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A Possible long-tailed Bird with a Pygostyle from the late Mesozoic Yixian Formation, Western liaoning, China

Acta Geologica Sinica(English Edition) 2005年第1期79卷 7-10页

作者： l junchang1 and hou lianhai2.1 institute of geology, Chinese Academy of Geological Sciences, beijing 100037 2.{2. of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, beijing 100044 Department of Biology, Capital Normal University, beijing 100037 Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China Chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China Capital Normal Univ Dept Biol Beijing 100037 Peoples R China

An incomplete caudal vertebral series (IVPP V11309) from the Yixian Formation of late Mesozoic, Jianshangou area of Beipiao, western liaoning Province, may represent a new bird. The tail is composed of at least 12.free caudal vertebrae and the most distal 5 caudal vertebrae co-ossified into a pygostyle. The pygostyle is plate-like and slightly curved dorsally. The anterior free caudals are amphiplatyan. The anterior caudal surfaces of the last three free caudals are concave, but their posterior articular surfaces are convex. The pygostyle is regarded as the first appeared flight apparatus during the evolutionary process from Archaeopteryx to neornithes. The pygostyle appeared in most early fossil birds and almost all the modern birds. Although their morphologies are different, they are basically formed by at least four last caudal vertebrae. The specimen V11309 is regarded as a bird rather than a non-avian theropod dinosaur based on the following characters: short caudal vertebrae, numerous pits present on the surfaces of the centra and, a foramen present between the basal part of the fused neural spines, which is similar to that of Struthio camelus. The discoveries of pygostyles from the therizinosauroids and oviraptorosaurs may provide strong evidence for supporting the origin of birds from small theropod dinosaurs. The structure of the pygostyle in specimen V11309 is different from those of Beipiaosaurus (Therizinosauroid) and Nomingia (oviraptorosaur). The most parsimonious interpretation is that these pygostyle-like structures are independently acquired by Beipiaosaurus and Nomingia during their evolutionary process.

关键词： western liaoning Yixian Formation late Mesozoic pygostyle

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Discovery of Cu-Zn,Cu-Sn intermetallic minerals and its significance for genesis of the Mianning-Dechang REE Metallogenic Belt,Sichuan Province,China

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Science China Earth Sciences 2006年第6期49卷 597-603页

作者： XIE Yuling1, hou Zengqian2. XU Jiuhua1, YUAN Zhongxin2. BAI Ge2.& lI Xiaoyu3 1. Civil and Environmental Engineering School, University of Science and Technology beijing, beijing 100083, China 2. {2. of geology, Chinese Academy of Geological Sciences, beijing 100037, China 3. The 109th Geological Team, Sichuan Bureau of Mineral Exploration, Chengdu 610100, China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing China institute of geology Chinese Academy of Geological Sciences Beijing China The 109th Geological Team Sichuan Bureau of Mineral Exploration Chengdu China

Mianning-Dechang Himalayan REE Metallogenetic Belt in Sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2.n), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

关键词： Mianning-Dechang REE metallogenetic belt, Cu-bearing intermetallic minerals, EPMA, genesis significance, deep source magmatic activity.

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Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science China Earth Sciences 2004年第3期47卷 221-231页

作者： hou Zengqian1, QU Xiaoming1, WANG Shuxian2. DU Andao2. GAO Yongfeng3 & HUANG Wei4 1. institute of Mineral Resources, Chinese Academy of Geological Sciences,{2., China 2. National Center of Geoanalysis, Chinese Academy of Geological Sciences,{2., China 3. Shijiazhuang College of Economy, Shijiazhuang 056000, China 4. Xizang Bureau of geology and Mineral Resources, lhasa 850000, China institute of Mineral Resources Chinese Academy of Geological Sci. Beijing 100037 China National Center of Geoanalysis Chinese Academy of Geological Sci. Beijing 100037 China Shijiazhuang College of Economy Shijiazhuang 056000 China Xizang Bureau of Geol./Mineral Rsrc. Lhasa 850000 China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.2.) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.2.) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 2.—2. Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

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low Resource Chinese Geological Text Named Entity Recognition Based on Prompt learning

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Journal of Earth Science 2024年第3期35卷 1035-1043页

作者： Hang He Chao Ma Shan Ye Wenqiang Tang Yuxuan Zhou Zhen Yu Jiaxin Yi li hou Mingcai hou State Key laboratory of Oil and Gas Reservoir geology and Exploitation Institute of Sedimentary GeologyCollege of Computer Science and Cyber SecurityChengdu University of TechnologyChengdu 610059China Key laboratory of Deep-Time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China School of Information Engineering China University of Geosciences(Beijing)Beijing 100083China

Geological reports are a significant accomplishment for geologists involved in geological investigations and scientific research as they contain rich data and textual *** the rapid development of science and technology,a large number of textual reports have accumulated in the field of ***,many non-hot topics and non-English speaking regions are neglected in mainstream geoscience databases for geological information mining,making it more challenging for some researchers to extract necessary information from these *** language Processing(NlP)has obvious advantages in processing large amounts of textual *** objective of this paper is to identify geological named entities from Chinese geological texts using NlP *** propose the RoBERTa-Prompt-Tuning-NER method,which leverages the concept of Prompt learning and requires only a small amount of annotated data to train superior models for recognizing geological named entities in low-resource dataset *** RoBERTa layer captures context-based information and longer-distance dependencies through dynamic word ***,we conducted experiments on the constructed Geological Named Entity Recognition(GNER)*** experimental results show that the proposed model achieves the highest F1 score of 80.64%among the four baseline algorithms,demonstrating the reliability and robustness of using the model for Named Entity Recognition of geological texts.

关键词： Prompt learning Named Entity Recognition(NER) low resource geological text text information mining big data geology.

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liaoxiornis delicatus *** ***.,the smallest Mesozoic bird

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Chinese Science Bulletin 1999年第9期44卷 834-838页

作者： hou lianhai and CHEN Peiji {2. of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences , {2. 100044, China Nanjing {2. of geology and Paleontology, Chinese Academy of Sciences , China institute of Vertebra Paleontology und Paleoanthropology Chinese Academy of Sciences Beijing China Nanjing Instittue of Gology and Paleontology Chinese Academy of Sciences China

Recently, a very small and complete bird specimen was collected from the Confuciusornis-bearing Yixian Formation. This finding represents a new kind of Mesozoic bird, named liaoxiornis delicatus. It is characterized by a short skull with teeth, a long neck and a very small sternum with only posterior process; the humeral head is not internally curved, and the hindlimbs are longer than the forelimbs. liaoxiomis delicatus is not only much smaller than Confuciusornis, but also smaller than Cathayomis and other early Cretaceous birds. It is the smallest bird known from Mesozoic deposit. liaoxiornis provides new evidence indicating that the early adaptive radiation of birds is complicated.

关键词： Mesozoic early bird evolution of birds.

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Spatiotemporal variation of rainy season span and precipitation recorded by lacustrine laminated pollen in the Tibetan Plateau during the past two millennia

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Science China Earth Sciences 2024年第3期67卷 789-801页

作者： Anning CUI houyuan lU Juzhi hou Xingqi lIU Deke XU Key laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Group of Alpine Paleoecology and Human Adaptation State Key Laboratory of Tibetan Plateau Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Capital Normal University College of Resource Environment and Tourism Beijing 100048China

The quantitative reconstruction of the length of the rainy season and precipitation on the Tibetan Plateau(TP) is crucial for revealing the spatiotemporal evolution of the Westerlies and Asian summer monsoon, as well as its ecological and environmental effects. Accurately determining the start and end times of the rainy season on the Plateau remains *** study determined the start and end times of the rainy season in different locations on the Plateau by identifying precipitation inflection points. We calculated the duration and precipitation amount of the rainy season and established a transfer function between the modern pollen assemblages and them. Then, we reconstructed the rainy season variations in Kusai lake(northern TP) and Jiang Co(central TP) during the past two millennia. The results showed that, the rainy season precipitation in Kusai lake recorded five periods of high precipitation: AD 580–680, 1000–1100, 12.0–1450, 1550–1780, and 192.–present, corresponding to the stages with long rainy season. The rainy season precipitation sequence in Jiang Co recorded four periods of high precipitation: AD 80–500, 800–950, 12.0–1450, and 1780–present, which is consistent with the long rainy season before AD 1000 but unclear afterward. Spatially, rainy season precipitation on the Plateau exhibited four patterns: “wet in both north and south” may be related to abnormally strong summer monsoons;“dry in both north and south” likely associated with weak Westerly wind and weak summer monsoon;“wet in the south and dry in the north” linked to strong summer monsoon and weak Westerly wind;and “dry in the south and wet in the north” connected to weak summer monsoon and strong Westerly wind. This study revealed the spatiotemporal evolution pattern of the rainy season onset and end, duration, and precipitation amount on the Plateau over the past two millennia. It provides natural background support for further understanding the coupling between Westerly wind and Asia

关键词： Tibetan Plateau Past two millennia Rainy season length Rainy season precipitation Quantitative reconstruction

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Two thin middle-crust low-velocity zones imaged in the Chuan-Dian region of southeastern Tibetan Plateau and their tectonic implications

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Science China Earth Sciences 2024年第5期67卷 1675-1686页

作者： long lI Xin WANG Guangbing hou Yuan lING Yinshuang AI Key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China

Intracrustal low-velocity zones(lVZs)indicate a mechanically weak crust and are widely observed in the southeast margin of the Tibetan ***,their spatial distributions and formation mechanisms remain *** investigate their distribution and detailed morphology of the lVZs in the southeastern Tibetan Plateau,here we used teleseismic events and continuous waveform data recorded by 40 broadband seismic stations newly deployed in the Sichuan-Yunnan region from December 2.18 to October 2.2..A total of 12.92. high-quality P-wave receiver functions and 5–40 s fundamental Rayleigh surface wave phase velocity dispersion curves from ambient noise cross-correlation functions were *** Swave velocity model at a depth interval of 0–100 km in the study area was inverted by using the trans-dimensional Markov chain Monte Carlo strategy to jointly invert the complementary data of the receiver function waveform and Rayleigh surface wave phase velocity *** results show that there are two separate lVZs(~3.5 km/s)surrounding the rigid Daliangshan subblock at crustal depths of approximately 30–40 km,providing new constraints on the geometry of the lVZs in our study *** two lVZs obtained in this study may represent the middle crustal flow channels,through which the material in the center of the Tibetan Plateau extrudes to its southeast *** by the rigid Sichuan Basin and the spindle-like Daliangshan subblock,the material continues to flow southward through the mechanically weak middle crustal channels surrounding the Daliangshan *** addition,the existence of thin lVZs in the middle crust plays an important role in understanding the decoupling between the upper and lower crust in the study *** also provides new constraint on the complex tectonic deformation process of the southeastern margin of the Tibetan Plateau caused by the collision and compression of the Indian and the Eurasian plates.

关键词： Southeastern Tibetan Plateau Joint inversion Intracrustal low-velocity zone Mid-crustal channel flow

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Investigation on the Deformation and Failure Patterns of loess Cut Slope Based on the Unsaturated Triaxial Test in Yan'an,China

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Journal of Earth Science 2024年第1期35卷 235-247页

作者： lina Ma Shengwen Qi Songfeng Guo Qiangbing Huang Xiaokun hou Key laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Department of Geological Engineering Chang'an UniversityXi'an 710054China

The large-scale implementation of the Gully Stabilization and land Reclamation(GSlR)project induces various failures of loess slopes due to excavation in Yan'an,***,the deformation and failure behavior of these excavated loess slopes have not been fully *** this study,field investigation was undertaken for analyzing the distributions and failure features of excavation-induced loess slope *** is found that plastic failure mainly occurs in Q_(3) loess layers and brittle failure in Q_(2..To understand the underlying failure mechanism,a series of triaxial shear tests were conducted on intact Q_(3) and Q_(2. loess samples that with different water contents,namely natural water content(natural),dry side of the natural value(drying 5%),and wet side(wetting 5%).The characteristics of stress-strain curves and failure modes of the samples were *** show that the stress-strain curves of Q_(2. samples are dominated by strain-softening characteristics,while Q_(3) samples mainly exhibit strain-harden features except in the drying ***,shear failures of Q_(3) specimens are mainly caused by shear crack planes(single,X or V-shaped).For Q_(2. loess,the dominance of tensile cracks is observed on the surface of damaged *** disclose the different failure modes of excavated slopes located in different strata,that is,the arc sliding failure of Q_(3) loess slopes and the stepped tensile failure of Q_(2. loess slopes,and are helpful in the design and management of the ongoing GSlR projects in the loess Plateau.

关键词： loess slope slope stability failure patterns deformation

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geology and Geochemistry of K-feldspar Veins in lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold Mineralization

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 104-116页

作者： ZHANG Huichao CHAI Peng ZHANG Hongrui Zhou limin hou Zengqian Key laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China institute of geology Chinese Academy of Geological SciencesBeijing 100037China Key laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China National Research Center for Geoanalysis Beijing 100037China

lamprophyres typically appear in hydrothermal gold *** relationship between lamprophyres and gold deposits is investigated *** researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in ***,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold *** in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2.li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in *** in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from *** large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched *** veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit.

关键词： lamprophyre K-feldspar vein apatite Sr isotope gold Zhenyuan deposit Yunnan

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A NEW PAlEOCENE BIRD FROM ANHUI, CHINA

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古脊椎动物学报(中英文） 1994年第1期 64-65页

作者： hou lianhai ({2. of Vertebrate Paleontology and Paleoanthropology, Academia Sinica {2. 100044)

In 1991, a fossil brid represented by three bones of the same individual was obtained by Prof. li Chuankui from Qianshan Distrift, Anhui Province. This discovery documents the first record of Rallidae from the Paleoce... 详细信息

关键词： Qianshan, Anhui Paleocene Rallidae

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