The development of uranium mines has been necessary to obtain abundant and scarce uranium resources, but they also bring inevitable radioactive contamination to the surrounding soil, rivers and lakes. This paper explores the sensitivity of Cypridopsis vidua to the radioactive element uranium and the heavy elements cadmium and copper with single and combined acute toxicity experiments and combined toxicity model predictions. The results from the single toxicity experiments showed that the degree of toxic effects was cadmium > copper > uranium. The combined toxicity experiments showed that the compound toxicity of U-Cd and U-Cu was higher than the weakest component and lower than the strongest component, whereas the compound toxicity of Cd-Cu was higher than either of its components. When the overall proportion of a more toxic metal was increased, its mixed toxicity also increased, and vice versa. Combined toxicity predictions showed that the U-Cd combination was best described by the concentration additive (CA) model, the independent action (IA) model was more applicable to the Cd-Cu combination, and the most applicable model for the U-Cu combination changed depending on the concentration gradient. The acute toxicity data from this study provide a reference for the development of wastewater discharge standards for uranium mines, enriches the data related to the toxicity of uranium for ostracods and deepens the understanding of the threat of uranium pollution to aquatic ecosystems.

The Jilinbaolige Pb-Zn-Ag polymetallic deposit is located in the eastern part of Inner Mongolia and in the central-southern part of the Great Xing’an Range, in which several large-sized Pb-Zn-Ag deposits have been found. The Jilinbaolige deposit, which occurs mainly at the contact zone between Yanshanian granite intrusion and sedimentary strata, shows strong NE-to-NNE structural control. The deposit includes three ore-forming stages: (1) the arsenopyrite–pyrite–chalcopyrite–sphalerite stage, (2) the galena–sphalerite–quartz stage, and (3) the pyrite–calcite–quartz stage. In this study, we present a systematic study on the mineralogical and geochemical characteristics (including major elements, S isotopes, and Pb isotopes) of the main sulfide ore minerals in the Jilinbaolige Pb-Zn-Ag deposit in order to evaluate the metallogenic environment, ore-forming material source, and genesis of this polymetallic deposit. The sulfide typomorphic characteristics, ore fabric, and thermometry suggest that the genesis of sulfides in the deposit is closely related to magmatic-hydrothermal activity. The early stage of mineralization might have evolved from a high-temperature hydrothermal environment. The sulfur isotopic results show that the δ³⁴S values in the Jilinbaolige deposit range from 2.3‰ to 6.1‰, with an average value of 3.98‰, indicating that the sulfur originated from magmas with both mantle and crustal components. The Pb isotopic compositions (²⁰⁶Pb/²⁰⁴Pb = 18.214–18.330, ²⁰⁷Pb/²⁰⁴Pb = 15.478–15.615, ²⁰⁸Pb/²⁰⁴Pb = 37.957–38.292, μ = 9.24–9.50, ω = 34.49–36.49) of the sulfide ores suggest that that the lead is of crust-mantle mixed origin. The comparison between the S and Pb isotopic compositions of the Jilinbaolige deposit and the polymetallic deposits from the central-southern parts of the Great Xing’an Range suggests that these deposits have a similar metallogenic source, which is closely related to the Yanshanian granite and medium-temperature hydrothermal fluids. These ore-bearing hydrothermal fluids that evolved from deep magmatic sources migrated along the contact and fracture zones and during the subsequent gradual decrease in temperature, and the metallogenic components were deposited in the relatively open fracture and fissure space. Our results provide insights for further mineral prospecting in the south-central part of the Great Xing’an Range.

Controversy over the geodynamic interpretation of the early Paleozoic granites in the South China Block constrains understanding of tectonic–magmatic evolution. In this paper, we present zircon U-Pb age, Hf isotope, and major and trace element data of the early Paleozoic granites in the Jilongjie region, south-central Hunan Province. A sample that yielded a weighted average ²⁰⁶Pb/²³⁸U age of 425 ± 3 Ma falls into the post-collisional granite field in the classification discriminant of magmatic rocks. Geochemical features indicate that the Jilongjie pluton is a shoshonitic metaluminous rock. The Jilongjie pluton’s chondrite-normalized rare earth element patterns exhibit a slight enrichment of light rare earth elements (LREEs) relative to heavy rare earth elements (HREEs) with (La/Yb)_N ratios of 15.1–23.7 and weak Eu anomalies (Eu/Eu* = 0.68–0.78). Zircon Hf isotope results show ε_Hf(t) ranging from −9.94 to −0.69. Jilongjie granite’s parent magma originated from a mixing of crust-derived felsic and mantle-derived mafic magmas, which then underwent fractional crystallization during its ascent. Jilongjie granite was generated through a post-collisional extensional setting associated with delamination of the thickened lithosphere.

Clarify the petrogenesis and dynamics mechanism of Triassic magmatic rock in the South China Block (SCB) is crucial for understanding the geological evolution and mineralization of South China. A series of metal deposits (including lead, zinc, tungsten, tin, uranium, etc.) have been discovered inside and near the Yajiangqiao plutonic rock, which is important ore-forming granite in the eastern Hunan region. However, its petrogenesis and tectonic setting are still controversial. Here, we present new zircon U–Pb ages and trace elements, and whole-rock major- and trace- element compositions, and in-situ Hf isotope data obtained from the Yajiangqiao granites in central SCB. LA-ICP-MS zircon U–Pb dating reveals that the granites were emplaced in the late Triassic (227 ± 2 and 226 ± 2 Ma). The geochemical characteristics of zircon and whole-rock trace elements indicate that the Yajiangqiao granites are S-type granite, which originated from the partial melting of crustal material mainly composed of metapelitic sources, with a small amount of mantle-derived material added and undergoing strong fractional crystallization. In combination with regional geological data, we suggest that the late Triassic granites in the central SCB likely were the response to the underplating of mantle-derived magmas in a post-collision setting.