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Evaluating the thermal environment of urban land surfaces in Yakutsk,a city located in a region of continuous permafrost

中国科学院地质与地球物理研究所2003学术年会

作者： DAI Yongding.ZHU Jingquan,li xiang and sheng jiying institute of geology and geophysics.chinese academy of sciences,P.O.Box 9825,Beijing 100029,China

Six genera of iron bacteria and six genera of blue bacteria have been discovered in Xuanlong iron *** hematitized bacteria and hematite foliates comprised bacteria pelletal,silky,fibrous and clasty pelletal lamina,in turn,which made up oncolite,stromatolite and *** the cooperation of the iron and blue bacteria,a great deal of divalent iron brought into Xuanlong Gulf by upwelling ocean current were oxygenized,precipitated,concentrated and ore-formed at last.

关键词： iron and blue bacteria bacterial laminae microbolite upwelling current

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Advances in Climate Change Research 2024年第1期15卷 113-123页

作者： xiang-Long li Ze ZHANG Jin-Xin LU Anatoli BROUCHKOV Qing-Kai YAN Qi-Hao YU sheng-Rong ZHANG Andrey MELNIKOV School of Civil Engineering and Transportation Institute of Cold Regions Science and EngineeringPermafrost InstituteNortheast Forestry UniversityHarbin150040China China Railway Qinghai-Tibet Group Company Xining 810000China Department of Geocryology Faculty of GeologyLomonosov Moscow State UniversityMoscow 119234Russian Federation State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco Envi ronment and Re sourcesChinese Academy of SciencesLanzhou 730000China Melnikov Permafrost institute Siberian BranchRussian Academy of ScienceYakutsk 677010Russian Federation

Rapid urbanization has led to changes in the urban land surface thermal ***,there are still much unknown about the urban land surface thermal conditions in permafrost *** is a unique geological environment,changes in the urban land surface thermal environment may trigger geological disasters caused by permafrost *** study utilized remote sensing data and geographic de-tectors to identify the dynamic changes in land surface temperature(LST)and land use/land cover(LU/LC)in Yakutsk,as well as the potential factors contributing to LST *** 1992 and 2020,the built-up area in Yakutsk increased by 36%,and the annual average LST in Yakutsk has risen by 6.67℃,accompanied by an expansion of high-temperature *** ongoing greening efforts,rapid urbanization poses a threat to these green *** in the normalized difference built-up index(NDBI)and land use transfer(LDT)were identified as the primary drivers of urban LST *** integrating geographic detector technology and artificial neural network models,we optimized the selection of input factors in the prediction model and used it to explore the future changes in LST in *** average LST in Yakutsk is expected to reach 23.4℃ and 25.1℃ in 2030 and 2040,respectively,with a further increase in high-temperature *** study provides a reference for ecological,hydrological,and geological assessments of cities in permafrost regions.

关键词： Remote sensing Land surface temperature Land use/Land cover Permafrost Yakutsk

RECONSIDERATION OF THE PHYLOGENETIC AFFINITIES OF ZHIJINITIDS

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微体古生物学报 2000年第3期 313-316页

作者： Qian Yi Zhu Mao yan li Guo xiang (Nanjing institute of geology and Palaeontology, chinese academy of sciences, Nanjing 210008) Chen Meng’e (institute of geology, chinese academy of sciences, Beijing 100029)

This discovery of complete body fossils of Halkieria and Microdictyon, two problematical taxa originally erected on the basis of isolated sclerites from Cambrian konservt lagersttte, sheds new light on our understanding of the Early Cambrian small shelly fauna. Based on comparisions of the morphology and preservation of nail shaped sclerites of zhijinitids, Hallucigenia and Onychodictyon, we propose that Zhijinites and Parazhijinites may have been closely related to tardipolypods, a diverse group of Early Cambrian metazoans.

关键词： small shelly fossils scleritome zhijinitids tardipolypods Early Cambrian

Ordovician 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 971-1004页

作者： xiang FANG Yong Yi ZHEN Guangxu WANG Xin WEI Zhongyang CHEN Yan liANG Xuejin WU Wenjie li Chao li Renbin ZHAN Yuandong ZHANG State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Geological Survey of New South Wales W.B.Clarke Geoscience CentreNSW 2753Australia University of chinese academy of sciences Beijing 100049China

The Ordovician rocks on the Qinghai-Tibetan Plateau represent the oldest non-metamorphic strata,and are critical to understanding the history of regional geology and biotic evolution of the entire *** of Floian,Darriwilian,Sandbian,Katian and Hirnantian are represented in the plateau with a hiatus of variable duration occurring underneath the basal Ordovician across the *** stratigraphical regions,including the Himalaya,Gangdise-Zayu,Qiangtang-Qamdo,Songpan-Garze,and Karakoram-Kunlun-Altun,are differentiated for the Ordovician strata,which are correlated with their equivalents in the Sibumasu,Indochina,Qaidam-Qilian,Tarim-Tianshan,and the Yangtze(western margin)stratigraphical *** the QinghaiTibetan Plateau,graptolites,conodonts,and cephalopods are the most common and useful fossils for the Ordovician *** Ordovician biotas of the Qinghai-Tibetan Plateau bear some distinguishable palaeobiogeographical signatures,among which the cephalopods are characterized by the flourishing actinocerids of North China affinity in the Early-Middle Ordovician,and by the thriving lituitids and orthocerids of South China affinity in the Middle-Late *** occurrences and their palaeobiogeographical evolution provide critical evidence bearing on the reconstruction of the geological history of the Qinghai-Tibetan Plateau and surrounding terranes in northeastern *** stratigraphical successions of the Cambrian-Ordovician transition in the Himalaya and Lhasa and nearby Sibumasu terranes were significantly affected by the Kurgiakh Orogeny,which resulted in the extensive unconformity between the Ordovician and the underlying rocks in most areas of the Qinghai-Tibetan *** southern Xizang,a warm-water biota of Middle Ordovician age was recovered from oolitic limestones,suggesting a likely palaeogeographical location in low-latitudes near the *** the Himalaya and Sibumasu regions,the Upper Ordovician was typified by t

关键词： Ordovician Chronostratigraphy lithostratigraphy Biostratigraphy Palaeobiogeography Qinghai-Tibetan Plateau

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GEOCHEMISTRY AND MICROFABRIC OF OOliTIC IRONSTONE IN THE XUANLONG AREA OF HEBEI PROVINCE, NORTHERN CHINA

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Scientia Geologica Sinica 2000年第1期 61-70页

作者： li xiang (institute of geology and geophysics, chinese academy of sciences, Beijing 100029) Dong Yushan (China University of Geosciences, Beijing 100083)

Xuanlong-type iron Formation distributes in Xuanhua and Longguan area of Hebei province, northern China. As the oldest depositional iron deposit, it is characterized by oolitic and stromatolitic ironstone. SEM (scanning electron microscope) and EMPA (electron microprobe analysis) show that most ferruginous colds are composed of continuous and concentric sheaths (cortices) Which are made up of dark and light layers. These layers are made of flakes, platelets, and granules of hematite or siderite and show large variation in major oxide compositions, especially in FeO and SiO2,contents. The average of FeO and SiO2, in the dark layers is 94.982% and 1.723%, respectively, Whereas in the light ones are 78.533% and 29.969%. SiO2, Al2O3, K2O and CaO are concentrated in the light layers but depleted in the dark ones. Compared their internal fabric with recent and ancient carbonate colds, combined with environmental characteristics and plentiful microfossil found in the colds, it is likely that both microorganism and fluctuation setting are helpful for the generation of oolitic ironstone.

关键词： GEOCHEMISTRY AND MICROFABRIC OF OOliTIC IRONSTONE IN THE XUANLONG AREA OF HEBEI PROVINCE NORTHERN CHINA FeO

The position of Cathaysia in Nuna and during the Nuna-Rodinia transition

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Science Bulletin 2024年第17期69卷 2693-2697页

作者： Chuan Yang Zheng-xiang li Yang li Xian-Hua li State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Earth Evolution and Dynamics Research Center(EDRC) Laoshan LaboratoryQingdao 266237China Earth Dynamics Research Group(EDRG) School of Earth and Planetary SciencesCurtin UniversityPerth WA 6845Australia School of Earth and Space sciences Peking UniversityBeijing 100871China State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The assembly and breakup of Nuna and Rodinia, two successive supercontinents in the Proterozoic, provide key evidence for the establishment of supercontinent cycles. Reliable palaeogeographic reconstructions at the cores of the two supercontinents are critical for understanding the evolution and geodynamics of the supercontinent cycles. In addition, there are fundamental aspects of the Nuna-Rodinia transition that remain poorly understood, including the ways in which Nuna broke up and Rodinia assembled, either through introversion [1] or extroversion [2].

关键词： continent Rodinia transition

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Three-dimensional reconstruction of Late Miocene Trapa from eastern Zhejiang Province,China:Insights into its phytogeography and evolution

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Journal of Palaeogeography 2024年第4期13卷 954-970页

作者： liang Xiao Man Yuan De-Shuang Ji li-Yan Guo xiang-Chuan li Xing Wang Jia-Nan Wang Jia-Qi liang Mei-Ting Wang School of Earth Science and Resources and Key Laboratory of Western Mineral Resources and Geological Engineering of the Ministry of EducationChang'an University State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences Shaanxi Key Laboratory of Early life and Environments Northwest University State Key Laboratory of Continental Dynamics Northwest University

Abundant plant fossils were found in the Upper Miocene shengxian Formation,eastern Zhejiang Province,China,among which Trapa belongs to a dominant *** fossil fruits of Trapa were well preserved with abundant ***,due to compaction during fossilization,Trapa fruits were often flattened,leading to the loss of some characteristic ***,a bias in taxonomic and phylogenetic studies would occur when such studies were based on these fruit *** this study,we present the first quantitative three-dimensional reconstruction of compressed Trapa fruit fossils to restore their original morphology prior to *** approach provides a novel perspective for the identification and classification of compressed fruit *** three-dimensional reconstruction of Trapa fruit fossils enabled accurate comparisons with extant *** subsequently identified it as a new species,named Trapa radiatiformis *** ***.,revealing differences from previously known taxa of ***,our comparison suggests that the long lower horns and residual stalk may represent inherent characteristics of early Trapa ***,these traits gradually degenerated during fruit evolution,resulting in morphological simplification during geological *** with primitive features exhibits good resemblance to Trapa natans fruit characteristics,which means it may be an ancestor of *** summarize the palaeogeographic distribution of fossil Trapa using previously published literature and demonstrate that the genus was mostprosperous in the Miocene and exhibited the same distribution as that at ***,through detailed morphological comparisons between Trapa and Hemitrapa fruits,along with phylogenetic analysis within the Primotrapa genus itself,we propose a homology between Trapa and Hemitrapa,suggesting that they could have a common ancestor.

关键词： Trapa Late Miocene shengxian Formation Three-dimensional reconstruction Phytogeographic history Evolutionary history

Cassiterite U-Pb dating of the Yelonggou pegmatite-type lithium deposit in western Sichuan and its metallogenic age constraints

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China geology 2024年第1期7卷 153-156页

作者： xiang-yuan Yue Qian Zhang Jun-jun Zhang Wei Zhang Jing Zhang Zhi-quan Jia li-ping Luo institute of Multipurpose Utilization of Mineral Resources Chinese Academy of Geological SciencesChengdu610041China Shandong Lunan geology and Exploration institute(No.2 Brigade of Shandong BGMR) Jining272100China Sichuan Shudao Advanced Material Science Group Co.Ltd. Chengdu610041China No.3 Geological Brigade of Sichuan Province Chongzhou611230China

*** Pegmatite hosts important resource of rare metals,e.g.,lithium(li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type deposits,for which accurate dating of pegmatite formation and mineralization is *** Songpan-Ganzi orogenic belt is a major rare metal metallogenic belt in China,hosting many important pegmatite-type li deposits,including the lijiagou,Dangba,Jiajika,Yelonggou,Cuola,and *** age data(mica Ar-Ar and zircon/cassiterite U-Pb)from these li deposits are sparse,ranging from 210 to 152 ***,obtaining reliable zircon U-Pb dates can be a challenge due to the strong decidualization in *** a result,the formation and mineralization ages of these rare metal pegmatites remain controversial,which hampers the development of pegmatite-type metallogenic model for the Songpan-Ganzi orogenic belt.

关键词： dating metallogenic zircon

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Precise isotopic measurements of sub-nanogram Nd of standard reference material by thermal ionization mass spectrometry using the NdO+ technique

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Precise isotopic measurements of sub-nanogram Nd of standard...