deposits. Samples are required for appraisal of concentrations of saleable commodities, and for determination of levels of biological indicators in the deposits. Recently C-CORE and the University of Victoria have been comparing the performance of the Scott/C-CORE sampler with that of the Van Veen sampler often used for biological sampling. Initial trials of the Scott/C-CORE sampler in 1992 at the WestGold mining site, Nome, Alaska, were described by Jewitt et al. at the 1993 UMI. Since that time the sampler has been modified to prevent overfilling, and to limit turbulent flow of water across the top of the sampler buckets when the sampler is recovered with partly-open buckets. The modifications included shoes to prevent sampler overfill, and flexible rubber shielding over top and sides of the sampler to prevent water circulation. Samples have been taken with both samplers in two field areas, one at Pine Cove, Baie Verte, Newfoundland, and the other near Long Pond in Conception Bay on the Avalon Peninsula, Newfoundland. In each area multiple samples were taken with both sampler types, and the samples processed immediately to establish the types and quantities of marine organisms that were present. Species identification is expected to be complete by late August.

Jan 1, 1994

By Renee Grogan

"An environmental impact assessment (EIA) of a deep sea mining project typically describes the environmental baseline, impacts of the project to the environmental values, and proposed management techniques. Comprehensive EIAs also consider the impact of the mining project on existing industries, including deep sea fishing. However, few projects to date have included other industries in the EIA process in more than a cursory manner, due to the confidentiality of the process, conflicting priorities, and bureaucratic limitation. However, if the United Nations Sustainable Development Goals (particularly Goal 17: Collaboration) are to be achieved, a new way of thinking will be necessary for deep sea mining projects, starting with collaboration at the very beginning of the project life cycle.STRUCTURE OF PRESENTATIONThis presentation will be in the format of an oral (20 minute presentation).The presentation will cover the process of inter-industry collaboration throughout the life cycle of a deep sea mining project, drawing on historical and existing examples, including that of the Chatham Rock Phosphate Project in New Zealand."

Jan 1, 2017

By William J. Scott

In the last two years, C-CORE has developed a new seabed sampler directed specifically at obtaining samples from hard or compacted bottoms such as are typical of marine placer deposits. Samples are required for appraisal of concentrations of saleable commodities, and for determination of levels of biological indicators in the deposits. Recently C-CORE and the University of Victoria have been comparing the performance of the Scott/C-CORE sampler with that of the Van Veen sampler often used for biological sampling. Initial trials of the Scott/C-CORE sampler in 1992 at the WestGold mining site, Nome, Alaska, were described by Jewitt et al. at the 1993 UMI. Since that time the sampler has been modified to prevent overfilling, and to limit turbulent flow of water across the top of the sampler buckets when the sampler is recovered with partly-open buckets. The modifications included shoes to prevent sampler overfill, and flexible rubber shielding over top and sides of the sampler to prevent water circulation. Samples have been taken with both samplers in two field areas, one at Pine Cove, Baie Verte, Newfoundland, and the other near Long Pond in Conception Bay on the Avalon Peninsula, Newfoundland. In each area multiple samples were taken with both sampler types, and the samples processed immediately to establish the types and quantities of marine organisms that were present. Species identification is expected to be complete by late August.

Jan 1, 1994

By Nicholas Dyriw, Georgy Cherkashov, Tamara Stepanova, John Parianos, Anna Firstova

"Seafloor massive sulfide (SMS) deposits are a new frontier in global metal resources. Hydrothermal chimney’s (black smokers) precipitate Cu, Zn, Ag and Au rich from hot fluids (>250°C) during interaction with cold seawater ~2-4°C. Here we compare the sulfide mineralogy and geochemistry of Cu-sulfide chimney samples from two different tectonic locations: Solwara 1, a Cu-rich, transitional arc-back arc (Arc-BA) type SMS ore deposit and; Ashadze-1, a Cu-rich, ocean ridge type SMS deposit (Hannington et al., 2011).This work represents the first stage of a project aimed at investigating and understanding the significance of high Cu concentrations in SMS systems. Comparing these particular systems is significant because they share critical similarities despite being located at different seafloor depths, hosted in different rocks and are located in two different endmember tectonic environments. Critical similarities include: 1) age of mineralization, ~6000 years to current (Firstova et al., 2016; Johns et al., 2014); and 2) high copper contents, with chalcopyrite dominating sulfide mineralization (Firstova et al., 2016; Lipton, 2012). The reason for high Cu concentrations in both of these locations is still not entirely understood. The youthfulness (<6000y to current) of both locations is important because it reduces the possibility of increased zone refining, allowing us to understand the source characteristics better. This research will advance our understanding of the copper systematics of SMS systems by investigating and comparing the mineralogical and geochemical signatures from two, Cu-rich, end-member type SMS sites."

Jan 1, 2017

By Richard Harrison, Frank Lim

Deepsea Mining will soon become a reality with Nautilus Minerals getting their equipment ready to mine SMS at Solwara 1 off the coast of Papua New Guinea. The vertical transport system (VTS) adopted by Nautilus consists of a riser hanging ‘freely’ from the mining production vessel with a lifting pump unit suspended at its lower end. A compliant jumper connects the pump to the seabed crawler without restraining its movements. In this free-hanging VTS arrangement, the vessel can be re-positioned to follow the crawler should it want to extend the mining area and start stretching the jumper. A recently proposed alternative to this is a free-standing VTS whereby the riser is grounded on the seabed with a base and maintained in an upright position by distributed buoyancy modules or a buoyancy tank at the top. A compliant jumper connects the seabed crawler to the riser base, and another connects the riser top to the vessel. In this free-standing arrangement, the entire VTS can be lifted clear of the seabed for relocation to a new mining area. This paper will describe the important features of the two options and discuss the advantages and disadvantages in respect of riser dynamic behavior, water depth, weather and mining windows, pump maintenance, installation and retrieval, continency measures, etc. The two systems will also be appraised separately for mining SMS and SMnN deposits.

Jan 1, 2018

By Laurie Meyer

The need for improved, high confidence estimates of nodule abundance to support mine permitting, detailed mine planning and mining and processing equipment design is evident. To date, physical samples represent the ?Gold Standard? for nodule abundance measurement, and are likely to remain as such. However, there are some interesting improvements in the area of 3-D scanning which, if marinized for operations at 6000m, may prove to be reliable alternative methods for mapping abundance over large areas particularly if calibrated or benchmarked with physical sample data. . Features of a high confidence physical sampling device, such as the 0.75m2 (0.86m on a side) box corer developed and successfully used by the Kennecott Group for exploration in the CCZ, take into account not only the accuracy in nodule sample collection but a host of other operability considerations which can mean the difference between a successful exploration cruise yielding high numbers of large area samples and one in which few, inaccurate, often inconclusive samples are collected (or, even worse, the sampler fails to grab any nodules for any number of reasons). The collection of physical samples at appropriate spacing within a mine area combined with more qualitative indications of nodule density such as can be obtained using acoustic backscatter should prove adequate for the near term objectives related to overall abundance appraisal or estimates of ?indicated? resource. Looking ahead, exploration cruises will need to yield increasing amounts of data to support development of higher confidence resource abundance estimates to support issuance of mining permits and detailed design of mining plans and equipment. It is likely

Sep 14, 2011

By Laura Moore

The southern shoreline of Monterey Bay, extending from Moss Landing to the Monterey Peninsula, consists of sandy beaches backed by an extensive Flandrian and pre-Flandrian dune complex. This length of shoreline, proximal to areas of urban expansion, is currently being considered for development. For this reason, it is extremely important to understand the variability of beach and dune position along this stretch of coast through time. Previous studies of southern Monterey Bay have documented relatively high erosion rates of 2-8 ft/yr due to a net deficit in the sand budget. Although the sediment transport system in this region is not well understood, estimates for the sediment deficit in southern Monterey Bay range from 200,000 to 1,500,000 yd3/yr. A possible cause of the erosional regime in the southern bay is the removal of sediment by coastal sand mining operations. Based on agency reports and mining permit applications, approximate volumes of sand removed by mining range from 300,000 to 450,000 yd3/yr. These volumes are significant when compared with estimated values for the sediment budget deficit. The sand of southern Monterey Bay, a valuable commercial resource because of its hardness, roundness, amber color and range of usable grain sizes, has been removed from the surf zone, beaches and dunes of Marina and Sand City by four companies since 1906. Information regarding the cross-shore location of sand removal and the exact amounts of sand removal through time is proprietary and poorly documented. However, records documenting the time at which each company commenced and terminated mining do exist. This information suggests that the greatest amount of sand was removed between 1950 and 1968 when three mining companies were operating concurrently.

Jan 1, 1994

By Malcolm Clark, Robin K. H. Falconer

There are a number of likely impacts from mining operations, but a key issue is uncertainty about the environmental effects of sediment plumes created by disturbance to the seafloor and discharge of processed waters. The New Zealand National Institute of Water and Atmospheric Research (NIWA) is undertaking a research project to improve understanding of such impacts (relevant to both mining and trawl fisheries), by examining the extent and persistence of sediment plumes, the immediate impact and subsequent recovery of seafloor exposed to these plumes, and the effect on functioning of ecologically significant species. The project will use a combination of field survey experimentation with in situ observations and controlled laboratory-based experiments. The field work begins in May 2018 when an area of up to 1km2 at depths of 400-500 m on the Chatham Rise, 450 km east the New Zealand South Island will be subjected to disturbance by an upgraded former NOAA Benthic Disturber. The suspended sediment load created by the disturbance will be tracked and monitored, with the effects on seafloor animals examined by pre-and post-disturbance sampling. A wide range of seafloor sampling, benthic landers, towed cameras, oceanographic moorings and water column monitoring will be carried out over a three week period. Monitoring surveys will be repeated in 2019 and 2020 to determine the longer-term resilience and recovery of disturbed communities. The laboratory-based side of the programme, also starting in 2018, involves holding live deep-sea corals and sponges in tanks at NIWA, and exposing them to various levels and duration of particle loads in the water in order to reveal lethal thresholds as well as sub- lethal effects of settled and suspended sediment.

Jan 1, 2018

By Ulrich Von Stackelber

Deep sea mining of manganese nodules actually will have an environmental impact to the seafloor and to the water column. However, we are far from being able to predict the possible consequences. Therefore, in 1992 environmental studies were conducted with the R/V Sonne in a manganese nodule field of the Peru Basin. The bathymetry of the seafloor was mapped using the hydrosweep system and the distribution and type of sediments were investigated by the parasound system and by collecting surface samples and sediment cores. Deep towing of a side-scan sonar system revealed a Mn encrustation of sediments and a nodule coverage of variable density. Along the tracks of a photo sledge a great variability of bottom fauna and of bioturbation was observed. Bottom-mechanical investigations of surface-near sediments were completed on board. Additionally water samples were collected near the sea floor to determine character and amount of dissolved and suspended particles. Manganese nodules and crusts were collected at 80 locations. In many aspects the nodules differ from those of the Clarion-Clipperton Zone: Big cauliflower-shaped nodules with growth rates up to 160 mm/ Ma may reach a maximum size of 24 cm in diameter, maximum abundance may be 44 kg/m2, the mean size of buried nodules is greater than that of surface nodules. The reason for that difference is due to the relatively high bioproductivity in surface waters and to a Mn redox boundary in the sediment column 10 cm below the seafloor. Histograms of nodules showing the distribution of size and growth type clearly indicate that the growth history is different for basins, slopes and tops of seamounts and ridges. Nodules with diameters >7 cm show mainly diagenetic and to a minor degree hydrogenetic growth. Smaller nodules of the same assemblage are composed mainly of hydrogenetically grown Mn oxide. The optimum diagenetic growth occurs within the sediment immediately above the Mn redox boundary, a level which is not reached by the small nodules.

Jan 1, 1994

By Kris van Nijen

IHC Merwede, a Dutch supplier of ships and equipment for dredging and mining activities, and DEME, a Belgian dredging and environmental services group, will enter into a joint venture for deep-sea mining activities. Under their cooperative agreement, IHC Merwede will be responsible for the development and construction of technical solutions, while DEME will be responsible for operations. Together the companies will offer a unique pioneering total solution. The joint venture will be known as OceanflORE.

Jan 1, 2011

The chemical composition of the nodules varies with the type of manganese minerals and the size and characteristics of their nucleus but those who have an economic interest have nucleus, generally : Mn> Fe> 6> Si> Al> Ba> Ni> Cu > Co. The Pacific Rim is an area of abundant occurrence of polymetallic nodules and the Pacific sea floor of the Clarion-Clipperton Zone (CCZ) is one of the most interesting areas in regard to the genesis of polymetallic nodules. Their abundance in the ocean floor is very variable, as there are places where they cover more than 70% of the ocean floor. The nodules can be found at any depth, but the highest concentrations are between 4000 and 6000. Hydrothermal processes that occurs near the East Pacific Rise at 21° N, may inputs metallic elements to nodules and to pelagic sediments, especially in regions close to the dorsal, as a greater influence hydrogenetic processes are present westward Metals such as Cu, Co, Ni, Sn, Fe, Mg, Pb, Zn and Ba show a relationship with the East Pacific hydrothermal activity and sea currents carry these metals in solution to the Clarion-Clipperton fracture area, where there are hydrogenic metals sources (Al, Fe and Mn).

Sep 14, 2011

By S. Kim Juniper

Ocean observatory technologies permit uninterrupted, real-time observation of dynamic seafloor environments such as gas hydrate deposits and hydrothermal vent fields that are of both scientific and economic interest. Such observations enable new discoveries of linkages between physical, chemical and biological processes and could permit continuous monitoring of environmental variables during mining operations. Ocean Networks Canada operates the NEPTUNE and VENUS cabled observatories in the Northeast Pacific Ocean. The offshore NEPTUNE observatory supports instruments at two gas hydrate sites on the continental margin off Vancouver Island, and in the hydrothermal vent fields of the Endeavour segment of the Juan de Fuca Ridge. The primary focus of the gas hydrate field observations is to understand the dynamics of the growth and stability of outcropping and sub-seafloor hydrate deposits. Outcropping hydrates at 840 m depth in Barkley Canyon have been monitored for the past 3 years with a mobile instrument platform known as Wally, which is operated over the Internet by a research group in Germany. This tracked vehicle carries standard oceanographic sensors, acoustic current metres, cameras and methane sensors. Data indicate a relationship between degassing of hydrates and tidal currents. In 2012-2013 two high-resolution sonar towers were added to the hydrate field to provide precision tracking of Wally and to monitor volume changes in the outcropping hydrate mounds. A large subsurface hydrate deposit occurs at the Clayoquot Slope site, where bottom depth is 1260 metres. Monitoring instrumentation is currently being established at this location. Gas bubble release from this deposit is being monitored by a sector scanning sonar mounted on a

Sep 14, 2011

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 Georgy Cherkashov, Livia Ermakova

Active development of the exploration and further exploitation of deep-sea minerals requires special emphasis on the protection of the marine environment. The complexity of this subject lies in the fact that potential impact and effects of future mining activity are not completely known. One of the main sources of potential impact near the seafloor, as it expected, would be a generation of sediment plumes, their dispersion and redeposition of sediment. Meanwhile, their dimensions, rates of dispersion and redeposition are a big issue. Other plumes are expected in the surface layer as a result of discharges of processing waters and particles after sorting on board of mining vessel, and their features are also not clear. At the same time, understanding of these aspects would be crucial for definition of environment impact area, delineation and designation of different types of protected areas (Areas of Particular Environmental Interest, Impact and Preservation Reference Zones) and future assessment of environmental impacts. Attempts to address these issues demonstrated wide variations between the data of field experiments on the one hand and the results of analytical and numerical models on the other. According to in situ measurements, plumes were detected at a distance vary from one to less than 20 km [e.g., Burns et al., 1980; Sharma et al., 2001; Nautilus Minerals, 2008 etc.], whilst some models show results up to 100 km [Rolinski S. et al., 2001] and more. It seemed that results of in-situ experiments are preferable, but they were not many indeed. However, these data were used in different investigations rather widely, but their focus, as far as we know, was not on the matters related directly with plumes.

Jan 1, 2018

By Francois P. Leroy

In the quest of studying the assigned blocks of seafloor for deep water mining, each member country of the ISA is thirsty for accurate information as to the level of resources available. Manganese nodules represent a large portion of the resources and are as precious as they are hard to locate and harvest. Resolving such challenges is what drives the technology development and yields instruments and products capable of serving this field of research. This presentation will study how manufactures of oceanographic instruments have pushed the technology envelop to in order to transform a collection of sensors and instruments into a seamless and adapted assembly working to serve the researcher and prospector in the challenging field they operate. Deep water data collection is characterized by the following challenges: ? Deployment, recovery and handling of the vehicle ? Producing high resolution at great distances ? Positioning that data with accuracy to relocate Teledyne Marine will present the work performed in its engineering laboratories to produce sub systems and systems now capable of delivering key information necessary to the proper cataloguing and exploitation of deep water mineral mining. Understanding and controlling the alternative resources available to each country will allow better management of current traditional land based minerals.

Jan 1, 2010

By Hans Smit

The face of mining as we know is changing as mining companies all over the globe realize the reality of accessing the vast mineral wealth contained on, and under, our ocean floors. With some land based mineral deposits being fully exploited across the world, deep sea mining is set to revolutionize global approaches to the search for precious metals and other sought after minerals. Previously, the financial and technological implications of deep sea mining outweighed the benefits of access to the mineral rich deposits identified all around the world. The process of marine diamond mining off the west coast of southern Africa started in the late 1950s, and subsequently continued by De Beers to the present day, has proven to be an excellent proving ground for the development of technology and mining systems that ensure a sustainable and financially viable business.

Jan 1, 2011

By M. Ravindran

The Government of India started its deep seabed exploration programme during 1982. This programme was started as one of national importance and several national laboratories were involved to realize the development of requisite technologies for deepsea mining and processing. After a concentrated effort on surveying, using its own as well as hired ships, India succeeded by mid 1980s in identifying a prospective site in the Indian Ocean as an exclusive claim for development. India was registered as a Pioneer Investor and became the first country to obtain this status on 17th August 1987. India has been allocated an exclusive mine site of 150,000 km2 in the Central Indian Ocean. Our country also developed considerable expertise in the metallurgical processing for extracting metals from these nodules. The Department of Ocean Development, Government of India, the organization which is designated as the nodal agency responsible for implementing the deep seabed mining programme has drawn up a long term plan which will enable it to fulfill its obligations as a Pioneer Investor. The work toward the design and development of a mining system has been entrusted to the Central Mechanical and Engineering Research Institute, Durgapur. As a part of this programme they have developed a nodule collector and a riser system which have been tested in very shallow waters only. Since this technology development for deep sea mining applications is highly time consuming and very expensive, this programme is also being used to develop components for intermediate applications. In view of the long timeframe required for perfecting a deepsea nodule mining technology, the Government of India is also keen on developing shallow water mining systems for utilizing the placer deposits. One of the richest heavy mineral deposits in the Indian Exclusive Economic Zone is available on the west coast of South India in the state of Kerala. The coastal stretch between Kanyakumari, on the southern tip of India, and Alleppey along the west coast at a distance from the tip of approximately 210 km, there is a good multimineral reserve. The initial survey indicates that the estimated reserves in the surveyed areas are approximately as follows: Ilmenite 1.4 million tonnes Rutile 0.14 million tomes Zircon 0.13 million tomes Sillimanite 0.53 million tonnes

Jan 1, 1994

By R. D. Hamer

"The Atlantis II Deposit comprises metalliferous sediments (Zn+Cu+Ag+Au) accumulating in a composite, axial basin, 2,000m beneath the surface of the Red Sea. The basin contains warm, highly saline water. It is located approximately half way between Jeddah and Port Sudan within the Exclusive Economic zones of Saudi Arabia and Sudan. The Deposit was discovered in 1963 and evaluated by drilling in the 1970s and 1980s. This phase defined an initial resource of approximately 90Mt. More recent estimations have refined this figure to an Inferred Resource of approximately 80Mt (CIM compliant).The Mining Licence to develop and extract the Atlantis II Deep Deposit was granted to Manafai International Trade in 2010 by the joint Saudi-Sudanese Red Sea Commission. Manafai is poised to embark on a renewed phase of exploration and evaluation, including the completion of a Definitive Feasibility Study (DFS) and leading to the successful exploitation of the Deposit in a safe, environmentally sound, economically viable and socially responsible manner.The Deposit is forming in a complex basin adjacent the median rift, where sea floor spreading has operated during the last 5Ma. It is a Hydrothermal-sedimentary Deposit. The mineralised sedimentary rocks rest directly on sea floor basaltic rocks. They are produced by the exhalation of metal-rich, hydrothermal brines from fissures associated with the central rift and cross-cutting fracture zones. Up to 25m of metal-rich sediments have accumulated over an area exceeding 57km²."

Jan 1, 2017

By C. Wildman

Prospectivity modeling of seafloor massive sulphide (SMS) deposits has been completed over the Kermadec Arc-Colville Ridge area using the GIS based weights of evidence and fuzzy logic modeling techniques. SMS deposits are the current equivalent of ancient onshore volcanogenic massive sulphide (VMS) ore deposits. These high-grade deposits are formed on the seafloor and commonly consist of a black smoker and metal rich sediment mound complex resulting from the discharge of hydrothermal fluids (up to 400°C) from fractures on the seafloor. Metal sulphides are continuously precipitated in response to mixing of high-temperature hydrothermal fluids with ambient seawater. Accumulation of metal sulphides has led to SMS deposits being potentially major sources of copper, zinc, lead and other metals such as gold, silver, which to date remain untapped. Modeling of SMS deposits was undertaken to illustrate the power of GIS modeling for seafloor resource evaluation and how it can be used to quickly identify and rank in terms of the most likely prospective areas of the seafloor where new SMS deposits might exist. The mineral deposit modeling was constrained by the mineral systems concept which defines those parts of a mineralisation system that are critical to the ore-forming process. The deposits are typically formed in extensional tectonic settings, including both submerged tectonic margins and sea-floor spreading. Volcanic vent systems and underlying dykes, stocks and sills are the sources of heat that are responsible for converting sea water drawn down through fractures in the oceanic crust into an ore-forming hydrothermal fluid. This fluid is then capable of leaching metals and elements from surrounding footwall rocks, which are then transported upwards via the convection of hydrothermal fluids. The ore materials are then precipitated within the black smoker field as massive sulphides due to the mixing of high-temperature (250-400°C), metal-rich hydrothermal fluids with cold (about 2°C) oxygen bearing seawater.

Jan 1, 2011

By Tao Chunhui

The seabed deposits type and distribution are very complex at the hydrothermal field. In this paper, we provided an approach to study the seabed deposits classification at the Precious Stone Mountain hydrothermal field (PSMHF) using MultiBeam sonar data . The PSMHF was found in the Galapogas microplate at the Leg 3 of the Chinese COMRA 21st Cruise. Using this approach, the seabed deposits at the PSMHF are mainly classified into three types, which are rock, breccia and sediment, respectively. We can find the distribution of the three types of seabed deposits according to the sonar backscatter data. The rocks are mostly distributed around the hydrothermal vent. The breccia are located at the foot of the vent. Most sediments are distributed at the southwest to the vent due to bottom current. Combining with seabed video, TV-Grab sample and the backscatter data, we draw the map of the seabed deposits distribution at the PSMHF.

Sep 14, 2011