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Acta Geologica Sinica(English Edition) 2013年第3期87卷 730-737页

作者： QIAO Xiufu GUO Xianpu State Key Laboratory of Continental Tectonics and Dynamics Institute of Geology Chinese Academy of Geological Sciences

The early jurassic soft-sediment deformation occurring within lacustrine sandstone is distributed mainly in the Wuqia region of SW Tianshan Mountains, Xinjiang, western China. Triggered by earthquakes, such deformation was found to occur in three beds overlying the lower jurassic Kangsu Formation. The main styles of deformation structures comprise load cast, ball-and- pillow, droplet, cusps, homogeneous layer, and liquefied unconformity. The deformation layers reflect a series of three strong earthquakes at the end of early jurassic in the Wuqia region. The differences of deformation mechanisms undergone might represent the varying magnitudes of the earthquake events. During the early jurassic, the Wuqia region was located in a pull-apart basin controlled by the significant Talas-Ferghana strike-slip fault in central Asia, which initiated the soft-sediment deformation induced by earthquakes. Our research suggests that the paleoseismic magnitudes could have ranged from Ms 6.5 to 7.

关键词： early jurassic seismicity load droplet liquefied unconformity Talas-Ferghana fault Xinjiang

early jurassic Coleopterans from the Mintaja Insect Locality,Western Australia

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 925-953页

作者： Sarah K.MARTIN School of Geosciences Building 28Monash UniversityClayton Victoria 3800Australia

Beetles （Coleoptera） are the most common insects recovered from the Lower jurassic Mintaja insect locality of Western Australia, with over half of the fossils recorded from this site being isolated coleopteran elytra. A range of partial beetle bodies and other isolated beetle sclerites have also been recovered from the locality; much of this material is taxonomically unidenitifiable due to its disarticulation and poor preservation. A number of the Mintaja coleopterans are assigned to the archostematan family Ommatidae, including Zygadenia westraliensis （Riek, 1968） comb. nov, previously placed in the morphogenus Mesothoris, and an unnamed species of Tetraphalerus. Also recorded is a new species of elaterid, Lithomerus wunda sp. nov., along with other fragments likely attributable to the same family. The remaining material is assigned into morphospecies, separated primarily on preserved body parts - specifically, there are three morphospecies based on partially articulated coleopteran bodies, two morphospecies based on isolated head capsules, three morphospecies based on isolated thoracic sclerites, three morphospecies based on isolated abdominal sclerites, and 13 morphospecies based on isolated elytra. Overall, the ecology of these fossils is difficult to interpret due to poor preservation, although some of the beetles were likely aquatic, and the Ommatidae and Elateridae were both likely xylophilous. There is a strong similarity between the Mintaja coleopterans and those from the Late Triassic Denmark Hill locality of Queensland, though many of these similarities are based on morphotaxa and may be superficial in nature. Of the species that have been assigned to named taxa, all are generally typical of the Late Mesozoic worldwide, with Zygadenia, Tetraphalerus and Lithomerus all long-ranging, cosmopolitan genera.

关键词： Coleoptera early jurassic Mintaja insect locality Western Australia

Identification of the early jurassic mylonitic granitic pluton and tectonic implications in Namling area,southern Tibet

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Geoscience Frontiers 2021年第1期12卷 13-28页

作者： Yuanku Meng Walter D.Mooney Runlong Fan Jinqing Liu Youqing Wei College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China U.S.Geological Survey Menlo ParkCA 94025USA SHRIMP Center Institute of GeologyChinese Academy of Geological SciencesBeijing 102206China

A number of studies revealed that the Gangdese magmatic belt of southern Tibet was closely related to the northward subduction of the Neo-Tethys oceanic lithosphere and Indo-Asian ***,pre-Cretaceous magmatism is still poorly constrained in the Gangdese magmatic belt,southern ***,we conducted systematically geochronology and geochemistry studies on a newly-identified granitic pluton in the middle Gangdese magmatic belt(Namling area),southern *** SHRIMPⅡU-Pb dating for one representative sample gives a weighted age of 184.2±1.8 Ma(MSWD=±1.11),corresponding to emplacement and crystallization age of the granitic pluton in the early jurassic(Pliensbachian).High SiO2(68.9-72.1 wt.%)contents and intermediate Mg#values(35-38)together suggest that the newly-identified granitic pluton was probably formed by partial melting of crustal material with minor injection of mantle-derived magma,precluding an origin from melting of metasedimentary rocks that are characterized by low Mg#and high zirconδ^18O values(>8‰).Geochemically,the newly-identified granitic pluton belongs to typical I-type granitic affinity,whereas this is inconsistent with aluminium saturation index(ASI=A/CNK ratios)and geochemical *** suggests that zircon oxygen isotopes(4.30‰-5.28‰)and mineral features(lacking Al-rich minerals)are reliable indicators for discriminating granitic *** depleted whole-rock Sr-Nd-Hf isotopic compositions and zirconεHf(t)values indicate that the granitic pluton was derived from partial melting of depleted arc-type *** addition,the granitic pluton shows zirconδ^18O values ranging from 4.30‰to 5.28‰(with a mean value of 4.77‰)that are consistent with mantle-derived zircon values(5.3‰±0.6‰)within the uncertainties,indicating that the granitic pluton might have experienced weak short-living high-temperature hydrous fluid-rock *** with the Sr-Nd-Hf-O isotopes and geochemical signatures,we propose that the newl

关键词： Sr-Nd-Hf-O isotopes SHRIMP U-Pb dating early jurassic Mylonitic granitic pluton Gangdese belt

First steps in reconstructing early jurassic sea water temperatures in the Andean Basin of northern Chile based on stable isotope analyses of oyster and brachiopod shells

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Journal of Palaeogeography 2020年第1期9卷 71-87页

作者： Matthias Alberti Franz T.Fürsich Nils Andersen Institut für Geowissenschaften Christian-Albrechts-Universitat zu KielLudewig-Meyn-Straβe 1024118 KielGermany GeoZentrum Nordbayern Fachgruppe PalaoUmweltFriedrich-Alexander-Universitat Erlangen-NürnbergLoewenichstraβe 2891054 ErlangenGermany Leibniz Laboratory for Radiometric Dating and Stable Isotope Research Christian-Albrechts-Universitat zu KielMax-Eyth-Straβe 1124118 KielGermany

The stable isotope(δ13 C,δ18 O)composition of a collection of Lower jurassic brachiopods and oysters from the Andean Basin of northern Chile was *** results allow the first reconstruction of absolute water temperatures for several ammonite zones in the Lower jurassic of South *** temperature record starts with comparatively high values in the Late Sinemurian(average:27.0℃;Raricostatum Zone).Just before the Sinemurian–Pliensbachian transition,temperatures dropped to an average of 24.3℃.The lowest temperature value in the dataset was recorded for a brachiopod shell of the latest Pliensbachian Spinatum Zone(19.6℃).No data are available for the early Toarcian,but results for the late Toarcian show again comparatively warm conditions(average:24.4℃;Thouarsense–Levesquei zones).Even though more material and analyses are necessary to corroborate the recorded temperatures,the present dataset seems to indicate the global nature of the Late Pliensbachian Cooling *** contrast,the global warming during the Toarcian Oceanic Anoxic Event has not been recorded due to a lack of early Toarcian ***δ13 C record of brachiopods and oysters documents a gradual increase in values representing background *** shells were used for high-resolution stable isotope analyses and show seasonal temperature fluctuations over a period of around 3 years in the life time of the *** explained only by temperatures,theδ18 O values point to a minimum estimate for the seasonality in the late Toarcian of slightly more than 3℃.

关键词： early jurassic Chile Stable isotopes Palaeoclimate Water temperatures Seasonality

Petrogenesis of the early jurassic Longtang and Menglong Peraluminous Granites in Tengchong Terrane,and their Tectonic Implication

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1979-1990页

作者： WANG Guochang LIU Zheng TAN Shucheng HE Xiaohu WANG Yuchao QI Changshi YE Hui Institute of Palaeontology Yunnan Key Laboratory for PalaeobiologyMEC International Joint Laboratory for Palaeobiology and PalaeoenvironmentYunnan UniversityKunming 650500China School of Earth Science Yunnan UniversityKunming 650500China Institute of International Rivers and Eco-security Yunnan UniversityKunming 650500China

A comprehensive study of zircon U-Pb geochronology,in situ Hf isotopes,whole-rock major and trace element geochemistry,and Nd isotopes was carried out for two early jurassic two-mica granites(Longtang and Menglong)in the southern part of the Tengchong terrane,which is in the northern part of the larger Sibumasu *** assess the origin of the granites and explore their possible genetic relationship to the Paleo-Tethyan ***-ICP-MS zircon U-Pb dating shows that they were simultaneously emplaced in the early jurassic(ca.199 Ma).They have SiO2 contents of 69.7–75.1 wt%and are mainly strongly peraluminous with alumina saturation index(ASI)values ranging from 1.06 to *** show similar Mg#(0.29–0.42)to experimental partial melts of metasedimentary rocks under continental pressuretemperature(P-T)*** are enriched in light rare earth elements(LREEs)relative to heavy rare earth elements(HREEs),with moderately negative Eu anomalies and flat HREEs *** show negativeεNd(t)values(−9.0 to–12.4)andεHf(t)values(−8.0 to−9.1).Elemental and isotopic data suggest that they most likely to formed by muscovitedehydration melting of a metapelitic source at lower temperatures in the range of 700℃to 750℃.The granites might represent a post-collisional tectonic setting response to Paleo-Tethyan regime.

关键词： peraluminous granites post-collision early jurassic Paleo-Tethys Tengchong terrane

Braincase Anatomy of the Basal Theropod Sinosaurus from the early jurassic of China

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Acta Geologica Sinica(English Edition) 2014年第6期88卷 1653-1664页

作者： XING Lida Ariana PAULINA-CARABAJAL Philip J.CURRIE XU Xing ZHANG Jianping WANG Tao Michael E.BURNS DONG Zhiming School of the Earth Sciences and Resources China University of Geosciences Museo Carmen Funes Consejo Nacional de Investigaciones Científicas y TecnológicasAv.Córdoba 55 (8318)Plaza Huincul Neuquén Argentina University of Alberta CW405 Biological Sciences BuildingEdmonton Alberta T6G 2E9 Canada Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Lufeng Land and Resources Bureau

The neuroanatomy of the mid-sized theropod Sinosaurus triassicus from the Lower jurassic Lufeng Formation, Lufeng Basin in Yunnan Province, China was studied using X-ray computed tomography. The braincase is characterized by a large supraoccipital knob that is capped by a posterior projection of the parietal and two external foramina for the caudal middle cerebral vein, which is completely enclosed by the supraoccipital. The basicranium has well defined, short basipterygoid processes that project ventral to the basal tubera. The basisphenoid is expanded, projects posteroventrally, and is pierced by four pneumatic recesses. The endocranial morphology resembles that observed in other basal theropods—in particular some allosauroids—and has a strongly marked pontine flexure and a large dorsal expansion. The inner ear morphology is also similar to that observed in other basal theropods, with slender semicircular canals. The anterior semicircular canal is 20% larger than the posterior semicircular canal, and the angle formed between them is less than 90° when seen in dorsal view.

关键词： Neuroanatomy paleoneurology Dinosaur inner ear pneumaticity early jurassic Yunnan

Discovery of Fossil Charophytes from the Late Triassic Xujiahe Formation and early jurassic Lower Yimen Formation, Sichuan Province, and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 301-309,327页

作者： Liu Junying Chen Zhongliang Institute of Geology, Chinese Academy of Geological Sciences, Beijing Panxi Geological Party, Sichuan Bureau of Geology and Mineral Resources, Xichang Liu Linqun Institute of Geology Chinese Academy of Geological Sciences Beijing China

This paper describes the fossil charophytes collected from the Late Triassic Xujiahe Formation in Dazuand early jurassic Lower Yimen Formation in Xichang, Sichuan Province, and their significance. Up to now,papers dealing with fossil charophytes of the Late Triassic, especially of the early jurassic, have been rarelypublished. The description of the two new species of Porochara, P. dazuensis and P. xichangensis, and theirfossil assemblage not only provides an important basis for classification and correlation of red beds insouthwestern China but reveals for the first time the features of the charophyte flora of the Late Triassic-earlyjurassic in the area, thus offering valuable data for the establishment of Triassic and jurassic charophyte fossilzones in China.

关键词： Sichuan Late Triassic early jurassic charophyte fossil

New Evidence of Sauropod Dinosaurs from the early jurassic Period of Thailand

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1169-1178页

作者： LAOJUMPON Chalida SUTEETHORN Varavudh CHANTHASIT Phornphen LAUPRASERT Komsom SUTEETHORN Suravech Department of Biology Faculty of Science Mahasarakham University Khantarawichai Mahasarakham 44150 Thailand Palaeontological Research and Education Centre Mahasarakham University Khamrieng Maha Sarakham 44150 Thailand Sirindhorn Museum Department of mineral resources SahatSakhan Kalasin 46310 Thailand

The oldest dinosaur assemblages of Thailand deposit in continental sedimentary rocks of the Nam Phong Formation. Not only Isanosaurus attavipatchi was discovered but at least two more species of basal sauropods were found. A partial skeleton from Phu Hin Tan locality refers to sauropod taxon A. It is different from Isanosaurus and shares some characteristics with basal sauropods in the early jurassic. The sauropod taxon B was found in Non Sra Ard locality. Base on postcranial skeleton, sauropod taxon B shares some characteristics of the family Vnlcanodontidae. Moreover, several fragments of the sauropods specimen are also found in Pha Khok Wang Yang and Phu Noi localities. All of the evidences above indicate that there are a highly diversity of sauropods in the Nam Phong Formation. At least three sauropod species （including Isanosaurus） were found in the Nam Phong formation. The issue about the age of the Nam Phong has been debated for a long time between the Triassic and jurassic age. All of sauropodomorphs, in this study, are more likely the early jurassic period dinosaurs than the Triassic period dinosaurs. And they have deposited in the upper part of Nam Phong Formation.

关键词： Isanosaurus sauropod dinosaurs early jurassic Nam Phong Formation Thailand

NEW early jurassic ACTINOPTERYGIANS FROM WEIXIN,YUNNAN

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古脊椎动物学报(中英文） 1994年第3期 162-165页

作者： Su Dezao (Institute of Vertebrate Paleontology and Paleoanthropology,Academia Sinica Beijing 100044)

The actinopterygian specimens described here were collected from Weixin, Yunnan by the Regional Geological Surveying Brigade of Guizhou Province. It was alleged that all the 25 specimens were discovered from "Xiangxi Formation" (Lower jurassic). Four of them are assigned to a new genus and species, Weixiniscus microlepis, of the Pa1aeoniscidae. The others are referred to a new genus and species,Zaxilepis qinglongensis, of the Archaeomaenidae. Previously archaeomaenids were known only from Australia and Antarctica of Gondwanaland, this new discovery is of significance in the understanding of the distribution of Mesozoic freshwater fishes.

关键词： Weixin,Northeastern Yunnan early jurassic Palaeoniscidae,Archaeomaenidae

Comparison of early jurassic flora from South Primorye of Russia with its main coeval floras of China

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Global Geology 2013年第1期16卷 19-25页

作者： Elena Salyukova Elena Volynets SUN Ge Svetlana Shorokhova Research Center of Paleontology & Stratigraphy Jilin University Institute of Biology and Soil Science FEB RAS Vladivostok 690022Russia College of Paleontology of Shenyang Normal University Far East Federal University Vladivostok 690060Russia

The early jurassic flora,with over 42 species of 26 genera and documented in age by sandwiched marine beds,from the Lower jurassic Schitukhe Formation of South Primorye,Russia,is further *** flora is dominated by cycadophytes,ferns and conifers,with some of ginkgoales and czekanowskiales,and characterized by occurrence of Cycadocarpidium,with very rare Coniopteris.A comparison of this flora with its coeval early jurassic floras of China is *** Russian flora is considered as the early assemblage of early jurassic flora,and more similar to the early jurassic floras from the Shansonggang-and Yihe formations of Jilin,Beipiao Formation of Liaoning,and lower-middle Guanyintan Formation of Hunan in China.

关键词： early jurassic Schitukhe flora South Primorye Russia China