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Geochronology and Geochemistry of Ore-related Granitoids in the Giant Gariatong Rb Deposit,Tibet and Implications for Rb Metallogeny in China 被引量:1
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作者 LIN Bin TANG Juxing +8 位作者 TANG Pan SUN Yan QI Jing MSANTOSH XIE Jinling DENG Shilin LI Faqiao XIE Fuwei ZHOU Aorigele 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期83-103,共21页
Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated granites.This study investigates a newly-discovered giant Rb deposit at ... Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated granites.This study investigates a newly-discovered giant Rb deposit at Gariatong in the Central Lhasa terrane in Tibet.Detailed field studies and logging data revealed that the Rb mineralization mainly occurs in monzogranite and is related to greisenization.LA-ICP-MS U-Pb dating of zircon yielded ages of 19.1±0.2 Ma and 19.0±0.2 Ma for greisenized monzogranite and fresh monzogranite,respectively.The monzogranites are characterized as strongly peraluminous,with high contents of SiO2,Al2O3,K2O and Na2O as well as a high differentiation index.They are enriched in light rare earth and large ion lithophile elements with significant negative Eu anomalies and depleted high fieldstrength elements.Petrological and geochemical features of these ore-related monzogranites suggest that they are highly fractionated S-type granites,derived from remelting of crustal materials in a post-collisional setting.The geochemistry of zircon and apatite points to a low oxygen fugacity of the ore-related monzogranite during the magma’s evolution.The discovery of the Gariatong Rb deposit suggests that the Central Lhasa terrane may be an important region for rare metal mineralization. 展开更多
关键词 LA-ICP-MS U-Pb dating GEOCHEMISTRY Rb metallogeny Gariatong tibet
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Genesis of the Nuri Cu-W-Mo Deposit,Tibet,China:Constraints from in situ Trace Elements and Sr Isotopic Analysis of Scheelite 被引量:1
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作者 WANG Yiyun WU Zhishan +8 位作者 CHEN Wenqing DU Qing’an TANG Liwei SHI Hongzhao MA Guotao ZHANG Zhi LIANG Wei WU Bo MIAO Hengyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期117-131,共15页
The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controver... The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and a slow rise in pH value.Additionally,the high Mo and low Sr contents in the scheelite are consistent with typical characteristics of magmatic-hydrothermal scheelite.Therefore,considering the geological features of the deposit,the geochemical characteristics of scheelite and the O-H isotope data published previously,it can be concluded that the genesis of the Nuri deposit belongs to porphyry-skarn deposit. 展开更多
关键词 trace elements in situ Sr isotopes tungsten mineralization Gangdese metallogenic belt tibet
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Muscovite^(40)Ar/^(39)Ar isotopic dating of pegmatite veins in the Bieyesamas rare metal deposit in the Altay Mountain,Xinjiang,northwestern China
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作者 Geng-biao Qiao Ping Wang +1 位作者 Xiao-hong Wang Jun-lu Chen 《China Geology》 CAS CSCD 2024年第3期589-591,共3页
1.Objective The Altay Orogenic Belt in Xinjiang,China is located in the west of the Central Asian Orogenic Belt and in the transition zone between the Siberian Plate and the Kazakhstan-Junggar Plate,extending approxim... 1.Objective The Altay Orogenic Belt in Xinjiang,China is located in the west of the Central Asian Orogenic Belt and in the transition zone between the Siberian Plate and the Kazakhstan-Junggar Plate,extending approximately 500 km in northern Xinjiang,China(Fig.1a).The Altay Orogenic Belt has undergone two-way accretion of the Paleozoic crust and the Meso-Cenozoic intracontinental orogeny,leading to the formation of large numbers of intermediate-acid intrusions.More than 100000 pegmatite veins have been discovered in the intermediate-acid intrusions,and they constitute an important rare metal metallogenic belt of China(Fig.1b). 展开更多
关键词 xinjiang dating isotopic
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LA-ICP-MS zircon U-Pb dating of tuffites in the Sachakou Pb-Zn mining area, Karakorum, Xinjiang and its establishment of Early Triassic strata
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作者 Xiao-jian Zhao Nuo Li +5 位作者 Kai Weng Ming Wang Qing-lin Sui Deng-hui Chen Zhou-ping Guo Meng-qi Jin 《China Geology》 CAS CSCD 2024年第1期150-152,共3页
1.Objective In the past decade,a group of medium to giant lead-zinc deposits,represented by Huoshaoyun,Sachakou,and Yuanbaoling,have been discovered in the Aksai Chin region of Karakoram,Xinjiang.They are all located ... 1.Objective In the past decade,a group of medium to giant lead-zinc deposits,represented by Huoshaoyun,Sachakou,and Yuanbaoling,have been discovered in the Aksai Chin region of Karakoram,Xinjiang.They are all located in the Mesozoic carbonate and clastic rock formations.The Sachakou leadzinc mining area is adjacent to the northwest of the Huoshaoyun lead-zinc mining area and is in the same stratigraphic layer as Huoshaoyun.Although many scholars have been arguing about the type and age of Huoshaoyun lead-zinc mineralization,few scholars have paid attention to the classification of the ore-bearing strata in the area.The stratigraphy of the Lower Permian Shenxianwan Group to the Upper Cretaceous Tielongtan Group is exposed in the Sachakou area of Karakorum,Xinjiang,however,the Late Permian-Early Triassic stratigraphy is missing(Fig.1a).Due to the harsh natural conditions in the area and the low level of work,the stratigraphic delineation is not exhaustive,and the regional lithology is dominated by carbonates and clastic rocks,which makes it difficult to identify the age of the regional lithology and causes problems for the exploration and research of lead-zinc in the area. 展开更多
关键词 STRATA TRIASSIC xinjiang
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Mineral Geochemistry of Apatite in the Jiama PorphyrySkarn Deposit,Tibet and its Geological Significance
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作者 YANG Yang TANG Juxing +8 位作者 ZHANG Zebin TANG Pan XIE Fuwei RAN Fengqin YANG Zongyao YANG Huaichao BAI Yun SUN Miao QI Jing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期399-415,共17页
The Jiama deposit,a significant porphyry-skarn-type copper polymetallic deposit located within the Gangdese metallogenic belt in Tibet,China,exemplifies a typical porphyry metallogenic system.However,the mineral chemi... The Jiama deposit,a significant porphyry-skarn-type copper polymetallic deposit located within the Gangdese metallogenic belt in Tibet,China,exemplifies a typical porphyry metallogenic system.However,the mineral chemistry of its accessory minerals remains under-examined,posing challenges for resource assessment and ore prospecting.Utilizing electron microprobe analysis and LA-ICP-MS analysis,this study investigated the geochemical characteristics of apatite in ore-bearing granite and monzogranite porphyries,as well as granodiorite,quartz diorite,and dark diorite porphyries in the deposit.It also delved into the diagenetic and metallogenic information from these geochemical signatures.Key findings include:(1)The SiO_(2) content,rare earth element(REE)contents,and REE partition coefficients of apatite indicate that the dark diorite porphyry possibly does not share a cogenetic magma source with the other four types of porphyries;(2)the volatile F and Cl contents in apatite,along with their ratio,indicate the Jiama deposit,formed in a collisional setting,demonstrates lower Cl/F ratios in apatite than the same type of deposits formed in a subduction environment;(3)compared to non-ore-bearing rock bodies in other deposits formed in a collisional setting,apatite in the Jiama deposit exhibits lower Ce and Ga contents.This might indicate that rock bodies in the Jiama deposit have higher oxygen fugacity.Nevertheless,the marginal variation in oxygen fugacity between ore-bearing and non-ore-bearing rock bodies within the deposit suggests oxygen fugacity may not serve as the decisive factor in the ore-hosting potential of rock bodies in the Jiama deposit. 展开更多
关键词 APATITE METALLOGENESIS mineral geochemistry PORPHYRY JIAMA tibet
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Below-Moho Earthquakes of Tibet,Himalaya,the Indian Foreland,and Worldwide:How,Where and Why?
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作者 Simon LKLEMPERE WANG Shiqi +3 位作者 SONG Xiaohan Jackie RHARRIS Hitank KASAUNDHAN LIANG Xiaofeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期27-29,共3页
We seek to understand lithospheric rheology by mapping continental earthquake depths relative to Moho depth,across the entire India/Asia convergent orogen,and eventually worldwide.Such mapping has particular value in ... We seek to understand lithospheric rheology by mapping continental earthquake depths relative to Moho depth,across the entire India/Asia convergent orogen,and eventually worldwide.Such mapping has particular value in geothermometry,and potentially in identifying regions of delamination.How:We are extending our Sn/Lg method beyond amplitude ratios of regional seismic phases measured on arrays(array Sn/Lg method,Wang and Klemperer,2021)to include frequency proxies for earthquake depth relative to Moho(Wang&Klemperer,2024a,b;Harris et al.,2024). 展开更多
关键词 Continental mantle earthquakes tibet HIMALAYA Indian Foreland
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Present-day Upper-crustal Strain Rate Field in Southeastern Tibet and its Geodynamic Implications:Constraints from GPS Measurements with ABIC Method
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作者 YANG Shaohua PAN Jiawei +1 位作者 LI Haibing SHI Yaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期265-275,共11页
The Earth’s surface kinematics and deformation are fundamental to understanding crustal evolution.An effective research approach is to estimate regional motion field and deformation fields based on modern geodetic ne... The Earth’s surface kinematics and deformation are fundamental to understanding crustal evolution.An effective research approach is to estimate regional motion field and deformation fields based on modern geodetic networks.If the discrete observed velocity field is obtained,the velocity related fields,such as dilatation rate and maximum shear strain rate,can be estimated by applying varied mathematical approaches.This study applied Akaike's Bayesian Information Criterion(ABIC)method to calculate strain rate fields constrained by GPS observations in the southeast Tibetan Plateau.Comparison with results derived from other three methods revealed that our ABIC-derived strain rate fields were more precise.The maximum shear strain rate highlighted the Xianshuihe–Xiaojiang fault system as the main boundary for the outward migration of material in southeastern Tibet,indicating rotation of eastern Tibet material around the eastern Himalaya rather than whole extrusion along a fixed channel.Additionally,distinct dilatation rate patterns in the northeast and southwest regions of the fault system were observed.The northeast region,represented by the Longmenshan area,exhibited negative dilatational anomalies;while the southwest region,represented by the Jinsha River area north of 29°N,displayed positive dilatational anomalies.This indicates compression in the former and extension in the latter.Combined with deep geophysical observations,we believe that the upper and lower crusts of the Jinsha River area north of 29°N are in an entire expanding state,probably caused by the escape-drag effect of material.The presence of a large,low-viscosity region south of 29°N may not enable the entire escape of the crust,but instead result in a differential escape of the lower crust faster than the upper crust. 展开更多
关键词 strain rate differential escape ABIC GPS southeastern tibet
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Geochronology and Petrogenesis of Late Carboniferous to Early Permian Basalts in the Central Lhasa Subterrane, Southern Tibet: Implications for the Evolution of the Sumdo Paleo-Tethys Ocean
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作者 MA Wang LIU Yingchao +4 位作者 YANG Zhusen Jan-Marten HUIZENGA LI Zhenqing YUE Longlong ZHAO Sibo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期955-968,共14页
Basalts from the Late Carboniferous to Early Permian are extensively developed in the central Lhasa subterrane, southern Tibet. Studying the petrogenesis of these rocks may have implications for the late Paleozoic arc... Basalts from the Late Carboniferous to Early Permian are extensively developed in the central Lhasa subterrane, southern Tibet. Studying the petrogenesis of these rocks may have implications for the late Paleozoic arc magmatism along the central Lhasa subterrane uncovering more of the evolution of the Sumdo Paleo-Tethys Ocean and its dynamic mechanism. Basalt samples from the Luobadui Formation in the Leqingla area, NW of Linzhou City in the central Lhasa subterrane, southern Tibet exhibit arc-like geochemical signatures in a subduction-zone tectonic setting characterized by high Al_(2)O_(3) and low TiO_(2) contents, fractionated REE patterns with low Nb/La ratios and high LREE concentrations, and negative HFSE anomalies. Based on their higher Th/Ce, Nb/Zr, and lower Ba/Th, Pb/Nd ratios, slightly negative to positive ε_(Nd)(t) values, and the relatively high Sr-Pb isotopic compositions, these samples were probably derived from partial melting of a depleted mantle source of garnet + spinel lherzolite, metasomatized by subducted sediments around 297 Ma. Modeling of the trace elements indicates that these basalts experienced fractional crystallization of olivine, clinopyroxene and minor plagioclase during magma ascent and eruption. It is proposed that these Late Carboniferous–Early Permian basalts are associated with the northward subduction of the Sumdo Paleo-Tethys Ocean seafloor along the southern margin of the central Lhasa subterrane. 展开更多
关键词 geochemistry northward subduction Sumdo Paleo-Tethys Ocean Lhasa terrane tibet
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A new small baurioid therocephalian from the Lower Triassic Jiucaiyuan Formation, Xinjiang, China
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作者 LIU Jun Fernando ABDALA 《古脊椎动物学报(中英文)》 CSCD 北大核心 2024年第3期201-224,共24页
Several therocephalian species,mainly represented by cranial material from the late Permian,have been reported from China in recent years.Here we describe a tiny new baurioid therocephalian,Jiucaiyuangnathus confusus ... Several therocephalian species,mainly represented by cranial material from the late Permian,have been reported from China in recent years.Here we describe a tiny new baurioid therocephalian,Jiucaiyuangnathus confusus gen.et sp.nov.,from the Jiucaiyuan Formation,Xinjiang,China.The new taxon is represented by a partial snout with occluded partial lower jaw and two postcranial skeletons.Although juvenile in stage,the new species is diagnosed by the following features:round pit in middle of lateral surface of maxilla;lacrimal contact nasal;fossa for dentary tooth on the posterior end of the premaxilla,lateral to the anterior choana;two small vertical triangular ridges extending dorsally and ventrally on the vomerine anterior portion,and bordering a thin vomerine foramen laterally;anterior projection of the lateral part of the frontal on the nasal;symphyseal region of the dentary projected anteriorly;5 upper premaxillary teeth,upper and lower canines absent,diastema between the last premaxillary upper incisor and first maxillary tooth present,no diastema separating anterior from posterior dentition in the mandible,10 maxillary teeth and 12 dentary teeth,posterior postcanine expands mesiodistally,having a main large cusps and tiny anterior and posterior accessory cusps in line;neural arches of the atlas fused by the neural spine,neural spine of the axis projected posteriorly,procoracoid foramen lies between procoracoid and scapula.Features of the dentition resembles those of the small baurioid Ericiolacerta parva from South Africa and Silphedosuchus orenburgensis from Russia.The specimens provide the rare opportunity to know in detail the postcranial skeleton of baurioids. 展开更多
关键词 Jimsar xinjiang Early Triassic Jiucaiyuan Formation Therocephalia Baurioidea
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Mantle Driven Early Eocene Magmatic Flare-up of the Gangdese Arc, Tibet: A Case Study on the Nymo Intrusive Complex
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作者 MA Xuxuan Joseph GMEERT +4 位作者 CAO Wenrong TIAN Zuolin LIU Dongliang XIONG Fahui LI Haibing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期878-903,共26页
Magmatic periodicity is recognized in continental arcs worldwide, but the mechanism responsible for punctuated arc magmatism is controversial. Continental arcs in the Trans-Himalayan orogenic system display episodic m... Magmatic periodicity is recognized in continental arcs worldwide, but the mechanism responsible for punctuated arc magmatism is controversial. Continental arcs in the Trans-Himalayan orogenic system display episodic magmatism and the most voluminous flare-up in this system was in early Eocene during the transition from subduction to collision. The close association of the flare-up with collision is intriguing. Our study employs zircon Lu-Hf and bulk rock Sr-Nd isotopes, along with mineral geochemistry, to track the melt sources of the Nymo intrusive complex and the role of mantle magma during the early Eocene flare-up of the Gangdese arc, Tibet. The Nymo intrusive complex is composed of gabbronorite, diorite, quartz diorite, and granodiorite which define an arc-related calc-alkaline suite. Zircon U-Pb ages reveal that the complex was emplaced between ~50–47 Ma. Zircon Hf isotopes yield εHf(t) values of 8.2–13.1, while whole-rock Sr and Nd isotopes yield εNd(t) values of 2.7–6.5 indicative of magmatism dominated by melting of a juvenile mantle source with only minor crustal assimilation(~15%–25%) as indicated by assimilation and fractional crystallization modeling. Together with published data, the early Eocene magmatic flare-up was likely triggered by slab breakoff of subducted oceanic lithosphere at depths shallower than the overriding plate. The early Eocene magmatic flare-up may have contributed to crustal thickening of the Gangdese arc. This study provides important insights into the magmatic flare-up and its significant role in the generation of large batholiths during the transition from subduction to collision. 展开更多
关键词 MANTLE magmatic flare-up subduction–collision transition Nymo intrusive complex GANGDESE tibet
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Thoughts on Pairing Assistance to Tibet for Promoting Agricultural High-quality Development in Southern Tibet from the Perspective of Agricultural Power
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作者 Zhiguo SUN Li GAO +3 位作者 Yuanpeng SUN Guangchao CAO Xinying ZHOU Xiaoqiang LI 《Asian Agricultural Research》 2024年第3期18-24,共7页
In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style mod... In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries. 展开更多
关键词 PAIRING ASSISTANCE to tibet Southern tibet Shannan CITY Nyingchi CITY AGRICULTURAL high-quality development AGRICULTURAL power
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Texture and Geochemistry of Multi-stage Hydrothermal Scheelite in the Mamupu Cu-Au-Mo(-W)Deposit,Eastern Tibet:Implications for Tungsten Mineralization in the Yulong Belt
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作者 ZHANG Xiaoxu TANG Juxing +7 位作者 LIN Bin WANG Qin HE Liang YAN Gang SHAO Rui WU Qiang DU Qiu ZHAXI Pingcuo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期701-716,共16页
Multistage tungsten mineralization was recently discovered in the Mamupu copper-polymetallic deposit in the southern Yulong porphyry copper belt(YPCB),Tibet.This study reports the results of cathodoluminescence,trace ... Multistage tungsten mineralization was recently discovered in the Mamupu copper-polymetallic deposit in the southern Yulong porphyry copper belt(YPCB),Tibet.This study reports the results of cathodoluminescence,trace element and Sr isotope analyses of Mamupu scheelite samples,undertaken in order to better constrain the mechanism of W mineralization and the sources of the ore-forming fluids.Three different types of scheelite are identified in the Mamupu deposit:scheelite A(Sch A)mainly occurs in breccias during the prograde stage,scheelite B(Sch B)forms in the chlorite-epidote alteration zone in the retrograde stage,while scheelite C(Sch C)occurs in distal quartz sulfide veins.The extremely high Mo content and negative Eu anomaly in Sch A represent high oxygen fugacity in the prograde stage.Compared with ore-related porphyries,Sch A has a similar REE pattern,but with higher ΣREE,more depleted HREE and slightly lower(^(87)Sr/^(86)Sr)i ratios.These features suggest that Sch A is genetically related to ore-related porphyries,but extensive interaction with carbonate surrounding rocks affects the final REE and Sr isotopic composition.Sch B shows dark(Sch B-I)and light(Sch B-II)domains under CL imaging.From Sch B-I to Sch B-II,LREEs are gradually depleted,with MREEs being gradually enriched.Sch C has the highest LREE/HREE ratio,which indicates that it inherited the geochemical characteristics of fluids after the precipitation of HREE-rich minerals,such as diopside and garnet,in the early prograde stage.The Mo content in Sch B and Sch C gradually decreased,indicating that the oxygen fugacity of the fluids changed from oxidative in the early stages to reductive in the later,the turbulent Eu anomaly in Sch B and Sch C indicating that the Eu anomaly in the Mamupu scheelite is not solely controlled by oxygen fugacity.The extensive interaction of magmatic-hydrothermal fluids and carbonate provides the necessary Ca^(2+)for the precipitation of scheelite in the Mamupu deposit. 展开更多
关键词 SCHEELITE GEOCHEMISTRY Mamupu Cu deposit Yulong porphyry copper belt eastern tibet
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Estimation of Potential Habitat of Caragana acanthophylla in Xinjiang Based on Maximum Entropy Model
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作者 Jinglu ZHANG Yali ZHU +2 位作者 Huifang ZHANG Jian GAO Dilixiati·Baoerhan 《Asian Agricultural Research》 2024年第4期14-18,22,共6页
[Objectives]To determine the potential habitat range of Caragana acanthophylla in Xinjiang.[Methods]The known distribution points of C.acanthophylla were used as samples,and a MaxEnt model was developed based on their... [Objectives]To determine the potential habitat range of Caragana acanthophylla in Xinjiang.[Methods]The known distribution points of C.acanthophylla were used as samples,and a MaxEnt model was developed based on their climatic variables to identify key environmental factors affecting the potential habitats of C.acanthophylla through jackknife method and construction of a response relationship between representative variables and habitat suitability;the suitability of habitats for C.acanthophylla in Xinjiang was evaluated based on the output results of the model.[Results](i)The accuracy of the model verified by AUC curve was 0.971,indicating that the potential habitats of C.acanthophylla in Xinjiang predicted by MaxEnt model were highly credible.(ii)The optimum climatic characteristics for the distribution of C.acanthophylla in Xinjiang were:isothermality 18.8%-34%,minimum temperature of coldest month-30℃to-13℃,mean temperature of coldest quarter-18℃ to-4℃,annual precipitation 80-410 mm,precipitation of driest month 0-25 mm,precipitation of driest quarter 0-82 mm,and precipitation of coldest quarter 0-75 mm.(iii)The total potential distribution area of C.acanthophylla in Xinjiang was modeled to be 1.03×10^(5) km^(2),of which 8.54×10^(3)km^(2) was high suitability area,mainly in the front mountain belt of the north slope of Tianshan Mountain in Urumqi City,Changji Hui Autonomous Prefecture,Bortala Mongol Autonomous Prefecture,and Yili Kazak Autonomous Prefecture and the front mountain belt of Barluk Mountain in Tacheng Prefecture.[Conclusions]This study is of great significance for the future scientific management,regeneration,vegetation restoration and ecological protection of C.acanthophylla. 展开更多
关键词 xinjiang CARAGANA acanthophylla MAXENT model POTENTIAL HABITAT
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Spatial and Temporal Distribution Characteristics of Solar Energy Resources in Tibet
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作者 Yanbo Shen Yang Gao +3 位作者 Yueming Hu Xin Yao Wenzheng Yu Yubing Zhang 《Energy Engineering》 EI 2024年第1期43-57,共15页
The Tibet Plateau is one of the regions with the richest solar energy resources in the world.In the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the regi... The Tibet Plateau is one of the regions with the richest solar energy resources in the world.In the process of achieving carbon neutrality in China,the development and utilization of solar energy resources in the region will play an important role.In this study,the gridded solar resource data with 1km resolution in Tibet were obtained by spatial correction and downscaling of SMARTS model.On this basis,the spatial and temporal distribution characteristics of solar energy resources in the region in the past 30 years(1991–2020)are finely evaluated,and the annual global horizontal radiation resource is calculated.The results show that:1)The average annual global horizontal radiation amount in Tibet is 1816 kWh/m^(2).More than 60%of the area belongs to the“Most abundant”(GHI≥1750 kWh/m^(2))area of China’s solar energy resources category A,and nearly 40%belongs to the“Quite abundant”(1400≤GHI<1750)area of China’s solar energy resource category B.2)In space,the solar energy resources in Tibet increased gradually from north to south and from east to west.Lhasa,Central and Eastern Shigatse,Shannan,and Southwestern Ali are the most abundant cities,with a maximum annual radiation level of 2189 kWh/m2.3)In terms of time,the total horizontal radiation in Tibet was the highest in May and the lowest in December.74%of the total area belongs to the“Very stable”(R_(w)≥0.47)area of solar resource stability category A,and 26%belongs to the“stable”(0.36≤R_(w)<0.47)area of solar resource stability category B.Solar energy resources in the region show the characteristics of both strong and stable.Average solar energy resources in the region have shown a fluctuating downward trend over the past 30 years,with an average decline of about 12.86(kWh/m2)per decade.4)In terms of solar radiation resources reaching the earth’s surface,the theoretical total amount of annual horizontal radiation in Tibet is about 240.07 billion tons of standard coal or 222.91 billion kilowatts on average. 展开更多
关键词 tibet solar resource spatiotemporal distribution
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Quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms
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作者 QIN Yanhui MA Haoyuan +3 位作者 ZHANG Lele YIN Jinshuai ZHENG Xionghui LI Shuo 《Journal of Mountain Science》 SCIE CSCD 2024年第1期322-334,共13页
The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering ma... The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP. 展开更多
关键词 Freeze–thaw cycles Quantification Machine learning algorithms Qinghai–tibet Plateau CONCRETE
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Three-Dimensional Density Distribution and Seismic Activity along the Guxiang–Tongmai Segment of the Jiali Fault,Tibet
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作者 FAN Pengxiao YU Changqing +3 位作者 WANG Ruixue ZENG Xiangzhi QU Chen ZHANG Yue 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期454-467,共14页
The Guxiang-Tongmai segment of the Jiali fault is situated northeast of the Namche Barwa Syntaxis in northeastern Tibet.It is one of the most active strike-slip faults near the syntaxis and plays a pivotal role in the... The Guxiang-Tongmai segment of the Jiali fault is situated northeast of the Namche Barwa Syntaxis in northeastern Tibet.It is one of the most active strike-slip faults near the syntaxis and plays a pivotal role in the examination of seismic activity within the eastern Himalayan Syntaxis.New study in the research region has yielded a 1:200000 gravity dataset covering an area 1500 km^(2).Using wavelet transform multiscale decomposition,scratch analysis techniques,and 3D gravity inversion methods,gravity anomalies,fault distributions,and density structures were determined across various scales.Through the integration of our new gravity data with other geophysical and geological information,our findings demonstrate substantial variations in the overall crustal density within the region,with the fault distribution closely linked to these density fluctuations.Disparities in stratigraphic density are important causes of variations in the capacity of geological formations to endure regional tectonic stress.Earthquakes are predominantly concentrated within the density transition zone and are primarily situated in regions of elevated density.The hanging wall stress within the Guxiang-Tongmai segment of the Jiali fault exhibits a notable concentration,marked by pronounced anisotropy,and is positioned within the density differential zone,which is prone to earthquakes. 展开更多
关键词 SEISMICITY deep-density structure wavelet transform multi-scale decomposition scratch analysis 3D gravity inversion Jiali fault tibet
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Lighting Up Lives The rise of renewable energy in Hami, Xinjiang
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作者 Si Thu Tun 《China Report ASEAN》 2024年第10期30-31,共2页
Any time of the year,Hami,a city in northwest China's Xinjiang Uygur Autonomous Region,is memorable for its unique food and stunning landscapes set against the majestic Tianshan Mountains.However,September's s... Any time of the year,Hami,a city in northwest China's Xinjiang Uygur Autonomous Region,is memorable for its unique food and stunning landscapes set against the majestic Tianshan Mountains.However,September's significant temperature drops once the sharp rays of sunset beneath the Gobi Desert make Hami an even more fascinating seasonal destination.The renowned sun-drenched scenery is ideal for renewable energy projects such as wind,solar,and hydrogen power.The region also hosts one of China's two supercomputers,which requires significant energy. 展开更多
关键词 xinjiang BENEATH TIANSHAN
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From Poverty to Prosperity How relocation to Aktas Town is a living-standards leap for Xinjiang people
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作者 Antony Hardi 《China Report ASEAN》 2024年第10期40-41,共2页
"3,000 yuan per month,"proclaimed Abdulaziz Mehmet,a Uygur worker at Dena Shoes Factory in Kargilik County of Xinjiang Uygur Autonomous Region.Why is it noteworthy?Bangkok's minimum wage in 2024 is US$32... "3,000 yuan per month,"proclaimed Abdulaziz Mehmet,a Uygur worker at Dena Shoes Factory in Kargilik County of Xinjiang Uygur Autonomous Region.Why is it noteworthy?Bangkok's minimum wage in 2024 is US$327.65,while Jakarta is US$332.92.Mehmet is earning significantly more than what he would getin either of the national capitals. 展开更多
关键词 xinjiang RELOCATION claimed
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Path to Green Growth——The Xinjiang example
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《China Report ASEAN》 2024年第10期16-17,共2页
A key part of achieving high-quality development is promoting the greening and decarbonization of economic and social development.Opinions on Accelerating the Comprehensive Green Transformation of Economic and Social ... A key part of achieving high-quality development is promoting the greening and decarbonization of economic and social development.Opinions on Accelerating the Comprehensive Green Transformation of Economic and Social Development,jointly issued by the Central Committee of the Communist Party of China and the State Council in August,provided a roadmap for China's green transformation.As a major energy base in western China,Xinjiang Uygur Autonomous Region leads the nation in installed capacity of both fossil energy like coal,oil,and natural gas and renewable energy like wind and solar.In recent years,leveraging its resource endowment and industrial foundation,Xinjiang has been enhancing efforts to transform traditional high energy-consuming industries into energy-saving and low-carbon industries and vigorously develop wind,solar,and hydrogen energy,as well as cloud computing.Its achievements in these areas have provided a blueprint that can be followed by any region pursuing green industrial transformation and high-quality development This September,China Report ASEAN journalists flew to Xinjiang and conducted interview and investigations in the regional capital Urumqi,the oil city of Karamay,and Hami,dubbed Xinjiang's"eastern gateway,"to shed light on how the autonomous region seeks to foster economic growth while ensuring environmental sustainability. 展开更多
关键词 jointly xinjiang INTERVIEW
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Analysis of Dry-Wet Climate Change Characteristics and Main Influencing Factors in Main Grain Producing Area of Tibet from 1980 to 2021
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作者 Sangbu ZHUJIE Cunjie ZHANG +3 位作者 Puchi ZHAXI Deji BAIMA Lamu NIMA Ciwang PINGCUO 《Agricultural Biotechnology》 2024年第2期43-49,63,共8页
Based on the daily meteorological observation data of seven meteorological stations in southern Tibet from 1980 to 2021 (April-October), the temporal and spatial variation characteristics and influencing factors of ar... Based on the daily meteorological observation data of seven meteorological stations in southern Tibet from 1980 to 2021 (April-October), the temporal and spatial variation characteristics and influencing factors of aridity index ( AI ) in the growing season of major grain producing areas in Tibet were studied by using climate tendency rate, Mann-Kendal test, Morlet wavelet analysis, GIS hybrid interpolation method, Pearson correlation coefficient, contribution rate analysis and other methods. The results showed that the average AI in the main grain producing areas of Tibet was 1.7, which belonged to the semi-arid area, and the overall trend was decreasing (humidifying) (-0.036/10 a). The linear decreasing trend was different in different regions, and the area around Lhatse County was the most significant (-0.26/10 a). AI had no obvious abrupt change, and had long- and medium-term fluctuation characteristics of 24 years, 6 years. The spatial distribution was uneven, and had the characteristics of ‘shrinking arid area and expanding humid area . The contribution rates of the main climate influencing factors of AI varied in different regions. In general, the contribution rates after quantification was as follows: precipitation (34.9%)>relative humidity (28.4%)>sunshine (19.9%)>maximum temperature (12.4%). 展开更多
关键词 tibet Main production area CLIMATE ARIDITY Contribution rate
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