Plant species distributing in three Cu mining area were investigated, and Cu concentrations in soils and plants were analyzed. The results showed that Cu ore deposit mostly was distributed at the altitude of about 630...Plant species distributing in three Cu mining area were investigated, and Cu concentrations in soils and plants were analyzed. The results showed that Cu ore deposit mostly was distributed at the altitude of about 630 m. Elsholtzia splendens and Rumex acetosa were distributed only on the Cu ore deposit or the place with high Cu concentration, and the maximum Cu concentrations in these two plants were 1060 mg·kg -1 DW and 1006 mg·kg -1 DW, which reached the critical of hyperaccumulator. Cu accumulations in Elsholtzia splendens and Rumex acetosa were positively and closely correlated with Cu concentration in soil.展开更多
Zircon U-Pb geochronology and geochemistry of the granodiorites in Xiarihamu Cu-Ni mining area are studied to determine the formation age,genesis and tectonic setting. The results show that the granodiorites formed in...Zircon U-Pb geochronology and geochemistry of the granodiorites in Xiarihamu Cu-Ni mining area are studied to determine the formation age,genesis and tectonic setting. The results show that the granodiorites formed in the Middle Triassic with weighted average age of 242 ± 1 Ma. The granodiorites comprise of SiO_2 of 61. 34%--62. 54%,Al_2 O_3 of 16. 46%--16. 87%,MgO of 2. 37%--2. 66%,( Na_2 O + K_2 O) of 5. 39%--5. 74%with the Na2 O/K_2 O of 1. 46--1. 88,Mg~# of 47. 03--48. 04,and show metaluminous characteristics with A/CNK of 0. 94--0. 96,belonging to calc-alkaline I-type granites geochemically. The light and heavy rare earth elements in the rocks are distinctly fractionated and have " right-inclined" distribution patterns with weak negative Eu anomalies( δEu = 0. 84--0. 91). Moreover,these samples show enrichments in LILEs( e. g.,Rb,Ba,K and Sr),especially in Sr [( 343--452) × 10^(-6)],and obvious depletions in HFSEs( e. g.,Nb,Ta,Ti and P),indicating geochemical characteristics similar to subduction-related magmatic rocks. According to the regional tectonic evolution,the Xiarihamu granodiorites were emplaced under an Andean-type active continental margin environment in the early Indosinian,possessing a crust-mantle mixing origin.展开更多
文摘Plant species distributing in three Cu mining area were investigated, and Cu concentrations in soils and plants were analyzed. The results showed that Cu ore deposit mostly was distributed at the altitude of about 630 m. Elsholtzia splendens and Rumex acetosa were distributed only on the Cu ore deposit or the place with high Cu concentration, and the maximum Cu concentrations in these two plants were 1060 mg·kg -1 DW and 1006 mg·kg -1 DW, which reached the critical of hyperaccumulator. Cu accumulations in Elsholtzia splendens and Rumex acetosa were positively and closely correlated with Cu concentration in soil.
基金Supported by Project of Qinghai Bureau of Geological Survey,2017
文摘Zircon U-Pb geochronology and geochemistry of the granodiorites in Xiarihamu Cu-Ni mining area are studied to determine the formation age,genesis and tectonic setting. The results show that the granodiorites formed in the Middle Triassic with weighted average age of 242 ± 1 Ma. The granodiorites comprise of SiO_2 of 61. 34%--62. 54%,Al_2 O_3 of 16. 46%--16. 87%,MgO of 2. 37%--2. 66%,( Na_2 O + K_2 O) of 5. 39%--5. 74%with the Na2 O/K_2 O of 1. 46--1. 88,Mg~# of 47. 03--48. 04,and show metaluminous characteristics with A/CNK of 0. 94--0. 96,belonging to calc-alkaline I-type granites geochemically. The light and heavy rare earth elements in the rocks are distinctly fractionated and have " right-inclined" distribution patterns with weak negative Eu anomalies( δEu = 0. 84--0. 91). Moreover,these samples show enrichments in LILEs( e. g.,Rb,Ba,K and Sr),especially in Sr [( 343--452) × 10^(-6)],and obvious depletions in HFSEs( e. g.,Nb,Ta,Ti and P),indicating geochemical characteristics similar to subduction-related magmatic rocks. According to the regional tectonic evolution,the Xiarihamu granodiorites were emplaced under an Andean-type active continental margin environment in the early Indosinian,possessing a crust-mantle mixing origin.
