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The Awulale Iron Metallogenic Belt (AIMB) located in Central Tianshan is a significant iron ore belt in China. The Beizhan area exhibits extensive volcanic and intrusive rocks that formed during or close to the iron mineralization period. The iron ores in Beizhan are found in Early Carboniferous rhyolite and dacite tuff. The rhyolite is enriched in LILEs and LREEs, depleted in HFSEs, and shows high positive εNd(t) values (+3.0–+4.0). Late Carboniferous intrusive rocks include a granite stock and diabase and diorite dykes. The zircon grains from the granite yield a weighted mean 206Pb/238U age of 311.8 ± 2.6 Ma. The geochemical features of the granite are similar to those of rhyolite, but with pronounced negative anomalies of Eu, Sr, P, and Ti and higher positive εNd(t) values (+4.9–+5.1). The zircons in the diorite dyke yield a weighted mean 206Pb/238U age of 299.2 ± 1.4 Ma. Both the diabase and diorite dykes show an enrichment of LREEs and depletion of HFSEs with high positive εNd(t) values (+3.3–+7.3 and +2.3–+2.6, respectively), although the Eu, Th, and Sr anomalies are more negative in the diorite compared to the diabase. The rhyolite displays high positive εNd(t) values and young Nd model ages (TDM2 = 760–838 Ma) and has Nb/Ta ratios (11.3–12.8) close to that of the continental crust, indicating that it originated from the partial melting of the juvenile lower crust. The granite has similar geochemical characteristics (TDM2 = 656–673 Ma and Nb/Ta ratio = 8.7–10.9) and is also believed to have originated mainly from the partial melting of the juvenile lower crust. The diabase and diorite dykes have low (Tb/Yb)N ratios (<2) and high Ba/Th (31.8–353.2 and 185.3–251.3, respectively) and Sr/Th (113.8–312.9 and 144.7–163.1) ratios, and exhibit a pronounced depletion of HREEs and Y and negative Th anomalies, suggesting that they originated from a spinel-garnet lherzolite mantle source. The Early Carboniferous rhyolite erupted in a continental arc setting, whereas the Late Carboniferous granites, diabase dykes, and diorite dykes formed in an extensional setting associated with the upwelling of the asthenosphere. Therefore, the magmatism and Fe mineralization in the AIMB are correlated with an extensional setting associated with oceanic slab breakoff. [ABSTRACT FROM AUTHOR]

Observational studies and clinical trials have evaluated the associations between vitamin D supplementation and cancer incidence/mortality and obtained mixed results. Previous meta-analyses have also yielded inconsistent conclusions. In this paper, we conduct an updated meta-analysis by including current randomized clinical trials (RCTs) to assess the association between vitamin D supplementation and cancer incidence and mortality. The PubMed, Scopus and Embase databases were systematically searched from their inception to 6 February 2022. Fixed-effects meta-analyses were conducted. Trial sequential analyses were performed using a risk ratio reduction threshold of 10% for cancer incidence and mortality. Twenty-six RCTs were eligible, and pooled results indicated that vitamin D supplementation, compared to placebo with/without calcium, was not associated with a reduction in total cancer incidence (risk ratio: 0.98, 95% CI: 0.94, 1.02; I2 = 0%). In contrast, vitamin D supplementation significantly reduced total cancer mortality (risk ratio: 0.88, 95% CI: 0.8, 0.96; I2 = 0%). Moreover, trial sequential analysis provided reliable evidence that supplementation with vitamin D lowered the relative risk of total cancer mortality by 10%. Our updated meta-analysis suggested that vitamin D supplementation did not reduce total cancer incidence but significantly lowered total cancer mortality. Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2056574. [ABSTRACT FROM AUTHOR]

The Zhibo iron deposit is hosted in Carboniferous submarine volcanic rocks in Western Tianshan, NW China. A series of magnetite‐bearing intermediate‐mafic volcanic rocks are recognized in the periphery of the Zhibo ore district. Most of these volcanic rocks formed at 314 ± 2 Ma, possess tholeiitic–calc‐alkaline affinities, and display remarkable negative Nb, Ta, and Ti anomalies on primitive mantle‐normalized incompatible element diagrams. These features, together with those of their relatively complete rock assemblages and Th/Yb versus Nb/Yb diagrams, are indicative of their formation in an active continental margin arc setting. The wide compositional spectrum of SiO2 values ranging from 47.11 to 62.75 wt.% and lower Mg# values (55–63) of basalts suggest that the Zhibo intermediate‐mafic volcanic rocks may have experienced magmatic differentiation. Their (Th/Ta)PM > 1, (La/Nb)PM > 1, Nb/Ta (11‐16), and Th/Ce (0.06‐0.23) values suggest that the source of these intermediate‐mafic volcanic rocks was significantly contaminated by crustal materials. The magnetites in the iron ore have lower contents of Al, Mn, Ti, and V, indicating that the mineralization of magnetite in the iron ore occurred under lower temperature and higher oxygen fugacity conditions than those in the intermediate‐mafic volcanic rocks. In addition, the magnetites in the Zhibo iron ores have lower contents of compatible elements (e.g., Ti, V, Mn, Co, Cr, and Zn) than those of the magnetite in the intermediate‐mafic volcanic rocks, suggesting that the Zhibo magnetites crystallized from late‐stage, residual iron‐rich magmatic melts/magmatic‐hydrothermal fluids. In addition, the textures of the volcanic rocks suggest that iron have ever enriched in the residual melt during the magmatic stage, and the iron‐rich fragments in andesitic volcaniclastic rocks indicate that the ore‐forming material was a high‐salinity fluid‐bearing iron‐rich melt. In combination of available information, including field observations and geochemical analyses, we interpret that the Zhibo iron deposit is magmatic‐hydrothermal in origin. [ABSTRACT FROM AUTHOR]

The bedded Jingtieshan barite deposit, which occurs in the western part of North Qilian, NW China, is intimately associated with banded iron formation (BIF) and is hosted in weakly metamorphosed Mesoproterozoic clastic–carbonate rocks. Although numerous studies have focused on the BIF, the origin of the barite mineralization is poorly understood. The barite orebody occurs as a lenticular/stratiform unit overlying and locally interlayered with the BIF. In this contribution, we present a comprehensive and integrated study of the geochemistry and S–O–Sr‐isotope characteristics of the Jingtieshan barite deposit, thereby constraining its origin and the depositional conditions in the Mesoproterozoic ocean. The ore is composed of barite, minor carbonate minerals, specularite, and other minerals and is characterized by low Sr concentrations (711–1469 ppm), total rare earth element concentrations (7–28 ppm), and La/Ce values, relative enrichment in light rare earth element, positive Gd anomalies, and elevated Lan/Cen, which indicate that mineralizing fluids were derived from seawater and submarine hydrothermal solutions. Barite separates yield δ34S = 19.5–29.1‰ and δ18O = 12.7–23.6‰, which are consistent with a coeval seawater origin for SO42− modified bacterial sulfate reduction. Moreover, the 87Sr/86Sr values suggest that Sr, as well as Ba, was derived from contemporaneous seawater and hydrothermal solutions, with additional radiogenic Sr derived from late‐stage hydrothermal alteration. The redox‐sensitive trace element ratios of V/(V + Ni), V/(V + Cr), and V/Cr, combined with negative Ce anomalies (0.11–0.82), indicate that the barite formed under oxic marine conditions in a redox stratified ocean. Geological, geochemical, and isotope data support a sedimentary–exhalative origin for the Jingtieshan barite deposit, where barite was deposited under oxic conditions in a shallow marine environment when ascending Ba‐bearing submarine hydrothermal solutions encountered sulfate‐rich seawater. [ABSTRACT FROM AUTHOR]

The Awulale iron metallogenic belt (AIMB) hosts the majority of rich iron ores in Tianshan Orogen and has attracted much attention. However, a hot debate exists about the genesis of these iron deposits. Geochronological data are among the few critical evidences to solve the dispute. This study chooses the Beizhan iron deposit to carry out a geochronological research. The Beizhan magnetite deposit, with total iron ore reserves of 468 Mt at an average grade of 41% TFe, is the largest iron deposit in the AIMB. The orebodies of the Beizhan deposit are hosted in Carboniferous dacite and crystal tuff. Four stages of mineral formation can be recognized: an early skarn mineral stage, followed by the magnetite stage, the sulphide stage, and the carbonate stage in order. Pyrite separated from pyrite-rich ore samples yields an isochron age of 302.5 ± 8.2 Ma. Muscovite separated from muscovite-rich ore samples yields40Ar/39Ar plateau ages of 304.7 ± 1.8 Ma, 304.5 ± 1.9 Ma, 308.1 ± 1.9 Ma, and 307.2 ± 1.8 Ma, and isochron ages of 306.1 ± 3.5Ma, 304.0 ± 3.0Ma, 308.2 ± 3.1Ma, and 308.7 ± 3.1Ma, respectively. These ages are consistent within the error range and are interpreted as the age of the Beizhan iron deposit. The results, combined with the other latest precise dating and geologically inferred ages, demonstrate that the iron deposits in the AIMB were formed in the Late Carboniferous. These iron deposits are considered to be iron skarn or medium–low -temperature hydrothermal origin and have genetic linkages between each other. They may be different mineralizing manifestations proximal to or distal from a pluton. The Late Carboniferous iron ores and the related magmatic rocks in the AIMB were produced when upwelling of the asthenosphere causes the partial melting of various sources and the formation of a narrow linear extension in the upper crust. The upwelling of the asthenosphere may be triggered by the detachment of an orogenic root zone. [ABSTRACT FROM AUTHOR]