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Pre-Cryogenian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China earth Sciences 2024年第4期67卷 899-918页

作者： Peiyuan HU Qingguo ZHAI Guochun ZHAO Peter A.CAWOOD Yue TANG Yiming LIU Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China department of earth Sciences University of Hong KongPokfulam RoadHong Kong 999077China State Key Laboratory of Continental dynamics Department of GeologyNorthwest UniversityXi’an 710069China School of earth Atmosphere&EnvironmentMonash UniversityMelbourneVIC 3800Australia

The composition and geological evolution of pre-Cryogenian material in the Tibetan Plateau and its surrounding areas have played an important role in studying the formation and evolution of early supercontinents on *** paper systematically summarizes the characteristics of pre-Cryogenian sedimentation,paleontology,magmatism,and metamorphism in the Tibetan Plateau and its surrounding *** on existing data,the records of pre-Cryogenian sedimentation and paleontology are mainly concentrated in the Meso-Neoproterozoic,with relatively few records from the Paleoproterozoic or *** oldest geological record is the Hadean detrital zircons in the metamorphosed sedimentary rocks of the Himalaya and Qamdo areas(ca.4.0 Ga).The Tibetan Plateau and surrounding areas preserve records related to the formation and evolution of the Kenor supercraton,and the Columbia,Rodinia,and Gondwana ***-Cryogenian basements can be divided into three types:Tarim-,Yangtze-,and *** Tarim-type basement has a paleogeographic affinity with the northern margins of the Australian and Indian continents and lacks detrital zircon age peaks and magmatic-metamorphic records related to the Rodinia assembly(ca.1.3-0.9 Ga).The Yangtze-type basement records volcanic activity related to global cooling in the latest pre-Cryogenian period and contains Meso-Neoproterozoic stromatolite and micropaleoflora fossils,as well as magmaticmetamorphic records related to Rodinia assembly(ca.1.1-1.0 Ga).The Lhasa-type basement is characterized by Neoproterozoic rift-related sediment records(ca.900 Ma)and high-pressure metamorphic events(ca.650 Ma),with a prominent peak of detrital zircon ages of ca.1.2-1.1 *** is likely to have a paleogeographic affinity with the African continent.

关键词： Tibetan Plateau Pre-Cryogenian Sedimentation Fossils Paleogeographic evolution

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Unstable evolution of railway slope under the rainfall-vibration joint action

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Journal of Mountain Science 2024年第4期21卷 1419-1431页

作者： DONG Haoyu WANG Jiading ZHANG Dengfei LI Lin XU Yuanjun State Key Laboratory of Continental dynamics Department of GeologyNorthwest UniversityXi’an 710069China

Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of ***,as two major factors affecting the stability of railway slopes,few scholars have explored the unstable evolution of railway slopes under the joint action of *** on the model test of sandy soil slope,the unstable evolution process of slope under locomotive vibration,rainfall,and rainfall-vibration joint action conditions was simulated in this *** comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions,the change laws of pore pressure under the influence of vibration and rainfall were *** main control factors affecting the stability of slope structure under the joint action conditions were further *** with the slope failure phenomena under these three conditions,the causes of slope instability resulting from each leading factor were ***,according to the above conclusions,the unstable evolution of the slope under the rainfall-vibration joint action was *** test results show that the unstable evolution process of sandy soil slope,under the rainfall-vibration joint action,can be divided into:rainfall erosion cracking,vibration promotion penetrating,and slope instability sliding three *** the process of slope unstable evolution,rainfall and vibration play the roles of inducing and promoting slide *** addition,the deep cracks,which are the premise for the formation of the sliding surface,and the violent irregular fluctuation of soil pressure,which reflects the near penetration of the sliding surface,constitute the instability characteristics of the railway slope *** paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration,hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes.

关键词： Rainfall vibration joint action Small scale model tests Unstable evolution process Unstable characteristics Inducing sliding and promoting sliding

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Depositional and Bio-Sequence Stratigraphic Framework of Late Cretaceous Kawagarh Formation,Kala-Chitta Range,Pakistan:Equivalent of Gurpi Formation(Iran)

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Journal of earth Science 2024年第2期35卷 332-348页

作者： Muhammad Awais Bilal Wadood Muhammad Ishaq Muhammad Bilal Zeeshan Zafar Nasar Khan Aminullah Khan department of Geology University of SwabiAnbar-SwabiKhyber PakhtunkhwaSwabi23561Pakistan department of earth Environmental and Resources SciencesUniversity of Naples FedericoⅡNaples80126Italy State Key Laboratory of Continental dynamics Department of GeologyNorthwest UniversityXi’an710069China National Centre of Excellence in Geology University of PeshawarPeshawarKhyber Pakhtunkhwa25130Pakistan department of Geological Engineering School of Earth Sciences and EngineeringXi’an Shiyou UniversityXi’an610500China department of Petroleum Geology and Engineering School of Earth ResourcesChina University of GeosciencesWuhan430074China department of Geology University of MalakandDir Lower18800ChakdaraPakistan department of earth and Environmental Sciences KU LeuvenLeuven3001Belgium

The present study is focused on evaluation of deep marine pelagic sediments of Late Cretaceous Kawagarh Formation of Kala-Chitta Range in the context of microfacies analysis,paleoenvironmental interpretation,planktonic foraminiferal biostratigraphy,sequence stratigraphy and diversification of species.A total of thirty three rock samples were collected from the measured *** microfacies are interpreted,namely planktonic foraminifera wackestone,planktonic foraminifera mudstone and sandy mudstone indicating low energy depositional environment i.e.,outer *** biostratigraphic studies show plentiful planktonic foraminifera species of Globotruncana,Heterohelix and ***,no association of benthic or siliceous organisms was *** the basis of available species assemblage,a single local planktonic foraminifera biozone i.e.,Globotruncana-Heterohelix-Globotruncanita Assemblage Biozone is *** biozone information is combined with published literature and Lower Santonian to Middle Maastrichtian age has been assigned to the Kawagarh *** trend of species occurrences evinces that species number decreases over time with pulsated rise in the Kawagarh *** Kawagarh Formation carbonates show an overall Transgressive Systems Tract(TST).The Kawagarh Formation of Pakistan evinces analogous characteristics to that of the Late Cretaceous Gurpi Formation of Iran based on the geologic age,outcrop lithology,microfacies,planktonic foraminiferal assemblages,depositional setting and sequence stratigraphy.

关键词： depositional fabric biostratigraphy sequence stratigraphy Late Cretaceous Kawagarh Formation Pakistan Gurpi Formation Iran

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Convex-up Style of Deformation within Grabens in Regions of Incomplete Crossing Conjugate Normal Faults: A Numerical Simulation Investigation and Case Study

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Journal of earth Science 2024年第3期35卷 839-849页

作者： Zheng Li Kai Wang Xiong Xiong Bing Zhou School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China State Key Laboratory of Geodesy and earth’s dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China department of earth Sicences Khalifa UniversityAbu DhabiUnited Arab Emirates

Crossing conjugate normal faults(CCNFs)are extensively developed in many hydrocarbon-producing basins,generally existing in the form of incomplete ***,the effect of the non-conjugate zone of the CCNFs on the conjugate relay zone post late tectonic action has not been previously *** use 3D elastic-plastic modeling to investigate the influence of incomplete(i.e.,partially intersecting)CCNFs on the pattern of deformation of strata in the intersection region.A series of model simulations were performed to examine the effects of horizontal tectonic extension,fault size,and fault depth on the deformation of conjugate relay zones of incomplete *** analyses yielded the following results.(1)The model of incomplete conjugation predicts a convex-up style of deformation in the conjugate graben region superimposed on overall subsidence under applied horizontal tectonic extension.(2)The degree of convex-up deformation of the conjugate graben depends on the influence of the non-conjugate zone on the conjugate relay zone,which varies with the amount of horizontal tectonic extension,fault size,and fault burial depth.(3)Our results indicate that incomplete CCNFs can form convex-up deformation,similar to that in the Nanpu Sag area and provide a sound understanding of hydrocarbon migration and accumulation.

关键词： incomplete conjugate normal fault conjugate graben convex-up deformation hydrocarbons Nanpu Sag tectonics.

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Rheology of continental lithosphere and seismic anisotropy

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Science China earth Sciences 2024年第1期67卷 31-60页

作者： Shengsi SUN Yunpeng DONG Yixi LI Yihai YANG Chao CHENG Bo HUI Bin ZHANG Rutao ZANG State Key Laboratory of Continental dynamics Department of GeologyNorthwest UniversityXi’an 710069China Shaanxi earthquake Agency Xi’an 710068China

Rheology of rocks controls the deformation of the earth at various space-time scales,which is crucial to understand the tectonic evolution of continental *** of rock rheology are mainly conducted via high-pressure and hightemperature rheological experiments and multi-scale observations and measurements of naturally deformed *** present,a large amount of data from such kinds of studies have been *** paper first provides an up-to-date comprehensive review of the rheological mechanisms,fabric types and seismic properties of the main rock-forming minerals at different depths of continental lithosphere,including olivine,orthopyroxene,clinopyroxene,amphibole,plagioclase,quartz and ***,progress in high-pressure and high-temperature experiments and natural deformation observations is introduced,mainly regarding the rheological strength and behavior,seismic velocity and anisotropy of lithospheric mantle peridotite,eclogite,mafic granulite,amphibolite and felsic ***,by taking the Tibetan Plateau as an example,the application of rock rheology for quantitative interpretation of seismic anisotropy data is *** combination of mineral deformation fabrics and seismic anisotropy is expected to make an important breakthrough in understanding the rheological properties and structure of continental lithosphere.

关键词： Lithosphere Mineral fabric Rheology Seismic velocity Anisotropy

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Increased glacier melt enhances future extreme floods in the southern Tibetan Plateau

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Advances in Climate Change Research 2024年第3期15卷 431-441页

作者： He SUN Tan-Dong YAO Feng-Ge SU Tinghai Ou Zhihua HE Guoqiang TANG Deliang CHEN State Key Laboratory of Tibetan Plateau earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden Centre for Hydrology University of SaskatchewanSaskatoon S7N 1K2Canada Climate and Global dynamics National Center for Atmospheric ResearchBoulder CO 80307USA

Mountainous areas are of special hydrological concern because topography and atmospheric conditions can result in large and sudden floods,posing serious risks to water-related safety in neighbouring *** Yarlung Zangbo(YZ)River basin is the largest river basin on the Tibetan Plateau(TP),but how floods will discharge in this basin and how the role of glacier melt in floods will change throughout the 21st-century under shared socioeconomic pathways scenarios(SSP2-4.5 and SSP5-8.5)remain ***,we comprehensively address this scientific question based on a well-validated large-scale glacier-hydrology *** results indicate that extreme floods was projected to increase in the YZ basin,and was mainly reflected in increased duration(4–10 d per decade)and intensity(153–985 m^(3)s^(−1)per decade).Glacier runoff was projected to increase(2–30 mm per decade)throughout the 21st-century,but there was also a noticeable decrease or deceleration in glacier runoff growth in the late first half of the century under the SSP2-4.5,and in the latter half of the century under the *** melt was projected to enhance the duration(12%–23%)and intensity(15%–21%)of extreme floods under both SSPs,which would aggravate the impact of future floods on the socioeconomics of the YZ *** effect was gradually overwhelmed by precipitation-induced floods from glacier areas to YZ *** study takes the YZ basin as a projection framework example to help enrich the understanding of future flood hazards in basins affected by rainfall-or meltwater across the TP,and to help policy-makers and water managers develop future plans.

关键词： floods glacier Tibetan

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Exploring the combination of biochar‐amended soil and automated irrigation technology for water regulation and preservation in green infrastructure

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Deep Underground Science and Engineering 2024年第1期3卷 39-52页

作者： Honghu Zhu Yuanxu Huang Haihong Song Jian Chen Songlei Han Tanwee Mazumder Ankit Garg School of earth Sciences and Engineering Nanjing UniversityNanjingChina department of Civil and Smart Engineering Construction Guangdong Engineering Center for Structure Safety and Health MonitoringShantou UniversityShantouChina Shanghai Municipal Engineering Design Co. LtdShanghaiChina Indian Institute of Technology Madras ChennaiIndia

Biochar is a carbon sink material with the potential to improve water retention in various ***,for the long‐term maintenance of green infrastructure,there is an additional need to regulate the water contents in the covers to maintain vegetation growth in semiarid *** this study,biochar‐amended soil was combined with subsurface drip irrigation,and the water preservation characteristics of this treatment were investigated through a series of one‐dimensional soil column *** ascertain the best treatment method specific to semiarid climatic conditions,the test soil was amended with 0%,1%,3%,and 5%*** irrigation devices equipped with soil moisture sensors were used to control the subsurface water content with the aim of enhancing vegetation *** soil column test lasted 150 h,during which the volumetric water contents and soil suction data were *** experimental results reveal that the soil specimen amended with 3%biochar is the most water‐saving regardless of the time *** with a higher biochar content(e.g.,5%)consumes a more significant amount of water due to the enhancement of the water‐holding *** on the experimental results,it can be concluded that the appropriate ratio can be determined within 1%–3%,which can reduce not only the amount of irrigated/used water but also the time *** technology can be explored for water content regulation in green infrastructure and the development of barriers for protecting the environment around deep underground waste containment.

关键词： biochar drip irrigation underground water preservation water regulation

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Structural Geology and Chronology of Shear Zones along the Shangdan Suture in Qinling Orogenic Belt,China:Implications for Late Mesozoic Intra-Continental Deformation of East Asia

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Journal of earth Science 2024年第2期35卷 376-393页

作者： Falak Sheir Wei Li Le Zhang Basil Alabowsh Liuqing Jiang Li Liang Sainan Gao Shair Baz Umar Ashraf State Key Laboratory of Continental dynamics Department of GeologyNorthwest UniversityXi’an710069China Institute of Geology University of PunjabLahore45590Pakistan

The Shangdan suture zone(SDZ)in the Qinling orogenic belt(QOB)is a key to understanding the East Asia tectonic *** SDZ gives information about convergent processes between the North China Block(NCB)and South China Block(SCB).In the Late Mesozoic,several shear zones evolved along the SDZ boundary that helps us comprehend the collisional deformation between the NCB and SCB,which was neglected in previous *** shear zones play an essential role in the tectonic evolution of the East Asia *** study focuses on the deformation and geochronology of two shear zones distributed along the SDZ,identified in the Shaliangzi and Maanqiao *** shear sense indicators and kinematic vorticity numbers(0.54–0.90)suggest these shear zones have sinistral shear and sub-simple shear deformation *** quartz’s dynamic recrystallization and c-axis fabric analysis in the Maanqiao shear zone(MSZ)revealed that the MSZ experienced deformation under green-schist facies conditions at∼400–500℃.The Shaliangzi shear zone deformed under amphibolite facies at∼500–700℃.The^(40)Ar/^(39)Ar(muscovite-biotite)dating of samples provided a plateau age of 121–123 *** with previously published data,our results concluded that QOB was dominated by compressional tectonics during the Late Early ***,we suggested that the Siberian Block moved back to the south and Lhasa-Qiantang-Indochina Block to the north,which promoted intra-continental compressional tectonics.

关键词： Qinling orogenic belt Shangdan suture zone shear zone Late Mesozoic intra-continental deformation East Asia tectonics

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Efficient Spin-Flip between Charge-Transfer States for High-Performance Electroluminescence, without an Intermediate Locally Excited State

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Research 2024年第1期2023卷 339-349页

作者： Donghai Zhang Shanshan Jiang Xiaodong Tao Fulin Lin Lingyi Meng Xu-Lin Chen Can-Zhong Lu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China FuzhouFujian 350108China Xiamen Key Laboratory of Rare earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamenFujian 361021China University of Chinese Academy of Sciences Beijing 100049China

Thermally activated delayed fluorescence(TADF)materials with both high photoluminescence quantum yield(PLQY)and fast reverse intersystem crossing(RISC)are strongly desired to realize efficient and stable organic light-emitting diodes(OLEDs).Control of excited-state dynamics via molecular design plays a central role in optimizing the PLQY and RISC rate of TADF materials but remains ***,3 TADF emitters possessing similar molecular structures,similar high PLQYs(89.5%to 96.3%),and approximate energy levels of the lowest excited singlet states(S_(1)),but significantly different spin-flipping RISC rates(0.03×10^(6) s^(−1) vs.2.26×10^(6) s^(−1))and exciton lifetime(297.1 to 332.8μs vs.6.0μs)were systematically synthesized to deeply investigate the feasibility of spin-flip between charge-transfer excited states(^(3)CT–^(1)CT)transition.

关键词： transition lifetime desired

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Astrometric Observations of NEA 1998 HH49 Using the Daocheng 50 cm Telescope

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Research in Astronomy and Astrophysics 2024年第7期24卷 74-81页

作者： Huan Xu Xiang-Ming Cheng Yi-Gong Zhang Teng-Fei Song Zhen-Jun Zhang Qing-Yu Peng Yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of the structure and Evolution of Celestial Objects Chinese Academy of Sciences Engineering Laboratory on Applied Astronomical Technology of Yunnan School of Information Engineering Kunming University School of Computer Science and Information Engineering Anyang Institute of Technology department of Computer Science Jinan University Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan University

This study details an astrometric observation campaign of the Near-earth Asteroid 1998 HH49, conducted with the aim of refining our understanding of its physical characteristics. Utilizing the 50 cm telescope located at the Wumingshan Mountain in Daocheng, Sichuan, images were obtained over four nights, from 2023 October 19 to October 22. These observations were processed using Astrometrica software, facilitating the precise determination of the asteroid's position. The observational results were compared with the ephemerides from three distinct sources to verify accuracy: the Jet Propulsion Laboratory(JPL) Horizons System, the Institut de Mécanique Céleste et de Calcul des éphémérides(IMCCE) Miriade, and the Near-earth Objects Dynamic Site(NEODyS-2).When compared with the JPL ephemeris, a mean observed-minus-calculated(O-C) result of 0.''07 in the *** and-0.''35 in the decl. direction was yielded. Furthermore, the comparison with the IMCCE ephemeris yielded mean O-C results of 0.''08 in the R.A. direction and-0.''06 in the decl. direction. The comparison with the NEODyS-2 ephemeris yielded the mean O-C results of 0.''06 in R.A. and-0.''49 in decl. direction. The study's findings demonstrate a general consistency between the observed data and the ephemeris predictions, with minor discrepancies observed across the data sets. Notably, both the JPL and NEODyS-2 ephemerides show that the residuals in the decl. direction exceed those in the R.A. direction. The disparities may result from atmospheric differential color refraction, ephemeris discrepancies, observational errors, and other factors. Additionally, it is worth noting that further investigation is required due to the potential influence of additional factors. Overall, the Daocheng 50 cm Telescope exhibits the ability to conduct high-precision positional measurements.

关键词： astrometry ephemerides time

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