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古脊椎动物学报（中英文） 2024年第3期62卷 225-244页

作者： KE Yi-Hui PEI Rui XU Xing Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences Beijing 100044 College of Earth and Planetary Sciences University of Chinese Academy of Sciences Beijing 100049 Centre for Vertebrate Evolutionary Biology Yunnan University Kunming 650091

The Tyrannosauridae,which is characterized by specialized pachydont dentition and putative bone-cracking predatory strategies,is one of the most extensively studied theropod *** tooth replacement patterns,crucial for understanding feeding behaviors,have been thoroughly studied in this group,studies on non-tyrannosaurid tyrannosauroids are relatively *** study utilizes high-resolution CT data to investigate the tooth replacement pattern in two specimens of Guanlong wucaii,a late jurassic tyrannosauroid,and provides insights into the evolution of tooth replacement across ***-generation replacement teeth,a rarity observed mainly in giant predatory theropods(*** tyrannosaurids),were detected in the dentary dentition of the juvenile *** reconstructions display a consistent cephalad alternating tooth replacement pattern in the maxilla and the dentary of both of the examined individuals,with Z-spacing values exceeding *** Guanlong grows,the Z-spacing value in the maxillary dentition increases,resembling the ontogenetic changes documented in the ***,like Tarbosaurus,Guanlong also displays a discontinuity between the tooth replacement waves at the premaxilla-maxilla *** study thus demonstrates that some tyrannosaurid-like tooth replacement patterns were acquired before the origin of the Tyrannosauridae.

关键词： late jurassic Tyrannosauroidea tooth replacement 3D reconstruction

late jurassic Volcanism Deduced from Geochemical,Geochronological,and Sr-Nd-Hf Isotopic Composition Characteristics of the Nanyuan Formation,South China

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Acta Geologica Sinica(English Edition) 2023年第2期97卷 449-468页

作者： WANG Dongsheng LI Jinwen SHE Hongquan WANG Kunming YANG Junzhi REN Chenghao MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences(CAGS)Beijing 100037China Forestry and Grassland Administration of Shanxi Province Taiyuan 030021China

The Nanyuan Formation contains information related to the Mesozoic tectonic *** this study,three representative profiles were surveyed from the Nanyuan Formation,and multiple analyses were *** U-Pb dating yielded their ages as approximately 158–146 *** volcanic rocks are enriched in Rb,Th,U,K,and Pb and depleted in Nb,Ta,P,and Ti,implying their affinity for I-type ***εNd(t)values(-8.3 to-6.0),^(87)Sr/^(86)Sr)i values(0.7077–0.7094)of the volcanic rock,andεHf(t)values(-8.71 to 0.12)of the Mesozoic zircons suggest that the Nanyuan Formation magma originated in the lower crust with the involvement of depleted mantle *** parent rocks of the rhyolitic and dacitic volcanic rocks formed by partial melting of basement rocks in South China and the andesitic volcanic rocks were derived from partial melting of the metasomatites generated by slab-mantle *** fractional crystallization also played an important role in later *** diagrams of the volcanic rocks indicated that they formed in a volcanic arc *** with previous data,the Nanyuan Formation recorded subduction of the Paleo-Pacific Plate before regional tectonic *** compressive stress field endured until the end of the late jurassic.

关键词： late jurassic Nanyuan Formation volcanic rocks volcanic arc geochemistry petrogenesis Pinghe

late jurassic PROTOSUCHIAN SICHUANOSUCHUS HUIDONGENSIS (ARCHOSAURIA: CROCODYLIFORMES) FROM ZIGONG, SICHUAN, CHINA

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古脊椎动物学报(中英文） 1996年第4期 277-278页

作者： PENG Guanghao(Zigong Dinosaur Museurn Zigong Sichuan 643013)

Peng (1995) briefly reported a specimen (ZDM3403) of seuanamchus hutwsisPeng, 1995, a protosuchian from the purplish-red mudstone of the late jurassic ShangshaximiaoFonnahon at Daquekou, the suburb of Zigong City. This material is the first occurrenceof the prot0suchian from the Ute JamSSic in Sichuan ffesin and the most well-preservedprotosuchian tbSSl ever found in China’ The pmt paper is a detaital bophon of it.

关键词： Zigong Sichuan Shangshaximiao Formation late jurassic Protosuchian

Geochronology,Petrogenesis and Tectonic Setting of the late jurassic I-type Granites in the North Qinling Orogenic Belt,Central China

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Acta Geologica Sinica(English Edition) 2023年第4期97卷 1132-1149页

作者： HUANG Yanna LI Dunpeng XIAO Aifang XU Songming College of Zijin Geology and Mining Fuzhou UniversityFuzhou 350108China

The North Qinling Orogenic Belt(NQOB)is a composite orogenic belt in central *** started evolving during the Meso-Neoproterozoic period and underwent multiple stages of plate subduction and collision before entering intra-continental orogeny in the late *** Meso-Cenozoic intra-continental orogeny and tectonic evolution had different responses in various terranes of the belt,with the tectonic evolution of the middle part of the belt being particularly *** granites distributed in the Dayu and Kuyu areas in the middle part of the NQOB can provide an important window for revealing the geodynamic mechanisms of the *** main lithology of Dayu and Kuyu granites is biotite monzogranite,and the zircon U-Pb dating yielded intrusive ages of 151.3±3.4 Ma and 147.7±1.5 Ma,*** dates suggest that the biotite monzogranite were formed at the end of the late *** whole-rock geochemistry analysis shows that the granites in the study areas are characterized by slightly high SiO_(2)(64.50-68.88 wt%)and high Al_(2)O_(3)(15.12-16.24 wt%)and Na_(2)O(3.55-3.80 wt%)*** are also enriched in light rare earth elements,large ion lithophile elements(e.g.,Ba,K,La,Pb and Sr),and depleted in high field strength elements(HFSEs)(e.g.,Ta,Nb,P and Ti).Additionally,the granites have weakly negative-slightly positive Eu anomalies(δEu=0.91-1.19).Zircon Lu-Hf isotopic analysis showedε_(Hf)(t)=-6.1--3.8,and the two-stage model age is T_(2DM(crust))=1.5-1.6 *** granites in the study areas are analyzed as weak peraluminous high-K calc-alkaline I-type *** formed by partial melting of the thickened ancient lower crust,accompanied by the addition of minor mantle-derived *** magma ascent,they experienced fractional crystallization,with residual garnet and amphibole for a certain proportion in the magma source *** the geotectonic data suggest that the end of the late jurassic granite magmatism in the Dayu and K

关键词： partial melting tectonic transition I-type granite late jurassic North Qinling Orogenic Belt

Sedimentary Conditions of Evaporites in the late jurassic Xiali Formation,Qiangtang Basin：Evidence from Geochemistry Records

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 156-174页

作者： SONG Chunhui ZENG Yongyao YAN Maodu FANG Xiaomin FENG Ying PAN Jiaqiu LIU Xifang MENG Qingquan HU Chunhua ZHONG Sirui School of Earth Sciences ＆ Key Laboratory of Western China's Mineral Resources of Gansu Province Lanzhou University Lanzhou 730000 China CAS Center for Excellence in Tibetan Plateau Earth Sciences ＆ Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese of Academy of Sciences Beijing 100101 China Lanzhou Resources ＆ Environment Voc-Tech College Lanzhou 730000 China Institute of Mineral Resources Chinese Academy of Geological Sciences ＆ Key Laboratory of Saline Lake Resources and Environment Ministry of Land and Resources Beijing 100037 China

The Qiangtang Basin（QB）, located in the central Tibetan Plateau, is a jurassic marine basin and one of the most important prospective salt resource belts in China. In recent decades, many outcrops of gypsiferous bed have been found in the jurassic marine strata in the basin. Salt springs with abnormally high sodium（Na-＋） contents had been identified in the late jurassic Xiali Formation（Fm.） in the basin in the last years. However, to date, no potash or halite deposits have been identified in the QB. Gypsum outcrops and salt springs are very important signs in the investigation of halite and potash deposits. Therefore, the Xiali Fm. is a potentially valuable layer to evaluate for the possible presence of halite and potash deposits in the basin. However, few studies have explored the formation conditions of evaporites in the unit. Here, we present detailed geochemical records from the Yanshiping section related to the study of the formation conditions of evaporites in the Xiali Fm. of the QB. Climate proxies based on the obviously increased anion concentrations of SO4（2-） and Cl-- and the significant correlation coefficients of Ca2＋-SO42-（R = 0.985） and Na-＋-Cl--（R = 0.8974） reveal that the upper member of the Xiali Fm.（the upper Xiali Fm.） formed under an arid climate and evolved into the sulfate phase or early chloride phase. Provenance proxies based on the obviously increased K-＋ and Na-＋ ion concentrations and the significant correlation coefficient of Na-＋-Cl--（R = 0.8974） suggest that the upper Xiali Fm. featured optimal provenance conditions for the possible formation of halite deposits. The regression and the semi-closed tidal flat environment in the upper Xiali Fm. were favorable for the formation of potash and halite deposits. The low Mg-（2＋） /Ca-（2＋） values（mean value = 1.82） and significant Na-＋-Cl-- correlation coefficient（R = 0.8974） also suggest that the upper Xiali Fm. is the layer most likely to contain potential halite deposits. In addition, the macr

关键词： Evaporites geochemistry late jurassic Xiali Formation Qiangtang Basin

A New Genus of Fossil Cycads Yixianophyllum gen. nov. from the late jurassic Yixian Formation, Western Liaoning, China

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Acta Geologica Sinica(English Edition) 2005年第5期79卷 582-592页

作者： ZHENG Shaolin LI Nan LI Yong ZHANG Wu BIAN Xiongfei Shenyang Institute of Geology and Mineral Resources Ministry of Land and Resources Shenyang Liaoning 110032 Botanical Gardens of Xianhu Shenzhen Guangdong 518004

A new genus of fossil Cycads, Yixianophyllum gen. nov., is reported here. The specimens were collected from the southern hill of Jinjiagou village, Toudaohezi Town, Yixian County, western Liaoning Province, China. The fossil plant-beating bed belongs to the lower part, the Zhuanchengzi bed, of the Upper jurassic Yixian Formation （Yixianian）. The new genus in leaf shape, venation and epidermal structure shows a transitional form between Mesozoic Cycads （Ctenis, Nilssonia） and modem Cycads （Stangeria and Encephalartos）. Since the features of these specimens differ from any known genera of Cycads, a new generic name Yixianophyllum is proposed for these leaves. Typical species, Yixianophyllum jinjiagouense gen. et sp. nov. is described here. A supposed evolutionary tendency of Cycadean leaf-forms with Taeniopteris-type is discussed.

关键词： western Liaoning Yixian Formation late jurassic Cycads YixianophyUum gen. nov. epidermal structures

Geochemistry and Genesis of the late jurassic Granitoids at Northern Great Hinggan Range:Implications for Exploration

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 321-332页

作者： WU Guang CHEN Yanjing SUN Fengyue ZHANG Zhe LIU Ankun LI Zhitong Key Laboratory of Metallogenic Dynamics Guangzhou Institute of Geochemistry the Chinese Academy of Sciences Guangzhou 510640 China Institute of Mineral Resources the Chinese Academy of Geological Sciences Beijing 100037 China Key Laboratory of Orogen and Crust Evolution Peking University Beijing 100871 China College of Earth Sciences Jilin University Changchun 130061 China Shenyang Institute of Geology and Mineral Resources China Geological Survey Shenyang 110032 China

The Longgouhe and Ershiyizhan intrusions of the late jurassic, located in the Upper Heilongjiang Basin of the northern Great Hinggan Range, are closely related to porphyry Cu-Au mineralizations. In lithology the intrusions are quartz diorite, quartz monzodiorite and granodiorite of high-K caIc-alkaline series, with minor aspects of shoshonite series. Their SiO2 and A1203 contents range from 61.37% to 66.59% and 15.35% to 17.06%, respectively. The MgO content ranges from 2.02 % to 3.47 %, with Mg# indices of 44-59. The （La/Yb）N and Eu/Eu＊ values range from 16.85 to 81.73 and 0.68 to 0.93, respectively, showing strong differentiation rare earth element （REE） patterns similar to those of adakites. The rocks are enriched in Ba, Sr and light REE （LREE）, obviously depleted in Nb and Ta, slightly depleted in Rb and Ti, and poor in Yb and Y, with Yb and Y contents of 0.31-1.32 ppm and 4.32-12.07 ppm, respectively. As indicated by Sr/Y ratios of 67.74-220.60, the rocks are characterized by low-Y and high-Sr contents, which characterize the adakites in the world. Holistically, geochemical tracers suggest that the interested intrusions are adakitic rocks. Given that the Paleo- Asian Ocean and Mongol-Okhotsk Ocean were closed in the late Paleozoic and Permian-Middle jurassic, respectively, the interested intrusions should be formed by partial melting of delaminated crust, which had been thickened during collisional orogeny between the Siberian and Mongolian- Sinokorean continents.

关键词： adakite geochemistry late jurassic continental collision thickened crust Great Hinggan Range

late jurassic PALAEONTINIDS (HOMOPTERA: AUCHENORRHYNCHA) FROM HEBEI AND LIAONING PROVINCES IN CHINA

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Insect Science 1998年第3期11卷 222-232页

作者：任东尹继才窦文秀中国地质博物馆北京100034

Two new genera and six new species of Palaeontinidae are named and described: Liaocossus hui gen. et sp. nov., L. beipiaoensis gen. et sp. nov., L. exiguus gen. et sp. nov., *** gen. et sp. nov.. L. pingquanensis gen. et sp. nov. , and Miracossus ingentius gen. et sp. nov.. The entire body of these new fossils are perfectly preserved and enable us to fix accurately the body characteristics of primitive palaeontinids. All the specimens were collected from late jurassic Yixian Formation of Northern Hebei and Western Liaoning Provinces in China.

关键词： Homoptera Palaeontinidae late jurassic new taxa

late jurassic—EARLY CRETACEOUS BELEMNITES FROM SOUTHERN TIBET,CHINA

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古生物学报 1964年第2期 200-216页

作者： YANG TSUN-YI AND WU SHUN-BAO (Peking Geological Institute)

The belemnites described here were collected by two field parties visiting southernTibet respectively in 1960 and 1961 from(1)the Lungma—Kapula area,east of Ziang-zhi and(2)Dingje and Dingri,all of which are situated southwest of *** of two genera and twelve species with six new species and they may be differen-tiated into two assemblages:the first assemblage of upper Oxfordian—lower Tithonianage with Belemnopsis gerardi(Oppel)as its leading species and the second of early Cre-taceous age with Hibolites subfusiformis(Raspail)as its chief *** geologic sections which bear the belemnites are given as follows(in descendingorder):

关键词： EARLY CRETACEOUS BELEMNITES FROM SOUTHERN TIBET,CHINA late jurassic length 西藏南部

Micropalaeontological and Geochemical Evidence of the late jurassic Radiolarians Cherts of Naga Ophiolite Hill, Nagaland, Northeast-India

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Open Journal of Geology 2021年第8期11卷 356-372页

作者： Ramamoorthy Ayyamperumal Ramasamy Sooriamuthu Gnanachandrasamy Gopalakrishnan Ganga Biswa Rajkumar Perumal Prerna Gahlaut Nusrat Nazir Justine Kandathil Antony MOE Key Laboratory of Western China’s Environmental System College of Earth and Environmental Sciences Lanzhou University Lanzhou China Department of Geology University of Madras Chennai India School of Geography and Planning Sun Yat-sen University Guangzhou China Department of Geology Mohanlal Sukhadia University Udaipur India Centre for Earth Sciences Indian Institute of Science Bangalore India Department of Geology Hemwati Nandan Bahuguna Garhwal University Srinagar India School of Earth Sciences Lanzhou University Lanzhou China Department of Earth Sciences Annamalai University Chidambaram India

We analyzed the radiolarian assemblages (pelagic sediments) and geochemical studies of 15 samples collected from Meluri district Nagaland, Naga Hills Ophiolite belt (NHO) and it consists of the Flysch Naga-Arakan-Yoma trough beyond the Indo-Myanmar border. It reflects one of the many components of the Himalayan Orogenic systems of Tethyan oceanic crust discovered in Nagaland at Meluri district of India and they have very well-preserved studies and can be identified to Upper jurassic (Kimmeridgian-mid-Tithonian). As well as a continuous sequence of Kimmeridgian-mid-Tithonian, five radiolarian assemblages have been identified in this study. This is so far the first recovery of pelagic sediment assemblages (Radiolarians) from the Naga Hills Ophiolite complex. Samples of Naga Hills Ophiolite belts fell in the Sublitharenite, Litharenite, and Fe-shale Fe-sand area, and the A-CN-K diagram indicates that these sediments in the source region were exposed deep to moderate weathering conditions. In the discriminant plot, the Naga Hill-Ophiolite-Chert samples occupy the field of origin of the sediment quartzose, and the log (K2O/Na2O) versus SiO2 samples fall into the active continental marginal field, and only one sample falls into an island arch, suggesting that the tectonic framework of the Naga Hills-Chert samples was deposited in the active continental margin and the diagrams K2O/Al2O3 and MgO/Al2O3 illustrated the tectonic setting of the marine environment from Naga Hill Ophiolite Chert. Such findings have been consistent with the current geology of Naga Hills in the province of Nagaland.

关键词： Geochemistry late jurassic Radiolarians Naga Hill Ophiloite Northeast Nagaland India