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Application of Detrital Apatite U-Pb Geochronology and Trace Elements for Provenance Analysis,Insights from a Study on the Yarlung River Sand

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Journal of earth Science 2024年第4期35卷 1118-1129页

作者： Yufeng Du Guangwei Li Danyang Liu Xianyan Wang Dongxu Cai Xiaolu Dong Qi Yu State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China school of geography and Ocean Nanjing UniversityNanjing210023China

Detrital U-bearing minerals(e.g.,zircon,apatite)U-Pb ages with specific trace-element geochemistry,are frequently used in provenance *** this study,we focus on the Yarlung River drainage in South Tibet,characterized by two distinct lithologic units:The Gangdese batholith to the north(mainly granitoids)and the Tethyan Himalaya(mainly sedimentary rocks)to the south,which plays a crucial role in the erosion of the Tibetan *** constrain the provenance of the Yarlung River Basin,we performed trace-element and U-Pb age analyses of detrital apatite from the river sands of the Yarlung River and its *** findings indicate that the detrital apatite U-Pb age patterns of the north tributaries exhibit main peaks at approximately 40 and 60 Ma,consistent with the corresponding U-Pb age patterns of detrital zircon ***,their trace element casts fall mainly in the Type I granite region,also indicating the Gangdese arc-dominated ***,those of the south tributaries(∼60–20 Ma)exhibit a different age distribution from the detrital zircon U-Pb groups(∼110–150,∼500,and 1100 Ma),suggesting that the detailed apatite U-Pb signals can provide excellent constraints on the provenance of igneous and metamorphic rock sources but less so for sedimentary rock *** with previous detrital zircon data in the study area,our detrital apatite information can highlight young metamorphic events from a complex background(i.e.,Niyang and Nianchu rivers),which offers additional constraints on the provenance of the Yarlung River ***,a combination of geochemistry and geochronology of multi-detrital heavy minerals,such as zircon and apatite,can provide powerful tools for provenance analysis.

关键词： apatite detrital apatite U-Pb age trace elements provenance analysis Yarlung River Tibetan Plateau geochronology

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The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul B.Wignall David P.G.Bond school of earth & Environment University of Leeds school of Environmental sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

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Spatiotemporal mapping of(ultra‐)mafic magmatic mine areas:Implications of economic and political realities in China

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Deep Underground Science and Engineering 2024年第1期3卷 91-102页

作者： Heling Li Liang Tang Tim T.Werner Zhengmeng Hou Fan Meng Jingjing Li College of earth sciences Chengdu University of TechnologyChengduChina Institute of Subsurface Energy Systems Clausthal University of TechnologyClausthal ZellerfeldGermany school of geography Earth and Atmospheric SciencesFaculty of ScienceThe University of MelbourneMelbourneVictoriaAustralia

The spatiotemporal extension/expansion of mine areas is affected by multiple *** far,very little has been done to examine the interaction between mine areas and political or economic ***(ultra‐)mafic magmatic mines in China played a specific role in supporting national development and providing an ideal research subject for monitoring their *** this study,remote sensing and mining‐related GIS data were used to identify and analyze 1233(ultra‐)mafic magmatic mine area polygons in China,which covered approximately 322.96 km2 of land and included a V–Ti–Fe mine,a copper–nickel mine,a chromite mine,an asbestos mine,and a diamond *** was found that(1)the areal expansion of mines is significantly related to the mine types,perimeter,topography,and population density.(2)The mine area variation also reflects market and policy *** temporal expansion of the mine area from 2010 to 2020 followed an S‐shaped pattern(with the turning point occurring in 2014),closely related to iron overcapacity and tightened mining policies.(3)The complexity(D)of the mine area may reflect mine design and excavation *** be specific,lower D indicates early‐stage or artisanal/small‐scale mining,whereas higher D represents large‐scale *** study demonstrates that the detailed mapping of mine land can serve as an indicator to implement miningrelated market and policy ***(ultra‐)mafic mines area data set can be accessed at https://***/record/7636616#.Y-p0uXaZOa0.

关键词： complexity mine area mining and socioeconomic interaction spatiotemporal distribution (ultra‐)mafic magmatic mine

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Factors determining changes in the network of marked hiking trails in the Sudetes

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Journal of Mountain Science 2024年第4期21卷 1075-1099页

作者： Krzysztof KOŁODZIEJCZYK Department of Regional geography and Tourism Institute of Geography and Regional DevelopmentFaculty of Earth Sciences and Environmental ManagementUniversity of WroclawNo.1Uniwersytecki Square50-137 WroclawPoland

Hiking trails are a basic type of tourist infrastructure,which,on the one hand,make areas available for tourist traffic,and on the other hand,can contribute to the protection of the natural environment(if they are well designed and maintained).Owing to the variety of performed functions,their designation is determined by several factors:natural,technical,economic,*** of trails change *** aim of this article is to determine exactly what factors influence transformations within the hiking trail networks and what is their *** this end,three study areas in the Sudetes were analysed:one on the Polish side of the Sudetes-the Table(Stołowe)Mountains,and two on the Czech side-the rock town near the village of Sloup vČechách and the central part of Zlatohorská*** analysis of changes in the shape of the networks over time was carried out,as well as surveys of institutions that were responsible for or influenced these *** areas are characterised by a significant level of changes in the trail *** the factors influencing these changes,the tourist attractiveness of the area,the resilience of the environment,the intensity of tourism traffic,the environmental transformations associated with it,the history of tourism development and land ownership changes should be considered the most *** each stage of forming networks,the key factor should be tourists’needs,including the desire to escape the urbanised *** this reason,trails should avoid roads with artificial(hard)surfaces and heavy automobile traffic.

关键词： Hiking trails Trail networks Graphs Tourist traffic Sudetes

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Pumping-induced Well Hydraulics and Groundwater Budget in a Leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 477-490页

作者： ZHUANG Chao LÜChenyang YAN Long LI Yabing ZHOU Zhifang WANG Jinguo DOU Zhi Walter A.ILLMAN school of earth sciences and Engineering Hohai UniversityNanjing 211100China school of geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTU.K. Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Department of earth and Environmental sciences University of WaterlooOntario N2L 3G1Canada

In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(K)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous K or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct K or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical *** investigations reveal that a low-K interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard *** of low-K or high-S_(s) interlayers also significantly impact well hydraulics and groundwater *** the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer *** using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to calculate aquitard depletion and unconfined aquifer leakage.

关键词： hydrogeology aquitard vertical heterogeneity semi-analytical solution well hydraulics groundwater budget

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Provenance of the Lower Jurassic pyroclastic sediments in the Zigui Basin:Implication for crustal thickening in the eastern Qinling orogenic belt

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Science China earth sciences 2024年第1期67卷 196-207页

作者： Rong CHAI Jianghai YANG Yuansheng DU Chengshan WANG school of earth sciences and Resources China University of Geosciences(Beijing)Beijing 100023China school of earth sciences China University of Geosciences(Wuhan)Wuhan 430074China Chinese Academy of Geological sciences Beijing 100037China

The Late Triassic witnessed significant collisional orogenic events in the Qinling orogenic belt,accompanied by magma underplating and tectonic *** processes potentially resulted in substantial crustal thickening and uplift of the Qinling ***,due to the absence of igneous rock records from this period in the eastern section of the Qinling orogen,the changes in crustal thickness during this orogenic process have not been thoroughly investigated.A series of foreland basins emerged during the Early Mesozoic to the south of the East Qinling orogenic *** basins have preserved clastic sedimentary rocks derived from the uplift and erosion of the orogenic *** sedimentary records serve as crucial records to reconstruct the evolutionary history of the Qinling *** further clarify the collisional orogenic process of the Qinling orogenic belt,this study conducted in situ volcanic lithic fragment geochemistry,detrital zircon U-Pb chronology and trace element composition analysis on the sandstones of the Lower Jurassic Tongzhuyuan Formation in the Zigui *** results suggest that the sandstones,which exhibit a significant abundance of volcanic lithic fragments,has a characteristic detrital zircon age group of 250–200 Ma,indicating a major provenance from the Triassic volcanic *** with regional correlation and paleocurrent analysis,the detrital zircon U-Pb age data show that the source area of volcanic rocks should be in the Qinling orogenic belt to the north of the *** interpretation is further supported by the Triassic granitic rocks exposed in the western part of the orogenic belt,representing the magmatism during the Triassic collisional orogenesis in the Qinling *** on the co-varying relationships between present-day crust thickness with the chemical compositions of granite rocks and zircons,the La/Yb ratio of volcanic lithic fragments in the Tongzhuyuan Formation and the Eu/Eu*ratio of detrital zircon

关键词： Qinling orogenic belt Zigui Basin Late Triassic Detrital zircons Crustal thickening

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Study on the spatial and temporal evolutionary characteristics of ozone concentration and the impact of human activities in China in 2019

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Acta Geochimica 2024年第5期43卷 985-995页

作者： Yongchun Wang Wang Zhang Yu'an Liu Yazhu Wang Yuting Fu Zhaohui Feng Lingqing Wang school of geography South China Normal University College of Urban and Environmental sciences Hunan University of Technology Nanjing Institute of geography and Limnology Chinese Academy of Sciences Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences

Ozone （O3） pollution has a profound impact on human health,vegetation development,and the ecological environment,making it a critical focus of global academic *** recent years,O3pollution in China has been on a steady rise,with ozone emerging as the sole conventional pollutant to consistently increase in concentration without any *** study conducted a quantitative analysis of O3concentrations across 367 Chinese cities in 2019,examining spatial autocorrelation and local clustering of O3levels,and investigated the diverse relationships between human activity factors and *** seasonal fluctuation of O3exhibited the“M-type”pattern,with peak concentrations in winter and the lowest levels in *** center of O3pollution migrated southeastward,with the area of highest concentration progressively shifting south along the eastern ***,O3concentration showed a strong positive correlation with population density,road freight volume,and industrial emissions,suggesting that human activities,vehicle emissions,and industrial operations are significant contributors to *** results provide comprehensive information on the characteristics,causes,and occurrence mechanism of O3in Chinese cities that can be utilized by global government departments to formulate strategies to prevent and control O3pollution.

关键词： Human activities Ozone concentration Spatial heterogeneity Urban agglomerations

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Spatial-temporal patterns and evolution of carbon storage in China's terrestrial ecosystems from 1980 to 2020

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Science China earth sciences 2024年第10期67卷 3270-3287页

作者： Shaojian WANG Shijie ZHOU Chuanglin FANG school of geography and Planning Sun Yat-sen University Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences

Analyzing the changes in carbon storage in terrestrial ecosystems caused by land use changes is a crucial part of exploring the carbon cycle. In addition, enhancing carbon storage in terrestrial ecosystems is an effective and environmentally friendly measure to sequester anthropogenic carbon emissions, which is significant for achieving carbon neutrality and curbing global climate change. This paper uses land use data and carbon density tables with the In VEST model to obtain a carbon storage distribution map of China. It further applies land use response elasticity coefficients, Theil index multi-stage nested decomposition, and spatial autocorrelation analysis to examine the spatial-temporal patterns, causes of changes, and evolution characteristics of carbon storage in terrestrial ecosystems from 1980 to 2020. The results show that the temporal changes in China's carbon storage generally present an inverted S-curve, with an initial rapid decline followed by a slower decrease. Spatially, it features high levels in the northeast, low levels in the northwest, and a uniform distribution in the central and southern *** disturbance of land use type changes on terrestrial ecosystem carbon storage has been effectively mitigated. The significant reduction in grassland area in the Southwest region is the main source of carbon storage loss during the study period, and the encroachment of construction land on arable land in large urban agglomerations is one of the important causes of carbon storage loss. The Theil index multi-stage nested decomposition results indicate that the overall difference in carbon storage in China has decreased, while differences among cities within provinces and among counties within cities have increased. The influence of natural factors on the distribution of carbon storage is weakening, whereas the impact of human activities is becoming more profound, enhancing its influence on the spatial distribution of carbon storage in China. From 198

关键词： Terrestrial ecosystem carbon storage Carbon density Land use change InVEST model Spatiotemporal pattern

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Mineral Chemistry,Trace Elements,Isotopic Analysis and Zircon U-Pb Dating in the Hesar Pluton,Northern UDMA,Iran:Implications for Pre-Collisional Magma Mixing

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 657-678页

作者： Kazem KAZEMI Soroush MODABBERI Parisa GHARIBNEJAD XIAO Yilin Fatemeh SARJOUGHIAN Ali KANANIAN school of Geology College of ScienceUniversity of TehranTehranIran Research Centre for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Department of Geochemistry and Environmental sciences School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Department of earth and sciences Faculty of SciencesUniversity of KurdistanSanandajIran Department of Science Education Farhangian UniversityTehranIran

The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were *** is suggested that the rocks are metaluminous(A/CNK=1.32-1.45),subduction-related I-type calc-alkaline gabbro to diorite with similar mineral assemblages and geochemical *** host rocks yielded an U-Pb crystallization age of 37.3±0.4 Ma for *** have relatively low SiO_(2) contents(52.9-56.6 wt%)and high Mg^(#)(49.8-58.7),probably reflecting a mantle-derived ***-and mantle-normalized trace element patterns are characterized by LREE and LILE enrichment,HREE and HFSE depletion with slight negative Eu anomalies(Eu/Eu^(*)=0.86-1.03).The host rocks yield(^(87)Sr/^(86)Sr)_(i) ratios of 0.70492-0.70510,positive ε_(Nd)(t)values of+1.55-+2.06 and T_(DM2)of 707-736 Ma,which is consistent with the associated mafic microgranular enclaves((^(87)Sr/^(86)Sr)_(i)=0.705014,ε_(Nd)(t)=+1.75,T_(DM2)=729 Ma).All data suggest magma-mixing for enclave and host rock formation,showing a complete equilibration between mixed-mafic and felsic magmas,followed by rapid *** T_(DM1)(Nd)and T_(DM2)(Nd)model ages and U-Pb dating indicate that the host pluton was produced by partial melting of the lower continental crust and subsequent mixing with injected lithospheric mantlederived magmas in a pre-collisional setting of Arabian-Eurasian *** composition indicates a crystallization temperature of~1000℃ and a depth of~9 km.

关键词： enclave magma mixing zircon U-Pb dating Urumieh-Dokhtar magmatic arc

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Spatiotemporal changes in sunshine duration and its influential factors in Chongqing,China from 1961 to 2020

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Journal of Mountain Science 2024年第6期21卷 2005-2024页

作者： LI Jun XIA Hongxuan JIANG Jinge XU Weifeng WEN Di XU Junfeng College of geography and Tourism Chongqing Normal UniversityChongqing 401331China Key Laboratory of GIS Application of Chongqing Chongqing 401331China Chongqing Key Laboratory of earth Surface Processes and Environmental Remote Sensing in Three Gorges Reservoir area Chongqing 401331China Institute of Remote Sensing and earth sciences School of Institute of Remote Sensing and Earth SciencesSchool of ScienceHangzhou Normal UniversityHangzhou 311121China

The surface solar radiation in most parts of the world has undergone a phenomenon known as global dimming and brightening,characterized by an initial decrease followed by an *** a result,the sunshine duration(SD)has decreased in the past 60 *** the backdrop of global dimming and brightening,SD has decreased to varying degrees in many regions of *** the observed data of SD,cloud amount(total cloud amount and low cloud amount,abbreviated as TCA and LCA),precipitation,and relative humidity(RH)from 34 meteorological stations in Chongqing during the period of 1961-2020,along with a digital elevation model(DEM)with a resolution of 90 m,this study analyzed the spatiotemporal variations and influencing factors of *** analysis employed methods such as linear regression,Mann-Kendall test,wavelet transformation,and DEM-based possible SD distributed *** results showed that the annual SD in Chongqing has significantly decreased over the last 60 years,with a decreasing interannual trend rate(ITR)of 40.4 h/*** for no obvious trend in spring,SD decreased significantly in summer,autumn and winter at the ITR of 21.1 h/10a,8.5 h/10a and 7.5 h/10a,*** abrupt decrease in the annual SD was found in *** difference before and after the abrupt decrease was 177.7 *** difference before and after the abrupt decrease was 177.7 *** annual SD possessed the oscillation period of *** spatial heterogeneity of the mean annual SD during the last 60 years was *** distribution of SD in Chongqing is high in the northeast and low in the *** addition,about 73%of the total area in Chongqing showed a significant and very significant decreasing *** regions with significant changes are mainly concentrated in the regions with altitudes of 200~1000 *** increasing LCA was the main cause of the decrease of the annual SD in the regions with 200-400 m altitude decreased the most and changed the *** LCA is the prim

关键词： Sunshine duration Spatiotemporal changes Mann-Kendall test Wavelet analysis Geodetector model

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