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The Tiegelongnan porphyry-epithermal deposit (2089 Mt @ 0.53% Cu, 0.08 g/t Au) is host to a large variety of Cu-sulfide minerals, mainly chalcopyrite, bornite, covellite, digenite, enargite, and tennantite. We used LA-ICP-MS to investigate the trace element geochemistry of the Tiegelongnan Cu-sulfides, as well as pyrite, to understand the correlation between sulfides and trace elements, gold in particular, in the porphyry and epithermal systems. Porphyry mineralization consists of stage 1 chalcopyrite-pyrite ± molybdenite, stage 2 chalcopyrite-bornite, and stage 3 covellite. Epithermal sulfides form stage 4 pyrite-alunite, stage 5 digenite-bornite-chalcopyrite, and stage 6 enargite-tennantite ± tetrahedrite. Stage 2 chalcopyrite (S2 Ccp, median = 9.7 ppm Au) is the primary porphyry Au host, and stage 6 tennantite in alunite veins (S6 Tnt-s, median = 98.0 ppm Au) is the major epithermal Au host. These Au-rich sulfides formed under higher oxidation conditions, suggesting that a high oxidation state favors the incorporation of Au in Cu-sulfides. Gold contents in coeval chalcopyrite and bornite are positively correlated to temperature, and Au is enriched in chalcopyrite over bornite at low temperatures (< 350 ℃). Positive correlations between Au and As and Te in covellite and chalcopyrite result from the reaction of As3+ + (Au+/Ag+) + Te2− ↔ 4Cu+ + S2−. Epithermal chalcopyrite and bornite contain more As and Pd than that in porphyry stages, and high contents of As, Sn, Cd, Zn, Sb, Te, Au, and Bi in epithermal enargite and tennantite are likely the result of partitioning of these elements in sulfides at low epithermal temperatures. Epithermal overprinting likely leached Cu from earlier porphyry stage sulfides to precipitate high Cu-grade epithermal mineralization. The Cu-sulfides and related trace elements show a spatial distribution, potentially useful for the exploration of overprinted porphyry-epithermal systems. [ABSTRACT FROM AUTHOR]

More than 200 years since its initial exploration, Zanda Basin, a high-elevation (3,800–4,500 m above sea), intermountain basin at the foothills of the Himalaya, is the site to some of the earliest fossil discoveries, including the holotype of extinct Tibetan antelope, Qurliqnoria hundesiensis. These fossils also hold the record, in 1823, as the first vertebrate fossils from Tibet in the scientific literature. Unfortunately, these tantalising early records have become all but forgotten for more than 100 years due to a lack of information about their localities. Our recent explorations in the 2000s revive the interests in Zanda Basin and establish a unique Zanda mammal assemblage important in the evolution of Tibetan Neogene mammals. In this paper, we retrace the expedition routes by early explorers and attempt to establish, to the extent possible, the type locality of two key mammals in the Zanda fauna: Q. hundesiensis and Hipparion (Plesiohipparion) zandaense. We highlight the pivotal role Zanda fossil mammals play in the early discourse of mountain building, climate change, and mammal adaptation in high Himalaya, more than a hundred years before Chinese palaeontologists made a similar argument upon the discovery of three-toed horses, in the 1980s, at different basins in Tibet. [ABSTRACT FROM AUTHOR]

The microecological effects of plateau uranium mining are still unknown. In this study, we used 16S rRNA high-throughput sequencing to analyze the impact of plateau uranium mining on the microbial diversity and community structure of tailings soil, tunnel soil, and soil at different depths in an open pit. The results showed that uranium mining significantly reduced soil microbial community richness and diversity indicators, including Chao1, Pielou evenness, and Shannon index (P < 0.05). Uranium mining activities significantly reduced the abundance of RB41, Vicinamidactaceae , and Nitrospira (P < 0.05). Interestingly, the abundance of Thiobacillus , Sphingomonas , and Sulfuriferula significantly increased in the soil samples from various environments and depths during uranium mining (P < 0.05). Beta diversity analysis found that uranium mining resulted in the differentiation of soil microbial communities. Functional enrichment analysis found that uranium mining resulted in the functional enrichment of DNA binding response regulator, DNA helicase, methyl-accepting chemotaxis protein, and Helicase conserved C-terminal domain, whereas cell wall synthesis, nonspecific serine/threonine protein kinase, RNA polymerase sigma-70 factor, and ATP binding cassette transporter were significantly affected by uranium mining (P < 0.05). In addition, we also found that different uranium mining environments and soil depths enriched diverse microbial populations and functions to cope with the environmental pressures that were elicited by uranium mining, including Gaiella , Gemmatimonas , Lysobacter , Pseudomonas , signal transformation histidine kinase, DNA-directed DNA polymerase, and iron complex outer membrane receptor protein functions (P < 0.05). The results have enhanced our understanding of the impact of uranium mining on plateau soil microecological stability and the mechanism of microbial response to uranium mining activities for the first time and aided us in screening microbial strains that can promote the environmental remediation of uranium mining in plateaus. [Display omitted] • Uranium mining reduced soil microbial community richness and diversity. • Thiobacillus, Sphingomonas, and Sulfuriferula increased in uranium mining area. • Uranium mining resulted in the functional enrichment of DNA binding response regulator, etc. • Diverse bacteria and functions were enriched in various mining environments and soil depths. • The study improves our understanding of the microecological influence of uranium mining on plateau soil. [ABSTRACT FROM AUTHOR]

Anaemia during pregnancy, characterised by Hb <110 g/l, is a specific risk factor for adverse maternal and perinatal outcomes in developing countries. The objective of this study was to determine the effectiveness of daily antenatal supplementation with multiple micronutrients (MMN) compared with folic acid (FA) on the occurrence of anaemia among pregnant women and their infants’ health in a high-altitude area. A prospective cohort study was carried out in two rural counties in Tibet from 2007 to 2012. A total of 1149 eligible pregnant women were allocated daily supplementation with FA in one county and MMN containing a recommended allowance of twenty-three vitamins and minerals in another county starting ≤24 weeks of gestation and continuing until delivery. Compared with the FA group, prenatal supplementation with MMN was significantly associated with reduced odds of anaemia in the third trimester. This was demonstrated in the primary outcome, with an adjusted OR (AOR) of 0·63; 95 % CI 0·45, 0·88 and P=0·007 and also reduced odds of preterm delivery (AOR: 0·31; 95 % CI 0·15, 0·61; P=0·001). There was no difference between MMN and FA groups in mean birth weight (adjusted mean difference: 36·78; 95 % CI −19·42, 92·98 g; P=0·200), whereas MMN supplementation significantly reduced the odds of low-birth weight (LBW) babies (AOR: 0·58; 95 % CI 0·36, 0·91; P=0·019). In conclusion, the antenatal MMN supplementation in rural Tibet is associated with a reduction of maternal anaemia in the third trimester, and may potentially decrease the risk of preterm delivery and LBW babies. [ABSTRACT FROM AUTHOR]

The “out of Tibet” hypothesis envisions late Cenozoic Tibetan mammals acquiring adaptations to cold environments and being ancestral to several Eurasian megafaunal species in the Pleistocene. Here we report an early record of a hypercarnivorous canid, Sinicuon cf. Sinicuon dubius , from Zanda Basin in the Himalaya Range. Although the new record is recovered from reworked sediments in a Pleistocene alluvium, we can constrain the fossil to within a narrow age range of 3.8–3.4 Ma in the middle Pliocene. Presence of this hypercarnivorous canid in the Pliocene of Tibet, along with the recently described pantherine cat and arctic fox, suggests a predator guild with predominately carnivorous diet characteristic of modern arctic carnivorans such as the arctic fox and polar bear. Wintering in extremely cold climates may have been the cause of such adaptations. Sinicuon shows transitional morphology to modern hypercarnivorous hunting dogs in southern Asia ( Cuon ), suggesting linkage of the high Tibetan Plateau to the southern continents. [ABSTRACT FROM AUTHOR]

The distal extremity of a rhinocerotid humerus from the upper part of the Dingqing Formation at the Lunbori locality in Baingoin County, northern Tibet, is the first mammalian fossil found in Cenozoic deposits of the Lunpola Basin. The medial condyle of the distal trochlea of the humerus specimen from Lunbori gradually contracts from medially to laterally. The margin of the medial surface of the medial condyle is not prominent, the well-developed medial epicondyle strongly extends posteriorly, and is divided from the articular facet of the medial condyle by a groove; all of which are characteristic for the Rhinocerotidae. The medial condyle is wide at the bottom and narrow at the top. The medial collateral ligament fossa is relatively shallow, and the medial collateral ligament tubercle is very weak. The medial part of the upper margin of the medial condyle smoothly connects to the bony surface above, but there is no clear boundary between them. All of these characteristics are identical with those of Plesiaceratherium. These comparisons imply that the Lunbori specimen is closest to Plesiaceratherium gracile in the Shanwang Fauna from Linqu, Shandong Province, in size and morphology. Thus, its age is suggested to be the late Early Miocene (Shanwangian Age), about 18-16 Ma. Discovery of the rhinocerotid fossil suggests that the upper part of the Dingqing Formation deposited in the Neogene. While adjusting to paleo-temperatures of the Early Miocene, a paleo-ecosystem reconstruction indicates that the paleo-elevation was close to 3000 m in the Lunpola Basin during this time. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cretaceous granites formed from subduction-related metasomatized sources. • Tin-fertile granites are highly fractionated, reduced, and derived from dry magma. • Copper-Mo-fertile granites are water-rich, oxidized, and weakly fractionated. • Different magma sources are primary controls on the contrasting metal association. The metal and sulfur fertility of granite magmas that formed in post-subduction settings, the key processes that led to their contrasting associated polymetallic mineral deposits, and their post-subduction source remain obscure. The Yidun Terrane, eastern Tibet, extends for 500 km and can be divided into the northern Yidun Terrane (NYT) and southern Yidun Terrane (SYT) based on distinctive magmatic source affinities and related mineral deposits. The NYT has several 103–93 Ma granite plutons and associated magmatic-hydrothermal vein-type Sn–Pb–Zn–Ag polymetallic deposits, such as the giant Xiasai deposit. In contrast, the SYT granites host the Xiuwacu porphyry Mo–W deposit (88–84 Ma) and several porphyry or porphyry–skarn-type Cu–Mo deposits (85–78 Ma), such as Relin, Hongshan and Tongchanggou. The contrasting nature of the causative Cretaceous post-subduction granites and their source is determined from their whole-rock and isotope geochemistry, zircon trace-element concentrations, and biotite and amphibole mineral chemistry. Based on these parameters, the NYT Sn–Pb–Zn–Ag deposits are associated with highly fractionated, reduced ilmenite-series granites derived from a relatively dry magma that formed via mixing between amphibolite-derived and greywacke- and orthogneiss-derived metasomatized crustal melts. In contrast, the SYT Mo–W deposits are associated with strongly- to moderately-evolved and fractionated, oxidized intermediate-series granites. The SYT Cu–Mo deposits are related to more hydrous and less fractionated magnetite-series granites. The granites associated with both Mo–W and Cu–Mo deposits in the SYT were generated by partial melting of metasomatized ancient mafic-intermediate lower continental-crust with variable contributions of metasomatized mantle components. However, there is only evidence for the presence of garnet as a residual phase in the magmatic source of the SYT Cu–Mo-bearing granites. The different magma sources were important in determining the redox state of the Yidun granite magmas, providing a fundamental control on the behaviour of metals and sulfur in fractionating melts and dictating the contrasting polymetallic compositions of causative magmatic-hydrothermal fluids and resultant mineral deposits. The source regions of the granites are thus the primary control on the spatial distribution of the Sn–Pb–Zn–Ag, Mo–W, and Cu–Mo belts in the Yidun Terrane. Although not derived during subduction, as for most Cenozoic porphyry systems, the Yidun deposits are indirectly related to subduction via the metasomatism and fertilization of the mantle lithosphere and lower crust during the earlier subduction phase. The anomalous preservation of Cretaceous porphyry systems in the Yidun Terrane relates to their proximity to the margin of the Yangtze Craton, whose thick buoyant lithosphere inhibited exhumation and erosion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Gangdese Miocene fertile and barren adakite-like intrusions share similar ΔFMQ values and apatite S concentrations. • Variations of apatite Cl and S concentrations from core to rim indicate fluid exsolution in fertile and barren rocks. • Some barren porphyries have higher apatite/melt Cl concentrations than the fertile intrusions. • Enrichment of melt Cl and S alone is not critical to forming economic porphyry copper mineralization. • Caution must be taken when applying compositions of detrital zircon and apatite grains to ore prospecting. Gangdese porphyry copper belt in southern Tibet of China contains many Miocene fertile and barren adakite-like intrusions. Their magmatic oxidation state and volatile concentrations were poorly constrained. Here, we present apatite and zircon composition data for the Miocene fertile intrusions in the Qulong, Jiru, and Zhunuo porphyry copper deposits, and the coeval barren porphyries at Yare, Mayum, and Lasa in the Gangdese belt. Magmatic zircons of intrusions from the six locations share similar ΔFMQ (FMQ represents the reference buffer fayalite + magnetite + quartz) values, indicating both fertile and barren rocks have similar magmatic oxidation state. Variations of apatite Cl concentrations and characteristics of S- and Cl-rich core to abruptly S- and Cl-poor rim at Qulong, Jiru, Zhunuo, Yare, and Mayum are indicative of fluid exsolution from vapor-saturated magma. In contrast, fluid exsolution was not recognized from the available apatite composition data at Lasa which are characterized by constant or increasing apatite Cl concentrations with decreasing F/Cl ratios from core to rim. Some apatites at Lasa have high SO 3 concentrations at the core compared with the rim, which would be attributed to early crystallization from S-rich magma followed by crystallization of sulfate minerals in a vapor-undersaturated magma. Some apatites from the fertile intrusions at Qulong, Jiru, and Zhunuo have lower Cl concentrations than those from the barren rocks at Yare, Mayum, and Lasa, which is consistent with the observation from the calculated melt Cl concentration. In addition, the SO 3 concentrations at the core of apatites from all the fertile rocks are overlapping with those from all the barren rocks. Therefore, enrichment of Cl and S alone in melts may not be critical to forming economic porphyry copper mineralization in the Gangdese belt. Cautions must be taken when using compositions of detrital zircon and apatite grains to evaluate metallogenic potential during regional geochemical surveys. [ABSTRACT FROM AUTHOR]

Two new species of fossil hamsters (Cricetinae, Cricetidae) collected from early Pliocene sediments (∼4.4 Ma) in the Zanda Basin, southwestern Tibet (China), demonstrate greater past diversity among cricetines in the hinterland of the Tibetan Plateau within the Himalayan Range (beyond the previously known ‘Plesiodipus’ thibetensis from the late Miocene of the Gyirong Basin). The occurrence of Nannocricetus qiui, sp. nov., in the Zanda Basin indicates a dispersal of Nannocricetus from its center of origin in northern and northwestern China and the Mongolian Plateau, into the hinterland of the high-elevation Tibetan Plateau and subsequently into the Himalayan Range. The new taxon Aepyocricetus liuae, gen. et sp. nov., possibly represents a specialized (and endemic) Neogene hamster from the Tibetan Plateau. The dispersal of these hamsters into the high-elevation portions of Tibet during the early Pliocene contrasts with the hypothesized biogeographic shift of several large mammal lineages out of Tibet. The absence of Aepyocricetus and Nannocricetus from adjacent portions of the south slope of the Himalayans (and the Siwalik Hills in India and Pakistan) further implies that the Himalayan range functioned as a dispersal barrier for these small mammals by the early Pliocene.http://zoobank.org/urn:lsid:zoobank.org:pub:9EE286AA-0C00-4041-8F0C-877B35283181.SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVPCitation for this article: Li, Q., T. A. Stidham, X. Ni, and L. Li. 2018. Two new Pliocene hamsters (Cricetidae, Rodentia) from southwestern Tibet (China), and their implications for rodent dispersal ‘into Tibet’. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1403443. [ABSTRACT FROM AUTHOR]

• Early- and late-stage pyrite have high concentrations of Au and As at Bangbu. • Sulfur for mineralization was derived from the Greater Himalayan crystalline complex. • Bangbu deposit occurred during or after amphibolite-facies metamorphism during ~50–45 Ma. The Bangbu orogenic gold deposit in the North Himalaya of the southern Tibet contains more than 40 t Au at an average grade of 7.0 g/t. In this deposits, gold-bearing quartz veins were controlled by nearly E-trending Qusong-Cuogu-Zhemulang shear zone and occurred within the secondary faults which crosscut Late Triassic greenschist- facies rocks. To further understand the sulfur source and ore-forming process, we have conducted a compressive study of in-situ SIMS sulfur isotopes and LA-ICP-MS trace element compositions of two stages of pyrite at Bangbu. Early-stage pyrite (Py1) is coarse-grained (mostly 0.2–2 mm) and euhedral, and has gold concentrations of less than 0.3–54 ppm (mean of 20 ppm) and δ34S values of 1.6–5.1‰ (mean of 3.2‰). Late-stage pyrite (Py2) is generally fine-grained (mostly <50 μm to 1 mm) and subhedral to anhedral, and has gold concentrations of 3.6–115 ppm (mean of 30 ppm) and δ34S values of 0.9–5.2‰ (mean of 2.7‰). Gold occurs mainly as invisible refractory within Py1 and Py2, and to a lesser extent as native gold within quartz, pyrite, arsenopyrite and sphalerite. Sulfur for Bangbu gold mineralization was probably sourced from the Greater Himalayan crystalline complex. Release of ore-forming fluids was likely related to amphibolite-facies metamorphism during ~50–45 Ma. Ore fluids deposited Au-rich pyrite during early and late mineralization stage and precipitation of native gold was probably related to fluid boiling and/or remobilization of invisible gold within pyrite. [ABSTRACT FROM AUTHOR]

Background and Objectives: There is very limited published data on Tibetan dietary patterns and its association with nutrient intakes and socioeconomic factors. The aim of this study was to identify and describe the dietary patterns and the associations with nutrient intakes in rural Tibetan pregnant, lactating mothers.Methods and Study Design: Dietary patterns and nutrient intakes were identified via a food frequency questionnaire (FFQ). We identified dietary patterns using principle component analysis (PCA) of intakes of 17 food groups and specific Tibetan foods. Quartile categories of each dietary pattern were used, and non-dietary lifestyle factors and total energy intake were adjusted for the analysis. We identified two dietary patterns: "Varied pattern" and "Staple pattern".Result: The "Varied pattern" was characterized by a high intake of vegetables, fruits and soy foods which showed significant positive associations with vitamins. Vitamin C (Ptrend<0.01) and vitamin E (Ptrend<0.01) were strongly associated with "Varied pattern" among mothers with children younger or older than 12 months. The "Staple pattern" was characterized by Tibetan staple foods, Tibetan beverages and Tibetan snacks and showed significant negative associations with protein (Ptrend<0.01) among mothers with children younger than 12 months or older than 12 months. Carbohydrate intakes significantly increased with "Staple pattern" among mother with children younger than 12 months only.Conclusions: The results presented here suggested our dietary patterns to great extent characterize the dietary behavior of Tibetan lactating mothers. There is, therefore, potential for dietary patterns to be used as a valid tool in assessing Tibetan diet. [ABSTRACT FROM AUTHOR]

Ice Age megafauna have long been known to be associated with global cooling during the Pleistocene, and their adaptations to cold environments, such as large body size, long hair, and snow-sweeping structures, are best exemplified by the woolly mammoths and woolly rhinos. These traits were assumed to have evolved as a response to the ice sheet expansion. We report a new Pliocene mammal assemblage from a high-altitude basin in the western Himalayas, including a primitive woolly rhino. These new Tibetan fossils suggest that some megaherbivores first evolved in Tibet before the beginning of the Ice Age. The cold winters in high Tibet served as a habituation ground for the megaherbivores, which became preadapted for the Ice Age, successfully expanding to the Eurasian mammoth steppe. [ABSTRACT FROM AUTHOR]