Seafloor massive sulfide（SMS） deposits which consist of Au, Ag, Cu, and other metal elements, have been a target of commercial mining in recent decades. The demand for established and reliable commercial mining syst...Seafloor massive sulfide（SMS） deposits which consist of Au, Ag, Cu, and other metal elements, have been a target of commercial mining in recent decades. The demand for established and reliable commercial mining system for SMS deposits is increasing within the marine mining industry. The current status and progress of mining technology and equipment for SMS deposits are introduced. First, the mining technology and other recent developments of SMS deposits are comprehensively explained and analyzed. The seafloor production tools manufactured by Nautilus Minerals and similar mining tools from Japan for SMS deposits are compared and discussed in turn. Second, SMS deposit mining technology research being conducted in China is described, and a new SMS deposits mining tool is designed according to the environmental requirement. Finally, some new trends of mining technology of SMS deposits are summarized and analyzed. All of these conclusions and results have reference value and guiding significance for the research of SMS deposit mining in China.展开更多
JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Tra...JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Trade and Industry）, for the commercialization of SMS （Seafloor Massive Sulfide）. As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.展开更多
Deformation characteristics and constitutive model of seafloor massive sulfide(SMS)were selected as the research object.Uniaxial/triaxial compression test were carried out on the mineral samples,and the deformation ch...Deformation characteristics and constitutive model of seafloor massive sulfide(SMS)were selected as the research object.Uniaxial/triaxial compression test were carried out on the mineral samples,and the deformation characteristics of specimens under various conditions were studied.According to characteristics of the mineral,a new three stages constitutive equation was proposed.The conclusions are as follows:The axial strain,peak strain and maximum strength of seafloor massive sulfide increase with the confining pressure.The elastic modulus of the metal sulfide samples is decreased sharply with the increase of confining pressure.According to characteristics of seafloor massive sulfide,the constitutive equation is divided into three parts,the comparison between theoretical curves and experimental data shows that both of them are in good agreement,which also proves the correctness of the constitutive equation for uniaxial compression.展开更多
Helium, neon and argon isotope compositions of fluid inclusions have been measured in massive sulfide samples from theJade hydrothermal field in the central Okinawa Trough. Fluid-inclusion 3He/4He ratios are between 6...Helium, neon and argon isotope compositions of fluid inclusions have been measured in massive sulfide samples from theJade hydrothermal field in the central Okinawa Trough. Fluid-inclusion 3He/4He ratios are between 6.2 and 10.1 times theair value (Ra), and with a mean of 7.8Ra, which are consistent with the mid-ocean ridge basalt values [3He/4He≈(6Ra^11Ra)]. Values for 20Ne/22Ne are from 10.7 to 11.3, which are significantly higher than the atmospheric ratio (9.8).And the fluid-inclusion 40Ar/36Ar ratios range from 287 to 334, which are close to the atmosperic values (295.5). Theseresults indicate that the noble gases of trapped hydrothermal fluids in massive sulfides are a mixture of mantle- andseawater-derived components, and the helium of fluid inclusions is mainly from mantle, the nelium and argon isotopecompositions are mainly from seawater.展开更多
The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previ...The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide deposits.However,the sulfide chronology and hydrothermal activity of the YHF remain poorly constrained.In this study,mineralogical analyses and 230Th/U dating were performed.Hydrothermal activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the YHF.The 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the SWIR.Hydrothermal activity in the SWIR has been relatively active over the past20 ka.In contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in duration.The maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 ka.There was a slight positive correlation between the maximal age and estimated surface area or estimated tonnage.The minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic systems.The ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)deposits.The results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51074179)National Hi-tech Research and Development Program of China(863 Program,Grant No.2012AA091291)Basic Research Foundation of Shenzhen Science and Technology Innovation,China(Grant No.JCYJ20150929102555935)
文摘Seafloor massive sulfide（SMS） deposits which consist of Au, Ag, Cu, and other metal elements, have been a target of commercial mining in recent decades. The demand for established and reliable commercial mining system for SMS deposits is increasing within the marine mining industry. The current status and progress of mining technology and equipment for SMS deposits are introduced. First, the mining technology and other recent developments of SMS deposits are comprehensively explained and analyzed. The seafloor production tools manufactured by Nautilus Minerals and similar mining tools from Japan for SMS deposits are compared and discussed in turn. Second, SMS deposit mining technology research being conducted in China is described, and a new SMS deposits mining tool is designed according to the environmental requirement. Finally, some new trends of mining technology of SMS deposits are summarized and analyzed. All of these conclusions and results have reference value and guiding significance for the research of SMS deposit mining in China.
文摘JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Trade and Industry）, for the commercialization of SMS （Seafloor Massive Sulfide）. As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.
基金Project(2012AA091291)supported by the National High-tech Research and Development Program of ChinaProject(51074179)supported by the National Natural Science Foundation of ChinaProjects(JCYJ20130401160614378,JCYJ20140506150310437)supported by Shenzhen Science and Technology Innovation Basic Research Foundation,China
文摘Deformation characteristics and constitutive model of seafloor massive sulfide(SMS)were selected as the research object.Uniaxial/triaxial compression test were carried out on the mineral samples,and the deformation characteristics of specimens under various conditions were studied.According to characteristics of the mineral,a new three stages constitutive equation was proposed.The conclusions are as follows:The axial strain,peak strain and maximum strength of seafloor massive sulfide increase with the confining pressure.The elastic modulus of the metal sulfide samples is decreased sharply with the increase of confining pressure.According to characteristics of seafloor massive sulfide,the constitutive equation is divided into three parts,the comparison between theoretical curves and experimental data shows that both of them are in good agreement,which also proves the correctness of the constitutive equation for uniaxial compression.
基金This work was financially supported in part by the Pilot Project of Knowledge Innovation Project,Chinese Academy of Sciences under contract No.KZCX3-SW-223the Special Foundation for the Tenth Five Plan of COMR A under contract No.DY 105-01-03-1+1 种基金the National M ajor Fundamental Research and Development Project of China under contract No.G2000046701the National Natural Science Foundation of China under contract No.40376020,40176020.
文摘Helium, neon and argon isotope compositions of fluid inclusions have been measured in massive sulfide samples from theJade hydrothermal field in the central Okinawa Trough. Fluid-inclusion 3He/4He ratios are between 6.2 and 10.1 times theair value (Ra), and with a mean of 7.8Ra, which are consistent with the mid-ocean ridge basalt values [3He/4He≈(6Ra^11Ra)]. Values for 20Ne/22Ne are from 10.7 to 11.3, which are significantly higher than the atmospheric ratio (9.8).And the fluid-inclusion 40Ar/36Ar ratios range from 287 to 334, which are close to the atmosperic values (295.5). Theseresults indicate that the noble gases of trapped hydrothermal fluids in massive sulfides are a mixture of mantle- andseawater-derived components, and the helium of fluid inclusions is mainly from mantle, the nelium and argon isotopecompositions are mainly from seawater.
基金The National Key R&D Program of China under contract No.2022YFE0140200the National Natural Science Foundation of China under contract Nos 42127807 and 42006074+1 种基金the China Ocean Mineral Resources R&D Association Project under contract Nos DY135-S1-1-02 and DY135-S1-1-01the Macao Science and Technology Development Fund under contract No.FDCT-002/2018/A1。
文摘The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide deposits.However,the sulfide chronology and hydrothermal activity of the YHF remain poorly constrained.In this study,mineralogical analyses and 230Th/U dating were performed.Hydrothermal activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the YHF.The 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the SWIR.Hydrothermal activity in the SWIR has been relatively active over the past20 ka.In contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in duration.The maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 ka.There was a slight positive correlation between the maximal age and estimated surface area or estimated tonnage.The minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic systems.The ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)deposits.The results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges.
