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By Henk van Muijen

From an interesting and intriguing scientific research topic, deep sea mining has altered into an interesting mining prospect over the last years. Ten years ago most of the focus was on geological investigations, searching for typical deep sea deposits and getting answers on where we can find them and how these deposits were formed. At this moment we know much more about the interesting deposit possibilities and with our quest for minerals, metals and other materials to feed global economic growth, answers as to the technical and economic feasibility to mine these deposits are sought. This is not a new phenomenon as we already witnessed such question late 1970?s and early 1980?s. Most of the focus was on mining manganese nodules and brines in the Red Sea driven by the report of the Club of Rome that predicted shortages in near future at that time. Development went different, but later in the 1990?s a rival of interest could be noticed for mining deep sea deposits.

Jan 1, 2010

By Akira Usui

The small-scale observations, mapping, sampling, and in-situ experiments have been carried out since 2009 using JAMSTEC ROVs at some model seamounts in the Northwestern Pacific seamounts. Laboratory analysis on mineralogy, chemistry, chronology indicated a continuous slow precipitation since the Middle Miocene, at water-depths 1-6 km, and the modern hydrogenetic precipitation even in the oxygen minimum zones. Thus the variability in abundance and grade of the deposits on regional, small and microscopic scales are determined by geological, geochemical, and hydrological conditions, resulting in the stacked piles of tiny precipitates from the seawaters.

Jan 1, 2018

By Paulo Chaves, Márcia Gonçalves, João R. S. Carvalho, Fernando J. A. S. Barriga, Edgar Carrolo, Tiago Luna, Ricardo Rato, Anabela Bento

INTRODUCTION For the last decades, deep-sea marine resources such as seabed massive sulfides (SMS), polymetallic nodules and ferromanganese crusts (Fe-Mn crusts) have received an ever- increasing amount of attention worldwide for their abundance in critical metals and potential commercial value. This interest has mostly been driven by the growing world demand for raw materials, in particular for high- and green-technology applications (e.g., hybrid and electric cars, batteries, photovoltaic solar cells, cell phones, super magnets), as well as by industrialized countries governments other than BRICS states need to secure a more diversified supply of metals, resulting in a new deep ocean exploration boom. Since the oceans and its resources are increasingly seen as indispensable for humans needs and their challenges in the decades to come, this boom increments pressure on marine areas, either in international or within countries economic exclusive zone (EEZ). Since 2002, the International Seabed Authority (ISA) has signed up 29 contracts with several entities and national governments from multiple countries (e.g., Japan, China, Germany, France, Russia, India, Rep. of Korea, UK, Canada, Brazil) for exploration for deep-sea mineral resources in international waters, either for scientific or commercial proposes, which together cover over 1.3 million km2 [1]. In turn, over 300 exploration licenses, covering more than 650,000 km2, have been granted within the EEZ of Pacific countries such as Papua New Guinea, Tonga, Fiji, Solomon Islands and Vanuatu [2, 3]. This number is expected to increase very rapidly, as 77 countries have proposed to the United Nations the extension of their continental shelf in order to extend their EEZ and jurisdiction over potential deep-sea mineral resources [4]. Its estimated that 42% of the potential areas for SMS occurrences, 54% for cobalt-rich Fe-Mn crusts, and 19% for polymetallic nodules lie within the EEZ of coastal countries [5]. In addition, a huge amount of seafloor is yet to be explored and evaluated. Combined, the size of the granted exploration areas represents less than 10% of the overall area thought as most favorable for the occurrence of the 3 types of deep-sea mineral resources above mentioned. This means that today’s assessments on deep-sea mineral resources are only a rough approximation.

Jan 1, 2018

By M. E. Williamson

In September 2005 Williamson & Associates, Inc. delivered the BMS2 remotely operated seafloor coring system to the Japan Oil, Gas & Minerals National Corporation (JOGMEC). During acceptance trials aboard the JOGMEC research vessel R/V Hakurei Maru No. 2 the BMS2 successfully recovered 7.44 m of rock core in 3377 m water at a site near the crest of a seamount about 500 nm SE of Japan. Hydrogenous ferromanganese oxide crust, basaltic lava, sandstone and volcanic sediments were sampled with near 100% core recovery. The BMS uses rotary rod coring tools to collect samples to a maximum depth of 30 m in water depths up to 6000 m. Depending on bottom type to be sampled, the BMS tool magazine can be loaded with various drilling tools including core barrels with different bit types, drill rod and bore hole casing. The drill has 9 video cameras, a suite of sensors and 60 hydraulic functions powering thrusters, telescoping legs, seawater pumps and all of the standard drilling controls. The BMS provides deep water investigations with the functionality of conventional diamond bit rod drilling currently the mainstay of exploration programs in land mining.

Jan 1, 2005

By Mayumy Amparo Cabrera-Ramírez

Polymetallic nodules are a widespread resource in the Pacific Ocean, particularly in the areas of Clarion-Clipperton (Cronan, 2000). The most abundant mineral phases are forme d by iron and manganese oxides, with minor elements such as nickel, copper, cobalt, molybdenum and rare earths elements (Cronan, 1977; Cronan and Moorby, 1981; Iyer and Sharma, 1990; Mangini et al. 1990; Banerjee et al. 1991). In the Clarion-Clipperton Zone (CCZ), several authors mention that there are three main mineral species of manganese oxides, which have been recognized and which are associated with different processes of formation: todorokita (Mn2+, Ca, Mg) Mn3 4+ O7. H2), vernadite dMnO and birnessite enriched in Fe and (Na, Ca) 0.5 (Mn4+, Mn3+) 2O4. 1.5 H2O. In nodules of hydrothermal origin have been found todorokite, birnessite, vernadite, goethite and pyrolusite. Although there are many oxides and hydroxides of manganese and iron in amorphous and microcrystalline phases that make up the bulk of the nodule (Frondel et al. 1960; Cronan 1977; Dymond 1981; Calvert and Piper, 1984; Aplin and Cronan, 1985; Martin and Lallier, 1993; Achurra et al. 2009), identifying specific mineral phases is difficult due to the intergrowth of different phases and associated detrital material.

Sep 14, 2011

By Dennis Sánchez Mora, John Jamieson

INTRODUCTION Work by Humphris et al., (2002); Ondréas et al., (2009); Barreyre et al., (2012); and Escartín et al., (2015) has identified active and inactive hydrothermal sites along the Lucky Strike segment. The sites that contain the largest accumulation of known sulfides are located between the north and the southern zones (Figure 1), a vent site area that is referred to as the Main Lucky Strike hydrothermal field (Escartín et al., 2015). Hydrothermal fluid outflow has been linked to a shallow fault network (Barreyre et al., 2012). However, specific constraints on fault geometries have not been determined. Other off-axis sites at Lucky Strike, such as Capelinhos (high temperature vent), and Grunnus (inactive?), as well as a low temperature vent field (on-axis), Ewan, have been described by (Escartín et al., 2015). Given the spatial relationship between the Main Lucky Strike hydrothermal field (MLSHF), and the intersection of northern rift faults with the southern rift faults, a structural analysis of this area can provide insight into the fault controls on fluid flow that leads to hydrothermal venting and sulfide precipitation. METHODOLOGY Structural data (dip direction and dip) was determined using Leapfrog Geo 4.0 software. Bathymetric data was obtained from Escartín et al., (2015) and references therein. The bathymetry was imported into Leapfrog Geo (in UTM format) and, using the structural modelling tool, individual measurements with dip direction and dip data were collected with a focus on the northern volcanic rift and the southern central volcano (Figure 2a). All measurements were taken from what the authors consider as normal faults, and to aid the determination of individual measurements a “face dip” map was constructed, where the bathymetry is colored by slope angle (Figure 2b). All measurements are simultaneously plotted on a stereonet generated by the Leapfrog Geo Software. Data were divided into northern and southern, and western and eastern zones to determine the relationship between hydrothermal venting and the structural geometries at Lucky Strike (Figure 2c). Slip measurements for individual faults were determined along the dip of the fault with a measuring tool. Net slip, heave (horizontal displacement), and throw (vertical displacement) was calculated for each of the zones.

Jan 1, 2018

By Amy Gartman

"Seafloor hydrothermal systems result in the emission of abundant particles and nanoparticles into seawater1. Many of the elements in these particles settle locally, although some are transported distally to the global ocean2. Although broad similarities exist, the mineralogy, size and therefore reactivity of particles emitted varies between sites in the global ocean, and even within sites at the same vent field. The particle geochemistry of these vent fields is a critical but little understood component both from a perspective of baseline characterization and potential environmental impacts.The mining of seafloor massive sulfides formed from hydrothermal venting will generate a new class of particulates in the deep ocean. Broadly, black smoke and SMS tailings exhibit similarities including abundant Cu, Fe and Zn sulfides, and a large number of submicron particles. In addition to the major minerals, minor minerals including As, Bi, and Pb are present, especially in back arc settings. However despite broad similarities, natural “black smoke” and crushed sulfides created during mining operations differ significantly in size class, morphology, abundance, and reactivity. A comparison of these two classes of particulates will be presented, including chemical composition and reactivity to dissolution and oxidation."

Jan 1, 2017

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 R/V Ka’imikai-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, including metal-rich plumes and helium anomalies. Only two of the volcanoes, namely Brothers and Clark, showed chimneys and surficial polymetallic sulfide deposition. Hydrothermal venting at a water depth of approximately 1,650 meters near the base of the northwest caldera wall of Brothers volcano has produced a field of chimneys, some of them seven metres high and discharging black smoker venting. Temperatures up to 300°C were measured from the active vents. Clark volcano has a double cone summit at a water depth of 875 meters. The shallowest cone has a near-summit hydrothermal vent field with five-meter tall venting chimneys with smaller structures around the periphery.

Aug 24, 2006

By Karsten Hagenah, Tor Jensen, Jens Laugesen, Øyvind Fjukmoen, Lucy Brooks

This paper describes operational environmental threshold levels for exploitation of mineral resources in the deep sea. Such criteria are needed to be able to monitor and control deep sea mining with respect to the stringent environmental requirements that are needed. It is recommended to use existing environmental threshold levels for comparable activities where such are existing. Fields of application are mainly but not exclusively seabed mining operation activities under the governance of the International Seabed Authority (ISA). The threshold levels and limits mentioned in this paper are proposed recommendations based on other activities than seabed mining but are a proven and accepted approach in other maritime industry activities. An example of such other activities with proven and accepted environmental threshold levels are Oil & Gas exploitation activities in the sea. Background The first exploitation of mineral resources is coming closer. At the moment regulations for exploitation for mineral resources in the Area are being developed by the International Seabed Authority (ISA). The ISA regulations will contain the framework related to environmental monitoring of exploitation. However, the regulations will not contain operational environmental threshold levels for the Contractor.

Jan 1, 2018

By Karsten Hagenah, Tor Jensen, Jens Laugesen, Øyvind Fjukmoen, Lucy Brooks

This paper discusses operational environmental threshold levels for exploitation of mineral resources in the deep sea. Such criteria are needed to be able to monitor and control deep sea mining with respect to the stringent environmental requirements that are needed. It is recommended to use existing environmental threshold levels for comparable underwater activities. Fields of application are mainly but not exclusively seabed mining operation activities under the governance of the International Seabed Authority (ISA). The threshold levels and limits mentioned in this paper are proposed recommendations based on other activities than seabed mining but are a proven and accepted approach in other maritime industry activities. An example of such other activities with proven and accepted environmental threshold levels are Oil & Gas exploitation activities in the sea. Background The first exploitation of mineral resources in international waters is coming closer. Presently regulations for exploitation for mineral resources in the Area are being developed by the International Seabed Authority (ISA). The ISA regulations will contain the framework related to environmental monitoring of exploitation. However, the regulations will not contain operational environmental threshold levels for the Contractor.

Jan 1, 2018

By Cornel E. J. de Ronde

Volcanic arcs, including both island arc and intra-oceanic arc systems, combined extend for ~22,000 km around the Earth, with the majority (~20,000 km) occurring in the Pacific basin. These arcs are host to over 700 volcanoes of which ~200 are submarine and as such represent great potential for hosting massive sulfide deposits formed at seafloor hydrothermal vent sites. The Kermadec arc extends for ~1,200 km northeastwards from the North Island of New Zealand and forms the southern part of the ~2,500-km-long Tonga-Kermadec intra-oceanic arc system. At least 94 volcanoes are known to exist along this system with 74, or about 80%, being submarine. At least 33 volcanoes occur along the Kermadec part of the arc with all but one (Raoul Island) being submarine. The first sulphides recovered from the entire Tonga-Kermadec arc were in 1996 from the Brothers and Rumble II West volcanoes of the southern Kermadec arc. The 1998 R/V Sonne research cruise recovered a more comprehensive suite of mineralised samples from Brothers, and also found evidence for hydrothermal venting at Monowai, Vulkanolog, Rumble III and Clark volcanoes. The March 1999 NZAPLUME cruise systematically surveyed 260 km of the southern Kermadec arc and found that 7 of 13 volcanoes were hydrothermally active, with the vent fields either located within calderas (e.g., Brothers, Healy, Rumble II West) or atop volcanic cones (e.g., Clark, Tangaroa, Rumble V, Rumble III). The May 2002 NZAPLUME II cruise surveyed a further ~580 km of the mid-segment of the Kermadec arc, from Brothers to volcano 'L', a submarine volcanic edifice 35 km NW of Macauley Island. This cruise surveyed 13 major volcanoes and 8 smaller volcanic edifices and confirmed hydrothermal venting at the Vulkanolog site, and discovered new vent fields atop a volcanic cone within Macauley caldera, immediately offshore Macauley Island, and another at the summit of volcano 'L'. A further new site was found atop a volcanic knoll immediately S of Healy caldera during time-series sampling of the vent sites found during the 1999 cruise. All the vent sites discovered along the Kermadec arc occur in water depths between 1650 and 150 m.

Jan 1, 2002

By Jan M. Peter

The Early Norian Windy Craggy massive sulfide deposit is within the allochthonous Alexander terrane of the Insular tectonic belt in extreme northwestern British Columbia (Figure 1). Host rocks are the Middle Tats Volcanics, part of an informally-named volcano-sedimentary succession of mixed graphitic argillites and mafic pillowed and massive volcanic flows and sills of Upper Triassic age (Figure 2) that have suffered only lower greeschist-facies metamorphism. The volcanic rocks are light rare earth element (LREE)-enriched and display a variably developed back-arc subduction signature. Major and trace element compositions of the host argillite show that it contains an appreciable hydrothermal component, as evidenced by low high Fe and Mn contents. These sediments therefore record steady, continuous hydrothermal activity punctuated by intermittent turbidity currents sweeping into the basin. The deposit consists of at least two discrete sulfide lenses (the North and South Sulfide Bodies), as shown in Figure 3, a level plan at the elevation of the exploration workings. Published reserves at 0.5% copper cut-off are 297.4 million tonnes grading 1.38% Cu, 0.08% Co, 0.21 g/t Au and 3.9 g/t Ag (as of December 1991). However, the deposit is larger than this and further drilling is required to delineate it completely. Mineralization comprises massive sulfide, stringer/stockwork, and finely bedded to laminated sulfides and exhalites. Stockwork mineralization consists of sulfide-quartz-chlorite veins with attendant chlorite and silica alteration. Mineralization consists predominantly of massive pyrrhotite andlor pyrite with lesser chalcopyrite and magnetite. Figure 4 is an oblique section through the North Sulfide Body, the most northerly sulfide mass shown in Figure 3, which shows the distribution of the pyrite and pynhotite-rich massive mineralization and the stringer zone. The North Sulfide Body contains appreciable sphalerite, whereas the South Sulfide Body contains only trace amounts. Gangue minerals include quartz, chlorite, calcite, siderite, ankerite, stilpnomelane and magnetite. The minor hydrothermal exhalite sediments are comprised of chert, carbonate, and minor

Jan 1, 1993

By Raymond A. Binns

In this first sub-seafloor examination of an active hydrothermal system hosted by felsic volcanic rocks at a convergent plate margin, we drilled 13 holes altogether, achieving deep cored penetrations at two sites. Our aims were (1) to delineate the lateral and vertical variability in mineralisation and alteration patterns below the PACMANUS hydrothermal site near the 1650-1700 m-deep crest of Pual Ridge in the eastern Manus back-arc basin, so as to understand links between volcanological, structural and hydrothermal phenomena, and (2) to establish the nature and extent of microbial activity within the system. Technological innovations vital to success included our precise location of holes on small targets with drill-stem video, the use of a new hard-rock re-entry strategy, and deployment of casing with a new hammer drill. Other technical achievements were the first ODP application of an advanced diamond coring system, and the first direct comparison in a hardrock environment between structural images obtained by wireline methods and by logging-while-drilling (resistivity-at-bit).

Jan 1, 2002

By Andrea Koschinsky

Numerous hydrothermal vents occur along the Earth?s oceanic spreading axes documenting the reaction of seawater with hot magmatic rocks. The circulation of seawater through the oceanic crust, the interaction with hot rocks in the crust, and the subsequent discharge of hot metal- and gas-rich fluids into the ocean have significant implications for the cycling of material and energy on Earth. Until recently, hydrothermal activity was unknown from the Mid-Atlantic Ridge (MAR) south of the Equator where the MAR is offset by about 1000 km at the St. Paul?s and Romanche fracture zones. During a British cruise in February/March 2005, the first active hydrothermal vent field was discovered on the southern MAR at 5°S. During our follow-up cruise M64/1 in April 2005, the first samples from this vent field were recovered with the ROV QUEST (Univ. Bremen) and analyzed onboard. The high-temperature vent field is situated in a water depth of 2990 m along a line of collapse pits within a large basaltic sheet flow. A diffuse, low-temperature field occurs in a jumbled sheet flow few hundred meters to the east with warm water streaming out of cavities between lava blocks. Here we show for the first time that boiling fluids of ~400°C are emanating from sulfide-bearing vents at a depth of about 3000 m at a slow-spreading Mid-Atlantic Ridge segment. Although this segment is composed of thick basaltic crust, these fluids are dominated by hydrogen relative to methane. Whereas the active chimneys consist of pyrrhotite, chalcopyrite, and isocubanite, the mineral association hematite-magnetite-pyrite occurs in the inactive chimneys suggesting that the fluids became more reducing in present times. The high hydrogen contents and the high temperature of the fluids as well as the change to more reducing conditions are most likely related to a young volcanic eruption event some 300 m east of the hydrothermal field. The presence of hematite and magnetite may indicate that the upflow zone or even the reaction zone at 5°S used to be more oxidized then at other MOR sites, where the hydrothermal fluids are commonly buffered by the pyrite-pyrrhotite-magnetite (PPM) buffer. Consequently, high iron contents and high hydrogen/methane ratios occur in high temperature fluids from basaltic host rocks rather than being restricted to ultramafic host rocks. Faunal communities at the South Atlantic vents largely resemble those from the North Atlantic vents implying that the large Equatorial fracture zones do not inhibit or obstruct faunal exchange along the Mid-Atlantic Ridge.

Jan 1, 2005

By Yves Fouquet

Recent exploration demonstrates that hydrothermal systems related to upper mantle ultramafic outcrops are common in the modern ocean. Most sites are located on slow spreading ridges with a low magmatic budget. Volcanogenic Massive Sulfide (VMS) deposits, associated with basalt, along the Mid Atlantic Ridge (MAR) are volcanically controlled near the topographic highs at the center of the segments. Three preferential settings are identified for ultramafic sulfide mineralization: 1) Off axis, on rift valley walls, near the amagmatic ends of the segments; 2) Non-transform offsets and 3) Ultramafic dome structures at the ridge transform fault intersection. The upper surface of these domes is often interpreted as a detachment fault. Three processes are considered for driving hydrothermal cells in ultramafic rocks: 1) regional heat flow at the ridge axis 2) Cooling of a deep gabbroic intrusion and 3) exothermic heat produced during serpentinisation. Along the Mid Atlantic Ridge, four types of ultramafic hydrothermal mineralization are observed: 1) High temperature (>350°C) sulfide mineralization related to low pH fluids, (ex. The Logachev field at 14°45? N and the Rainbow field at 36°14 N); 2) Medium temperature carbonate chimneys (<100°C) related to high pH fluids (ex. The Lost City site at 30°N); 3) Low temperature diffuse venting associated with extremely high methane discharge and pervasive alteration and silicification of both volcanic and ultramafic rocks (ex : The Saldanha field at 36°34 N); 4) Stockwork mineralization and quartz veins with sulfides related to gabbroic intrusions within ultramafic rocks (15°N). When compared to mineralization in a basaltic environment, sulfide deposits are enriched in copper, zinc and specific elements related to an ultramafic rock source such as Ni and Co. They are also significantly enriched in gold which, unlike in basaltic environments, has a bimodal occurrence both in low temperature Zn-rich assemblages and in high temperature Cu-rich mineral assemblages. The Cu-Zn-Co-Au deposits along the Mid Atlantic Ridge seem to be more common than on land where few similar VMS deposits are known. We consider that ultramafic VMS deposits on slow spreading ridges constitute a specific marine type of mineralization that is less easily than back arc deposits, incorporated into the continent during obduction processes.

Jan 1, 2004

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 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 Eric J. Foell

The Offshore Technology Conference (OTC) was founded in 1969 when a group of scientific and technical societies organized an annual conference and exhibition dedicated to technologies used in the offshore oil, gas and mining industries. Currently, OTC is sponsored by 12 industry organizations and societies. These include: American Association of Petroleum Geologists (AAPG); American Institute of Chemical Engineers (AIChE); American Institute of Mining, Metallurgical, and Petroleum Engineers (AIME); American Society of Civil Engineers (ASCE); ASME International Petroleum Technology Institute; Institute of Electrical and Electronics Engineers/Oceanic Society (IEEE-OES); Marine Technology Society (MTS); Society of Exploration Geophysicists (SEG); Society for Mining, Metallurgy, and Exploration (SME); Society of Naval Architects and Marine Engineers (SNAME); Society of Petroleum Engineers (SPE); and The Minerals, Metals, and Materials Society (TMS). OTC also has two endorsing organizations, the International Association of Drilling Contractors (IADC) and the Petroleum Equipment Suppliers Association (PESA), as well as 6 supporting organizations that include the American Petroleum Institute (API), the Independent Petroleum Association of America (IPAA), the Institute of Marine Engineering, Science, and Technology (IMEST), the International Association of Geophysical Contractors (IAGC), the National Ocean Industries Association (NOIA), and the United Kingdom Offshore Operators Association (UKOOA). From its earliest years, the OTC has been held during the first week of May in Houston, TX, initially at the Albert Thomas Convention Center where OTC?69 drew 4200 attendees and 200 exhibitors. As the conference grew and became established as the world?s foremost event for the development of offshore resources in the fields of drilling, exploration, production, and environmental protection, the venue was changed to the Astrodomain Complex, with technical paper sessions and most exhibits taking place in the Astro Hall. The numbers of attendees and exhibitors varied somewhat over the years, primarily in accordance with the fortunes of the international oil and gas industry. At its height in the early 1980s, OTC registered attendance exceeded 100,000 with more than 2500 exhibitors forcing expansion into the Astro Arena and even the Astrodome.

Jan 1, 2005

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

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

Oct 15, 2007