The rare earth elements(REE)geochemistry and the isotope(δ^(13)C,δ^(18)O)composition of manganese ores of the Chiatura(Georgia)deposit were studied.One of the major features of all types of manganese ores is negativ...The rare earth elements(REE)geochemistry and the isotope(δ^(13)C,δ^(18)O)composition of manganese ores of the Chiatura(Georgia)deposit were studied.One of the major features of all types of manganese ores is negative cerium(Ce/Ce*_(PAAS))anomaly and the absence of europium(Eu/Eu*_(PAAS))anomaly.Oxide oolitic manganese ores were formed in oxic shallow marine environments.The content and distribution of REEs(in particular Ce and Eu)in these ores are connected mainly with ferrous oxides.The performed C-and O-isotope research in Mn-carbonates(oolitic and massive)has indicated that carbonate ores were formed by the participation of isotopic ally light CO_(2)which is a result of the oxidation of organic matter in the sediment strata by reducing environments of early diagenesis(and,partially,catagenesis)zone.Obtained negative cerium anomalies in the studied carbonate ores reflect the specific REE patterns in pore waters of sediments of earlier isdiagenesis zone of the Oligocene Chiatura's basin.The deficiency of cerium in this zone remains debatable and requires further study.Formation of manganese carbonates took place multistage by the input of incisional solutions of different chemistry into sea bottom waters and sediments.The absence of europium anomaly indicates about lack of hydrothermal solution input.展开更多
<正>白云鄂博稀土-铌-铁矿床位于华北地块北缘,内蒙古包头市以北150 km处,东经106~112°,北纬39~42°,地跨华北地台及内蒙海西地槽两大构造单元,台槽之间被白云鄂博北面的乌兰宝力格深大断裂所隔开,以北为内蒙海西地槽区...<正>白云鄂博稀土-铌-铁矿床位于华北地块北缘,内蒙古包头市以北150 km处,东经106~112°,北纬39~42°,地跨华北地台及内蒙海西地槽两大构造单元,台槽之间被白云鄂博北面的乌兰宝力格深大断裂所隔开,以北为内蒙海西地槽区。它是全世界最大的轻稀土矿床,其轻稀土元素储量占全球总储量的50%左右(美国地质调查局,2011),该矿床的铌储量位居世界第二,且又是一个大型的铁矿。该矿床的地质历史复杂,从地层沉积至今经历了至少11次的地质事件(Smith et al.,2000)。展开更多
The REE transportation in two sorts of mylonites of ductile shear zone, in Hetai gold deposit, Guangdong province was studied. The results show that there is REE compositional variation regularly in the ductile shear ...The REE transportation in two sorts of mylonites of ductile shear zone, in Hetai gold deposit, Guangdong province was studied. The results show that there is REE compositional variation regularly in the ductile shear zone. When mica-quartz schist and migmatite are changing into mylonites or ultramylonites, i.e., along with intensifying deformation, the contents of each rare earth element and the total contents of the LREE, HREE and REE increase or decrease regularly, but the REE patterns of the rock are accordant. The isocon diagram of the tectonic rocks before and after deformation shows that the REE compositional variation of the mylonites or ultramylonites are very small, but there is a few REE moving in or out in the rock deformation. The reason of the REE compositional variation is that there are volume change and fluid flow in the rock deformation, and it leads to the LREE relative enrichment and HREE relative loss.展开更多
基金accomplished in accordance with the Research Program of the Geological Institute of the Russian Academy of Sciences。
文摘The rare earth elements(REE)geochemistry and the isotope(δ^(13)C,δ^(18)O)composition of manganese ores of the Chiatura(Georgia)deposit were studied.One of the major features of all types of manganese ores is negative cerium(Ce/Ce*_(PAAS))anomaly and the absence of europium(Eu/Eu*_(PAAS))anomaly.Oxide oolitic manganese ores were formed in oxic shallow marine environments.The content and distribution of REEs(in particular Ce and Eu)in these ores are connected mainly with ferrous oxides.The performed C-and O-isotope research in Mn-carbonates(oolitic and massive)has indicated that carbonate ores were formed by the participation of isotopic ally light CO_(2)which is a result of the oxidation of organic matter in the sediment strata by reducing environments of early diagenesis(and,partially,catagenesis)zone.Obtained negative cerium anomalies in the studied carbonate ores reflect the specific REE patterns in pore waters of sediments of earlier isdiagenesis zone of the Oligocene Chiatura's basin.The deficiency of cerium in this zone remains debatable and requires further study.Formation of manganese carbonates took place multistage by the input of incisional solutions of different chemistry into sea bottom waters and sediments.The absence of europium anomaly indicates about lack of hydrothermal solution input.
文摘<正>白云鄂博稀土-铌-铁矿床位于华北地块北缘,内蒙古包头市以北150 km处,东经106~112°,北纬39~42°,地跨华北地台及内蒙海西地槽两大构造单元,台槽之间被白云鄂博北面的乌兰宝力格深大断裂所隔开,以北为内蒙海西地槽区。它是全世界最大的轻稀土矿床,其轻稀土元素储量占全球总储量的50%左右(美国地质调查局,2011),该矿床的铌储量位居世界第二,且又是一个大型的铁矿。该矿床的地质历史复杂,从地层沉积至今经历了至少11次的地质事件(Smith et al.,2000)。
文摘The REE transportation in two sorts of mylonites of ductile shear zone, in Hetai gold deposit, Guangdong province was studied. The results show that there is REE compositional variation regularly in the ductile shear zone. When mica-quartz schist and migmatite are changing into mylonites or ultramylonites, i.e., along with intensifying deformation, the contents of each rare earth element and the total contents of the LREE, HREE and REE increase or decrease regularly, but the REE patterns of the rock are accordant. The isocon diagram of the tectonic rocks before and after deformation shows that the REE compositional variation of the mylonites or ultramylonites are very small, but there is a few REE moving in or out in the rock deformation. The reason of the REE compositional variation is that there are volume change and fluid flow in the rock deformation, and it leads to the LREE relative enrichment and HREE relative loss.
