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By Peter E. Halbach, Andreas Jahn

"Co-rich ferromanganese crust deposits exist on slopes, summits and platforms of seamounts and guyots throughout the global oceans, where deep-sea currents have kept the seafloor structures more or less free of sediment for millions of years. They form by direct precipitation from cold seawater under more or less oxic conditions and consist of thin layers (2 up to 25 cm thick) covering hard substrate rocks in water depths of 800 to 5000m (Halbach and Marbler, 2009; Hein et al., 2000). Besides Mn these crusts contain interesting concentrations of minor elements (Co, Ni, Ti and Cu) and trace elements (Mo, W, Te, Ga, Pt and REEs), thus they represent significant metal deposits and promise potentially valuable additions to the world’s metal resources.The prospects for mining of this marine type of metal deposits largely depend on the grades and the scale of the potential ore resources. However, only a few percent of existing seamounts and guyots have been mapped and sampled in detail, most of them in the Pacific Ocean. Therefore, a model to estimate the geological resources based on the global seamount catalogue of Wessel (2001; revised: Wessel et al., 2009) and the empirical parameters which control the metal composition and distribution was developed."

Jan 1, 2017

By Sven Petersen, Berit Lehrmann, Bramley J. Murton, Paul A. J. Lusty

"INTRODUCTIONToday’s metal mining focusses on land based ore deposits which only consider one third of the Earth’s surface. Through an increasing global demand of strategic metals used in the electronic and green industry (Zepf et al. 2014), ‘uneconomic’ sites of lower grade in more technical challenging grounds such as greater depth and/or more remote areas are developed by the mining industry often resulting in higher environmental impact. However, considering the steady growth of the Earth population a shortage of certain metals may occur (Krausmann et al. 2009). In 2010, the United Nations allowed commercial exploration for seafloor massive sulphides (SMS) in international waters with currently six contractor licenses being granted.Although the number of discovered vent sites has steadily increased since the first discovery of hydrothermal venting at the Galapagos Rift in 1977 (Corliss et al. 1979) with more than 600 sites being known today, their economic potential is poorly constrained. So far Nautilus Minerals Inc., a Canadian mining company, is the only company having conducted a NI 43-101 resource estimate for the Solwara site, located in the territorial waters of Papua New Guinea. Other studies using bulk geochemical data from 95 sites published in literature do exist (Hannington et al. 2011, Monecke et al. 2016) suggesting a global resource potential for today’s known SMS deposits of 600 million tons with a median grade of 3 wt.-% copper, 9 wt.-% zinc, 2 g/t gold and 100 g/t silver. However, the geochemical data being used originated mainly from easily recoverable, mainly non insitu surface grab-samples and are under current mineral resource classification schemes such as JORC code or NI 43-101 not even accepted for resource estimations. Furthermore surface samples such as high-temperature sulphide chimney and talus material are not representative for the entire deposits with information regards thickness and continuity of individual sulphide layers obtained through drilling being scarce. In addition, it remains unknown what geological processes occur once hydrothermal activity ceases and whether metal tenor becomes enriched, depleted or disappears."

Jan 1, 2017

By Makoto Yuasa, Akira Usui, Shipboard Scientists of SIP Cruises, Atsushi Suzuki, Shingo Kato, Kyoko Yamaoka, Akira Nishimura, Kiyo Kisimoto, Katsuhiko Suzuki

"We report here on current topics of our project, based on the results of recent cruises and laboratory analysis, about the diversity of compositions and configurations of the hydrogenetic ferromanganese deposits in several Northwestern Pacific Seamounts. This recent research has discovered important aspects of these deposits regarding the mode of variation with water depth, topography and substrate geology, possible bacterial mediation, temporal variation with age in mineralogy, and major and minor element chemistry. All cruises and analysis have been supported by the facilities and staff of the Japan Agency of Marine-Earth Science and Technology (JAMSTEC), Japan Oil, Gas, and Metal resources Corporation (JOGMEC), Geological Survey of Japan, and Kochi Core Center (KCC) using a remotely operated vehicle (ROV), a monitored rock drilling system, dredges, and manned-submersibles in the NW Pacific seamounts,The results indicate that most of the rock outcrops on the slopes, shoulders, and much of flat tops are covered with maximum 10-cm thick crusts, but the thickness, metal content, and microstructural properties are not always uniform over the seamounts, but variable in space and time. The micro-stratigraphic description of whole-rock samples indicates a history of deposition and sedimentation, which control the diversity in bulk composition and abundance caused by the variable incorporation of iron-manganese precipitates into the deposits during variable environmental conditions. We conclude that hydrogenetic precipitation of iron-manganese oxide has taken place for more than 20 million years at a growth rate about 4-6 mm/my, in water depths below 1000m. The results indicate a fairly continuous and constant metal deposition since the middle Miocene age or older to the present. Our case study of geological sciences at a model seamount within the Japanese EEZ suggests that scientific knowledge is useful and essential in exploring mineral deposits, economic estimation, and designing systems, if supported by well-combined geological and oceanographic and biological research. The distribution map of ferromanganese deposits and geological map will be published soon in 2017 to be issued by the Geological Survey of Japan."

Jan 1, 2017

By Elizabeth McIsaac, Wylie Spicer

"In July 2016 the International Seabed Authority (the “ISA”) released a first working draft of its mineral exploitation regulations as well as the standard contract terms for mineral resources in the Area, for which stakeholder input was sought in late 2016. In January of 2017 the ISA released a discussion paper on environmental matters related to these draft regulations. The ISA is now in the process of further developing its draft exploitation regulations and standard contract terms to ensure that seabed mining is carried out in an environmentally sound way for the common benefit of mankind.As the regulator of the “Area”, the ISA can draw lessons from onshore mining regulators and offshore petroleum regulators for their experiences in legislative drafting to smoothly and safely oversee project development, implementation, and closure. However, one of the unique challenges that the ISA faces in regulating private industry is its status as an international organization and not a sovereign nation, which results in a significantly different legal relationship between the regulator and the regulated. The result is that the exploitation contract is the sole legal connection between the mining proponent and the regulator for the exploitation phrase of the project.Accordingly, in the regulatory development process, the ISA must carefully consider which rights and obligations are set out in the exploitation contract versus the regulations. This decision will dictate the flexibility the ISA will have to modernize the conduct required of mining proponents in response to changing best practices in the industry, technological progress, and advances in the understanding of the marine ecosystem. As the first working draft of the exploitation regulations sets out an initial contract period of twenty years, it is crucial for the ISA to carefully consider the rights, obligations, and procedures it agrees to in the exploitation contract, as unilateral amendment will not be possible after contract execution."

Jan 1, 2017

By Jeremy Spearman, Alan Cooper, Mark Lee, Jon Taylor, Michael Turnbull, Neil Crossouard, Bramley Murton

"SUMMARYSeamounts are underwater mountains caused by volcanic activity. They are of great oceanographic interest because of their local and basin-scale influence over ocean systems, their often unique ecosystems, and because they are associated with the formation of ferromanganese (Fe-Mn) crusts. These crusts are of particular interest to scientists because they are rich in some of the rare elements increasingly required for development of renewable technologies. When the possibility of mining such seamounts is considered, an inter-disciplinary study of seamount hydrodynamics, crust formation and ecosystem sensitivity is required. MarineE-tech is one such multi-disciplined project that has been commissioned to address these different aspects in order to improve understanding of the viability and desirability of mining Fe-Mn crusts. This paper describes a key part of this study, namely the development of a model, informed by hydrographic observations, of the currents around one such seamount and the in situ validation of a sediment disturbance plume model as a pre-cursor to assessment of the potential effects of mining activity.INTRODUCTIONFerromanganese crusts are thought to form by precipitation of iron and manganese oxides from oxygen depleted mid-water known as the oxygen minimum zone (OMZ). Oxidation rich waters, typically at depths of about 800-2200 m (Hein et al, 2000). This range of depths coincides with the flanks and summits of many seamounts. The ferromanganese crusts found on seamounts have been found to have high concentrations of rare elements, like Tellurium, that are considered critical to low-carbon energy production. Seamounts are complex environments: in terms of the local hydrodynamics that tend to trap water over the seamount due to the Taylor Cap effect (e.g. Chapman and Haidvogel, 1992) and which can enhance the productivity of seamount waters through upwelling (Lavelle and Mohn, 2010), in terms of the microbiological activity that leads to the precipitation of the Fe-Mn crusts, and also in terms of the often unique ecosystems that are the product of the “island” nature of seamounts and the upwelling of nutrients. The understanding of this complexity is a necessary journey towards the realization of viable, yet environmentally responsible, mining schemes. The formation of crusts will be influenced by the local (and larger-scale) hydrodynamics. The exploration of promising crust sites could be made much more efficient by understanding where the most prospective deposits are likely to occur. Knowing how to remove these crusts without impacting significantly on the local environment will be a pre-requisite for such mining to be acceptable to the public and funders alike."

Jan 1, 2017

By Chuanshun Li, Haitao Zhang, Xuefa Shi, Quanshu Yan, Zhiwei Zhu

In Expeditions 22 and 26 of China Ocean Survey (COS), Chinese and Russian scientists have Carried out a lot of work to search for hydrothermal sulfide in Southern Mid-Atlantic ridge (SMAR) 19°S, but come back empty-handed at last. The sulfide formation is closely related with the water-rock reactions which are controlled by the heat source. Melt inclusions are considered to have a unique compositions in melt to reflect the deep magma processes. Fortunately, we have found a large number of plagioclase hosted melt inclusions in SMAR19°S MORB. We have done experiments by re-homogenization and re-crystallization of these melt inclusions. During the re-homogenization experiments, the forming and melting processes of the olivine crystal inside the melt inclusions indicate that the homogeneous temperature of melt inclusions is 1190-1200??. During the recrystallization experiments, the different mineral phase assemblages show H2O inside the melt inclusions has hardly ever been loss, in addition Cr element and H2O molecule in SMAR19°S magma are heterogeneity at the time of melt inclusions trapping, and then the re-crystallization experiments provide a method to prove the microheterogeneity of basaltic magma system. Combining with the bulk rock data, this study shows that the melt inclusions are formed at a low-temperature and high-pressure condition. Eventually, this paper speculates that a low temperature heat source generated by a lower mantle potential temperature or/and a thick lithosphere indicated by the melt inclusions that not experienced the H2O loss process are beneath the SMAR19°S. The low temperature heat source transmits its heat to lithosphere through the cooling thermal boundary layer (CTBL), and the thick lithosphere can sufficiently absorb and consume the heat. Under the interaction between the heat source and lithosphere, the residue heat at the infiltration depth of sea water might have been no ability to satisfy the water-rock reactions temperature, therefore, the water-rock reaction should hardly ever appear, so the theoretical reaction zone would not exist beneath the SMAR19°S. Eventually, the interaction between thick lithosphere and the low-temperature heat source should be the dominant factor that makes SMAR19°S area have no condition to form the seafloor sulfide. However, this paper is based on melt inclusions only, in fact, melt inclusions are potential to have melt compositions produced by mineral dissolution, reaction and assimilation, and the volumes of melt inclusions are exceedingly small compared to the overall size of the magmatic systems, therefore, the extrapolation across many orders of magnitude is implicit when applying petrologic information obtained from inclusions to entire magmatic systems. Therefore, there should have other more research to verify the reliability of this conclusion.

Jan 1, 2017

By S. W. Chang, James R. Hein, S-R. Lee, A. Zondervan, H. Choi

"Nine Fe-Mn nodules from the extensive nodule field in the east of Campbell Plateau of southwest Pacific Ocean beneath the Deep Western Boundary Current (DWBC) and Antarctic Circumpolar Current (ACC) were analyzed for the 10Be/9Be dating by AMS (Accelerator Mass Spectroscopy) at IGNS, New Zealand.Several types of nodule morphology were identified including distinctive discoidal forms with overgrowths resulting possibly from overcrowding and partial sediment burial. Five principal nodule facies were also recognized by location and occurrence (Fig. 1) (Wright et al., 2005). Fe-Mn nodules show various concentric internal growth textures, such as, cuspates, large parabolic cuspates, pseudo-columnar, columnar, globular, and laminated, which vary even in a nodule with hydrogenetic, early diagenetic, or mixed origin. Each texture shows micro-textural varieties and different mineralogy and/or chemistry. The genesis of each internal texture was indicated by the REE patterns, the mineralogy of Mnoxides, and the Mn/Fe ratios."

Jan 1, 2017

By Demoor Damien

"The exploitation of marine resources has enjoyed renewed interest with a completely new sector, that of the Deep Sea Mining of mineral resources in the seabed, that is now gaining momentum. Nevertheless, the significant environmental constraints represent a challenge for initiating these new activities, whether this is in terms of the knowledge of the concerned ecosystems or in terms of monitoring and minimizing the impact of these new activities. This paper presents 2 technologies that aim to respond to the expectations of the stakeholders in this area. The first consists of the real-time monitoring of installations/operations and their impact on the environment using the most modern underwater technologies and especially long-term deployment AUV based on AUV docking station solution and autonomous long term observatories. The second consists of a membrane allowing the confinement of an area, the reduction of the emission of particles in suspension and noise reduction.IntroductionDeep ocean environments have been explored since the mid-1800s. As the land-based reserves of hydrocarbons and minerals become depleted, increasing numbers of resourcebased projects are being proposed for shallow then deepwater environments. Two distinct resource sectors have recognized the potential commercial value of working in shallow and deepwater environments – Oil and Gas and now Mining."

Jan 1, 2017

By Youngtak Ko

The northeastern Pacific shows the highest nodule abundance among the oceans in the world, and thus has been drawing international attention for deep-sea manganese nodule development. The objectives of this study are to construct database using geostatistics and geographic information system (GIS), to quantify rating value using probability and statistical methods, to suggest suitable sites for manganese nodule development, and to verify results using three statistical approaches. The copper and nickel contents of the nodules were determined by chemical analysis. Factors related to slope, aspect, water depth, and topography were obtained from multi-beam echo sounding data. The transparent layer thickness was determined using a sub-bottom profiler. The probability method was used to calculate each factor's rating, and the layers for different factors were summed to produce the development potential index (DPI). Result maps were constructed for manganese nodules development. The distribution pattern of DPI showed to be controlled of nodule abundance and metal contents. Verification was performed by comparing the results with sampling data in three ways: success and prediction rate, linear regression, and test of independence.

Sep 14, 2011

By Teruyoshi Narita

In Japan, the Ministry of Economy, Trade and Industry (METI) commenced a research and development (R&D) project on seafloor massive sulphides (SMS) in Japan?s exclusive economic zone (EEZ) in the 2008 fiscal year. In this plan, the road map of Resource evaluation, environmental impact study, mining system technology and processing technology fields consisting of the first and second stage has been shown for the commercialization of SMS. Based on this road map, Japan Oil, Gas and Metals

Sep 14, 2011

By Ivo Dreiseitl

Bottom sediment sampling by means of a box corer, as a direct method of deep seabed exploration for polymetallic nodules, is the most comprehensive way to obtain various types of geological information on points forming a network of stations. However, direct information is lacking from areas separating those stations and has to be approximated by interpolation or extrapolation, which leads to uncertainties. Sediment sampling with a gravity or piston corer can provide information on the superficial, up to 4 m thick, part of the sedimentary cover. As opposed to box coring, gravity or piston coring provides no information on nodule abundance. Information for unsampled areas can be gained by application of remote techniques of exploration. The techniques of choice in visualising nodule-rich fields, nodule-free areas, hard rock outcrops and other obstacles for seafloor mining involve using sonar and continuous deep sea (CDS) camera. Seafloor mapping can be rendered with two major sonar types: the side scan sonar used to obtain seafloor imagery and multibeam sonar for bathymetric data; the two types are usually combined and work with an intermediate frequency profiler. Photo-profiling by means of a deep sea towed camera provides a series of seafloor photographs, each supplemented with information on the area covered by each frame, including the nodule abundance. Remote techniques have been quite frequently applied by the Interoceanmetal Joint Organization (IOM) in nodule field exploration. Recently, geoacoustic techniques (side scan sonar + profiler) and CDS were applied for exploration of IOM?s first prime area H11 (5372 km2) on 6 transects. During the IOM-2009 cruise, a total of 295 km of geoacoustic transects and 344 km of photo-transects were surveyed. The data obtained were processed with the aid of earlier information produced by multibeam sonar surveys. The aim of this paper is to demonstrate the advantages of remote techniques, particularly with regard to application of the towfish device, for geological and geotechnical applications in exploration for polymetallic nodules.

Sep 14, 2011

By Sven Petersen

The southern Mid-Atlantic Ridge (SMAR) is one of the least-explored spreading centers in the world with respect to hydrothermal activity. In the past 8 years research focused mainly on the ridge segments close to Ascension Island, discovering hydrothermal fields as far south as 14°20?S (Haase et al., 2007; German et al., 2008; Tao et al., 2011). However, the vast majority of the SMAR ridge axis has never been thoroughly investigated for hydrothermal activity. In the spring of 2013 we used segment-scale AUV deployments as well as conventional CTD surveys to identify areas of hydrothermal activity along 16 mid-ocean ridge segments between 13° and 33°S, thereby covering close to 5 % of the global ridge axis in a single cruise. During cruise MSM25 of the German research vessel Maria S. Merian, we tested longrange (>100 km lines per dive) AUV deployments of GEOMAR?s AUV ABYSS (a Remus 6000 vehicle) along the spreading axis for their capability to locate active venting in a fast and efficient way on regional surveys. Since the missions covered long distances,

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

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

Sep 14, 2011

By S. Kim Juniper

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

Sep 14, 2011

By Carsten Rühlemann

Between 2008 and 2013, the German Federal Institute for Geosciences and Natural Resources (BGR) carried out five exploration cruises to the German license area in the eastern Pacific Nodule Belt. The first two expeditions were mainly dedicated to multibeam mapping to obtain an overview of the seafloor topography and acoustic backscatter strength. These data were used to identify ten to fourteen prospective nodule fields for potential future mining, which together cover about 16% of the total license area of 75,000 km2. During the last three cruises, three of these potential mining areas were explored in detail. For this purpose, the BGR developed a suite of exploration methods to map nodule size distributions and nodule abundances. These methods include acoustic surveys with vessel-based multibeam systems as well as near-bottom video mapping complemented by in situ sampling. The economically most valuable field has a size of ca. 2,000 km2, of which 34% is covered by medium to large nodules (> 4 cm long axis of nodules) with an average abundance of 22.4 kg/m2 and 44% is covered by small nodules (< 4 cm) with a mean abundance of 17.5 kg/m2. The total mass of nodules in this field comprises more than 30 million tons wet weight and could sustain deep-sea mining for at least 10 years.

Sep 14, 2011

By James R. Hein

Manganese nodules from the Cook Islands (CI) Exclusive Economic Zone (EEZ) are compositionally different from other nodule fields. CI nodules have relatively high cobalt concentrations and low nickel, copper, and manganese concentrations (e.g. Hein and Petersen, 2013). This reflects the predominantly hydrogenetic (seawater source) origin for metals in the CI nodules versus dual seawater-pore water sources for most other nodules. The concentrations of many critical and strategic metals have not been previously analyzed for CI nodules, so comparisons with other nodule fields have been limited. To address this, we analyzed a set of nodules distributed throughout the CI EEZ for a complete set of 67 elements, including all of the metals that may be of economic interest, such as the rare earth elements (REEs), yttrium, tellurium, niobium, zirconium, tungsten, titanium, and others (see selected elements in Table 1). In addition, we recalculated the tonnages of nodules and contained metals from nodule abundance areas (in square kilometers) determined by GIS ArcMap calculations based on JICA/MMAJ (2001) nodule distributions. The nodule tonnage calculated and summed from each abundance sector yields a total inferred resource estimate of 9.66 billion tonnes of nodules covering an area of 1.21 million square kilometers; using a cut-off of 6 kilograms of nodules per square meter, yields a median tonnage of 8.59 billion tonnes of nodules covering 687,647 square kilometers (Table 2).

Sep 14, 2011

By T. Schoening

The exploration of the seafloor regarding the abundances of poly-metallic nodules has received growing attention recently. Image-based exploration using cameraequipped deep-sea observation systems has been introduced successfully to increase spatial resolution in the exploration process but the evaluation and interpretation of the huge amount of image data creates a serious bottleneck. In this paper we present a new software solution to the problem of automatic detection and segmentation of poly-metallic nodules in underwater images, which is not only accurate but so fast that real time image analysis is definitely in reach. Thus, an application on an AUV (Autonomous Underwater Vehicle) seems possible in the near future.

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 Ye Jun

Until now, more than 200 sites of sea-floor hydrothermal activities are known on the midocean ridge but few of them are documented on South Mid-Atlantic Ridge (SMAR). This on some extent restricts our directly understanding of the hydrothermal mechanism on SMAR. In 2011, During the Cruise 22 of R/V Dayangyihao, a masive sulfide field was discovered in the center part of the first-order ridge segment that bounded between Cardno Fracture Zone and Saint Helena Fracture Zone, near 15.16°S/13.35°W, which give us an opportunity to recognize the mechanism of hydrothermal systems on SMAR directly. This newly discovered hydrothermal field, which informally called SMAR 15°S, is situated in a SE-NW offset depression of an axial neovolcanic ridge, with water depth of about 2793m. In the water column around this field, strong turbidity and temperature anomalies were detected. Ten meters high venting chimneys, hydrothermal mounds as well as a large amount of hydrothermal vent shrimps were also observed and recorded by ROV and Deep tow camera on the ocean floor. The samples we collected from this field include sulfide chimney fragments, massive sulfides and basaltic rocks. In this study, we are focusing on the mineralogy and sulfur isotope geochemistry of sulfide samples for preliminarily uncovering the geological characteristics and hydrothermal processes of this hydrothermal field.

Sep 14, 2011