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Acta Geologica Sinica(English Edition) 2024年第1期98卷 67-82页

作者： Nadezhda KANYGINA Andrey TRETYAKOV Dmitriy ALEXEIEV Kirill DEGTYAREV Anfisa SKOBLENKO Natalia SOLOSHENKO Boris ERMOLAEV geological institute Russian Academy of SciencesMoscow 119017Russia A.N.Zavaritsky institute of Geology and Geochemistry Ural Branch of the Russian Academy of SciencesYekaterinburg 620016Russia

The combined petrographic,petrological,geochemical and geochronological study of the Neoproterozoic gneisses of the Sarychabyn and Baskan complexes of the Junggar Alataw of South Kazakhstan elucidate the Precambrian tectonic evolution of the Aktau–Yili *** is one of the largest Precambrian crustal blocks in the western Central Asian orogenic *** U-Pb single-grain zircon ages indicate that granite-gneisses formed from the same source and crystallised in the early Neoproterozoic ca.930–920 *** chemical composition of gneisses corresponds to A2-type *** whole-rock Nd isotopic characteristics(εNd(t)=−4.9 to−1.0 and TNd(DM-2st)=1.9 to 1.7 Ga)indicate the involvement of Paleoproterozoic crustal rocks in magma *** Neoproterozoic ca.930–920 Ma A-type granitoids in the Aktau–Yili terrane of South and Central Kazakhstan might reflect within-plate magmatism adjacent to the collisional belt or a local extension setting in back-arc areas of the continental arc.

关键词： granitoid magmatism geochemistry geochronology Sm-Nd isotope systematics Neoproterozoic Junggar Alataw Kazakhstan Central Asian orogenic belt

U-Pb dating of bastnäsite from the Vuoriyarvi massif:An example application for assessing the REE potential of carbonatite-related deposits

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Geoscience Frontiers 2024年第5期15卷 444-453页

作者： Evgeniy N.Kozlov Ekaterina N.Fomina Qiuli Li Jiao Li geological institute Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline *** carbonatites of the Vuoriyarvi massif contain abundant rare-earth mineralization mainly represented by ancylite-(Ce)and bastnäsite-(Ce).Ancylite was previously shown to have probably formed in the Devonian(ca.365 Ma)during an early postmagmatic *** geological observations have revealed a much later crystallization of bastnäsite but have not been able to specify the exact age of the *** in situ U-Pb dating of bastnäsite allowed us to constrain its ***äsite for this study was extracted from two varieties of dolomite carbonatite breccias cemented by(1)quartz-bastnäsite and(2)strontianite aggregates(hereafter bastnäsite-rich and strontianite-rich carbonatites–BRC and SRC,respectively).The obtained age estimations(237.7±9.8 Ma and 239.9±4.1 Ma,respectively)indicate that both studied rocks were formed during a single *** revealed age difference(~125 Ma)excludes the genetic link between the bastnäsite origin and regional alkaline magmatism,pointing out an additional source for the Vuoriyarvi bastnäsite-bearing ***,the obtained U-Pb ages provide strong evidence that a Triassic event is responsible for the occurrence of bastnäsite mineralization due to hydrothermal REE redistribution from the Devonian ancylite-rich *** of the REEs released during this process via dissolution of ancylite were precipitated in situ as bastnäsite,while strontium was transported and incorporated into *** Pb isotopic characteristics of bastnäsite(^(206)Pb/^(204)Pb=18.1±0.1,^(207)Pb/^(204)Pb=15.3±0.1,and^(207)Pb/^(206)Pb=0.84±0.01)are most probably inherited from the Devonian host rocks of the Vuoriyarvi massif involved in the Triassic *** signatures of Pb,Sr,and Nd show that the depleted mantle and lower crust played the leading role in formation of the Vuoriyarvi alkaline

关键词： Bastnäsite REE Carbonatites U-Pb dating Vuoriyarvi Kola alkaline province

Kuedinskie Kluchiki, a Unique Middle Permian Biota Locality as a Key-point for Reconstruction of Late Paleozoic Terrestrial Ecosystems of the Urals, Russia

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 850-866页

作者： Serge V.NAUGOLNYKH geological institute of russian academy of sciences Pyzhevsky per.7119017 MoscowRussia

Field work focused on the Kuedinskie Kluchiki locality, Perm region, Urals, Russia, which contains a rich assemblage of diverse fossil organisms including higher plants(equisetophytes, pteridosperms, ginkgophytes, conifers, vojnovskyans) represented by stems, leaves and reproductive organs;invertebrates(mollusks, arthropods), and tetrapods(temnospondyl amphibians, seymouriamorphs, cotylosaurs, synapsids, diapsids), as well as bony fishes. General characteristics of the taxonomical composition of the Kuedinskie Kluchiki locality are given. A new peltaspermalean pteridosperm taxon, Compsopteris longipinnata sp. nov., and a voltzialean conifer Archaeovoltzia kuedensis sp. nov. are described. General considerations on the paleoecologic and paleogeographic conditions of the Kuedinskie Kluchiki locality origin are given.

关键词： paleobotany paleoecology taxonomy Lagerst?tten new taxa peltasperms conifers Wordian Cis-Urals

Quaternary 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 1360-1394页

作者： Yong WANG Mianping ZHENG Yuan LING Shuyuan XIANG Zhaogang SHAO Kexin ZHANG Xue KE Xiao LIN Fang HAN Jian’en HAN institute of Geology Chinese Academy of Geological SciencesBeijing 100037China institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China Faculty of Earth sciences China University of GeosciencesWuhan 430074China Chinese academy of geological sciences Beijing 100037China institute of geological Survey China University of GeosciencesWuhan 430074China School of Earth sciences East China University of TechnologyNanchang 330013China institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

The Quaternary strata on the Qinghai-Tibet Plateau contain rich information about the paleoclimate and environmental evolution,record the evolution process of the Quaternary regional tectonics,paleogeography,and geomorphology of the plateau,and are extremely important areas for studying the Quaternary geological events and regional environmental *** to a comprehensive analysis of the regional stratigraphic data and the development and evolution characteristics of the biota,based on the differences in the lithostratigraphic units,sedimentary characteristics,landforms,and drainage systems,the Quaternary strata on the Qinghai-Tibet Plateau and its surrounding areas are divided into five stratigraphic regions:the Tarim region,Loess Plateau region,Qinghai-Tibet Plateau region,Yunnan-Guizhou Plateau region,and India-Ganges *** Qinghai-Tibet Plateau stratigraphic region is divided into seven stratigraphic sub-regions:the West Kunlun-Karakorum,AltunQilian Mountains,Qaidam-Hehuang,East Kunlun-Bayan Har,Qiangtang,East Xizang-West Yunnan-West Sichuan,and Gangdise-Himalayan *** paper briefly describes the lithostratigraphic units of the seven stratigraphic sub-regions of the Qinghai-Tibet *** to the lithostratigraphic sequence and its sedimentary characteristics,stratigraphic contact relationship,formation age,and evolution of the biota in each stratigraphic sub-region,the Quaternary tectonic paleogeographic evolution of the Qinghai-Tibet Plateau is divided into four stages.(1)The inherited differential uplift stage since the Pliocene(2.6-1.8/1.5 Ma):the regional sedimentary differences were significant,and the stratigraphic distribution was limited,the alluvial-proluvial sandy conglomerate was widely developed along the piedmont,and fluvial and lacustrine deposits were developed in the low-lying areas between the mountains.(2)The mountain range flattening stage(1.8/1.5-1.2/0.8 Ma):the erosion unconformity surfaces around the pl

关键词： Quaternary stratigraphic sedimentary

Thermo-and pH-sensitive Polymer with Pendant Spacer-linked Imidazole Cycles

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Chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： Natalya V.Zakharova Stanislav N.Zelinskiy Mariya S.Strelova Elena N.Danilovtseva Vadim V.Annenkov institute of Macromolecular Compounds of the russian academy of sciences Saint Petersburg199004Russia Limnological institute of Siberian Branch of the russian academy of sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring removed from the main chain by a spacer of five bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitive properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and viscometry. The observed ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more actively than poly(1-vinylimidazole), which is of interest for gene delivery applications. The polymer cross-linked with epichlorohydrin gives micro-relief coatings on the plastic surface, and the modified surface is able to attach negatively charged objects. This thermo-and pH-sensitive polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitivity The modified surface DNA immobilization

Constraints on crustal compositional architecture across the North China-Altaids transition and implications for craton margin reworking

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National Science Review 2024年第05期11卷 121-133页

作者： Zhuo Ye Xiaomiao Tan Rui Gao Qiusheng Li Hongshuang Zhang Xiaoyang Wu Wenhui Li Yingkang Li Sino Probe Center Chinese Academy of Geological Sciences Key Laboratory of Deep-Earth Dynamics Ministry of Natural Resources Institute of Geology Chinese Academy of Geological Sciences School of Earth sciences and Engineering Sun Yat-sen University Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of Sciences China geological Sample Information Center China Geological Survey

The phase of secular evolution of continents is manifested as the degree of compositional differentiation,modification and maturation of continental crusts, which is vital in understanding the mechanism of continental evolution but is difficult to quantify. Here we use integrated passive-and active-source seismic profiling to conduct joint analysis and inversion and derive Vs and Vp/Vs section models across the North China Craton(NCC) to southeastern Altaids boundary zone that bears a tectonic transition from a reworked ancient craton margin to a Phanerozoic accretionary orogen. We systematically exploited the imaged multiple physical properties as precise and delicate proxies to constrain the compositional architecture in the crust across this important tectonic transition subject to various crustal evolutional phases. Our Vs and Vp/Vs imaging, together with the existing isotopic data, characterizes the Yin Shan–Yan Shan belt as the northern NCC margin with layered homogeneous compositions that point to an evolved crust. However, the lower-crustal low-Vs/high-Vp/Vs signature that overlaps the shallowly dipping to horizontal reflective fabrics suggests that the crust of the northern NCC margin has undergone considerable reworking through lower-crustal-stretching-assisted melt migration and mixing since the late Paleozoic to Mesozoic eras. The process probably involved crust–mantle interaction and thus resulted in a compositionally modified ancient crustal basement. On the contrary, the southeastern Altaids domain manifests crustal complexity in compositions and structures inferred to be indicative of a juvenile crust of the Phanerozoic accretionary orogen. Our results provide deep physical-property constraints that shed new light on the crustal evolution of a complex craton margin.

关键词： North China Craton Altaids crustal composition receiver function joint inversion continental reworking

Phanerozoic Tectonic Evolution,Metallogenesis and Formation of Mineral Systems in China

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 819-842页

作者： CHEN Xuanhua HAN Lele DING Weicui XU Shenglin TONG Ying ZHANG Yiping LI Bing ZHOU Qi WANG Ye SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100037China institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

The continental Asia is mainly composed of three major tectonic regimes,the Tethys,Paleo Asian Ocean,and West *** underwent multi-stage plate convergences,ocean-continent transformations,and subductions,collisions and/or collages,and post collisional(orogenic)extensions in *** evolution of the Asia brings up a unique fault system and tectonic geomorphological features in the China's ***,it provides a geodynamic background for the formation and evolution of metallogeneses and mineral systems,resulting in nonuniform distribution of tectono-metallogenic systems and metallogenic *** spatiotemporal distribution of mineral deposits in China and adjacent areas exhibits periodic variation under controlling of the full life Wilson cycle and tectonic evolution,forming the plate convergence-related mineral system in East *** Cu deposits are mainly related to compressional systems in Paleozoic and early Mesozoic,and more closely related to post-collision extensional settings in late Mesozoic and *** Au deposits mainly formed in post-orogeny extensional *** rock related rare earth element deposits formed mainly at margins of the North China and Yangtze ***-pegmatite Li and other rare metal deposits formed mainly in early Mesozoic,related to Indosinian post-orogeny ***-metallogenic systems provide important basis for the prospecting of mineral resources.

关键词： tectonic evolution geodynamic system post-orogenic extension metallogenesis tectono-metallogenic system East Asia

Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.KOZLOV Ekaterina V.LEBEDEVA institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia institute of Geography Russian Academy of SciencesMoscow 119017Russia

Volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric *** has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal *** lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric *** was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their *** volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were *** observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 *** analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their *** results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： Volcanic lakes Echolocation survey Volcanism Gashydrotherms Kamchatka Kuril Islands

New grating compressor designs for XCELS and SEL-100 PW projects

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High Power Laser Science and Engineering 2024年第3期12卷 126-133页

作者： Efim Khazanov Gaponov-Grekhov institute of Applied Physics of the russian academy of sciences Niznij NovgorodRussia

The problem of optimizing the parameters of a laser pulse compressor consisting of four identical diffraction gratings is solved *** goal of optimization is to obtain maximum pulse power,completely excluding both beam clipping on gratings and the appearance of spurious diffraction *** analysis is carried out in a general form for an out-of-plane *** particular‘plane'cases attractive from a practical point of view are analyzed in more detail:a standard Treacy compressor(TC)and a compressor with an angle of incidence equal to the Littrow angle(LC).It is shown that in both cases the LC is superior to the ***,for 160-cm diffraction gratings,optimal LC design enables 107 PW for XCELS and 111 PW for SEL-100 PW,while optimal TC design enables 86 PW for both projects.

关键词： Littrow angle compressor multi-petawatt lasers Treacy compressor

Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

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Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina R.Gasilova Daria N.Poshina Aleksandra O.Sitnikova Natalia N.Saprykina Yury A.Skorik institute of Macromolecular Compounds of the russian academy of sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—OSO3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcOH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcOH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering