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The effects of local variations in conditions on carbon storage and release in the continental mantle

National Science Review 2024年第6期11卷 22-36页

作者： Stephen F.Foley Chunfei Chen Dorrit E.Jacob School of Natural sciences Macquarie University research School of earth sciences Australian National University State Key laboratory of Geological Processes and Mineral resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. Future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

关键词： lithospheric mantle carbonate melts deep carbon cycle craton destruction continental rifts

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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang Li Yu Liu Xiao-Xiao Ling Li-Guang Wu Li Yang Lan Yang Bo Yang Yong-Gang Zhao Xian-Hua Li State Key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University mining research Institute Baotou Iron and Steel(Group) Co.LTD State Key laboratory of Baiyunobo Rare earth Resource research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

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Insights of carbon reduction practices from Winter Olympics 2022

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Science Bulletin 2024年第13期69卷 2034-2037页

作者： Xiaoyong Liao Shuai Zhong Jie Huang Zhu Liu Ayman Elshkaki You Li Lei Shen Yingli He Li An Yidong Zhu Wenhao Sun Tao Liang Jiaoe Wang Jinwei Dong Key laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key laboratory for resources Use and Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China Department of earth System Science Tsinghua UniversityBeijing 100084China

Concerns about the carbon emissions of mega-events revolve,mainly due to the impactful demonstration effects they ***,accurate monitoring of these emissions is crucial during such events[1].The Olympic and Paralympic Winter Games Beijing 2022(hereinafter“Winter Olympics 2022”)are recognized as the first Games to pay close attention to a wide range of emissions associated with all stages of the *** of emerging carbon reduction technologies,such as low-carbon materials and technologies,have shown promising effects on efforts to achieve carbon neutrality[2].The impacts of individual measures,such as Olympic infrastructure construction.

关键词： Winter emissions carbon

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Permian integrative stratigraphy,biotas,paleogeographical and paleoclimatic 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 1107-1151页

作者： Shuzhong SHEN Yichun ZHANG Dongxun YUAN Haipeng XU Qi JU Hua ZHANG Quanfeng ZHENG Mao LUO Zhangshuai HOU State Key laboratory for Mineral Deposits research School of Earth Sciences and Engineering and Frontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China State Key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of sciences Nanjing 210049China School of resources and Geosciences China University of Mining and TechnologyXuzhou 221116China

The Permian Period was a critical time interval during which various blocks of the Qinghai-Tibetan Plateau have experienced profound and complex paleogeographical *** supercontinent Pangea was formed to its maximum during this interval,hampering a global east-to-west trending equatorial warm ocean ***,a semi-closed Tethys Ocean warm pool formed an eastward-opening oceanic embayment of Pangea,and became an engine fostering the evolutions of organisms and environmental changes during the Paleozoic-Mesozoic *** and preserved fossil groups have proved extremely useful in understanding such changes and the evolutionary histories of the Qinghai-Tibetan *** distributed Permian deposits and fossils from various blocks of the Qinghai-Tibetan Plateau exhibited varied characteristics,reflecting these blocks’different paleolatitude settings and drifting *** Himalaya Tethys Zone south to the Yarlung Zangbo suture zone,located in the northern Gondwanan margin,yields fossil assemblages characterized by cold-water organisms throughout the Permian,and was affliated to those of the *** of the exotic limestone blocks within the Yarlung Zangbo suture zone are Guadalupian(Middle Permian)to Early Triassic in *** exotic limestone blocks bear fossil assemblages that have transitional affinities between the warm Tethys and cold Gondwanan regions,suggesting that they most probably represent seamount deposits in the Neo-Tethys *** the Asselian to Sakmarian(Cisuralian,also Early Permian),the Cimmerian microcontinents in the northern part of Gondwana preserved glacio-marine deposits of Asselian to Sakmarian,and contained typical Gondwana-type cold-water *** the middle Cisuralian(~290-280 Ma),the Cimmerian microcontinents rifted off from the Gondwanaland,and drifted northward allometrically due to the active magmatism of the Panjal Traps in the northern margin of the Indian *** slices of micro

关键词： Permian Tethys Ocean Qinghai-Tibetan Plateau Biotas Paleogeography

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Matrix Assisted Laser Desorption Ionization Time of Flight(MALDI-TOF)-Mass Spectrometry and^(13)C-NMR-Identified New Compounds in Paraberlinia bifoliolata(Ekop-Beli)Bark Tannins

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Journal of Renewable Materials 2024年第3期12卷 553-568页

作者： Liliane Nga Benoit Ndiwe Achille Bernard Biwolé Antonio Pizzi Jean Jalin Eyinga Biwole Joseph Zobo Mfomo laboratory of Forest resources and Wood Valorization Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 1872DoualaCameroun laboratory of Mechanics Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 2701DoualaCameroun laboratory of Studies and research on Wood Material(LERMAB) University of LorraineNancyFrance

Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial *** discovery of new tannins is therefore *** aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica *** by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of *** are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic *** identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion *** information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the *** analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.

关键词： Tannin Paraberlinia bifoliolata Central African wood species MALDI-TOF/MS 13C NMR bark extracts thermomechanical behaviour wood-binder

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DynIceData:a gridded ice-water classification dataset at short-time intervals based on observations from multiple satellites over the marginal ice zone

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Big earth Data 2024年第2期8卷 249-273页

作者： Lin Huang Yubao Qiu Yang Li Shuwen Yu Wanyang Zhong Changyong Dou Key laboratory of Digital earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina International research Center of Big Data for Sustainable Development Goals BeijingChina University of Chinese Academy of sciences BeijingChina School of resources and Geosciences China University of Mining and TechnologyXuzhouChina

High-resolution observations of short-term changes in sea ice are critical to understanding ice dynamics and also provide important information used in advice to shipping,especially in the *** individual satellite sensors provide periodic sea ice obser-vations with spatial resolutions of tens of meters,information regarding changes that occur over short time intervals of minutes or hours is *** this study,a gridded ice-water classification dataset with a high temporal resolution was developed based on observations acquired by multiple satellite sensors in the Marginal Ice Zone(MIZ).This dataset-DynIceData-which combines Sentinel-1 Synthetic Aperture Radar(SAR)data with Gaofen-3(GF-3)SAR and SDGSAT-1 thermal infrared imagery was used to obtain observations of the MIZ with a range of temporal resolutions ran-ging from minutes to tens of *** areas of the Arctic covered include the Kara Sea,Beaufort Sea,and Greenland Sea during the period from August 2021 to August ***-oriented segmen-tation and thresholding were used to obtain the ice-water classifi-cation map from Sentinel-1 and GF-3 SAR image pairs and Sentinel-1 SAR and SDGSAT-1 thermal image *** time interval between the images in each pair ranged from 1 minute to 68 ***-kilometer grid sample granules with a spatial resolution of 25 m for the GF-3 SAR data and 30 m for the SDGSAT-1 thermal data were *** classification was verified as having an overall accuracy of at least 95.58%.The DynIceData dataset consists of 7338 samples,which could be used as reference data for further research on rapid changes in sea ice patterns at different short time scales and provide support for research on thermodynamic and dynamic models of sea ice in combination with other environmen-tal data,thus potentially improving the accuracy of sea ice forecast-ing using Artificial *** dataset can be accessed at https://***/10.57760/sciencedb.j00001.00784.

关键词： Sea ice dynamics ice-water classification GF-3 SDGSAT-1 marginal ice zone

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Occurrence of microplastics in natural and farmland soil in the Qilian Mountains of the Northern Tibetan Plateau

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Journal of Mountain Science 2024年第7期21卷 2159-2172页

作者： KANG Qiangqiang ZHANG Yulan KANG Shichang ZHANG Shengyin LUO Xi LI Longrui WANG Zhaoqing ZHANG Shuncun Key laboratory of Petroleum resources Exploration and Evaluation Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of sciences Beijing 100049China Key laboratory of Cryospheric Science and Frozen soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of earth and Environmental sciences Lanzhou UniversityLanzhou 730000China

Microplastics(MPs)become ubiquitous in soil and are an environmental and public health concern ***,the status of MPs in natural and farmland soils in remote areas remains poorly *** this study,we investigated the characteristics of MPs in natural and farmland soils along two transects in the Qilian Mountains of the northern Tibetan *** average abundance of MPs in natural and farmland soils was 29,778 and 56,123 items kg^(-1),respectively,with a detection size range of 10-1000μ*** in the size range of 10-100μm accounted for 84.1%of particles *** the 21 polymers detected,polyethylene dominated in both farmland and natural *** shape of MPs was dominated by fragments(95.8%),followed by fibers(3.8%)and beads(0.4%).The abundance of MPs was positively correlated with increasing altitude in natural *** was no significant correlation between the abundance of MPs and soil physicochemical properties due to the narrow range of values of soil physicochemical *** the growing concern regarding MPs pollution,research on the status of MPs in high altitude and remote areas is critical to understanding their global cycle.

关键词： Microplastics pollution soil Remote areas Tibetan Plateau

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Integrated hazard assessment of rockfall incidents in the Cap Aokas Cliff Region

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Journal of Mountain Science 2024年第6期21卷 1916-1929页

作者： Zohra LADJEL Farid ZAHRI Riheb HADJI Younes HAMED Karim ZIGHMI Kaddour BENMARCE Department of earth sciences Institute of Architecture and Earth SciencesFerhat Abbas UniversitySetif 19137Algeria unit of Emerging Materials research Ferhat Abbes UniversitySétif 19137Algeria laboratory of Applied research in Engineering Geology GeotechnicsWater Sciencesand EnvironmentFerhat Abbas UniversitySetif 19137Algeria International Association of Water resources in the Southern Mediterranean Basin Gafsa 2112Tunisia Department of earth sciences Faculty of SciencesUniversity of GafsaGafsa 2112Tunisia

Rock fall accidents in mountainous cliff areas have significant consequences for human life and *** study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast coast of Algeria by identifying the key factors contributing to rockfall *** employed a combination of kinematic analysis,Matterocking method,and 3D trajectory simulations to determine zones that are susceptible to rockfall *** using a probabilistic and structural approach in conjunction with photogrammetry,we identified the controlling *** kinematic analysis revealed the presence of five discontinuity families,which indicated both plane and wedge failure *** 3D trajectory simulations demonstrated that the falling blocks followed the stream *** then validated the susceptibility maps generated from the analysis using aerial photos and historical rockfall *** findings of this study enhance our understanding of rockfall phenomena and provide valuable insights for the development of effective strategies to mitigate rockfall hazards.

关键词： Trajectory simulations Probabilistic analysis Structural approach Rockfall hazard Cap Aokas cliff

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Divergent responses of runoff to climate change in the upper basins of the Third Pole dominated by westerlies and monsoon

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Science China earth sciences 2024年第8期67卷 2592-2614页

作者： Qikai SUN Fengge SU He SUN State Key laboratory of Tibetan Plateau earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100101China

The diverse climates,distribution of snow and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the Third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the westerlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in westerlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHT),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow(UYE),Lancang(ULC),Nujiang(UNJ),and Yarlung Zangbo(UYZ))of the Third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results showed that:(1)The annual runoff in the majority of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI showed a significant increasing trend from1961 to *** annual runoff in the upper basins of the Third Pole changed abruptly from decreasing to increasing between the 1980s and 2000s,with the exception of the UYE.(2)The runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the westerlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHT),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to warm season temperature changes in the most westerlies-dominated upper basins has decreased,while the response of runoff to precipitation changes has intensified.(3)The stud

关键词： Upper basins of the Third Pole Climate change Westerlies and monsoon Runoff variations Large-scale circulation factors

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Impacts of land surface darkening on frozen ground and ecosystems over the Tibetan Plateau

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Science China earth sciences 2024年第10期67卷 3213-3225页

作者： Shuchang TANG Tao WANG Dan LIU Tandong YAO Shilong PIAO Sino-French Institute for earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100101China State Key laboratory of Tibetan Plateau earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Tibetan Plateau(TP) is known as the “Third Pole” of the earth. Any changes in land surface processes on the TP can have an unneglectable impact on regional and global climate. With the warming and wetting climate, the land surface of the TP saw a darkening trend featured by decreasing surface albedo over the past decades, primarily due to the melting of glaciers, snow,and greening vegetation. Recent studies have investigated the effects of the TP land surface darkening on the field of climate, but these assessments only address one aspect of the feedback loop. How do these darkening-induced climate changes affect the frozen ground and ecosystems on the TP? In this study, we investigated the impact of TP land surface darkening on regional frozen ground and ecosystems using the state-of-the-art land surface model ORCHIDEE-MICT. Our model results show that darkening-induced climate changes on the TP will lead to a reduction in the area of regional frozen ground by 1.1×10~4±0.019×10~4km~2, a deepening of the regional permafrost active layer by 0.06±0.0004 m, and a decrease in the maximum freezing depth of regional seasonal frozen ground by 0.06±0.0016 m compared to the scenario without TP land surface ***, the darkening-induced climate change on the TP will result in an increase in the regional leaf area index and an enhancement in the regional gross primary productivity, ultimately leading to an increase in regional terrestrial carbon stock by0.81±0.001 PgC. This study addresses the remaining piece of the puzzle in the feedback loop of TP land surface darkening, and improves our understanding of interactions across multiple spheres on the TP. The exacerbated regional permafrost degradation and increasing regional terrestrial carbon stock induced by TP land surface darkening should be considered in the development of national ecological security barrier.

关键词： Tibetan Plateau Albedo Land surface darkening Frozen ground Ecosystem

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