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Late Ordovician–Early Silurian intermediate igneous rocks have been detected in the Dunhuang Block, NW China. These igneous rocks help to constrain the tectonic evolution of the Dunhuang Block and the southern Central Asian Orogenic Belt in the early Paleozoic. We carried out zircon U–Pb dating, whole-rock geochemistry and zircon Hf isotope analyses for the early Paleozoic gneissic diorites from the Sanweishan and northern Huangshuihou areas in the Dunhuang Block. The zircon U–Pb geochronology shows that the emplacement ages of the gneissic dioritic rocks were c. 443–440 Ma. The dioritic rocks show varying SiO 2 (48.1–63.1 wt%) and MgO (1.87–3.52 wt%) contents, with high Mg# (46–52) values and negative Eu anomalies (Eu/Eu* = 0.62–0.94). Zircons in the gneissic diorites from the northern Huangshuigou and Sanweishan areas yield variable ε Hf ( t ) values of −4.4 to +10.4 and −8.6 to −6.2, respectively, coupled with low Rb/Sr (0.04–0.34), Rb/Ba (0.06–0.31) and Al 2 O 3 /(MgO + FeO T ) (0.72–1.47) ratios, indicating that they were predominately generated by disequilibrium melting of the juvenile crust and mixed with ancient crustal and minor mantle melts. In conjunction with previously published data, we propose that the early Paleozoic gneissic dioritic rocks were formed in a continental margin arc setting related to the southward subduction of the Palaeo-Asian Ocean. Our findings suggest that the Dunhuang Block was modified and reactivated by the Paleozoic orogenic events related to the evolution of the Palaeo-Asian Ocean, resulting in extensive Paleozoic magmatism–metamorphism over the whole Dunhuang area. Supplementary material: Analytical methods, U-Pb geochronological data, zircon trace element data, zircon Lu-Hf isotopic compositions, and geochemical data for analysed samples, and additional figures are available at https://doi.org/10.6084/m9.figshare.c.6174601

Groundwater in confined aquifers is the preferred water resource worldwide, and its hydrochemical quality is the premise for sustainable development. A systematic hydrogeochemical research was conducted to get insight into the hydrochemical characteristics, genesis, and potential health threats of confined groundwater, based on analytical data of 45 groundwater samples collected from the urban area of Hengshui, Central North China Plain (NCP). The results showed most groundwater had desirable hydrochemical quality with a nearly neutral to slightly alkaline nature and dominantly soft-fresh Cl-Na face. Solute chemistry was governed by rock-water interaction including minerals dissolution and ion exchange, but out of the anthropogenic influences. All nitrogen pollutants and Zn were within the desirable limit, while F−, Mn, and Fe were beyond the desirable limit recommended by WHO in 28.9%, 15.6%, and 68.9% of samples. Overall chronic health risk from these toxic elements was identified in terms of various populations and mainly contributed by F−. Infants were more prone to the health risks of aqueous pollutants. Differential water supplies based on hydrochemical quality are recommended, and water improvement measures are suggested to be conducted aiming at the harmful fluoride in confined groundwater. The present research could provide valuable references for the health sustainability of confined groundwater utilization in sedimentary plains like NCP worldwide.

The present study was conducted to appraise the suitability and human health risk of groundwater in a rapid urbanization area of North China. Groundwater samples were collected from phreatic and confined aquifers throughout the study area during pre- and post-monsoon seasons. Results show groundwater, regardless the depth, is slightly alkaline in nature and relatively fresh with the total dissolved solids within 600 mg/L. The hydrochemical facies of phreatic and confined groundwater are dominantly HCO3-Ca·Mg, followed by HCO3-Na. Groundwater in the study area, regardless the depth, is suitable for irrigation with almost no salinity and sodium hazards if proper drainage measures are undertaken. The entropy weight water quality index evaluating results show all phreatic and confined groundwater is suitable for drinking purposes. The overall potential non-carcinogenic risk posed by nitrogen (NO3-N, NH4-N) and heavy metals (As, Zn, Fe, Mn) through drinking water ingestion exists in the southwestern area and a small local area in the central study area, and is higher for children. Special attention should be paid to the arsenic because its hazard quotient was very high in some local areas. This study will benefit the protection and utilization of groundwater in near-suburb areas around the world.

Geostatistics was used in a typical alluvial fan to reveal its applicability to spatial distribution analysis and controlling mechanisms of groundwater chemistry. Normal distribution test and optimal geostatistical interpolation models for various groundwater quality indicators were discussed in this study. The optimal variogram model of each indicator was determined using prediction error analysis. The influences of human activities and structural factors on the groundwater chemistry were also determined by variability intensity and the sill ratio. The results showed that nitrate content can be served as groundwater quality indicator, which was most sensitive to human activities. The nitrate concentration of both shallow and deep groundwater showed a decreasing trend from the northwest to the southeast. In addition, the spatial distribution of groundwater nitrate was associated with the land-use type and the lithological properties of aquifer. Rapid urbanization in the northwestern part intensified groundwater extraction and aggravated the pollutant input. The central area showed little increase in nitrate content in the shallow and deep groundwater, and the effect of lateral recharge from the upstream water on the deep groundwater in the central area was greater than that of the vertical recharge from shallow groundwater. The present study suggests that geostatistics is helpful for analyzing the spatial distribution and distinguishing the influences of anthropogenic and natural factors on groundwater chemistry.

The Early Cretaceous (ca. 128 Ma) Shapoling vein-type molybdenum (Mo) mineralization, associated with the Huashan intrusion is a newly discovered deposit in the Xiong'ershan district, East Qinling, China where pyrite is a ubiquitous mineral phase. Here we present results from an integrated study on the texture, in situ trace element chemistry from laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and sulfur isotopic composition using secondary-ion mass spectrometry (SIMS), with a view to understand the geochemical variation, genesis of Mo mineralization and ore-forming process. The distinct textural patterns as revealed by petrographic observations suggest three types of pyrites: Py1 is composed of coarse-grained euhedral pyrite in the wall rock and early barren quartz vein at Stage I, Py2 is represented by subhedral-anhedral grains coexisting with molybdenite in quartz veins at Stage II, and Py3 forms irregular interstitial grains in the quartz + K-feldspar + molybdenite dominated veins at Stage III. The Mo enrichment mainly occurred in Py3 (with Co/Ni ratios >1 and δ34S values mainly

Assessments for groundwater quality and potential health risk are significant for better utilization and exploitation. In the present study, seventy groundwater samples were collected from domestic tube wells and public water-supply wells in the Nanchong area, southwestern China. The integration of statistical analysis, ion correlation, geomodelling analysis, entropy water quality index and health risks assessment were compiled in this study. Statistical analysis indicated the cations followed the concentration order as Ca2+ > Na+ > Mg2+ > K+, while anions' concentrations were HCO3- > SO42- > Cl- > NO3- > F- based on Box and Whisker plot. Piper triangle diagram proposed the hydrochemical type was characterized as Ca-HCO3. Correlations of ions and geomodelling revealed the concentrations of major ions were mainly determined by calcite dissolution and ion exchange process and NO3- concentrations were controlled by agriculture activities. Entropy water quality index computation demonstrated that 96% of groundwater samples possessed the EWQI values of 29-95, and thus were suitable for drinking purpose. The HITotal values for 66% groundwater samples exceeded the acceptable limit for non-carcinogenic risk (HI =1) for infants, followed by 41% for children, 37% for adult males, and 30% for adult females. The non-carcinogenic human health risk of different population groups followed the order of infants > children > adult males > adult females. In future, targeted measures for human health risks of NO3- will focus on the improvements for agricultural activities, including reducing the use of nitrogenous fertilizer, changing irrigation pattern, etc. Our study provides the vital knowledge for groundwater management in the Nanchong and development of the Cheng -Yu Economic Circle.

Groundwater is an essential resource for sustainable development, whose quality is significant for human health. In the present study, twenty-eight groundwater samples were collected from domestic tube wells and public water supply wells in the Suining area, southwestern China. The integration of statistical analysis, correlations of ions, geomodelling, and entropy-weighted water quality index (EWQI) was carried out to clarify the hydrochemistry and groundwater quality in the study area. By the statistical analysis, the cations followed the concentration order as Ca2+> Na+> Mg2+> K+, while anions’ concentrations were HCO3− > SO42− > Cl− > NO3− > F−. Piper trilinear diagram showed the hydrochemical type was characterized as Ca-HCO3. Correlations of ions and geomodelling revealed the concentrations of major ions were mainly determined by carbonate dissolution and ion exchange process, and NO3− concentrations were controlled by agriculture activities. EWQI computation demonstrated that most of the groundwater samples possessed EWQI values higher than 100. Therefore, groundwater quality is lower than the permissible limit of the World Health Organization (WHO), suitable for drinking purposes in the Suining area. Our study provides vital knowledge for groundwater management in the Suining and other similar areas.

Like genes and proteins, cells can use biochemical networks to sense and process information. The differentiation of the cell state in colonic crypts forms a typical unidirectional phenotypic transitional cascade, in which stem cells differentiate into the transit-amplifying cells (TACs), and TACs continue to differentiate into fully differentiated cells. In order to quantitatively describe the relationship between the noise of each compartment and the amplification of signals, the gain factor is introduced, and the gain-fluctuation relation is obtained by using the linear noise approximation of the master equation. Through the simulation of these theoretical formulas, the characters of noise propagation and amplification are studied. It is found that the transmitted noise is an important part of the total noise in each downstream cell. Therefore, a small number of downstream cells can only cause its small inherent noise, but the total noise may be very large due to the transmitted noise. The influence of the transmitted noise may be the indirect cause of colon cancer. In addition, the total noise of the downstream cells always has a minimum value. As long as a reasonable value of the gain factor is selected, the number of cells in colonic crypts will be controlled within the normal range. This may be a good method to intervene the uncontrollable growth of tumor cells and effectively control the deterioration of colon cancer.

Late Mesozoic granites are extensively distributed in the Luanchuan district of eastern Qinling and can be divided into two types: Late Jurassic to Early Cretaceous granites (ore-related plutons) and Late Cretaceous granites (Laojunshan batholith). This study presents new geochemical and zircon U-Pb-Hf isotopic data from the Shibaogou and Yuku plutons to provide robust constraints on the petrogenesis and tectonic significance of the late Mesozoic granites in the Luanchuan district. Zircon U-Pb dating results yielded weighted mean 206Pb/238U ages of 149.1 ± 0.8 Ma and 150.5 ± 0.8 Ma, which were interpreted as the crystallization ages of the Shibaogou and Yuku plutons, respectively. We propose that the late Mesozoic granites contain high concentrations of SiO2 and alkali elements (Na2O + K2O) and feature metaluminous to weakly peraluminous characteristics. Enrichment in light rare earth elements and large ion lithophile elements and depletion in high field strength elements are observed. Mineralogical and geochemical evidence reveal that the late Mesozoic granites are highly fractionated I-type granites with fractional crystallization of feldspar, plagioclase and accessory minerals (e.g., apatite and titanite or magnetite). Based on the Hf composition, we suggest that the parental magmas of the ore-related plutons were derived from remelting of the Taihua and Xiong’er groups with minor contributions of mantle-derived materials and that the Laojunshan batholith was generated by the hybridization of ancient crust- (Kuanping group) and mantle-derived components. Collectively, the above arguments indicates a tectonic transition from compression to post-collisional extension during the late Mesozoic, that was likely triggered by the continental collision of the North China Block and the Yangtze Block, which generated numerous contemporaneous granites and Mo-W-Pb-Zn-Ag-Au poly-metallic deposits.

The Upper Triassic Langjiexue Group, which lies immediately south of the Yarlung-Tsangpo Suture Zone in the Shannan area of southeastern Tibet, represents an important part of the Tethyan Himalayan...

Recently identified Early Jurassic, Early Cretaceous, and Late Cretaceous granites of the Tengchong terrane, SW China, help to refine our understanding of the Mesozoic tectonic-magmatic evolutionar...

The Xing’an–Mongolia orogenic belt is located in the southeastern segment of the Central Asian Orogenic Belt. Its tectonic evolution, especially during the Late Palaeozoic to Early Mesozoic, remains controversial. Here, we report new zircon U–Pb dates, whole-rock geochemistry, and Hf isotopes of representative samples from four plutons in the Linxi area of Northeast China to provide new constraints on this issue. Zircon U–Pb dating indicates that the intrusions were emplaced in two stages: (1) Late Permian to Early Triassic (the Banshifangzi and Xinangou plutons (252 ± 3)–(246.3 ± 3.3) Ma); and (2) Late Triassic (the Baoshan and Hada plutons (220.8 ± 2.7)–(211.4 ± 2.6) Ma). Their positive εHf(t) values (6.6–14.1), coupled with their geochemical characteristics, suggest that the provenance of investigated granitoids were most likely to be dominated by juvenile crustal materials. Based on these new data and previous studies, we propose three stages of tectonic evolution during the Late Palaeozoic–Early Mesozoic in the XMOB: (1) Late Carboniferous–Early Permian (330–270 Ma): double-sided subduction of the Palaeo-Asian Ocean; (2) Middle Permian–Middle Triassic (270–237 Ma): the closure of the Palaeo-Asian Ocean and subsequent continent–continent collision between the North China Craton and the South Mongolia Terrane; and (3) Late Triassic (237–211 Ma): post-collisional extension.

New data from mineralogy, geochemistry, zircon U–Pb dating, and Hf isotopes have revealed Late Cretaceous to Eocene magmatic intrusions in the Tengchong terrane and constrained the origin, tectonic setting, and characteristics of tin-bearing and barren granitoids. We divide the studied granitoids into two groups: (a) the Late Cretaceous Zhinaxiang (70 Ma) and Early Paleocene Dazhupeng (65 Ma) S-type barren granites and (b) the Eocene Lailishan A2-type tin-bearing granite (50 Ma). All these granitoids display Si- and K-rich and calc-alkaline characteristics and have similar chondrite-normalized rare earth element patterns. However, geochemical differences do exist between the two groups of granites. The Zhinaxiang and Dazhupeng S-type granites are slightly peraluminous, enriched in large-ion lithophile elements (e.g., Rb and K), and depleted in high-field-strength elements (e.g., Nb, Ta, Zr, and Hf), whereas the Lailishan A2-type granite has higher TFe2O3, high-field-strength element content, and Ga/Al ratios. The geochemical and Hf isotopic data indicate that the granites in this study were generated by partial melting of Paleoproterozoic metasedimentary rocks. Due to the subduction of the Neo-Tethyan Ocean beneath the Eurasian plate, the Zhinaxiang and Dazhupeng S-type granites were formed in a thickened-crustal environment, whereas the Lailishan A2-type granite was emplaced in a post-collisional extensional setting attributed to slab break-off. By comparison between tin-bearing and barren granites, we propose that the Sn mineralization could be related to relatively high-temperature and low-pressure crystallization conditions.

The Late Mesozoic (i.e. 150–120 Ma) marks one of the most active periods of magmatism in the Southern Great Xing'an Range (SGXR), associated with large-scale mineralization. Here we investigate the large Shuitou fluorite deposit located within the SGXR mineralized belt. The ore bodies strike nearly NS and discontinuously extend for 10 km long. Zircon U–Pb dating of the associated intrusion (the Herimu Tai granite) in the southern part of the area yields an emplacement age of 136.9 ± 1.7 Ma whereas Sm–Nd isotopic data on the fluorite ore yield an isochron age of 132 ± 11 Ma. Fluid inclusions in the fluorite show low homogenization temperatures (140–220 °C), salinities (0.27 wt% NaCl eqv – 2.8 wt% NaCl eqv) and densities (0.86–0.891 g/cm3). The inclusions are mainly composed of H2O, along with minor C3H6 and other organic components. The associated calcite has δ13CV-PDB varying from −7.1‰ to −6.3‰ (average −6.73‰) and δ18OV-SMOW from −2.8‰ to −0.7‰. The field, petrologic and isotopic data from our study leads to the following salient findings. 1) The major minerals in the ore deposit include fluorite, quartz and calcite, which are of hydrothermal origin and have a uniform source and therefore the ore deposit is considered to be of hydrothermal vein-type. 2) The ore-forming fluids can be mainly attributed to NaCl–H2O system with moderate to low temperature, low salinity and low density. There is no evidence for post-magmatic hydrothermal fluid. The ore-forming fluid shows a meteoric water source, with water-rock reaction as the main mechanism for fluorite precipitation. 3) The deposit was formed in an extensional setting within the Central Asian Orogenic Belt and is closely associated with the late Jurassic to early Cretaceous polymetallic events. The nearly synchronous magmatic events in the study area suggest that these might have provided the heat source for fluorite mineralization.

The Lailishan deposit is an important tin deposit that is genetically associated with an Early Eocene biotite granite in the western Yunnan metallogenic belt in the Sanjiang region, SW China. This study reports new zircon U–Pb ages and Hf isotopic data, whole–rock elements, mica Ar–Ar age and C–H–O–S–Pb isotope for the Lailishan Sn deposit. The mineralization–related biotite granite crystallized during the Early Eocene (50.5 Ma), with its zircon eHf(t) values ranging from −11.5 to −7.6 and two–stage Hf model ages (T DM2 ) ranging from 1.60 to 1.85 Ga. The rocks are peraluminous with A/CNK values of 0.99–1.08. The granites display high Si, Al and K contents but low Mg, Fe and Ca contents. The rocks show flat chondrite-normalized REE patterns with strong Eu negative anomalies. These characteristics indicate that the magma originated from a continental crustal source. The hydrothermal muscovite exhibits an Ar–Ar plateau age of 50.4 ± 0.2 Ma. The δ 18 O and δD values of hydrothermal quartz from the deposit range from −7.32‰ to 4.01‰ and from −124.9‰ to −87.1‰, respectively. The δ 13 C PDB and δ 18 O SMOW values of calcite range from −11.3‰ to −3.7‰ and from +2.2‰ to +12.7‰, respectively. The sulfur isotopic compositions (δ 34 S V–CDT ) range from +3.3‰ to +8.6‰ for sulfide separates, and the lead isotopic ratios 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb range from 18.668 to 18.746, from 15.710 to 15.743 and from 39.202 to 39.295, respectively. These isotopic compositions are similar to those of magma–derived fluids, indicating that the ore–forming fluids and materials mainly originated from magmatic rocks with some input from meteoric water. This evidence suggests that the tin mineralization is closely linked to the Lailishan I–type granites. In combination with previous data, it is proposed in this study that widespread early Eocene magmatism resulted from the slab breakoff of the subducting Neo-Tethyan slab at ca. 55 Ma.

Manganese is mostly used in the iron and steel industry and serves as an important metal mineral in the national economy. It is difficult to substantially increase the output of China&rsquo, s manganese ore because it is of low grade and high impurity content. However, as a large consumer in the world, it is very important to ensure the long-term stable supply of this mineral. Collecting historical data on manganese ore in China over the past 20 years, we identified and evaluated risks during the whole process of production, supply, consumption, reserves, and trade of resources using the Volkswagen and German Federal Institute for Geosciences and Natural Resources (VW-BGR) method by selecting nine indicators: current market equilibrium, market price volatility, Reserve/production ratio, import dependence, import concentration, country risks, country concentration and future supply and demand trend. Furthermore, we assessed its economic importance by calculating the contribution of manganese ore involved in different value chains. It shows the same downward trend both in manganese ore consumption and economic importance, and the future demand of manganese ore will slow down, and the global supply will exceed demand. Based on the comprehensive evaluation of supply and demand trends in the past and future, it was concluded that the current market balance, import dependence and country concentration risks are the main driving factors for the supply risk of manganese ore in China, showing higher supply risk than that of the other factors, the resource and geostrategic risks are moderate, and may significantly reduce the supply risk if effective measures are implemented. As per the aforementioned analysis, to address the risk of supply interruption, this study provides some suggestions and measures, such as strengthening resource reserves and low-grade manganese ore utilization at home, actively exploring foreign markets, exploiting overseas resources, expanding import channels, extending the industrial chain, and adopting equity mergers and acquisitions abroad.

Xiaolonghe is a poorly studied greisen-type tin deposit that is hosted by biotite granite in the western Yunnan tin belt. The mineralisation-related metaluminous and weak peraluminous granite is characterised by high Si, Al and K and low Mg, Fe and Ca, with an average A/CNK of 1.02. The granite is enriched in LILEs (K and Rb), LREEs and HFSEs (Zr, Hf, Th, U and Ce) and depleted in Ba, Nb, Sr, P, and Ti, with zircon eHf(t) = − 10.8 to − 7.5 (T DM2 = 1.61–1.82 Ga). These characteristics indicate that the magma was generated by the partial melting of a thickened ancient crust. LA-ICP-MS U–Pb dating of igneous zircon and hydrothermal cassiterite yield ages of 71.4 ± 0.4 Ma and 71.6 ± 4.8 Ma, respectively. The igneous biotite and hydrothermal muscovite samples show Ar–Ar plateau ages of 72.3 ± 0.4 Ma and 70.6 ± 0.2 Ma, respectively. The close temporal relationship between the igneous emplacement and hydrothermal activity suggests that the tin mineralisation was closely linked to the igneous emplacement. The δ 18 O and δD values for the deposit range from + 3.11‰ to − 4.5‰ and from − 127.3‰ to − 94.7‰, respectively. The hydrothermal calcite C and O isotopic data show a wide range of δ 13 C PDB values from − 5.7‰ to − 4.4‰, and the δ 18 O SMOW values range from + 1.4‰ to + 11.2‰. The δ 34 S V-CDT data range from + 4.8‰ to + 8.9‰ for pyrite, and the 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios range from 18.708 to 18.760, from 15.728 to 15.754 and from 39.237 to 39.341, respectively. The stable isotopic (C–H–O–S–Pb) compositions are all similar to those of magmatic and mantle-derived fluids, which indicate that the ore-forming fluids and materials were mainly derived from magmatic sources that were accompanied by meteoric water. The tin mineralisation in the Xiaolonghe district was closely associated with the Late Cretaceous crustal-melting S-type granites that formed during the subduction of the Neo-Tethys oceanic lithosphere. Combined with the tin deposits in the Southeast Asian tin belt, Tengchong block and Central Lhasa, we interpreted that a giant intermittent tin mineralisation belt should be present along the Asian Neo-Tethys margin.

The newly discovered Jiaojiguan deposit, a medium-scale skarn iron-tin polymetallic deposit on the Sino-Burma boundary of Yunnan Province (SW China), is spatially associated with the biotite monzonitic granite. Here, we report new in situ zircon LA-MC-ICP-MS U–Pb ages, trace element and Hf isotope data from the granite, and U–Pb dating ages of cassiterite from the ore bodies. In this study, we obtain a weighted mean 206Pb/238U age of 124.1 ± 1.4 Ma for the zircon and a 207Pb/206Pb-238U/206Pb intercept age of 123.8 ± 2.2 Ma for the cassiterite. The granite crystallized during the Early Cretaceous, with zircons exhibiting eHf(t) values from −5.8 to −0.6 and two-stage Hf model ages (TDM2) of 1.21–1.54 Ga. The close temporal and spatial links between pluton emplacement and ore-forming events suggest that magmatic-hydrothermal events were the key factors that triggered the genesis of the iron-tin polymetallic deposits in the area. Regional geochronological data show that tin mineralization took place t...

The Yujiadian F-Pb-Zn-Ag deposit in the South Great Xing’an Range (SGXR) consists of vein-type fluorite and F-Pb-Zn-Ag mineralization associated with granitoid. The orebodies occur in NS-trending extensional faults. Wallrock alterations are characterized by a series of medium-low temperature hydrothermal alteration, including silification, kaolinization, chloritization, sericitization, pyritic and carbonate alteration. Four stages of primary paragenetic sequences are recognized: polymetallic sulfide stage (stage I), sulfide fluorite sub-stage (stage II-1), silver-fluorite sub-stage (stage II-2), pure fluorite stage (stage III) and late carbonate stage (stage IV). Silver mineralization primarily belongs to the stage II. The 139–135 Ma quartz syenite porphyry is metaluminous and peralkalic, and is classified as A-type granite that formed in a post-orogenic extensional setting. The δ34S (1.8‰) of hydrothermal fluid calculated from coeval minerals (barite and galena) is comparable with the majority of adjacent magmatic hydrothermal deposits in the SGXR, implying a magmatic source. Microthermometric measurements show that ore minerals were deposited at intermediate temperatures (109.7–320.1 °C) and had low salinities (0.18–5.62 wt% NaCl equive). Ore-forming fluid originated from post-magmatic hydrothermal fluid and mixed with heated meteoric water. Successive precipitation of base metals occurred with changing physicochemical conditions and boiling of ore fluid. The main precipitation mechanism for fluorite in the late stage is related to fluid-rock reaction. We propose that the A-type granite related to the fracture-controlled hydrothermal vein-type Yujiadian F-Pb-Zn-Ag deposit forms part of the magmatic response to Paleo-Pacific subduction and associated lithospheric thinning, extension and delamination processes. Furthermore, the deposit represents the terminal and distal member of the regional Mesozoic large-scale mineralization events.

The Cuonadong deposit is located in the Cuonadong gneiss dome of the eastern Tethyan Himalaya and is characterized as a large- to superlarge-scale Sn polymetallic deposit in the Himalaya orogen. The mineralization pattern includes skarn W-Sn mineralization in the strong shear zone of the dome mantle, hydrothermal Sn-W veins controlled by north-south-trending rifts (NSTRs), and Be-Rb mineralization in pegmatitic leucogranite. The results of this study show that the zircon U-Pb age of undeformed (postkinematic) leucogranites is 15.5 ± 0.1 Ma (n = 28, MSWD = 1.4), the cassiterite U-Pb age of the vein-type Sn-W orebody is 14.3 ± 0.5 Ma (n = 40, MSWD = 3.2), and the muscovite Ar-Ar age of beryl-bearing pegmatitic leucogranite is 15.2 ± 0.2 Ma (MSWD = 1.5). The isotopic dating results demonstrate that the Cuonadong Sn-W-Be-Rb mineralization has a close genetic relationship with the Miocene (ca. 16–14 Ma) leucogranite magmatic hydrothermal activity in the Cuonadong dome. The deformed (synkinematic) two-mica granite (18 Ma) was cut by the Sn-W ore veins (14 Ma) faulted by NSTRs, indicating that the E-W-trending extension of the NSTRs initiated at ca. 18–14 Ma. The Himalaya leucogranite belongs to a highly fractionated granite with high Sn content (>15 ppm). In conclusion, the Himalaya leucogranite is considered to be tin granite in this study, and therefore, the Himalaya presents high potential for Sn polymetallic mineralization prospecting.

The authors would like to make the following corrections about the published paper [...]

The widespread use of reclaimed water has alleviated the water resource crisis worldwide, but long-term use of reclaimed water for irrigation, especially in agricultural countries, might threaten the soil environment and further affect groundwater quality. An in-situ experiment had been carried out in the North China Plain, which aimed to reveal the impact of long-term reclaimed water irrigation on soil properties and distribution of potentially toxic elements (As, Cd, Cr, Hg, Zn and Pb) in the soil profile as well as shallow groundwater. Four land plots were irrigated with different quantity of reclaimed water to represent 0, 13, 22 and 35 years&rsquo, irrigation duration. Pollution Load Index (PLI) values of each soil layer were calculated to further assess the pollution status of irrigated soils by potentially toxic elements (PTEs). Results showed that long-term reclaimed water irrigation caused appreciable increase of organic matter content, and might improve the soil quality. High soil organic matter concentrations conduced to high adsorption and retention capacity of the soils toward PTEs, which could reduce the risk of PTEs leaching into deep layers or shallow groundwater. Highest levels of Cr, Pb and Zn were observed at 200&ndash, 240 cm and 460&ndash, 500 cm horizons in plots. Longer irrigation time (35 years and 22 years) resulted in a decreasing trend of As, Cd, Hg, Pb and Zn in lower part of soil profiles (&gt, 540 cm) compared with that with 13-years&rsquo, irrigation years. Long-term reclaimed water irrigation still brought about increases in concentrations of some elements in deep soil layer although their content in soils and shallow groundwater was below the national standard. Totally speaking, proper management for reclaimed water irrigation, such as reduction of irrigation volume and rate of reclaimed water, was still needed when a very long irrigation period was performed.