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Field survey of building damage at Mandalay during 2025 Myanmar M_(w)7.7 earthquake 被引量:1
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作者 Wang Tao Zhou Yujiang +3 位作者 Chen Jie Wang Xiaoqing Bi Hongyi Wang Xiaoting 《Earthquake Engineering and Engineering Vibration》 2025年第3期613-627,共15页
On March 28,2025,an M_(w) 7.7 earthquake struck near Mandalay,Myanmar,producing intense ground shaking.Strong motion recorded at a station close to the fault indicated a peak ground acceleration of 1.066 g in the vert... On March 28,2025,an M_(w) 7.7 earthquake struck near Mandalay,Myanmar,producing intense ground shaking.Strong motion recorded at a station close to the fault indicated a peak ground acceleration of 1.066 g in the vertical direction and 0.631 g in the horizontal direction.The earthquake caused collapse or severe damage of numerous buildings,resulting in thousands of fatalities and injuries,as well as substantial economic losses.The authors participated in the post-earthquake emergency response as members of the China Search and Rescue Team.During the rescue operations,an investigation into the characteristics of collapsed structures was conducted and the stability of building debris was assessed to ensure the safety of rescue efforts.Subsequently,a rapid seismic safety assessment of affected structures was carried out,including nine city residential blocks,two hospitals,and two apartments.Preliminary analyses indicate that the main causes of structural failure were insufficient cross-sectional dimensions of beams and columns,inadequate stirrup reinforcement,and lack of structural redundancy. 展开更多
关键词 Myanmar earthquake collapsed buildings seismic measures site conditions design code
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Dynamically and economically updating the National Elevation Datum with the assistance of InSAR:A case study in North China Plain
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作者 Wenke Zheng Zhaofeng Du +2 位作者 Xiaomin Zhou Cong Yue Shengtao Qin 《Geodesy and Geodynamics》 2025年第3期310-320,共11页
Land subsidence significantly impacts the accuracy of the National Elevation Datum in China.In order to solve this issue,a dynamic and economical way was proposed to update the National Elevation Datum with the assist... Land subsidence significantly impacts the accuracy of the National Elevation Datum in China.In order to solve this issue,a dynamic and economical way was proposed to update the National Elevation Datum with the assistance of InSAR in the North China Plain,which served as the research area.Moreover,the GNSS result was used to correct the InSAR result for the vertical deformation field,which has a relatively unified deformation reference.By integrating the vertical deformation field with the national elevation control point,an analysis and evaluation of changes in the National Elevation Datum were conducted.In addition,a regional remeasurement scheme was formulated to achieve dynamic updates and mainte-nance of the National Elevation Datum on a regional scale.Through data acquisition and processing,we successfully improved reliability within the main subsidence areas for future use.As a result,updating the elevation values utilize a regional update method,and a dynamic and economical technical process to update the National Elevation Datum is shown in the study. 展开更多
关键词 INSAR Land subsidence National Elevation Datum Dynamic update Regional remeasurement
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Enrichment conditions and metallogenic model of potassium and lithium resources in the Lower–Middle Triassic,northeastern Sichuan Basin,SW China
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作者 SU Kelu ZHONG Jiaai +12 位作者 WANG Wei SHI Wenbin CHEN Zuqing LI Yuping FAN Zhiwei WANG Jianbo LIU Yong PAN Bei LIU Zhicheng JIANG Yanxia LIANG Zirui ZHANG Yuying WANG Fuming 《Petroleum Exploration and Development》 2025年第1期272-284,共13页
Wells CXD1 and CX2 have uncovered high-concentration potassium-and lithium-containing brines and substantial layers of halite-type polyhalite potash deposits within the 4th and 5th members of the Triassic Jialingjiang... Wells CXD1 and CX2 have uncovered high-concentration potassium-and lithium-containing brines and substantial layers of halite-type polyhalite potash deposits within the 4th and 5th members of the Triassic Jialingjiang Formation and the 1st Member of Leikoupo Formation(Jia 4 Member,Jia 5 Member,and Lei 1 Member)in the Puguang area,Sichuan Basin.These discoveries mark significant breakthroughs in the exploration of deep marine potassium and lithium resources within the Sichuan Basin.Utilizing the concept of“gas-potassium-lithium integrated exploration”and incorporating drilling,logging,seismic,and geochemical data,we have investigated the geological and enrichment conditions,as well as the metallogenic model of potassium-rich and lithium-rich brines and halite-type polyhalite.First,the sedimentary systems of gypsum-dolomite flats,salt lakes and evaporated flats were developed in Jia 4 Member,Jia 5 Member,and the 1st member of Leikoupo Formation(Lei 1 Member)in northeastern Sichuan Basin,forming three large-scale salt-gathering and potassium formation centers in Puguang,Tongnanba and Yuanba,and developing reservoirs with potassium-rich and lithium-rich brines,which are favorable for the deposition of potassium and lithium resources in both solid or liquid phases.Second,the soluble halite-type polyhalite has a large thickness and wide distribution,and the reservoir brine has a high content of K+and Li+.A solid-liquid superimposed“three-story structure”(with the lower thin-layer of brine reservoir in lower part of Jia 4 Member and Jia 5 Member,middle layer of halite-type polyhalite potash depositS,upper layer of potassium-rich and lithium-rich brine reservoir in Lei 1 Member)is formed.Third,the ternary enrichment and mineralization patterns for potassium and lithium resources were determined.Vertical superposition of polyhalite and green bean rocks is the mineral material basis of potassium-lithium resources featuring“dual-source replenishment and proximal-source release”,with primary seawater and gypsum dehydration as the main sources of deep brines,while multi-stage tectonic modification is the key to the enrichment of halite-type polyhalite and potassiumlithium brines.Fourth,the ore-forming process has gone through four stages:salt-gathering and potassium-lithium accumulation period,initial water-rock reaction period,transformation and aggregation period,and enrichment and finalization period.During this process,the halite-type polyhalite layer in Jia 4 Member and Jia 5 Member is the main target for potassium solution mining,while the brine layer in Lei 1 Member is the focus of comprehensive potassium-lithium exploration and development. 展开更多
关键词 potassium-lithium resources halite-type polyhalite potassium-rich and lithium-rich brine enrichment mechanism Triassic Jialingjiang Formation Leikoupo Formation Puguang area Sichuan Basin
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Prediction of sandstone porosity in coal seam roof based on variable mode decomposition and random forest method
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作者 Huang Ya-ping Qi Xue-mei +3 位作者 Cheng Yan Zhou Ling-ling Yan Jia-hao Huang Fan-rui 《Applied Geophysics》 2025年第1期197-208,235,236,共14页
Evaluation of water richness in sandstone is an important research topic in the prevention and control of mine water disasters,and the water richness in sandstone is closely related to its porosity.The refl ection sei... Evaluation of water richness in sandstone is an important research topic in the prevention and control of mine water disasters,and the water richness in sandstone is closely related to its porosity.The refl ection seismic exploration data have high-density spatial sampling information,which provides an important data basis for the prediction of sandstone porosity in coal seam roofs by using refl ection seismic data.First,the basic principles of the variational mode decomposition(VMD)method and the random forest method are introduced.Then,the geological model of coal seam roof sandstone is constructed,seismic forward modeling is conducted,and random noise is added.The decomposition eff ects of the empirical mode decomposition(EMD)method and VMD method on noisy signals are compared and analyzed.The test results show that the firstorder intrinsic mode functions(IMF1)and IMF2 decomposed by the VMD method contain the main eff ective components of seismic signals.A prediction process of sandstone porosity in coal seam roofs based on the combination of VMD and random forest method is proposed.The feasibility and eff ectiveness of the method are verified by trial calculation in the porosity prediction of model data.Taking the actual coalfield refl ection seismic data as an example,the sandstone porosity of the 8 coal seam roof is predicted.The application results show the potential application value of the new porosity prediction method proposed in this study.This method has important theoretical guiding significance for evaluating water richness in coal seam roof sandstone and the prevention and control of mine water disasters. 展开更多
关键词 VMD random forest method coal seams SANDSTONE POROSITY
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3D Seismic Data Reconstruction based on Weighted Fast Iterative Shrinkage Thresholding algorithm
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作者 Zhang Hua Qiu Da-Xing +3 位作者 Mo Zi-Fen Hao Ya-Ju Wu Zhao-Qi Dai Meng-Xue 《Applied Geophysics》 2025年第1期22-34,231,232,共15页
Data reconstruction is a crucial step in seismic data preprocessing.To improve reconstruction speed and save memory,the commonly used three-dimensional(3D)seismic data reconstruction method divides the missing data in... Data reconstruction is a crucial step in seismic data preprocessing.To improve reconstruction speed and save memory,the commonly used three-dimensional(3D)seismic data reconstruction method divides the missing data into a series of time slices and independently reconstructs each time slice.However,when this strategy is employed,the potential correlations between two adjacent time slices are ignored,which degrades reconstruction performance.Therefore,this study proposes the use of a two-dimensional curvelet transform and the fast iterative shrinkage thresholding algorithm for data reconstruction.Based on the significant overlapping characteristics between the curvelet coefficient support sets of two adjacent time slices,a weighted operator is constructed in the curvelet domain using the prior support set provided by the previous reconstructed time slice to delineate the main energy distribution range,eff ectively providing prior information for reconstructing adjacent slices.Consequently,the resulting weighted fast iterative shrinkage thresholding algorithm can be used to reconstruct 3D seismic data.The processing of synthetic and field data shows that the proposed method has higher reconstruction accuracy and faster computational speed than the conventional fast iterative shrinkage thresholding algorithm for handling missing 3D seismic data. 展开更多
关键词 data reconstruction fast iterative shrinkage thresholding prior support set weighted operator
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Shift in Translation:A Case Study of Translating NFPA 1 Fire Code into Chinese
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作者 Fang Chen Xinlu Xing Huili Wang 《Journal of Contemporary Educational Research》 2025年第2期1-15,共15页
National Fire codes,mandated by government authorities to tackle technical challenges in fire prevention and control,establish fundamental standards for construction practices.International collaboration in fire prote... National Fire codes,mandated by government authorities to tackle technical challenges in fire prevention and control,establish fundamental standards for construction practices.International collaboration in fire protection technologies has opened avenues for China to access a wealth of documents and codes,which are crucial in crafting regulations and developing a robust,scientific framework for fire code formulation.However,the translation of these codes into Chinese has been inadequate,thereby diminishing the benefits of technological exchange and collaborative learning.This underscores the necessity for comprehensive research into code translation,striving for higher-quality translations guided by established translation theories.In this study,we translated the initial segment of the NFPA 1 Fire Code into Chinese and examined both the source text and target text through the lens of Translation Shift Theory,a concept introduced by Catford.The conclusion culminated in identifying four key shifts across various linguistic levels:lexis,sentences,and groups,to ensure an accurate and precise translation of fire codes.This study offers a through and lucid explanation of how the translator integrates Catford’s theories to solve technical challenges in NFPA 1 Fire Code translation,and establish essential standards for construction translation practices. 展开更多
关键词 Fire code Code document JC Catford Translation shift theory
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Genetic model and resource evaluation of the Guantao Formation thermal reservoir in the Guanxian fault depression,southern Hebei
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作者 Xu Wang Wei Li +3 位作者 Hai-min Wang Dong-yang Zhang Shu-wen Chen Ling-ling Bao 《Applied Geophysics》 2025年第3期698-710,894,共14页
Medium-low temperature geothermal resources are abundant in the Guanxian fault depression.An essential foundation for the effective development and use of geothermal resources is the study of the genetic model and res... Medium-low temperature geothermal resources are abundant in the Guanxian fault depression.An essential foundation for the effective development and use of geothermal resources is the study of the genetic model and resource assessment of the geothermal system.This study examines the geothermal geological circumstances,hydrochemical features,and geothermal field characteristics based on the regional geological structure and prior research findings.The appraisal of geothermal resources is done,and a conceptual model of the geothermal system in the research area is built.The findings indicate that the Guan xian fault depression's geothermal resources are primarily Guantao Formation sandstone heat reservoirs.The geothermal water at the wellhead has a temperature between 54℃and 60℃,and its primary chemistry is Cl·SO_(4)-Na.Deep thermal conduction heats the geothermal water,which is then laterally supplied to the reservoir after being largely restored by air precipitation from the western Taihang Mountains.With an annual exploitable geothermal resource of 6,782×10^(12)J,or 23.14×10^(4)tons of standard coal,the Guantao Formation sandstone reservoir in the Guanxian depression has a geothermal resource of about 620.10×10^(16)J.An area of 18 million m^(2)can be heated by geothermal extraction per year,demonstrating the potential for geothermal resources and their high development and use value. 展开更多
关键词 Guanxian County Fault-Bounded Depression geothermal system sand geothermal reservoir genetic model resource evaluation
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Effectiveness of various chemical leaching systems in the remediation of chromium-contaminated soil and their impact on chromium speciation
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作者 Yuxiao Jiang Chao Hu +3 位作者 Aoyu Zhou Huiyang Qiu Benyi Cao Jian Xu 《Journal of Environmental Sciences》 2025年第11期77-89,共13页
Chemical leaching techniques have been proven effective in removing heavymetal contaminants fromsoil using various leaching agents.Previous research has shown that both singleagent and composite leaching systems have ... Chemical leaching techniques have been proven effective in removing heavymetal contaminants fromsoil using various leaching agents.Previous research has shown that both singleagent and composite leaching systems have been applied for the remediation of chromiumcontaminated soils,with varying degrees of success depending on soil type and contaminant form.However,the removal rate of total chromium(Cr)and hexavalent chromium(Cr(Ⅵ))often fluctuates based on the chemical composition of the leaching agents,as well as the soil’s physicochemical properties,such as pH and Cr speciation stability.Therefore,this study investigates the effectiveness of 20 composite leaching systems,including deionized water,lime water,calcium chloride,sodium carbonate,and sodium phosphate,through soil column leaching tests.The aim was to evaluate their impact on soil pH,total Cr,and Cr(Ⅵ)removal,and to examine the transformation of various Cr species during the leaching process.Results reveal that lime water and sodium phosphate were particularly effective in stabilizing Cr(Ⅵ)and neutralizing soil pH,while total Cr removal amount ranged from 197.4 mg/kg to 1671.6 mg/kg and Cr(Ⅵ)removal amount ranged from 113.2mg/kg to 316.8mg/kg.We also find that using 0.2 mol/L citric acid,0.1 mol/L hydrochloric acid,and 1.2 mL/g lime solution adjusted soil pH to 7.37,with average removal efficiencies of 34.6%.for total Cr and 72.7%for Cr(Ⅵ).Overall,our results suggest that the combined use of lime water and sodium phosphate is an effective strategy for remediating chromium-contaminated soil,particularly for stabilizing unleached Cr and adjusting soil pH. 展开更多
关键词 Chemical leaching techniques Metal contaminants REMEDIATION Removal rate Total chromium Leaching systems
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Late Paleozoic-Mesozoic subduction and accretionary processes of the Tethys in southeastern Gangdese:record of temporal and spatial transitions from the Paleo-Tethys to Neo-Tethys
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作者 Yao Zhong Wen-Guang Yang +7 位作者 Li-Dong Zhu Hong-Liang Zhang Long Xie Yuan-Jun Mai Wei-Na Feng Nan Li Yu Zhou Xia Tong 《Episodes》 2025年第2期213-228,共16页
The Yarlung Zangbo Suture Zone(YZSZ)on the southern margin of the Lhasa block and the Tangjia-Sumdo ultrahigh-pressure metamorphic belt(TSMB)within the block represent natural laboratories for the study of plate tecto... The Yarlung Zangbo Suture Zone(YZSZ)on the southern margin of the Lhasa block and the Tangjia-Sumdo ultrahigh-pressure metamorphic belt(TSMB)within the block represent natural laboratories for the study of plate tectonics and oceanic slab subduction.It is generally believed that these two zones represent the remnants of the ancient oceanic crust and upper mantle of the Yarlung Zangbo Neo-Tethys(YZNT)and the Tangjia-Sumdo Paleo-Tethys(TSPT).However,the evolutionary patterns and spatiotemporal relationships of the TSPT and the YZNT have been debated. 展开更多
关键词 yarlung zangbo suture SUBDUCTION Accretionary Processes TETHYS study plate tectonics oceanic slab subductionit Late Paleozoic Mesozoic oceanic crust
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Spatiotemporal distribution of GNSS-derived PWV in Australia from 2010 to 2019
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作者 Pan Zhao Fuyang Ke +1 位作者 Haopeng Wu Min Wei 《Geodesy and Geodynamics》 2025年第4期454-464,共11页
The weather in Australia is significantly influenced by water vapor evaporated fromwarm ocean surfaces,which is closely associated with various extreme weather events in the region,such as floods,droughts,and bushfire... The weather in Australia is significantly influenced by water vapor evaporated fromwarm ocean surfaces,which is closely associated with various extreme weather events in the region,such as floods,droughts,and bushfires.This study utilizes Precipitable Water Vapor(PWV)data from 15 Global Navigation Satellite System(GNSS)stations spanning 2010 to 2019 to investigate the spatiotemporal distribution of atmospheric water vapor across Australia,aiming to improve the accuracy of forecasting hazardous weather events.The results indicate distinct regional features in the spatial distribution of PWV.PWV gradually decreases from coastal areas toward inland regions and increases from south to north.Temporally,the overall trend of PWV remains consistent.From an annual trend perspective,most areas exhibit a decline in PWV content,with the exception of the southwestern coastal region,which shows an increasing trend.Furthermore,the study explores the correlations between PWV content and elevation,latitude,and longitude.Among these,latitude demonstrates the strongest correlation with PWV,with a correlation coefficient as high as 0.88,highlighting the significant impact of latitude on water vapor distribution. 展开更多
关键词 AUSTRALIA GNSS-derived PWV Spatial distribution characteristics Multi-scale analysis Climate variability
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Origin of the Cretaceous Biluocuo Low-Mg Trachy-Andesites in the Southern Qiangtang Block:Implications for Crust-Mantle Interactions and the Precambrian Basement
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作者 JI Changjun CHEN Chong +3 位作者 ZOU Yuanbing CHEN Yun ZHOU Lianfeng ZHU Jiang 《Acta Geologica Sinica(English Edition)》 2025年第3期761-773,共13页
The Cretaceous andesites were discovered in the Biluocuo area,and provided key records to understand the late Mesozoic geodynamic evolution and crustal basement for the southern Qiangtang block in the central Xizang.I... The Cretaceous andesites were discovered in the Biluocuo area,and provided key records to understand the late Mesozoic geodynamic evolution and crustal basement for the southern Qiangtang block in the central Xizang.In this study,we present a detailed study of zircon U-Pb dating,major and trace elemental composition,and Sr-Nd-Hf isotopes for the Biluocuo trachy-andesites.The trachy-andesites yielded zircon U-Pb ages at ca.97 Ma,and exhibited SiO_(2)contents ranging from 55.92 to 69.04 wt%,low TiO_(2)contents(0.37 to 0.75 wt%)and low Mg~#values(18.6 to 53.7),suggesting that they belong to high-K calc-alkaline series.They showed adakitic signatures,such as high Sr/Y ratios(almost 24 to 55)and low Y(<20 ppm),implying they were generated at great depths(>15 kbar).The samples have initial Sr isotopic ratios of 0.70963 to 0.70964,εNd(t)values of-4.7 to-4.6,and zirconεHf(t)values of-1.2 to+1.3 with two-stage Hf model ages of 0.95 to 1.09 Ga.Elemental and Sr-Nd-Hf isotopic signatures suggest that the trachy-andesites were derived from the partial melting of the thickened lower crust with involvement of metasomatized mantle components.Combined with coeval highMg andesites,we proposed that underplating of mantle induced melting of the lower crust at ca.97 Ma in the southern Qiangtang block,following by lithospheric delamination.Inherited/xenocrystic zircons from the trachy-andesites revealed magmatic activities at 2562 Ma,1850-1804 Ma,1768-1665 Ma,1043-935 Ma,851-736 Ma and 642-540 Ma.There is a Precambrian crustal basement in the southern Qiangtang block,which may have experienced the assembly and break-up of the Columbia,Rodinia,and Gondwana supercontinents. 展开更多
关键词 geochemistry low-Mg adakitc rocks VOLCANIC crust-mantle interaction ancient crust Qiangtang block
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Transient Formation of Stress Granules Disturbs Neural Stem Cell Differentiation
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作者 Mengmeng Wang Yarong Wang +8 位作者 Hongyu Ma Hanze Liu Yating Lu Yaozhong Zhang Zhihui Huang Songqi Dong Kun Zhang Shengxi Wu Yazhou Wang 《Neuroscience Bulletin》 2025年第11期2078-2082,共5页
Dear Editor,Stress granules(SGs)are dynamic membraneless RNAprotein aggregates or organelles that are formed in response to various cellular stresses and disassemble rapidly with the decay of stresses[1].Under stressf... Dear Editor,Stress granules(SGs)are dynamic membraneless RNAprotein aggregates or organelles that are formed in response to various cellular stresses and disassemble rapidly with the decay of stresses[1].Under stressful conditions,protein translation is often inhibited suddenly.The resulting untranslated messenger ribonucleoproteins interact with the so-called"nucleator proteins"(such as G3BP1/2 and TIA1)to form the core structure of SGs,which then grow or merge into mature SGs by sequestering untranslated mRNAs and misfolded proteins[2,3]. 展开更多
关键词 transient formation protein translation untranslated messenger ribonucleoproteins rnaprotein aggregates stress granules cellular stresses sequestering untranslated mrna neural stem cell differentiation
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Zircon U-Pb Ages and Sr-Nd-Hf Isotopes Geochemistry of I-Type Granites in the Jiangda-Weixi Region,Eastern Xizang:Implications for the Tectonic Evolution of the Paleo-Tethyan Orogen
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作者 Rui Gao Tao Wu +3 位作者 Andrew C.Kerr Han Liu Long Xiao Wan Huang 《Journal of Earth Science》 2025年第6期2387-2410,共24页
Permian—Triassic granitoids are widely distributed along the Jinshajiang suture belt,eastern Xizang,and are regarded as the result of the tectonic-magmatic activity associated with the evolution of Paleo-Tethys Ocean... Permian—Triassic granitoids are widely distributed along the Jinshajiang suture belt,eastern Xizang,and are regarded as the result of the tectonic-magmatic activity associated with the evolution of Paleo-Tethys Ocean.This paper focuses on the high-K calc-alkaline I-type Rennong(~235 Ma)and Jiaduoling(~232 Ma)granitoid plutons,eastern Xizang,which are enriched in light rare earth elements(LREEs)and large ion lithophile elements(LILEs),but depleted in high field strength elements(HFSEs)with moderate-weak negative Eu anomalies(0.61–0.90).The Rennong granites are characterized by uniform zircon ε_(Hf)(t)values(-7.3 to-3.5)and negative ε_(Nd)(t)values(-7.6 to-5.7),with old two-stage Nd model ages(T_(DM2)=1.51-1.46 Ga)and was likely formed by partial melting of the basement rocks,whereas the Jiaduoling rock samples have variable zircon ε_(Hf)(t)values(-5.7 to+5.5)but negativeεNd(t)values(-7.6 to-7.7)and are proposed to be formed by hybridization of mantle-derived mafic magma,Rennong felsic magma and sediments.Mafic microgranular enclaves(MMEs)in the Jiaduoling granitic rocks,have similar zircon U-Pb ages(~237 Ma)and zircon ε_(Hf)(t)values(-4.4 to+6.3)to the host rocks,indicating that zircons in the MMEs were actually xenocrysts that formed at an early stage in the granitic magma chamber.These results reveal that the break-off of the Jinshajiang oceanic slab beneath Changdu(Qamdo)-Simao Block was in a post-collisional setting,resulted in the upwelling of asthenosphere in the Late Triassic,and then,generated the wide-spread intermediate-felsic magmatism along the Jinshajing belt,including the Rennong and Jiaduoling plutons. 展开更多
关键词 Paleo-Tethys Ocean Jiangda(Jomda)-Weixi Sr-Nd-Hf isotopes I-type granite GEOCHRONOLOGY GEOCHEMISTRY
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First SHRIMP Zircon U-Pb Dating Constraints for the Ediacaran Wenghui Biota
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作者 Mingsheng Zhao Feng Tang +4 位作者 Giovanni Mussini Yulan Li Heng Zhang Jianshu Chen Linzhi Gao 《Journal of Earth Science》 2025年第1期102-112,共11页
The Ediacaran Period records a significant turning point in the evolution of life on Earth,witnessing the rise to ecological dominance of macroscopic tissue-grade organisms.The Wenghui biota from the Doushantuo Format... The Ediacaran Period records a significant turning point in the evolution of life on Earth,witnessing the rise to ecological dominance of macroscopic tissue-grade organisms.The Wenghui biota from the Doushantuo Formation of South China hosts abundant multicellular algal macrofossils and problematica,some of which might be closely related to taxa from classic Late Ediacaran assemblages from South Australia and the White Sea biota of Russia.However,a lack of well-resolved isotopic age estimates has hampered efforts to constrain the timing of appearance of the Wenghui biota,obfuscating its significance to our understanding of Ediacaran macroevolution in the aftermath of the Snowball Earth events.Here,we present the first SHRIMP zircon U-Pb dating results for samples obtained from a laminated tuff ash layer at the base of the Wenghui biota in the Doushantuo Formation,Jiangkou County,Tongren City,Guizhou Province,China.Our analyses yield an age of 595.4±5.3 Ma for the first appearance of Wenghui biota,suggesting that its appearance postdated that of the Lantian and Weng'an biotas,but preceded that of the Miaohe biota.These newly obtained age proxies offer an independent test of previous isotopic estimates for the age of the Wenghui biota,providing new chronostratigraphic evidence to map the succession of Ediacaran fossil assemblages on the Yangtze Platform during the Doushantuo interval.These data suggest that the Lantian,Weng'an,Wenghui,and Miaohe biotas may record a sequence of biotic assemblages attesting to successive phases in the radiation of Ediacaran macroscopic organisms,particularly macroalgae. 展开更多
关键词 ZIRCON SHRIMP U-Pb dating Wenghui biota Doushantuo Formation Ediacaran system southern China
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Seasonal Effects of Air Pollutants on Stroke Deaths in Qingdao from 2014 to 2019
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作者 Jingkai Zhang Bingling Wang +9 位作者 Lu Pan Nan Ge Jingya Yin Yuan Fang Hua Zhang Jianjun Zhang Xiutao Cao Yan Ma Li Cheng Haiping Duan 《Biomedical and Environmental Sciences》 2025年第7期885-890,共6页
Stroke is the third-leading cause of disabilityadjusted life years(DALYs)and poses a significant public health challenge worldwide~([1]).Developing countries,including China,continue to face a substantial burden from ... Stroke is the third-leading cause of disabilityadjusted life years(DALYs)and poses a significant public health challenge worldwide~([1]).Developing countries,including China,continue to face a substantial burden from stroke.Since 1990,China has reported the highest global stroke burden,with 2.19 million deaths and 45.9 million DALYs recorded in 2019~([2]). 展开更多
关键词 seasonal effects developing countries public health challenge Qingdao stroke deaths air pollutants China disability adjusted life years
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A Coarse to Fine Thin Cloud Removal Network with Pyramid Non-local Attention
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作者 GUAN Wang TIAN Zhenkai +5 位作者 MA Tao ZHAO Lingyuan XIE Shizhe YAN Jin DU Yang ZOU Yunkun 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期589-600,共12页
In remote sensing imagery,approximately 67%of the data are affected by cloud cover,significantly increasing the difficulty of image classification,recognition,and other downstream interpretation tasks.To effectively a... In remote sensing imagery,approximately 67%of the data are affected by cloud cover,significantly increasing the difficulty of image classification,recognition,and other downstream interpretation tasks.To effectively address the randomness of cloud distribution and the non-uniformity of cloud thickness,we propose a coarse-to-fine thin cloud removal architecture based on the observations of the random distribution and uneven thickness of cloud.In the coarse-level declouding network,we innovatively introduce a multi-scale attention mechanism,i.e.,pyramid nonlocal attention(PNA).By integrating global context with local detail information,it specifically addresses image quality degradation caused by the uncertainty in cloud distribution.During the fine-level declouding stage,we focus on the impact of cloud thickness on declouding results(primarily manifested as insufficient detail information).Through a carefully designed residual dense module,we significantly enhance the extraction and utilization of feature details.Thus,our approach precisely restores lost local texture features on top of coarse-level results,achieving a substantial leap in declouding quality.To evaluate the effectiveness of our cloud removal technology and attention mechanism,we conducted comprehensive analyses on publicly available datasets.Results demonstrate that our method achieves state-of-the-art performance across a wide range of techniques. 展开更多
关键词 channel attention thin cloud removal network pyramid non-local attention(PNA) remote sensing image residual dense connection
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Magmatic Processes of the Lingshan Granitic Batholith in the Dabie Orogen,Central China:Insights into Dabie-Type Porphyry Mo Mineralization
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作者 Jiang Zhu Zhanke Li +5 位作者 Guohu Wang Xianbin Shi Yang Wang Chao Chen Song Chen Yuanbing Zou 《Journal of Earth Science》 2025年第5期2075-2093,共19页
Dabie-type porphyry Mo deposits were proposed as a new type of porphyry Mo deposits,and had unique geological characteristics.It is still poorly understood about the magmatic processes that led to the Dabie-type Mo mi... Dabie-type porphyry Mo deposits were proposed as a new type of porphyry Mo deposits,and had unique geological characteristics.It is still poorly understood about the magmatic processes that led to the Dabie-type Mo mineralization.Here,we present zircon U-Pb and Lu-Hf isotopic,whole-rock and biotite elemental,and whole-rock Sr-Nd isotopic analyses on the Lingshan granitic batholith in the Dabie Orogen.It consists of three units(ⅠtoⅢ)that were emplaced before,genetically accompanied with,and after the Mo mineralization.LA-ICP-MS zircon U-Pb dating yielded crystallization ages of 128.2±1.0 Ma(MSWD=1.14)for UnitⅠand ages of 127.8±1.2 Ma(MSWD=0.28)and 126.6±1.8 Ma(MSWD=1.6)for UnitⅡ,indicating that they were emplaced during 130 to 125 Ma.The granites have high SiO_(2)contents(75.84 wt.%to 78.94 wt.%)and low MgO contents(0.07 wt.%to 0.10 wt.%),and are classified as fractionatedⅠ-type granite.UnitsⅠandⅡhave similar Sr-Nd isotopic ratios(ε_(Nd)(t)=-16.2 to-17.2,(^(87)Sr/^(86)Sr)_(i)=0.70540 to 0.70692)and zirconε_(Hf)(t)values(-17.4 to-20.4),indicating they were derived from partial melting of the ancient Yangtze lower crust.Mo mineralized granite from UnitⅡis characterized by the lower oxygen fugacity,fluorine enrichment and high fractionation.Magmas of unitsⅠandⅡhave experienced fractional crystallization,with the assimilation of supracrustal materials that account for the increased TiO_(2),F and Mo contents,and the decreased fO_(2).We proposed that the assimilation in upper-crustal magmatic processes plays key factors for magmatic systems that led to the Dabie-type porphyry Mo deposits. 展开更多
关键词 granite crustal assimilation oxygen fugacity porphyry Mo deposit Dabie Orogen mineral deposits
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Tracing Metal Sources of Geogas with Lead Isotopes:A Case Study on the Bairendaba Silver-polymetallic Deposit,Inner Mongolia
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作者 FAN Huihu ZUO Libo +4 位作者 WAN Wei WANG Mingqi QI Fuyong GAO Yuyan ZHANG Bimin 《Acta Geologica Sinica(English Edition)》 2025年第6期1776-1787,共12页
Geogas survey is an unconventional geochemical prospecting method that has proven particularly effective in exploring concealed ore deposits.However,its application in covered areas has been questioned due to the lack... Geogas survey is an unconventional geochemical prospecting method that has proven particularly effective in exploring concealed ore deposits.However,its application in covered areas has been questioned due to the lack of a confirmed geogas formation mechanism.Investigating the sources of geogas anomalies can help clarify this mechanism.This study focuses on the Bairendaba silver-polymetallic deposit,located in a grassland-covered area.Tracer research was conducted on lead isotope compositions in the mining area by analyzing various solid media(soil,rocks,ores)and geogas samples.The results revealed considerable differences in lead isotope compositions between background geogas samples and solid media.Furthermore,the lead isotope compositions of anomalous geogas samples differed markedly from those of background samples.These anomalous samples are located closer to the ore body,suggesting that ore-derived lead is incorporated into the geogas.The anomalous lead in geogas is inferred to originate from deep,concealed ore bodies.This study provides a theoretical basis for applying geogas surveys in mineral exploration within covered terrains. 展开更多
关键词 geogas survey lead isotope metal sources of geogas Bairendaba silver-polymetallic deposit
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Relations of Uranium Enrichment and Carbonaceous Debris within the Daying Uranium Deposit, Northern Ordos Basin 被引量:13
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作者 Fan Zhang Yangquan Jiao +2 位作者 Liqun Wu Hui Rong Longhui Wang 《Journal of Earth Science》 SCIE CAS CSCD 2019年第1期142-157,共16页
Carbonaceous debris(CD)is widely distributed in the sandstone of the Daying Uranium Deposit,northern Ordos Basin,and coexists with uranium minerals,which provides a favorable case for studying their relationship.Vitri... Carbonaceous debris(CD)is widely distributed in the sandstone of the Daying Uranium Deposit,northern Ordos Basin,and coexists with uranium minerals,which provides a favorable case for studying their relationship.Vitrinite reflectance(VR),macerals,moisture,volatile matter,ash,total sulfur(S_t)and uranium concentration of CD within the sandstone were studied.The results show that VR ranges from 0.372%Ro to 0.510%Ro with an average value of 0.438%Ro,indicating that CD is in the stage of lignite.The contents of vitrinite(V),inertinite(I)and minerals range from 83.18%–99.48%,0–7.70%,and 0.34%–15.72%,respectively,with the corresponding average value of 95.51%,1.34%,and 3.15%,respectively which indicates that V is the major maceral.Moisture on air dried basis(M_(ad)),volatile matter yield on dry,ash-free basis(V_(daf)),ash yield on dried basis(A_d)and S_t mostly range from 7.95%–16.09%,44.70%–66.54%,4.84%–26.24% and 0.24%–1.12%,respectively,while their average values are 12.43%,53.41%,16.57% and 0.77%,respectively.It suggests that CD is of medium-high moisture,super-high volatile matter,low-medium ash and low sulfur.Uranium concentration ranges from 29 ppm to 92 ppm with an average value of 50 ppm,and uranium concentration increases with the decreased distance to CD.On the whole,M_(ad )and V_(daf) decrease with increasing burial depth,which indicates that CD experienced the burial metamorphism.However,M_(ad) and V_(daf) obviously decrease in uranium-rich areas whereas A_d and S_(t )noticeably increase.Comprehensive studies suggest that there is a certain relationship between uranium enrichment and CD.CD in the stage of lignite helps the adsorption of uranium.On one hand,radioactivity uranium enrichment makes organic matter maturation increase with a decrease in moisture and volatile matter.On the other hand,an increase in organic matter maturation,caused by radioactivity uranium enrichment,results in an increase in uranium minerals,which is instructive in the study of regional uranium mineralization and metallogenic regularity. 展开更多
关键词 CARBONACEOUS DEBRIS coal property parameters Daying URANIUM DEPOSIT ORDOS Basin
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Groundwater hydrochemistry and isotope geochemistry in the Turpan Basin, northwestern China 被引量:18
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作者 Lu CHEN GuangCai WANG +2 位作者 FuSheng HU YaJun WANG Liang LIU 《Journal of Arid Land》 SCIE CSCD 2014年第4期378-388,共11页
The Turpan Basin is located in the arid zone of northwestern China and is a typical closed inland basin surrounded by high mountains. It is one of the most arid regions in the world and, as a result, the groundwater i... The Turpan Basin is located in the arid zone of northwestern China and is a typical closed inland basin surrounded by high mountains. It is one of the most arid regions in the world and, as a result, the groundwater in this area is very important for both domestic and agricultural uses. In the present study, the relationships of major elements(K+, Na+, Ca2+, Mg2+, HCO3-, SO42- and Cl-) and environmental isotopes(δ18O, δ2H and T) in groundwater were analyzed to investigate the evolution of the regional hydrochemistry within the Turpan Basin. The hydrochemistry results demonstrate that groundwater with high total dissolved solids(TDS) concentration is dominated by sodium chloride(Na-Cl) and sodium sulfate(Na-SO4) type water, whereas that with low TDS concentration(typically from near mountain areas) is dominated by calcium bicarbonate(Ca-HCO3) type water. The evolution of groundwater hydrochemistry within the Turpan Basin is a result of calcium carbonate precipitation, evaporation concentration, cation exchange and dissolution of evaporites(i.e. halite, mirabilite and gypsum). Furthermore, evaporite dissolution associated with irrigation practice plays a key role in the groundwater salinization, especially in the central part of the basin. Environmental isotopes reveal that the groundwater is recharged by precipitation in the mountain areas and fast vertical infiltration of irrigation return flow. In the southern sub-basin the shallow groundwater and the deep groundwater is separated at a depth of about 40 m, with substantial differences in terms of hydrochemical and isotopic characteristics. The results are useful for decision making related to sustainable water resource utilization in the Turpan Basin and other regions in northwestern China. 展开更多
关键词 HYDROCHEMISTRY environmental isotopes groundwater salinization evaporite dissolution Turpan Basin
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