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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

By John Parianos

2013 has seen good progress for Nautilus Minerals and our projects due to the determination of our people and the continued support from shareholders and stakeholders. Our focus remains Solwara 1 in Papua New Guinea for which the build continues on the seafloor production tools, subsea slurry pump and riser and lifting system.

Sep 14, 2011

By Yuta Yamamoto

Seafloor massive sulfides (SMS) which contain Au, Ag, Cu, Zn, and Pb have been interested in as a target of commercial mining these 15 years. Japan has large potential of SMS and a national R&D project for the mining has been active these 5 years. However, the economy of SMS mining is very bad, because the waste tailing disposal cost is very expensive in Japan. A slurry flushing method is experimentally examined in this study for the improvement of the economy. During the flushing, because of density difference between the metal-rich ore and the waste rock, a kind of gravity separation is possible. The results suggest a possibility of the actual application.

Sep 14, 2011

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 Alexander Malahoff

Six active Kermadec Arc submarine volcanoes located between 34°S and 36°30?S were mapped and sampled by an interdisciplinary inter-institutional research team between April and July 2005 using submersibles Pisces V and Pisces IV aboard the mother ship the RV Kai?mikai-O-Kanaloa. The purpose of the expedition was to study the relationship between hydrothermal activity, formation of hydrothermal mineral deposits and the biodiversity of life associated with the hydrothermal vents. Of the volcanoes examined, all showed evidence of hydrothermal activity, plume production and helium anomalies. Only two of the volcanoes, namely Brothers and Clark, showed chimneys and surficial poly-metallic sulphide deposition. Hydrothermal venting at a water depth of 1700 meters within the base of the northern wall of the summit caldera of Brothers Volcano has produced a field of chimneys, some of them 5 metres high with black smokers venting. Temperatures of 300°C were measured within the active vents. Clark Volcano has a double cone summit at a water depth of 875 metres. The shallowest cone has a near-summit hydrothermal vent field with 5-meter high venting chimneys and smaller structures around the periphery. Water temperatures of 200°C. Geochemical and petrological analysis of the massive poly-metallic sulphide samples taken from Brothers and Clark show a diversity of mineralogy. This diversity is clearly a function of hydrothermal water temperature. Chimneys sampled from Brothers are pyrite and sphalerite dominant with lesser chalcopyrite. Sulphides from Clark Volcano tend to be barite rich with lesser sphalerite and pyrite. Sulphides from Brothers Volcano have a range in gold composition of 4 to 58 ppb with silver composition of up to 38 ppb. A mineral formation model for the volcanoes suggests hydrothermal fluid boiling within the volcanic edifice for those volcanoes with shallow summits and massive sulphide deposition with the edifice as well. Surficial deposits include native sulphur and lower temperature oxides. Only the deeper water Brothers Volcano shows massive sulphide deposition along the marginal faults of the caldera floor.

Jan 1, 2005

By Mikhail D. Ageev

The paper concerns with some questions of Autonomous Underwater Vehicle (AUV) control system design, which allows a motion at rough undersea terrain. The AUV advantages reveal itself completely during exploration of such objects as seamounts and reefs area. These objects are characterized by steep slopes (30 degrees and above) and chaotic situated obstacles (rock debris, pinnacles, escarpments). Uses of other technical facilities for operating in such formations are difficult, dangerous or impossible. These regions take an interest due to the presence of iron-manganese crusts. Modern AUV can estimate density of mineral by means of still camera or video recorder. For this reason the vehicle has to move with the distance of 3-5 meters from seabed. Under such conditions micro- and mesorelief presents a considerable danger for AUV. The AUV can bypass underwater obstacles in the various ways. However, in any case AUV motion will be characterized by intensive maneuvering on various speed (from 0 up to 1.5 m/s), circular change of tractive force vector and, hence, a circular flow about the hull. So, AUV is equipped with the propulsion system, which provides free modes of motion. AUV control system (CS) has tri-level structure to allow a motion in a rugged seabed terrain. According to the generally accepted categorizations, CS includes execution, coordination and strategic levels. The strategic level contains the goals of AUV mission. Obstacles avoiding and route choice are realized by means of simultaneous maneuver in vertical and horizontal planes. Sonar system is used for data acquisition about obstacles. It consists of a few echo-sounders with fixed directivity pattern. The route choice algorithm operates at two lower levels of CS. Basic (?reflex?) functions of spatial motion are realized within the execution level and considered in the paper. The choice of motion modes is carried out at the coordination level of system. All accessible navigating information (the data from flight sensors and from multichannel echo-sounder systems) is used for this purpose. In addition the bypass of characteristic types of obstacles is carried out with the help of basic motion modes combination. The modeling results of bypass of various typical obstacles, and also their combinations are described in the paper.

Jan 1, 2011

By Georgy Cherkashov, Vladislav Kuznetsov

The presentation describes new data concerning the age of the Mid-Atlantic Ridge (MAR) hydrothermal fields. The collection of massive sulfides recovered from six hydrothermal fields has been dated using the 230Th/U method. The range of the data obtained is rather wide: from 2.2 up to 65.1 thousand years BP. Three stages of hydrothermal activity were detected for this 65 Kyr period of geological evolution: modern (0 -5), 20-25 and 58–65 thousand BP (Figure 1). This conclusion was confirmed by dating the associated metalliferous sediment layers which also indicate the hydrothermal events led to the formation of sulfide mineralization. There is a correlation between the age and size of massive sulfide deposits: older deposits are larger (Table 1). This and other applications of obtained data will be discussed in presentation.

Aug 24, 2006

By Karstein Vestgard

During the last few years autonomous underwater vehicle (AUV) technology has evolved from concept demonstrators towards commercial products. The driving forces are the move for energy exploitation towards deeper waters, naval applications and the Internet driven need for more intercontinental underwater communication cables. Other applications emerging for the future will be within environmental research and monitoring and deepwater exploration. Deepwater developments beyond the continental shelf will require the same level of survey data quality and intervention access as established for shallow water. The potential for cost savings is two folds. Firstly, there is a reduction in the survey cost it self and secondly there is a considerable cost saving by avoiding over design of subsea installations due to lack of sufficient documentation of the field. In this scenario, there is an increasing understanding that underwater robotics and in particular AUVs will play an important role in future survey and subsea engineering work. The AUV as a free swimming underwater survey sensor carrier has several advantages compared to cable controlled ROV?s and deep towed systems: The paper prepared for the ?Underwater Mining Institute 2003? on Jeju Island, Korea will focus on the HUGIN AUV concept and field results to date.

Jan 1, 2003

By Akira Usui

Fine-scale geochemical, mineralogical, and structural variations in ferromanganese crusts are believed to be the long-range records of paleoceanographic conditions and geological events on the small to global scales in the world oceans, which is useful in reconstructing marine environment. The chemical profiles of thick hydrogenetic ferromanganese crusts and nodules were determined by ICP/ES at 2-3 mm intervals at several locations over the Japanese Islands, Magellan Seamounts, Marshall Islands, and South Pacific Basins, together with Be-10 dating. We found general trend of Co enrichment (or high ratio of Co/Mn) in the upper layers of crusts, or outer layers of nodules, which formed in younger period probably after the late Miocene. This general trend of higher Co concentration in the surface may be true over the western to the Pacific, but local variations in growth patterns and shorter-range fluctuations in chemistry and structure were found as well. The growth rate is sometimes three times faster at the shallower depth even in a single seamount. The in-depth fluctuation of Co is well correlated with the ratios Mn/Fe ratio and Ce/La, suggesting changes in redox conditions during the growth of hydrogenetic ferromanganese crusts.

Jan 1, 2002

By Andrew Bellamy

A thorough appreciation of the origin, formation, preservation and geometry of marine sand and gravel deposits is central in demonstrating that their extraction by dredging does not affect coastal processes or marine life. Geological evaluation underpins wave, tidal and sediment transport modeling and assists in predicting the nature and extent of seabed change during and after dredging. Marine sand and gravel deposits in the English Channel, southern North Sea and parts of the Irish Sea are of predominantly periglacial fluvial origin and record long histories of valley and floodplain cut and fill associated with Quaternary climatic and sea level oscillations. In the Bristol Channel, the influence of marine transgression and tidal dominance in sorting proglacial outwash deposits is evident in the distribution of sandbanks, scoured channels and gravel lags of this region. These deposits are relict and are unrelated to coastal sediment dynamics. Their extraction leaves seabed depressions which monitoring shows remain unfilled. The resultant offshore bathymetric changes and sediment removal in over 10 m water depth are not transmitted to the coastal zone as beach drawdown, wave height increases or sediment starvation. Applications for new aggregate dredging permissions in UK waters must be accompanied by an EIA and need to make a convincing case that the dredging will not affect rare or declining species and communities of marine life. Seabed recovery rates post dredging are now investigated and understood with reference to geological setting and the uniqueness of the sediment/biological character (biotope). Investigation of the continental shelf by the Industry and others reveals the large extent of gravel-dominated biotopes relative to commercially viable deposits.

Jan 1, 2004

By S. Jeffress Williams

The topic area for this paper covers the United States portion of the northern Gulf of Mexico, extending from the Rio Grande delta east to the Florida peninsula. Declaration of an Exclusive Economic Zone in 1983 expanded Federal economic jurisdiction on the continental margins from 12 to 200 nautical miles seaward from the coast. The nation-wide area of the EEZ totals 3 million square nautical miles, with approximately 186 thousand square nautical miles in the Gulf of Mexico. In the Gulf, the continental shelf has an area of 81 thousand square nautical miles, extending to a depth of 600 ft. and having widths of 6 to 120 nautical miles. Specific areas on the shelf offer the greatest potential for containing aggregate and other hard mineral resources. The primary geomorphic features along the Gulf coast include: barrier islands, chenier plains, tidal inlets, bays and lagoons, estuaries, and deltaic headlands. These features are composed of terrigenous siliclastic sediments, except for the west Florida coast, south of 29°N latitude, which is dominated by carbonate sediments. On the shelf, the primary features are linear sand shoals and associated sand sheets, relict delta lobes and channels, and banks related to salt diapirs and coral reefs. The composition and distribution of sediments in these coastal and shelf features are determined by numerous geologic factors including: seabed topography; riverine sediment discharge; sediment dispersal patterns due to currents, waves, storms and tides; tectonics and subsidence; and repeated fluctuations in sea level.

Jan 1, 1986

By Seabed Mineral Authority Runanda Takere Moana

The Cook Islands is a group of 15 islands, being a Polynesian nation in the heart of the South Pacific Ocean and now bears the name of famed English navigator Captain James Cook, who sailed here in the 1770’s. In the 1800s, it was re-named “the Cook Islands” by illustrious Russian cartographers from the previous English name of “The Hervey Islands”. SEABED MINERALS The Cook Islands has one of the world’s most abundant deep seabed mineral (SBM) resources of Manganese nodules estimated at 10 billion tonnes, within its large Exclusive Economic Zone (EEZ) of almost 2 million square kilometres. This knowledge has been gained through numerous scientific surveys conducted in the Cook Islands waters by many international scientific research entities, starting with a Russian deep seabed marine survey in the 1970’s, from which many physical samples of these abundant Manganese nodules were first recovered. Some of the 1970’s Russian samples are still retained in the Cook Islands more than 40 years later. Then a comprehensive 21 year Pacific wide Seabed Minerals scientific study, between 1985- 2005, undertaken by the Japanese and SOPAC1 based in Fiji, confirmed that the Cook Islands has a vast, unique and valuable deep seabed minerals resource of Cobalt rich Manganese nodules. These Nodules contain many valuable minerals required by the global market including Nickel, Copper, Cobalt and Rare Earth Elements.

Jan 1, 2018

By Charles L. Morgan

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

Jan 1, 1989

By Arturo Carranza Edwards

One hundred ninety nine beach face sand samples from an equal number of beaches from the Mexican Pacific were studied. Based on petrological and chemical analysis some locations have been studied in more detail. Black sands from the following areas are discussed: (1) west Baja California Peninsula, where black sands rich in magnetite and ilmenite have maximum values of 50% iron and 14% titanium in the very fine sand fraction; (2) east Gulf of California, in its northern portion, the black sands show maximum values of 43% iron and 5% titanium in the fraction 2 to 4 0;-(3) the south Mexican Pacific, characterized mainly by medium sands, moderately well sorted, show that the fine sand fractions reach values of 35% iron and 41% titanium. X-ray fluorescence applied on selected samples constituted by feldsarenites and lithic feldsarenties, showed the presence of rare elements in some of the studied samples.

Jan 1, 1994

By Randolph A. Koski

Since 1985, numerous constructional sulfide-sulfate deposits in the form of mounds, pinnacles, chimneys, and sheets have been located between 40°45' and 41°05'N latitude in Escanaba Trough, the sediment-covered axial valley of the Southern Gorda Ridge. Single-channel seismic data indicate that three volcanic edifices up to 6 km in width penetrate as much as 500 m of turbidites that fill the valley; pillow and sheet flow lavas are exposed on the sea floor where these volcanoes breach the sediment surface. Observations from deeply towed camera systems and submersibles show that the largest hydrothermal deposits occur along the step-faulted northern flank of the central volcanic edifice and on the peripheries of steep-sided, sediment-capped hills, approximately 1 km wide and 100 m high, that rise above the valley floor. The sulfide deposits are highly oxidized, eroded, and partly buried by unconsolidated sediment; aprons of sulfide talus extend downslope from the mounds. Two types of sulfide have been sampled by dredging and submersible. The predominant mound and chimney material is pyrrhotite-rich massive sulfide with low amounts of Zn, Pb, Cd, and Ag. Coarse-grained zones with high porosity mark the location of myriad fluid channelways. Thin crusts of barite associated with pyrrhotite-rich sulfide have Au contents up to 2 ppm. Zoned fragments of polymetallic (Fe-Zn-Pb-Cu-As-Ag-Sb) sulfide dredged from a single site near 41°01'N latitude are part of a chimneylike vent structure with a

Jan 1, 1988

By Randolph A. Koski

Recent investigations located at least six major massive sulfide deposits (dimensions measured in tens to hundreds of meters) within a 50-km-long segment of Escanaba Trough, the sediment-covered axial valley of southern Gorda Ridge. The sediment fill is intercalated silt and sand turbidites and hemipelagic mud with a maximum thickness of 500 m. Several volcanic edifices, spaced at approximately 15-km intervals along the ridge axis, penetrate and locally breach the sediment. The largest sulfide deposits form mounds and ridges on the steep flanks of structurally unstable sediment-capped blocks that have been uplifted above the volcanic edifices; both sediment and sulfide deposits are undergoing rapid erosion and redeposition. Although hydrothermal activity appears to be absent at most sulfide fields, 220°C fluids are discharging from the tops of sulfide mounds near 41°00'N lat, 127°31'W long. Recent pillow lavas and sheetflows erupted onto the sediment-covered sea floor less than 500 m away from the active vent field. The massive sulfide deposits have compositional characteristics that differ from deposits formed on sediment-free spreading axes. The Escanaba Trough deposits include Fe- and Cu-rich, Zn- and Pb-poor massive sulfide mounds, polymetal (Zn-Fe-Pb-Cu-As-Ag-Sb-Sn) sulfide vent structures, abundant barite-rich chimneys, crusts, and sinter cones, and thermogenic petroleum in the sulfide and sediment. Sulfate-rich crusts have high Au values ranging between 2 and 10 ppm. The unusual mineral assemblage at Escanaba Trough

Jan 1, 1989

By Hans Smit

Start here.

Jan 1, 2018

By Sander van Leeuwen

Outline: · De Regt Marine Cables. · The link between system requirements and umbilical requirements (which system requirements have the largest impact on the umbilical design). · Design options for deep sea mining umbilicals (showing the various options for strength member constructions, power conductors and data-transmission). · Technical challenges and risks (outline on the most important technical challenges and risks involved in the construction, production and usage of deep sea umbilicals). · Umbilicals for the SWORD and Blue Nodules project.

Jan 1, 2018

By Odyssey Marine Exploration

Odyssey is a world leader in marine exploration and has undertaken expeditions in varying environments throughout the world addressing many commercial and regulatory demands. Odyssey works in a variety of settings such as shallow coastal territorial waters, abyssal plains in exclusive economic zones, and high seas in international waters on projects involving mineral exploration, environmental analysis, oceanographic survey, and recovery operations. Odyssey Marine Exploration (Odyssey) excels in adaptively managing programs from initial concept through realization of commercial goals while successfully satisfying the regulatory and engineering demands of deep sea projects. This poster presentation reveals best practices throughout a project life cycle and presents case studies in areas including but not limited to: • Research practices to identify and define valuable subsea resources • Project planning and licensing to achieve project goals and meet regulatory requirements • Optimizing offshore operations to achieve desired results • Designing projects to support processing and commercial programs

Jan 1, 2018

By M. E. Williamson

From December 2004 through March of 2005 an extensive geophysical program was conducted to delineate polymetallic sulfide deposits in the Bismark Sea for a major mining concern. Deeply towed sidescan sonar, interferometric swath bathymetry, subbottom profiling, magnetic gradiometry, electrical resistivity, induced polarization. self-potential, gravimetry, water temperature/conductivity and towed video were among the methodologies tested against known occurrences of polymetallic sulfides in 1500 m -- 2200 m water depths. Known active and currently inactive sulfide areas were characterized using the various remote sensing techniques followed by survey with these same tools in other areas where they successfully discovered new prospects. Dredge sampling was used to ground truth both previously known sulfide areas and newly found deposits.

Jan 1, 2005