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The Shapoling Mo deposit is located in the Xiong'er rock mass of the southern margin of the North China Craton. The deposit is hosted in a contact zone between granite and wallrocks of the Taihua Soupergroup, which is a recently found discovered vein dissemination type deposit in East Qinling. The ore-bodies are associated with quartz veins and controlled by subsidiary faults. The mineralization styles include veinlet and disseminated types. In order to determine the age of the Shapoling Mo deposit, Re-Os isotopic dating of molybdenite was conducted. Six molybdenite samples yielded Re-Os ages ranging from 158.3±1.5 Ma to 160.7±1.2 Ma, with a weighted mean age of 160±1 Ma (2σ, MSWD=2.1). The Re-Os age shows that the Mo mineralization occurred during the late Jurassic, earlier than the formation of Huashan rock mass (about 30 Ma). In addition, one molybdenite sample in Huashan rock mass yielded a Re-Os age of 130.5±1.0 Ma, which is in accordance with the age of the Huashan pluton and molybdenite age (125.4-129.4 Ma) reported by a previous study. In conclusion, the Shapoling deposit contains two episodes of Mo mineralization from the early Cretaceous and late Jurassic periods. Combining this with geological characteristics and tectonic-metallogenic evolution, it is suggested that Huashan rock mass, granite porphyry, and related hydrothermal deposits in the Xiong'er terrain are the products of extrusion to extension transition during continent-continent collision in the Qinling orogenic belt.

The Zhifang Mo deposit is located in the northeastern Qinling Orogen along the southern margin of the North China Craton. The deposit represents a quartz-vein system hosted in the Mesoproterozoic Xiong'er Group volcanic rocks. We identify three hydrothermal stages (early, middle and late), characterized by veinlets of quartz–pyrite, quartz–molybdenite–pyrite–chalcopyrite–galena–sphalerite, and quartz–carbonate assemblages, respectively. Five molybdenite samples from the Zhifang deposit yield Re–Os ages ranging from 241.2 ± 1.6 Ma to 247.4 ± 2.5 Ma, with an isochron age of 246.0 ± 5.2 Ma (2σ, MSWD = 7.4), and a weighted mean age of 243.8 ± 2.8 Ma (2σ, MSWD = 5.5). The Re–Os age shows that the Mo mineralization occurred during the Indosinian Orogeny, and suggests that the mineralization is unrelated to the Yanshanian magmatism or the Paleo-Mesoproterozoic volcanic–hydrothermal event. This study also reports a new Sr–Nd–Pb isotope dataset from ore sulfides in an attempt to constrain the source of the ore-forming fluids. Ten sulfide samples from middle stage of the Zhifang Mo deposit yield I Sr (t) ratios of 0.710286–0.711943, with an average of 0.711004; ε Nd (t) values between − 19.5 and − 14.8, with an average of − 16.7; and ( 206 Pb/ 204 Pb) i , ( 207 Pb/ 204 Pb) i and ( 208 Pb/ 204 Pb) i ratios of 17.126–17.535, 15.374–15.466 and 37.485–37.848, with averages of 17.380, 15.410 and 37.631, respectively. One pyrite from the early stage yield I Sr (t) of 0.722711–0.722855, with an average of 0.722783, which is higher than those of the middle stage sulfides and suggests equilibration with wallrocks. The ε Nd (t) values are in the range of − 17.3 to − 16.6 with a mean at − 17.0; and ( 206 Pb/ 204 Pb) i , ( 207 Pb/ 204 Pb) i and ( 208 Pb/ 204 Pb) i ratios are 17.386, 15.405 and 37.622, respectively. The ore sulfides show higher Pb-isotope ratios, higher ε Nd (t) and lower I Sr (t) values than the host rocks. The results suggest that the ore-forming fluids had lower I Sr (t), and higher ε Nd (t) values than the ore sulfides, and were possibly sourced from the Dengfeng Complex. The southward subduction of the North China Craton beneath the Huaxiong Block during the Triassic was possibly responsible for the formation of the Waifangshan orogenic Mo system. [ABSTRACT FROM AUTHOR]

This study first described three-dimension images of a fluid inclusion hosted within sphalerite based on transmission nano X-ray tomography. It shows multiple shapes of the fluid inclusion viewed from different angles. This fluid inclusion contains both vapor and liquid phases, with irregular, asymmetry shape and concaved boundary. A reconstructed three-dimension animation viewer makes the shapes clearly. This study offers a technique to penetrate inside the fluid inclusion and calculate the volume of the single fluid inclusion based on the 3D images and animation, which can be applied for the future single fluid inclusion compositional studies. [ABSTRACT FROM AUTHOR]

The Shagou deposit, located in the eastern Qinling orogenic belt, central China and hosted by the Taihua Supergroup, is a large-sized Ag–Pb–Zn deposit and has proven reserves of 1.54million tons of ore with grades of 767g/t Ag, 13.24% Pb and 4.31% Zn. The ore-forming fluids have been previously interpreted as products of direct exsolution of a crystallizing magma or sudden decompression of the fluid exsolved from magma, defining the Shagou deposit as an intrusion-related system. In this study, the Shagou deposit has been identified as an orogenic type mineralization system. The hydrothermal ore-forming process can be divided into the early quartz–pyrite, middle quartz–polymetallic sulfides and late quartz–carbonate stages. Four types of fluid inclusions in quartz can be distinguished between PC, C, W and PW types. The early and middle stage quartz contains the PC, C and W type fluid inclusions, while only W and PW type fluid inclusions can be observed in the late stage quartz. In the early stage, the W type fluid inclusions homogenized at 173–369°C (concentrating at 200–240°C), with salinities ranging from 5.4 to 8.3wt.% NaCl equiv. But in the middle stage, the C and W type fluid inclusions homogenized at 112–313°C (concentrating at 180–220°C), with salinities ranging from 0.7 to 13.6wt.% NaCl equiv. In the late stage, the W type fluid inclusions homogenized at 108–253°C (concentrating at 160–200°C), with salinities ranging from 2.1 to 8.1wt.% NaCl equiv. The fluids may have experienced a boiling process or fluid mixing in the middle stage. The estimated trapping pressures of fluid inclusions in the middle stage ranged from 33 to 211MPa, corresponding to a mineralization depth from 3.3 to 7.7km. For the early stage fluids, the calculated δ18OH2O and δDH2O values are 7.5–9.1‰, −96.2 to −110.5‰, respectively. For the middle stage fluids, these two values are 1.5–5.3‰, −75.6 to −110.7‰ but change to 1.0‰ and −87‰ for the late stage, suggesting an evolution from metamorphic to meteoric in origin. In general, the Shagou Ag–Pb–Zn deposit is similar in many respects to typical orogenic type mineralization systems. [ABSTRACT FROM AUTHOR]

The Dashui porphyry granitoids in the western Qinling Orogen are spatially associated with the Dashui gold deposit, but their ages and tectonic setting have not been well defined yet in previous studies. This paper reports the results and understandings obtained from our original study in geochronology and isotope and element geochemistry. SHRIMP zircon U-Pb dating yielded ages of 213.7 ± 2.7 Ma for granitic stock and 215.1 ± 2.5 and 210.2 ± 1.6 Ma for granitic dikes. The granitoids are characterized by high LREE but low HREE and HFSE. They have (87Sr/86Sr) i ratios of 0.706 to 0.709 and εNd(t) values of −5.3 to −7.6. The majority of zircons in the Dashui granitoids have εHf(t) values ranging from −6.2 to 6.7 and TDM2(Hf) ages from 743 to 1464 Ma. The isotope signatures, together with La/Y and Mg# values, show that the magmas are mainly sourced from partial melting of a subducted slab, and possibly assimilated immature sediments during upward migration. Thus, the Dashui granitoids most likely formed in a volcanic arc where supra-subduction zone melts assimilated lower crustal material no later than 215 Ma. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The East Qinling region in central China, hosting several tens of Mesozoic magmatic-hydrothermal Mo deposits, is one of the largest molybdenum belts in the world. The Zhifang Mo deposit is hosted in volcanic rocks of the Xiong'er Group in the Waifangshan area, Qinling Orogen. Previous studies variously correlated the mineralization in this deposit with Yanshanian magmatism or Palaeo-Mesoproterozoic volcanic-hydrothermal events. The orebodies are associated with quartz veins and controlled by subsidiary faults of the Machaoying Fault. The ore-forming process can be divided into the early, middle and late stages and is characterized by quartz-pyrite, quartz-polymetallic sulphide and quartz-carbonate veins, respectively. The early-stage quartz is structurally deformed, suggesting a compressional tectonic regime; the middle-stage sulphides fill the fractures of the early-stage assemblages and show no deformation, suggesting a tensional setting; the late-stage veins mostly infill the open-space fissures. Three types of fluid inclusions (FIs) are identified at the Zhifang deposit: H2O-NaCl (W-type), CO2-rich (C-type) and daughter mineral-bearing inclusions (S-type). Fluid inclusions of early-stage quartz homogenize between 380 and 470 °C, with salinities ranging from 0.4 to 9.6 wt.% NaCl equiv., whereas the late-stage calcite contains only the W-type FIs with homogenization temperatures of lower than 240 °C, and salinities of 0.4-8.7 wt.% NaCl equiv. This indicates that the ore fluid system evolved from CO2-rich, probably metamorphic hydrothermal to CO2-poor, meteoric fluid. All three types of FIs can be observed in the middle-stage quartz, and even in the microscopic domain of a crystal, suggesting that this heterogeneous association was trapped from a boiling fluid system. These FIs homogenized at temperatures ranging from 250 to 360 °C and display two salinity clusters of <18.5 and 29.1-29.9 wt.% NaCl equiv. These results suggest that metal precipitation resulted from fluid boiling. The estimated trapping pressures of FIs range from 101 to 285 MPa, suggesting an alternating lithostatic-hydrostatic fluid system, which was controlled by a fault-valve at the depth of 10 km. The δ34S values of ore minerals from the Zhifang Mo deposit show a range between −11.8‰ and 6.0‰, with a bimodal distribution. The early-stage pyrite has a positive δ34S value of 6.0‰ that is similar to the host rocks of the Xiong'er Group and the Taihua Supergroup, suggesting that the wall rocks contributed much of the sulphur to the early-stage pyrite during fluid-rock interaction. However, the δ34S values of the middle-stage sulphides have negative mean and restricted range from −11.8‰ to −4.5‰. The widespread rutile grains coexisting with molybdenite in the middle-stage correlate the negative δ34S values with relatively oxidized fluids. We consider phase separation as an efficient mechanism for ore-fluid oxidation and molybdenum deposition based on fluid inclusions and sulphur isotope data. Geological, fluid inclusion and sulphur isotope data of the Zhifang Mo deposit suggest that the Mo mineralization is unrelated to the Yanshanian magmatism or the Palaeo-Mesoproterozoic volcanic-hydrothermal event. Here we propose that the Zhifang Mo deposit may be considered as an orogenic mineral system, with its formation in an active continental margin related to the northward subduction of the Mian-Lue oceanic plate during the Triassic. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The East Qinling Molybdenum Belt (EQMB), central China, hosting tens of Mesozoic magmatic hydrothermal Mo deposits, is one of the largest molybdenum belts in the world. Recently, a new type of Mo mineralization characterized by molybdenite-fluorite veins was discovered with ongoing prospecting at the Tumen area in the Huaxiong block, representing the southernmost tectonic unit of the North China Craton. The molybdenite-fluorite veins occur in faults or ductile shear zones cross-cutting the Neoproterozoic Luanchuan Group. At the Tumen deposit, CO2-rich, aqueous and daughter mineral-bearing fluid inclusions are observed in fluorite. These fluid inclusions resemble those reported from magmatic hydrothermal Mo systems formed in intracontinental tectonic settings and yield homogenization temperatures up to 450 °C, with salinities up to 39.8 wt.% NaCl equiv, suggesting that the mineralization resulted from a magmatic fluid system. Seven molybdenite analyses from the molybdenite-fluorite veins yield Re-Os isotope ages ranging from 845.8 ± 7.3 to 965.3 ± 7.2 Ma, with an isochron age of 847.4 ± 7.3 Ma (2 σ, MSWD = 23), marking the timing of mineralization as Neoproterozoic. These ages are broadly comparable with the 844.3 ± 1.6 Ma age reported from the Shuangshan syenite located near the mining area, and the ca. 830 Ma gabbros occurring within the same tectonic unit, indicating that the deposit was possibly related to Neoproterozoic rifting at the southern margin of the North China Craton. The age data correspond to the transition from the culmination of the assembly of the Neoproterozoic supercontinent Rodinia to the beginning of its break-up. Our results provide new insights into the regional tectonics and show that the Mo mineralization is not related to the much younger Mesozoic Yanshanian magmatism as considered in previous studies. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Waifangshan Mo-quartz vein cluster occurs at the northernmost margin of the Qinling Orogen. The orebodies occur as quartz veins and are controlled by low-angle faults. We identify three hydrothermal stages, characterized by veinlets of quartz–pyrite, quartz–molybdenite–pyrite–chalcopyrite–galena–sphalerite, and quartz–carbonate assemblages, respectively. The early-stage quartz veins were structurally-deformed, brecciated, and filled by non-deformed middle- or late-stage veinlets, suggesting that the mineralization is associated with a tectonic transition from compression to extension. Five molybdenite separates from the Zhifang Mo deposit yield individual Re–Os ages from 241.2 ± 1.6 to 247.4 ± 2.5 Ma, with a weighted mean age of 243.8 ± 2.8 Ma. Individual Re–Os isotope ages of four molybdenite samples from the Badaogou Mo deposit range from 238.9 ± 2.1 to 255.8 ± 2.2 Ma, with a weighted mean age of 246 ± 10 Ma. Four analyses of molybdenite separates from the Xiangchungou Mo deposit yield individual Re–Os isotope ages of 243.8 ± 8.8 to 247.7 ± 4.4 Ma, with a weighted mean age of 246.0 ± 1.1 Ma. All of these data yield a weighted mean age of 241.9 ± 1.9 Ma, coeval with the accretionary orogeny. We thus conclude that the Waifangshan Mo-quartz veins formed during a transition from continental arc to back-arc setting. The Waifangshan Mo-quartz veins share similar geological, geochemical and geochronological features with the orogenic-type systems. We propose that the Waifangshan Mo-quartz veins are an orogenic-type Mo mineralization, and possibly represent the deepest member in the crustal continuum model of the orogenic-type mineral systems. The molybdenite samples from the Mo-quartz veins in the Waifangshan area have low Re contents (1.457 to 39.16 ppm), suggesting a continental crust-dominated source. [ABSTRACT FROM AUTHOR]

Introduction: Different results have been achieved in the evaluation of antiparasitic drug activity in Mongolian jirds, hamsters, and BALB/c mice infected with Babesia microti. The aims of the present study were to find a preferable method for drug screening and to re-evaluate the activity of several drugs against B. microti., Methodology: The activity of 19 drugs on B. microti-infected BALB/c mice was evaluated. The study was built on Peters' four-day suppressive test, and the pathogenicity of the blood from the treated mice was also used as indicator., Results: The results showed that 15 of the 19 drugs had little or no in vivo effect against B. microti. The inhibitory rates of atovaquone and azithromycin were high at all doses, but the microscopy-negative blood of recovered mice was still infectious. Similar to robenidine hydrochloride at 25 and 50 mg/kg, primaquine at 100 mg/kg had a 100% inhibitory rate. Robenidine hydrochloride achieved a 100% inhibitory rate at 100 mg/kg, and the blood of recovered mice did not result in parasitemia in subpassage experiments. Parasite-negative blood from mice treated with antimalarial drugs (clinically used for babesiosis) still caused parasitemia in subpassage experiments. This suggests that these drugs cannot eradicate the parasites., Conclusions: Peters' four-day suppressive test and the pathogenicity of the blood from the treated mice are suitable methods for preliminary investigating possible drugs against B. microti. Considering that robenidine hydrochloride achieved the best activity against B. microti in BALB/c mice in our study, further studies are needed.