The distribution characteristics of methyl mercury in Rana chensinensis and water,sediment and soil in gold-mining areas of the upper reaches of the Songhua River,China were studied by field sampling and laboratory te...The distribution characteristics of methyl mercury in Rana chensinensis and water,sediment and soil in gold-mining areas of the upper reaches of the Songhua River,China were studied by field sampling and laboratory testing.The results show that the methyl mercury contents in water,sediment and soil in gold-mining areas are much higher than those in the control site,indicating that gold-mining activities intensify the methyl mercury pollution in the study area.Methyl mercury contents are in a descending order of sediment > soil > water in the environment,and in a descending order of brain > viscera > muscle > skin in Rana chensinensis.There are significant correlation between methyl mercury contents in Rana chensinensis and those in water and sediment.In particular,the methyl mercury content in the skin of Rana chensinensis is positively correlated with those in water and sediment in spring.Therefore,skin is one of main intake pathways for methyl mercury due to its high permeability.展开更多
The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of China. Of a great variety of gold deposits present in this area, the following t...The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of China. Of a great variety of gold deposits present in this area, the following types seem to be economically most valuable and promising: tectonic alteration type in ophiolitic melange; polymetallic quartz vein type related to intermediate-acid intrusions; finely disseminated type in fracture zones; mixed hydrothermal type in tectonic fractures of carbonate rocks; hydrothermal type related to subvolcanic rocks; volcanic-hot spring type; submarine volcano exhalation-sedimentary-hydrothermal reformation type. Metallogenic epochs are exclusively Mesozoic and Cenozoic, and ore deposits and orebodies are controlled by linear structures. Magmatic activity has affected gold mineralization in varying degrees, and gold deposits are basically of mesothermal-epithermal type with ubiquitous and intense alterations. Ore-forming materials and hydrothermal solutions show multi-source character.展开更多
The Berezitovoe deposit in the Sergachi volcano-plutonic and metallogenic belt preserves evidence for polymetallic mineralization of multiple stages.The steeply dipping gamet-tourmaline-muscovite-quartz metasomatites...The Berezitovoe deposit in the Sergachi volcano-plutonic and metallogenic belt preserves evidence for polymetallic mineralization of multiple stages.The steeply dipping gamet-tourmaline-muscovite-quartz metasomatites（with K-Ar ages of 132 ± 2.9 and 127 ± 4.4 Ma） carry two distinct stages of mineralization developed at different times：（1） polymetallic mineralization and（2） gold-quartz.The deposit is located within Paleozoic gneissose granitoids of the Pikansky complex（dated as 379 ± 1.1 Ma by zircon U-Pb method） intruded by early Cretaceous porphyry-like granites of the Haikta pluton（dated as137 ± 0.67 Ma by zircon U-Pb method） and late Cretaceous dikes of porphyrites,porphyries,and lamprophyres.Evidence suggests the action of late gold-bearing hydrothermal fluids on the early polymetallic ores and the selective mobilization of some elements from these lead to redeposition together with complex sulphosalts.展开更多
The Puyango River Basin covers approximately an area of 4400 km2, it is located in Southern of Ecuador, with Calera and Amarillo rivers as tributaries. In this region, one of the main activities is small scale gold an...The Puyango River Basin covers approximately an area of 4400 km2, it is located in Southern of Ecuador, with Calera and Amarillo rivers as tributaries. In this region, one of the main activities is small scale gold and silver mining. Currently there are 110 processing plants on the bank of Calera and Amarillo rivers, causing a significant degradation of natural resources. A seasonal comparison of metal concentrations in surface water, sediments and particulate matter from the Puyango River and its effluents is made. It was done a differentiation between natural contaminations with the anthropogenic one generated by mining activity. Samples were taken during dry season (2004) and rainy season (2006), and analyzed physicochemical parameters, anions and cations and the concentrations of heavy metals. The results show a clear influence of gold mining in Puyango River contamination, starting with its tributaries, Calera and Amarillo rivers, which have the highest concentrations of heavy metals from the basin, corresponding with the location of the mineral processing plants.展开更多
On the contiguous territories of Russia and China, along the left and right banks of the Amur River (Heilongjiang Province of China, and Amur Oblast’ of Russia), several Precambrian protrusions (Gonzhinsk, Mamynsk, A...On the contiguous territories of Russia and China, along the left and right banks of the Amur River (Heilongjiang Province of China, and Amur Oblast’ of Russia), several Precambrian protrusions (Gonzhinsk, Mamynsk, Amurkhe, and Khumakhe) are known. On the Russian territory, along the setting and on the area of the protrusions, lode manifestations, precious-metal deposits, and gold-platinoid placers are known having the industrial importance. Ultramafites are metasomatically altered more likely by the action of the Late Paleozoic intrusions and produced by them hydrothermae, and are transformed into listvenites. It can be concluded that as one of the sources of precious metals in the placers were the aureoles of listvenitization. This is evidenced by the presence of talc (typomorphic mineral of apoultrabasites) inclusions together with Pt-, Pd- and Ir-bearing gold in the corrosive coatings of the primary platinoids. This conclusion requires the revision of the work strategy of prospecting the lode gold and PGE manifestations within the ore-placer node because apoultrabasites before were considered non-promising for precious metals.展开更多
This study aims to evaluate the mineral pollution of a gold mining environment in the sub-Prefecture of Zouan-Hounien (C?;te d’Ivoire). Samples were taken from surface water and flesh and skin samples of the Cavally ...This study aims to evaluate the mineral pollution of a gold mining environment in the sub-Prefecture of Zouan-Hounien (C?;te d’Ivoire). Samples were taken from surface water and flesh and skin samples of the Cavally River fish species over a period of two successive years. Concentrations in major elements, trace elements (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn), nutrients () and physico-chemical parameters in situ were measured. The results obtained show that the surface waters have very low pH with an average of 5.70. For nutrient salts, the deterioration of water quality in the study area is mainly related to alterations by nitrates, phosphates and sulphates. The concentrations of Fe, Cu, Hg and Pb are above the existing standards (international, FAO/WHO) for the majority of the stations, thus causing the deterioration of the surface water quality. Therefore, their use for agricultural irrigation could have negative impact on the health of the population and on biodiversity. Regarding the bioindicating species, the results obtained after analysis of samples showed that the fish (carp and machoiron) have Fe, Cu, Hg and Pb concentrations higher than the existing standards (international, FAO/WHO) exposing consumers to high health risks. This study showed good correlation between the high values of surface water turbidity and the proximity of gold washing sites. The use of the principal component analysis (PCA) of the physicochemical dataset revealed comparable behaviors for certain minerals within the groups (Fe, K, Mg, Mn and Na) and (As, Cd, Cu, Ni, Pb, Zn and Ca) in water. The Ascending Hierarchical Classification (AHC) analysis has defined three different classes of surface water in the study area. The presence of mineral trace elements in these receiving environments is of natural origin but would be strongly accentuated by human activities.展开更多
基金Under the auspices of National Natural Science Foundation of China (No. 40673059)Testing Foundation of Northeast Normal University
文摘The distribution characteristics of methyl mercury in Rana chensinensis and water,sediment and soil in gold-mining areas of the upper reaches of the Songhua River,China were studied by field sampling and laboratory testing.The results show that the methyl mercury contents in water,sediment and soil in gold-mining areas are much higher than those in the control site,indicating that gold-mining activities intensify the methyl mercury pollution in the study area.Methyl mercury contents are in a descending order of sediment > soil > water in the environment,and in a descending order of brain > viscera > muscle > skin in Rana chensinensis.There are significant correlation between methyl mercury contents in Rana chensinensis and those in water and sediment.In particular,the methyl mercury content in the skin of Rana chensinensis is positively correlated with those in water and sediment in spring.Therefore,skin is one of main intake pathways for methyl mercury due to its high permeability.
文摘The Jinsha River-Lancang River-Nujiang River area is one of the important prospect areas for noble metal and nonferous metal deposits of China. Of a great variety of gold deposits present in this area, the following types seem to be economically most valuable and promising: tectonic alteration type in ophiolitic melange; polymetallic quartz vein type related to intermediate-acid intrusions; finely disseminated type in fracture zones; mixed hydrothermal type in tectonic fractures of carbonate rocks; hydrothermal type related to subvolcanic rocks; volcanic-hot spring type; submarine volcano exhalation-sedimentary-hydrothermal reformation type. Metallogenic epochs are exclusively Mesozoic and Cenozoic, and ore deposits and orebodies are controlled by linear structures. Magmatic activity has affected gold mineralization in varying degrees, and gold deposits are basically of mesothermal-epithermal type with ubiquitous and intense alterations. Ore-forming materials and hydrothermal solutions show multi-source character.
基金the financial support of the Presidium and Far East Branch of the Russian Academy of Sciences (Grant No.15-1-2-019)the Russian Foundation for Basic Research(Grant No.15-05-00809)+1 种基金supported by the Talent Award to M.Santosh from the 1000 Plan of the Chinese Governmentthe Foreign Expert grants from China University of Geosciences(Beijing)
文摘The Berezitovoe deposit in the Sergachi volcano-plutonic and metallogenic belt preserves evidence for polymetallic mineralization of multiple stages.The steeply dipping gamet-tourmaline-muscovite-quartz metasomatites（with K-Ar ages of 132 ± 2.9 and 127 ± 4.4 Ma） carry two distinct stages of mineralization developed at different times：（1） polymetallic mineralization and（2） gold-quartz.The deposit is located within Paleozoic gneissose granitoids of the Pikansky complex（dated as 379 ± 1.1 Ma by zircon U-Pb method） intruded by early Cretaceous porphyry-like granites of the Haikta pluton（dated as137 ± 0.67 Ma by zircon U-Pb method） and late Cretaceous dikes of porphyrites,porphyries,and lamprophyres.Evidence suggests the action of late gold-bearing hydrothermal fluids on the early polymetallic ores and the selective mobilization of some elements from these lead to redeposition together with complex sulphosalts.
文摘The Puyango River Basin covers approximately an area of 4400 km2, it is located in Southern of Ecuador, with Calera and Amarillo rivers as tributaries. In this region, one of the main activities is small scale gold and silver mining. Currently there are 110 processing plants on the bank of Calera and Amarillo rivers, causing a significant degradation of natural resources. A seasonal comparison of metal concentrations in surface water, sediments and particulate matter from the Puyango River and its effluents is made. It was done a differentiation between natural contaminations with the anthropogenic one generated by mining activity. Samples were taken during dry season (2004) and rainy season (2006), and analyzed physicochemical parameters, anions and cations and the concentrations of heavy metals. The results show a clear influence of gold mining in Puyango River contamination, starting with its tributaries, Calera and Amarillo rivers, which have the highest concentrations of heavy metals from the basin, corresponding with the location of the mineral processing plants.
文摘On the contiguous territories of Russia and China, along the left and right banks of the Amur River (Heilongjiang Province of China, and Amur Oblast’ of Russia), several Precambrian protrusions (Gonzhinsk, Mamynsk, Amurkhe, and Khumakhe) are known. On the Russian territory, along the setting and on the area of the protrusions, lode manifestations, precious-metal deposits, and gold-platinoid placers are known having the industrial importance. Ultramafites are metasomatically altered more likely by the action of the Late Paleozoic intrusions and produced by them hydrothermae, and are transformed into listvenites. It can be concluded that as one of the sources of precious metals in the placers were the aureoles of listvenitization. This is evidenced by the presence of talc (typomorphic mineral of apoultrabasites) inclusions together with Pt-, Pd- and Ir-bearing gold in the corrosive coatings of the primary platinoids. This conclusion requires the revision of the work strategy of prospecting the lode gold and PGE manifestations within the ore-placer node because apoultrabasites before were considered non-promising for precious metals.
文摘This study aims to evaluate the mineral pollution of a gold mining environment in the sub-Prefecture of Zouan-Hounien (C?;te d’Ivoire). Samples were taken from surface water and flesh and skin samples of the Cavally River fish species over a period of two successive years. Concentrations in major elements, trace elements (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn), nutrients () and physico-chemical parameters in situ were measured. The results obtained show that the surface waters have very low pH with an average of 5.70. For nutrient salts, the deterioration of water quality in the study area is mainly related to alterations by nitrates, phosphates and sulphates. The concentrations of Fe, Cu, Hg and Pb are above the existing standards (international, FAO/WHO) for the majority of the stations, thus causing the deterioration of the surface water quality. Therefore, their use for agricultural irrigation could have negative impact on the health of the population and on biodiversity. Regarding the bioindicating species, the results obtained after analysis of samples showed that the fish (carp and machoiron) have Fe, Cu, Hg and Pb concentrations higher than the existing standards (international, FAO/WHO) exposing consumers to high health risks. This study showed good correlation between the high values of surface water turbidity and the proximity of gold washing sites. The use of the principal component analysis (PCA) of the physicochemical dataset revealed comparable behaviors for certain minerals within the groups (Fe, K, Mg, Mn and Na) and (As, Cd, Cu, Ni, Pb, Zn and Ca) in water. The Ascending Hierarchical Classification (AHC) analysis has defined three different classes of surface water in the study area. The presence of mineral trace elements in these receiving environments is of natural origin but would be strongly accentuated by human activities.
