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By Jan M. Peter

Many of the Pb-Zn massive sulfide deposits of the Bathurst area in northern New Brunswick, Canada, are intimately associated with laterally continuous iron formation (IF) (Figure 1). This IF is a fossil laminated, exhalative, chemical sediment. Together, the IF and the Brunswick #12, Brunswick #6, and Austin Brook deposits (rightmost discontinuous horizon on Figure 1) are collectively referred to as the "Brunswick Belt". To date we have only studied the Brunswick Belt and have not examined the horizon along which the QSR, CNE and Flat Landing Brook deposits lie. The Bathurst area is underlain by the Tetagouche Group (Figure 2), a Cambro(?)-Ordovician sequence of metasedimentary and bimodal metavolcanic rocks that was intruded by mafic to felsic plutons and subsequently deformed during the Taconic Orogeny. The stratigraphic sequence consists of shales and greywackes that are overlain by carbonaceous shales and felsic volcanic and volcaniclastic rocks; these are in turn overlain by mafic volcanic and sedimentary rocks. The massive sulfide deposits and IF occur within the upper portions of the felsic volcanic rocks in close association with carbnaceous metasedimentary footwall rocks (Figure 2).

Jan 1, 1993

By Kira Mizell, James Hein

"INTRODUCTIONThe majority of studies on the genesis of ferromanganese crusts focus on the adsorption and accumulation of metals, and therefore cations, especially those of economic interest. From these studies, a first-order electrochemical model has been proposed based on the zero point of charge of the manganese and iron oxides at typical seawater pH, which assumes that positively charged ions will bind to the negatively charged manganese oxide phase and neutral and negatively charged ions will bind to the slightly positively charged iron oxide phase (e.g. Koschinsky and Halbach,1995; Hein et al., 2013). While the theory behind this model is sound, and it has been consistent for many elements, other elements may not follow the model (Koschinsky and Hein, 2003), and thus requires additional investigation and validation. As a new approach to understanding element accumulation in ferromanganese crusts and to test the proposed electrochemical model, this study investigates the surface chemistry of the halogens, which occur as negatively charged ions in seawater and have high and consistent concentrations in seawater.ResultsBulk Halogen ConcentrationsTo determine the distribution of halogens in ferromanganese crusts, an initial dataset of 24 FeMn crusts (24 bulk and 19 layer samples) from throughout the global ocean, including the Arctic and the Southern Oceans, has been analyzed for chlorine and fluorine content using ion-selective electrode. Although both Cl and F are conservative in seawater, their content in crusts shows striking variability (Cl: 326 - 13310 ppm; F: 146 – 1048 ppm for non-phosphatized crusts) and has no obvious geographic relationship to ocean basin and no correlation with water depth, latitude, or longitude. We plan to have bromine concentration data to present at the time of this conference."

Jan 1, 2017

By T. Barryere, R. B. Pedersen, E. Reeves, A. Stensland, I. Thorseth, T. Baumberger

Venting on ultraslow spreading ridges is far more abundant then previously predicted, and the discrepancy between observed and predicted vent field density may imply that non-magmatic heat sources are common along these ridges (Baker and German, 2004; Escartin et al., 2008; Rona et al., 2010; German et al., 2016). In this study we have estimated the flux from two hydrothermal vent sites situated on the slow to ultraslow spreading Mohns Ridge at the Arctic Mid-Ocean Ridge system (AMOR). The flux estimates have been made using the primordial isotope 3He in the non-buoyant plume above the Loki’s Castle vent field at the northern termination of the Mohns Ridge, and from the Jan Mayen vent fields area situated close to the southern termination of the ridge. Primordial 3He enters the oceans through degassing and mixing with hydrothermal fluids eventually to be discharged at the ocean floor primarily at hydrothermal vent sites and submarine volcanic eruptions (e.g. Clarke et al., 1969; Lupton and Craig, 1981; Lupton, 1998). Once introduced into the water column the concentration will only decrease by dilution due to its conservative behavior in the water column. Water column samples were collected using a CTD (conductivity, temperature, depth) probe (911plus Seabird) with a Niskin water bottle rosette. The water column above the Jan Mayen vent fields (JMVF) was sampled in the years 2006, 2011, 2012 and 2013 (82 samples) and the water column above the Loki’s Castle vent field was sampled in the years 2007, 2008 and 2009 (116 samples).

Jan 1, 2018

By Charles W. Finkl

Coastal and marine aggregate (sand and gravel) mining on US continental shelves is a major activity that supplies industrial and commercial demands for these raw materials. Because Pacific, Atlantic, and Gulf coasts contain significant shoreline segments that are in a critical state of erosion, sand-gravel and mixed sediment (sands with a high percentage of silt-plus-clay) deposits are mined in efforts to mitigate land loss. Sandy shores, and to a limited extent gravel coasts, erode by shoreline retreat due to relative sea-level rise and sediment starvation in littoral drift patterns. Mostly gravel shores occur in high latitudes and shorelines often advance seaward due to isostatic rebound following the LGM (Last Glacial Maximum 18,000 YBP). Sandy and fine-grained shores occurring in middle and low latitudes of the conterminous United States are problem coasts that require beach renourishment and reconstruction of barrier islands. Muddy coasts of the Mississippi Delta region are especially problematic because some islands are literally disappearing in response to subsidence. Replacement of sediments lost to the littoral drift system or returned to sedimentary sinks by drowning is thus a critical endeavor that involves annually dredging hundreds of millions of cubic meters of sediments from the continental shelf area. The types of shelf sediments that are amenable to marine mining techniques, their occurrence, and means of detection are highlighted in this paper. Minable Sediments on the Continental Shelf Wide varieties of sedimentary bodies that occur on the continental shelf are amenable to mining for beach renourishment and barrier island (beach-dune-marsh system) reconstruction. Relict terrestrial deposits make up a small but important proportion of shelf sediments that were deposited on coastal plains, now drowned by the post-glacial sea-level rise to form continental shelves. Examples of these deposits include drowned moraines, outwash plains, eskers, and kettles along the northern Atlantic coast in addition to siliciclastics along middle latitude Pacific, Atlantic, and Gulf coasts. Special cases include carbonate sequences along tropical costs of Florida and the muddy coasts of deltas, mostly in Louisiana. Specific types of minable deposits thus include shoreface attached sand sheets, dunes, and ridges in addition to offshore inter-reefal sands (between coral reefs in the Florida Reef Tract), bank deposits, and sand waves (ridges) that extend into US territorial waters. Nearshore siliciclastics include ebb-tidal deltas and bars. Drowned river valleys occur along all three US coasts and can be exploited for their fluvial sands if the covering mud sheets are thin.

Jan 1, 2005

By Lee Sung-rock

KIGAM (Korea Institute of Geoscience and Mineral Resources) has been doing various kinds of research works in marine minerals and energy resources exploration and utilization since early 1990s in Korea. In the presentation, the authors will introduce the recent research and development activities mainly focusing on the rare earth metals of the Pacific deep seabed Mn-nodules and gas hydrates which occur from Korean deep waters. KIGAM has been participating in the polymetallic manganese nodule exploration, mining and metal-extraction project, which is modulated by KIOST (Korea Institute of Ocean Sciences and Technology, formerly KORDI). Now KIGAM puts more focus on extracting precious and rare earth metals from the Mn-nodule as well as underlying sediments. The rare earth elements (REE) from seabed mineral deposits also draw attention to those countries including Korea which are lack in natural resources. KIGAM is doing several kinds of leaching experiments using various kinds of reagents under the different experimental parameters. Extraction of rare earth metals from deep sea nodule using H2SO4 and HCl solution showed good leaching effect. As the gas hydrates are to be evaluated as a new future energy resource globally, Korean government has initiated national R/D program covering fundamental exploration survey for resources assessment in Korean deep waters and production technology development. KIGAM plays a key role in seismic exploration, resources assessment, experimental

Sep 14, 2011

By Brian D. Bornhold

A comprehensive multi-disciplinary marine geological survey of northwestern Graham Island, Queen Charlotte Islands, British Columbia, Canada was conducted by Offshore Survey and Positioning Services Ltd. of Vancouver, B.C. on behalf of the Geological Survey of Canada; Energy, Mines & Resources Canada, Pacific Geoscience Centre, Sidney, B.C. Canada during October 1984 and July 1985. The aim of the survey was to map both the surficial geology and geomorphology in order to identify and evaluate the nature of the nearshore sedimentation and recent tectonics including stability (slumps and scarps) seafloor faults (frequency and displacements) and both the classification and consistency of soil type boundaries and properties. Data was acquired by utilizing conventional indirect applied marine geophysical techniques including side scan sonar, precision echo sounding and complimentary soil sampling. During October 1984 a total of 320 line kilometres of data including 180 soil samples were acquired. During July 1985 a total of 300 line kilometres of data were acquired including 150 soil samples.

Jan 1, 1985

By Cees van Rhee, Rudy Helmons

INTRODUCTION Seafloor Massive Sulphides are typically found near the oceanic ridges at larger water depths (>1km). The physical properties of SMS, as shown in table 1, are comparable to the properties of weak rock. One of the technical challenges to enable extraction from these locations is the cutting or excavation process. Experiments have shown that the energy needed to excavate the material may increase with water depth (Alvarez Grima et al. 2015). Besides that, it is demonstrated that rock that fails brittle in atmospheric conditions can fail more or less in a plastic fashion when present in a high pressure environment, as would be the case at large water depths. The goal of this research is to identify the physics of the cutting process and to develop this into a model in which the effect of hydrostatic and pore pressures is included. The cutting of rock is initiated by pressing a tool into the rock. As a result, at the tip of the tool a high compressive pressure occurs, which leads to the formation of a crushed zone. Depending on the shape of the tool and the cutting depth, shear failures might emanate from the crushed zone, which will eventually expand as tensile fractures that can reach to the free rock surface. Through this process intact rock will be disintegrated to a granular medium. For an overview of the process (figure 1). Additionally, the presence of water in the pores of and surrounding the rock influences the cutting process through drainage effects. The most relevant effects are weakening when compaction and strengthening when dilation occurs in shearing and tension. Deformation of the rock causes the pore volume to change, resulting in a under or over pressure. As a result, the pore fluid needs to flow. The magnitude of the potential under pressure is limited through cavitation of the pore fluid, limiting further reduction of the pore pressure (figure 2). The drainage effects cause the rock cutting process in a submerged environment to show a stronger dependency of both the hydrostatic pressure as well as the deformation rate (figure 3).

Jan 1, 2018

By Harold Gibson, Ulrich Schwarz-Schampera, Ralf Freitag, Hendrik Mueller

INTRODUCTION Germany has a long history in marine research in the Indian Ocean. The first German scientific cruise started in 1964, followed by a series of state-sponsored research cruises between 1983 and 1995 leading to the first finding of polymetallic sulfides in the Indian Ocean. The research included regional bathymetric, geological, structural, volcanological, petrological and hydrothermal investigations along the Carlsberg Ridge and the Central Indian Ridge (CIR). Early environmental base line studies covered oceanographic and sedimentology aspects. In 2010, BGR took the initiative for the preparation of a license application for the exploration of polymetallic sulfides with the International Seabed Authority (ISA), and prospecting started in 2011 along the southern Central (CIR) and the northern Southeast Indian Ridge (SEIR) in the southwestern Indian Ocean (cruises INDEX 2011 on board R/V Sonne), INDEX 2012 (R/V Fugro Gauss), INDEX 2013/1-2 (R/V Sonne) and INDEX 2014 (R/V Pelagia). After three years of resource-oriented and environmental base line studies, BGR, in order for the Federal Ministry for Economic Affairs and Energy (BMWi), applied for an exploration license which was approved by and subsequently signed with the ISA in 2015. The license gave permission to start a detailed exclusive resource-oriented exploration program in the license area. The program includes the outline of potential ore deposits and a resource assessment but also extensive and detailed base line studies for the sustainable protection of the marine environment in the license area. The license contract has a fifteen years lifetime and may allow the application for a subsequent mining license. The exploration aims at the identification of inactive polymetallic sulfide deposits, formed below former discharge zones of hot hydrothermal fluids on the ocean floor (“black smoker” systems), by advanced and modern exploration techniques.

Jan 1, 2018

By Ulrich Schwarz-Schampera

Submarine hydrothermal vents and associated mineralization on the Tonga arc have been identified in the summit calderas of two shallow-water volcanoes. The highest temperature vents (up to 270°C) occur at water depths between 430 and 540 meters below sea level (mbsl) near the summit of one volcano at 24°S (volcano 19). Clusters of large barite, anhydrite, and sulfide chimneys on the summit cone are vigorously discharging clear hydrothermal fluids with temperatures on the seawater boiling curve. There is abundant evidence of phase separation and associated gold and base metal precipitates. Pyrite, marcasite, wurtzite-sphalerite, tennantite, and chalcopyrite line the interiors of the highest temperature vents. Acid-sulfate alteration of basalts and basaltic andesites is evidenced by intense silicification and the presence of abundant alunite. One volcano at 21°S (volcano 1) has a chain of explosion craters on the flank of a neovolcanic scoria cone and associated massive pyrite, barite and native sulfur deposits at a water depth of 210 mbsl. Intergrowths of pyrite and enargite are associated with intensely argillic altered basaltic andesites. The reported alteration and Au-enriched mineralization styles of these vent fields are similar to other shallow water hydrothermal systems at island arc volcanoes and contribute to the diversity of seafloor hydrothermal activity in the western Pacific region.

Jan 1, 2010

By Timm Schoening, Greinert. Jens, Iason –. Zois Gazis

"Ferromanganese nodules are again of interest because of their high concentrations of Ni, Co, Cu as well as REE. With regards to an operational underwater mining industry, one of the main questions and important requests is to finding a method that can predict the abundance of nodules with high accuracy within reasonable time spans, without many requirements for ground truth data; and all these on an operational scale and ideally automated. In this regard, we present results of a study based on the combination of highresolution multibeam and optical data acquired by an AUV using specific machine learning techniques to reveal a detailed distribution of the Mn-nodules in correlation to the seafloor terrain. The accuracy of the method employed and results gained were validated and approved through comprehensive statistical analysis and by comparison to box-core data.Study AreaOur study area (AUV survey block G77) is located in the Clarion-Clipperton Zone (CCZ) (Eastern Central Pacific Ocean), an area that has been receiving international research and industrial attention for many years already (e.g. McKelvey et al., 1979; Bernhard and Blissenbach, 1988, von Stackelberg and Beiersdorf, 1991, Jeong et al. 1996). Block G77 covers an area of 9.5km2 in a depth between -4478m and -4536m. The area is characterised by gentle slopes 0-5° (0-3° in most of the area and only in the outer parts of the Block slopes can exceed 5°). The seafloor is characterised by moderate to low rugosity, the only exception being a small area in the eastern part, where sub-recent smallscale volcanic activity created 15 cone-shaped morphological features of up to 55m height and 150m width that are clustered in an area of 700 x 380m (Figure 1)."

Jan 1, 2017

By Satya Nandan

• A review of the structure and mandate of the Authority – its main functions. • The different types of mineral resources found in the deep seabed – their global distribution. • The Development of Regulations for Prospecting and Exploration of Polymetallic Nodules, Cobalt-Rich Crusts and Polymetallic Sulphides including environmental regulations and guidelines. • Early constraints for deep seabed mining – Improving conditions for mining – Future prospects for mining.

By Will Roberts, M. E. Williamson

After verification of methodology and testing of prototype systems during 2005/06, Nautilus Minerals expanded their Papua New Guinea (PNG) operations to a full commercial exploration program in 2007. Included was the deployment of sensors and survey systems to locate, characterize and verify massive sulfide deposits with potential as mine sites within the tenements held by Nautilus in PNG. This presentation discusses some of the gear developed and operated during the 2007 PNG investigation.

By Robert G. Ditchburn, Albert Zondervan, Akira Usui, Hiroshi Shibasaki, Hajime Hishida, Ian J. Graham

Earlier reconnaissance geological survey and recent mineral exploration by the Geological Survey of Japan (now part of AIST), Metal Mining Agency of Japan (now part of JOGMEC) have revealed that hydrogenetic ferromanganese crusts are widespread over rock outcrops of the floor of the NW Pacific Ocean, south and east of the Japanese Islands, despite vigorous tectonic activity, such as subduction and backarc spreading. Deposition of ferromanganese oxides has occurred since at least the mid-Paleogene over the Philippine Sea Plate region and nearby.

By Steven D. Scott

A geologist can be likened to a medical pathologist trying to figure out from faint clues how something had lived and how it died, often long after the event. Present-day seafloor hydrothermalism has empowered geologists/pathologists to dissect a living system, in this case volcanogenic massive sulfides (vms) deposits of copper, zinc, lead, silver and gold. On the other hand, a considerable amount of our understanding of seafloor hydrothermal processes and its products stem from our knowledge, much of it from industry, of these same processes and products that formed ancient ores in oceans as much as 2700 million years ago and are now mined on land.

Aug 24, 2006

By Akira Usui, James R. Hein, Rachel Dunham

Ferromanganese crusts are found on most hard-rock substrates in the deep ocean (800-3,000 m). Their distributions on seamounts are complex and controlled by a wide-variety of factors including seamount morphology, current patterns, mass wasting, substrate rock type and age, subsidence history, and others. However, the development of this potential resource ultimately depends on this distribution, as well as on the small-scale topography, grade, and tonnage. The parameters that will ultimately be used to define a mine site are unknown, but reasonable assumptions based on 25 years of data collection can be used to bracket likely permissive characteristics.

By Luana Karvel, Lars Kullerud, Morten Sørensen, Øystein Halvorsen, Øivind Lønne, Elaine Baker, Tina Schoolmeester, Joan Fabres, Yannick Beaudoin

The UNEP Shelf Programme (USP) is the access point for a collaboration of international organizations with expertise in marine geoscience and maritime law. It was established in response to a United Nations resolution, stating that the United Nations Environment Programme (UNEP), working through the Global Resource Information Database (GRID) system, should work in conjunction with Intergovernmental Oceanographic Commission of UNESCO (IOC) and the International Hydrographic Organization, to assist coastal States, and in particular developing States and small island developing States (SIDS) with submissions to establish the outer limits of their continental shelf under Article 76 of the United Nations Convention on the Law of the Sea (UNCLOS).

By Alan Foley

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

Sep 24, 2006

By Evgeny G. Gurvich

While direct study of high temperature hydrothermal activity and the associated mineral formation as well as study of their scales are possible in the modern ocean, researchers are deprived of such opportunity for past geologic time. Even in cases where hydrothermal deposits that formed in the geological past are preserved they have been covered by sediments or overlain by lava and have become inaccessible after a time for obser-vation and sampling. Rarely are these buried hydrothermal deposits found during deep-sea drilling or coring operations, and their direct study on an ocean scale is impossible at present. Even within hydrothermal fields, without special preliminary detailed surveys, the probability of intersecting hydrothermal edifices that are covered by sediments becomes a rare event.

Aug 24, 2006

By Nobuyuki Okamoto, Bhaskar Rao

For a period of twenty years - from 1985 to 2005 - the Japan Oil, Gas and Metals National Corporation (JOGMEC) and Pacific Islands Applied Geoscience Commission (SOPAC) have jointly conducted surveys of deep-sea mineral resources in the EEZs of SOPAC’s twelve member countries. The overall Programme has obtained excellent results and has identified numerous sites with potential marine mineral resources of manganese nodules, cobalt-rich manganese crusts, and polymetalic massive sulphides. The survey cruises have identified numerous sites with potential marine mineral resources such as: manganese nodules in the Cook Islands; cobaltrich manganese crusts in the Marshall Islands, FSM, and Kiribati; and polymetalic massive sulphides in Fiji. Based on collected samples and acoustic data, inferred resources for manganese nodule, cobalt-rich manganese crusts, and polymetalic massive sulphides, have all been estimated to be about- 200 million tons in the central Cook waters- 200 million tons in the three seamount selected Marshall waters- and 500 thousands tons around the triple junction of the North Fiji Basin.

Oct 15, 2007

By Yanis Miezitis, Gerald Mueller, Timothy F. McConachy, Ronald G. Sait, Keith R. Porritt, William J. McKay

In November 2004, Australia lodged with the United Nations Commission on the Limits of the Continental Shelf possible new maritime boundaries in relation to Australia’s continental shelf extending beyond 200 nautical miles from the Territorial Sea Baseline (Colwell and Symonds, 2005). If agreed by the commission, just over half of Australia’s land mass will lie below the sea, and Australia will have one of the largest marine jurisdictions in the world (14.41 million km2). With this jurisdiction comes a responsibility to manage and sustain the marine environment (McConachy, 2006). Knowledge of minerals and their resource potential is part of this responsibility but is generally poorly known (McConachy, 2005).

Aug 24, 2006