Search Documents

By Colin Devey

As marine research scientists we especially appreciate the uniqueness and complexity of the deep-sea hydrothermal vent fauna and environments, and are particularly interested in preserving vents for their scientific, aesthetic, ecological, and potential economic values. In fact, because of the specialized nature of the equipment required to work at deep-sea hydrothermal vents, such as occupied and unoccupied research submersibles, scientists are the primary group of people who have the opportunity to visit these extraordinary environments. The potential for significant impact of scientific activities on a single vent site or a population of vent animals pales in comparison to the potential for disturbance by volcanic/tectonic events or industrial mining/harvesting activities. Nonetheless, we recognize that some scientific activities could adversely affect individual sites or impact communities more than is necessary, if research activities are not carefully planned and executed. In addition, because only a limited number of sites are currently known and scientists from a wide variety of disciplines frequently work at single locations, we recognize the potential for use conflicts among scientists, at sites where scientific activity is intense.

Aug 24, 2006

By W. H. Pelton

Polymetallic sulphide (PMS) deposits have recently been discovered associated with hydrothermal vents on the sea floor off Vancouver Island, B.C. Visual estimates indicate reserves in excess of 1 million tons. Reliable reserve estimates have not yet been made, however, due to the extreme difficulty of drilling cores in 2 km of water. Few geophysical techniques can aid in the exploration of these deposits. There is little or no difference in radioactivity, magnetic susceptibility or electrical resistivity between the deposits and the surrounding sea floor sediments. This precludes radiometric, magnetic, electromagnetic and resistivity methods. There is a density contrast, but the logistics of gravity surveys at such depths are formidable. The physical property which shows the most contrast with the sea floor sediments, and which is perhaps one of the easiest to measure (with modern equipment) is polarizability. The induced polarization (IP) method is one of the major electrical geophysical techniques for exploring for PMS deposits on land.

Jan 1, 1985

By Bonnie A. McGregor

The U. S. Geological Survey in cooperation with the Institute of Oceanographic Sciences (IOS), U.K., conducted a sidescan sonar survey of the U. S. Exclusive Economic Zone in the Gulf of Mexico from August 7 to October 22, 1985. A reconnaissance-scale view of 120,000 square nautical miles of sea floor seaward of the shelf-edge was obtained by using the GLORIA (Geologic Long-Range Inclined Asdic) sidescan sonar system. After these data were merged with GLORIA data from an earlier survey (1982) of the northwestern Gulf, a preliminary mosaic was constructed at a scale of 1:375,000. From this mosaic, we can identify morphologic features and interpret sea-floor processes. The extensive deformation of the continental slope seaward of Texas and Louisiana by salt tectonics has resulted in a complex pattern of basins and salt dome highs. One continuous meandering channel was identified in this portion of the Gulf, extending from the shelf edge to the Sigsbee Abyssal Plain. Bottom currents have reworked the sediments in this channel's levees seaward of the Sigsbee Escarpment, the seaward edge of the salt front, suggesting that this channel may no longer be actively transporting sediment. Talus appears to lie along the base of the Sigsbee Escarpment, suggesting that erosion and deposition is occur- ring along this front. Three other discontinuous channel systems can be identified on the mosaic and appear to have contributed sediments to the deep Gulf.

Jan 1, 1986

By Simon McDonald

The Neptune Group was established in 1999 to apply for exploration permits within New Zealand’s 200nm EEZ. These applications were to investigate and commercialise hydrothermal Seafloor Massive Sulphide (SMS) deposits identified by international researchers and to locate others. SMS are volcanically related seafloor accumulations of copper, lead and zinc with high levels of gold and silver. Neptune has three granted exploration licenses within the New Zealand EEZ and has application in other jurisdictions. Neptune undertook the world’s first commercial drilling exploration work of SMS in December of 2005.

Aug 24, 2006

By Virginie Tilot de Grissac

This project funded by Government of Flanders (Belgium) and coordinated by the Intergovernmental Oceanographic Commission proposes to draw recommendations for conservation of the biodiversity and for minimizing the impact of future nodule mining from the description of the referential state of suprabenthic megafaunal assemblages within a nodule ecosystem in the Clarion-Clipperton Fracture Zone (CCFZ). The description of this specific ecosystem is based on the analysis of about 200 000 photographs and some 55 hours of film collected by French and American exploratory cruises. The video and hotographic sampling has been achieved by means of different towed and remote control devices designed for Ifremer and NOAA including the manned submersible “the Nautile.”

Aug 24, 2006

By Michael Johnston

Nautilus Minerals is exploring for high-grade gold, silver, copper, and zinc-rich submarine massive sulphide deposits (SMS) within the territorial waters of the sovereign state of Papua New Guinea. Work to date has shown that these systems contain spectacularly high metal grades. To date a total of 88 surface sulphide grab samples have been collected from Nautilus’ Solwara 1 Prospect within EL 1196 in the Manus Basin, returning average grades of 15.5 g/t gold, 191g/t silver, 10.8% copper, and 4.7% Zn. Drilling in January/February 2006 confirmed the presence of this high grade system, with sulphide intersections up to 19m below the sea floor, with a best intersection of 11.6m at 9.1 g/t Au and 13.1% Cu.

By Justin C. I. Baulch, Robina Sharpe, Steven J. Downey, John P. Feenan, Kate M. Perrin

Since becoming a public company in October 2005, Neptune Minerals has continued to advance its primary aims. Major achievements in the last year have been: • Successful completion of two simultaneous New Zealand exploration programs, Kermadec 2007 (K-07) and Colville-Monowai 2007 (CM-07); • New discovery of an inactive SMS field on the Rumble II West seamount; • Focused exploration license applications over quality areas of known SMS mineralization in arc and back-arc settings in Japan, Vanuatu, Papua New Guinea (PNG), Northern Marianas Islands (CNMI), Palau, and Italy; • Granting of licenses covering some 200,326 km2 of arc and back-arc within the EEZ of PNG and the Federated States of Micronesia (FSM); • Targeting of an additional mineralization style with extensive applications in PNG covering Conical Seamount-style Au-rich epithermal mineralization; • Welcoming Newmont Mining, one of the World’s largest mining companies, as a major shareholder; • Commissioning a scoping study to investigate options for mining and processing of SMS; Marine Minerals of the Pacific: Science, Economics and the Environment UMI2007 · The University of Tokyo, Japan Baulch 2 37th Underwater Mining Institute · 15-20 October 2007 • Invitation to contribute to, and participate in, the Meteor M73/2 Tyrrhenian Sea research program. The Company has granted exploration licenses covering 263,000 km2 in New Zealand, FSM and PNG, and a further 362,000 km2 under application in Japan, PNG, Vanuatu, Northern Mariana Islands, Palau and Italy.

By Russell Parrott

Acoustic techniques offer a rapid, economical, non-intrusive method of obtaining information about the stratigraphy and properties of seafloor sediments. During the past decade there has been a dramatic increase in the level of sophistication of high resolution seismic reflection equipment used for seabed and subsurface studies and in the signal processing techniques applied to the data collected with these systems. Processing of data from acoustic sources with repeatable and calibrated output, allows quantitative measures of the reflection coefficient, acoustic attenuation and scattering parameters of the sediments on the seafloor. Graphic recordings of seismic reflection data emphasize the coherent portion of the reflected energy for qualitative estimate of sediment properties and subsurface stratigraphy. Through application of signal processing techniques, quantitative information can be extracted from the coherent and incoherent components of seismic reflection data for estimation of surface character and sediment properties. These calculated parameters can be applied through interpolation between areas of available groundtruth. Acoustic techniques are used extensively to establish the regional geological framework of project areas and can also be used to extrapolate available groundtruth data into previously unsampled areas, and to optimize the design of a sampling program to provide the necessary groundtruth for the survey area.

Jan 1, 1985

By Peter A. Rona

Hydrothermal mineralization along slow-spreading oceanic ridges and rift -zones that comprise more than half the global length of the seafloor spreading center system is related to anomalous physical and chemical conditions acting within the geologic settings that characterize early and advanced stages of opening of an ocean basin. Mineralization in the early stage of opening is represented by the Atlantis II Deep of the Red Sea. There, hypersaline hydrothermal solutions discharging as density stratified brines into an axial basin, have formed the largest massive sulfide deposit (70 x 106 metric tons) known at a spreading center. Mineralization at the advanced stage of opening is represented by two types of sites: (1) oceanic crust on the wall of a rift valley; and (2) oceanic crust exposed on the wall of a transform fault zone. The first type of site is the TAG Hydrothermal Field, located on a wall of the rift valley of the Mid-Atlantic Ridge at the top of the basaltic layer of oceanic crust. Evidence is presented for multi-stage, high- and low-temperature hydrothermal activity that produces Cu, Fe, and Zn enrichments within the thin sediment column and stratiform interlayered deposits of manganese oxides, iron oxides, hydroxides and silicates, on the seafloor. The second type of site occurs along walls of transform fault zones of the equatorial Mid-Atlantic Ridge and Carlsberg Ridge, which exhibit stockwork-type Cu-Fe sulfide mineralization

Jan 1, 1985

By D. S. Cronan

Based on analogy with the Clarion-Clipperton zone, three main factors appear to influence the occurrence of potentially economic nodules in the study area, (i) elevated biological productivity, mainly above 50gCm-2y-l, (ii.) sea floor depth near or below the CCD, (iii) an absence of turbidite sedimentation. These conditions are fulfilled in parts of the following basins, where available data indicate that high grade and sometimes abundant nodules occur. i) The East Central Pacific Basin west of the Line Islands extending to the East Central Pacific Basin north and east of the Phoenix Islands ii) The West Central Pacific Basin west and northwest of the Phoenix Islands iii) The North Penrhyn Basin north of Penrhyn Island Notwithstanding the similarities between the environmental conditions under which potentially economic nodules occur in the Clarion-Clipperton zone and in the areas listed above, such similarities may relate only to present day conditions. During the possibly long periods of nodule formation, environmental conditions may have varied, and the deposits formed under conditions different from those prevailing at the present day. However, the fact that both present day conditions and the deposits in the two areas do show similarities suggests that applying the same genetic model to them has some validity. Possibly, any changes in environmental conditions during the period of formation of the deposits has been similar in both areas. Such uncertainties can only be resolved by a much fuller evaluation of the evolution of nodule deposits in both areas throughout recent geological time.

Jan 1, 1986

By Charles L. Morgan

In a commercial effort to characterize deep seabed manganese deposits in the Clarion-Clipperton region of the northeastern tropical Pacific, Ocean Mineral s Company carried out 16 expeditions to the region between -1978 and 1981. During these cruises OMCO collected substantial data. Activities included acoustic profiling, video and photographic imaging of the seabed, and sampling of the deposits with dredges, box cores and free-fall grab samplers. In 1990 the samples, photographs, technical reports and computer data bases which resulted from this work were archived at the Marine Minerals Technology Center at the University of Hawaii. This preliminary examination of the collection focuses on the biological observations made from almost 10,000 photographs of the seabed and the manganese nodule size distributions and compositional data from the free-fall grab recoveries. Regional trends are evident in all three data types. The biological examinations of the seabed photographs show significant geographical trends, with greater abundances of organisms being noted in the northeastern extreme of the region, decreasing toward the southwest (11.4 to 2.7 observations per 100 m2; 460 to 190 g per 100 m2). The nodule size distributions suggest that the ratio of the nodule burial rates to growth rates systematically decreases over the same range (0.65 to 0.36 nodules buried per 1 cm of growth). Preliminary geostatistical analysis of the ore grade data show that, in addition to high local variability, some deposit

Jan 1, 1991

By John Noakes

Marine scientists at the University of Georgia, have in the past few years, designed, developed and refined two geochemical survelliance systems for the exploration of hard mineral resources on the seafloor. The one first developed is an underwater sled which contains a nuclear radiation detector for measuring naturally occurring gamma radiation that is associated either with marine phosphorites containing uranium and its decay daughters or thorium decay products that are indicative of monzanite. The latter can, in most instances, be used as a pathfinder mineral for placer deposits that may contain other heavy minerals of interest such as rutile, ilmenite, chromite, gold, etc. This sled is operational in continental shelf depths. The second system is capable of more definitive measurements in the form of direct elemental analyses of the silt and clay fractions within the surficial sediments. It consists of a towed sled containing a submersible pump which, upon agitating the sediments, transfers the finer fraction up a hose to a shipboard centrifugal cone then to an automated sample processor. The resultant samples are rendered into sediment wafers, suitable for non-destructive XRF analysis. The system is capable of shipboard analysis for specific elements within minutes after sampling, allowing a cursory look upon which an exploration grid can be formulated while on site. A much wider spectrum of up to 40 elements can be evaluated when the wafers are returned to the land based laboratory.

Jan 1, 2011

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 Allan Spencer

In March 2007, Nautilus Minerals Inc. announced that they had commenced their 2007 exploration and development program with the mobilization of the Research Vessel Wave Mercury and the Survey Vessel Aquila onsite Papua New Guinea.

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 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 Tetsuo Yamazaki

Deep-sea rare-earth element-rich mud (REE Mud) distributes in pelagic clayey sediment column on ocean seafloor at 4,000-6,000 m deep. The thickness ranges 5-80 m and the burial depth 0-100 m. The REE content ranges 600-2,250 ppm in Pacific and one of the richest, maximum 6,500ppm, has been found in Marcus Is. exclusive economic zone. By applying a conventional hydraulic excavation and lifting methods, the economy of REE Mud mining around Marcus Is. is preliminary examined. Because the waste content in REE Mud is high and the disposal cost in Japan is very expensive, the mining is recognized far away from economy.

Sep 14, 2011

By Kokichi Iizasa

Modern Kuroko-type deposits have been much reported in submarine calderas and cauldrons in the EEZ of Japan since 1988. Some of them have been found based on heavy mineral analysis of sediments in which sulfide particles may be derived from hydrothermal sources in the ambient areas. From the end of August to early September 2007, in the middle Izu-Ogasawara arc south of Tokyo, ROV expeditions were carried out in submarine calderas in order to examine mineralogical features between intact heavy particles spouting out from sulfide chimneys and heavy minerals such as sulfides in sediments around sulfide mounds in Kuroko-type deposits, and to find more newly formed hydrothermal sulfide fields in those areas. Some preliminary results from the ROV expeditions are reported here.

Oct 15, 2007

By Nobuyuki Okamoto

Ferromanganese crusts on the seamounts in the Pacific Ocean are potential resources of cobalt, nickel, platinum and REEs. Particularly, those of the Republic of Marshall Islands and the Federated States of Micronesia (FSM) waters are believed to be of the highest resources potential area in the Pacific Ocean. The total six cruises using the Japanese Research Vessel Hakurei Maru No. 2 were carried out in the seamounts of the Marshall Islands in 1996, 1998 and 2002, and of the FSM in the 1997, 1998 and 2005 for evaluation of economic potential for cobalt-rich ferromanganese crusts as part of the Japan-SOPAC joint project. During these cruises numerous data such as bathymetric, geological, geophysical and environmental data were obtained. Geophysical exploration with backscatter mapping and side scan sonar, visual imaging using towed TV camera and geological sampling using dredge bucket and/or benthic multi-coring system (BMS) were conducted on these seamounts. In this presentation, we will report the mode of distribution of the crusts and calculated resource estimation based on the results of these geological and geophysical shipboard survey and land-based analyses. Keywords: ferromanganese crusts, Marshall Islands, Micronesia, resource potential

Jan 1, 2011

By Ian B. Corbett

De Beers Marine Pty Ltd. (South Africa) (DEBMARINE), a wholly owned subsidiary of De Beers Consolidated Mines Ltd. specializes in the provision of contracting and consulting services for offshore diamond exploration, Mineral Resource Management and mining. Established in 1983, the company is strongly focused on driving and sustaining growth of the offshore diamond mining industry into the 21st century. DEBMARINE provides full Mineral Resource Management and produce almost half a million carats annually for the Namibian Diamond Corporation (Pty) Ltd. from their offshore mining licence. The company is also extensively involved in feasibility studies to establish new mining ventures and in the exploration of several offshore Prospecting Licence Areas for other clients. As a pioneer in this field, DEBMARINE remains highly focused on technological development. A specialized section, the Technical Development Business Unit, has been established. Through relationships with various technology leaders, this unit develops new sub-sea mining technology and delivers productivity innovations aimed at realizing maximized carat extraction. This talk provides a broad perspective on the development of the Namibian offshore deposits and examines the critical role played by high-resolution orebody characterization and high-confidence Mineral Resource development at De Beers Marine.

Jan 1, 1998