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Genesis and tectonic setting of Early Jurassic granitic rocks in Huashan Town,Xingcheng,western Liaoning
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作者 ZHAO Junfeng LI Weimin +1 位作者 LIU Tongjun GAO Jinhui 《Global Geology》 2024年第1期1-19,共19页
There are a large number of Mesozoic intrusive and volcanic rocks in western Liaoning of China,which is an ideal place to study the Mesozoic Paleo-Pacific subduction processes,and lithospheric destruc-tion of North Ch... There are a large number of Mesozoic intrusive and volcanic rocks in western Liaoning of China,which is an ideal place to study the Mesozoic Paleo-Pacific subduction processes,and lithospheric destruc-tion of North China Craton.Detailed petrographic,zircon U-Pb dating and geochemical studies of the Early Jurassic granites in Huashan pluton,Xingcheng,western Liaoning,indicate that the Early Jurassic granites were formed at 184-174 Ma,mainly composed of syenite and monzogranite.The geochemical characteristics show high contents of SiO_(2),Al_(2)O_(3)and Na_(2)O+K_(2)O,low contents of Fe_(2)O_(3)and MgO,enrichment in LREEs and LILEs,and depletion in HREEs and HFSEs,and have a high content of Sr and low contents of Y and Yb,with weak negative Eu anomalies and slightly negative anomalies of Ce,indicating that they are a set of intermediate-acidic adakitic granites in high-K calc-alkaline series.All the facts significantly suggest that the Early Jurassic adakitic granites were formed at the active continental margin in the context of Paleo-Pacific plate subduction. 展开更多
关键词 geochemistry PETROLOGY ADAKITE North China Craton western liaoning
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Survey and Countermeasures on Current Status of Farmer Training and Education Informatization in Western Liaoning Province
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作者 Zeguo DENG Jianwei LIU 《Asian Agricultural Research》 2023年第1期50-57,共8页
This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current st... This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current status of agricultural development in western Liaoning and farmers’needs for education and training and rural education informatization were surveyed.The construction of an education and technical support service platform for scientific and technological farmers in western Liaoning was proposed,aiming to use information technology to train modern professional farmers.Through independent and self-learning education and training methods,it is expected to promote great improvement in the scientific and technological quality and moral level of farmers in western Liaoning and cultivate professional farmers who are educated and understand both agricultural techniques and business management. 展开更多
关键词 western liaoning Province Professional farmers Education informatization TRAINING
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A New Troodontid (Theropoda: Troodontidae) from the Lower Cretaceous Yixian Formation of Western Liaoning, China 被引量:15
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作者 XUXing WANGXiaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期22-26,共5页
A specimen collected from the Lower Cretaceous Yixian Formation of western Liaoning, China, represents a new genus and species of troodontid theropod. The new taxon is named and described on the basis of the holotype ... A specimen collected from the Lower Cretaceous Yixian Formation of western Liaoning, China, represents a new genus and species of troodontid theropod. The new taxon is named and described on the basis of the holotype and the only known specimen, which comprises an articulated skeleton with the presacral vertebral, shoulder girdle and forelimbs missing as preserved. Diagnostic features of the new species include nasals that are sinusoid in lateral view, absence of a passage connecting the antorbital and maxillary fenestrae, relatively large teeth, plate-like chevrons forming a band along most of the length of the tail, and a long neck between the femoral head and shaft. The temporal constraints of the three paravian groups (Troodontidae, Dromaeosauridae and Aves) combined with the character distributions among the earliest known troodontids indicate a rapid evolution at the base of the Troodontidae. 展开更多
关键词 Early Cretaceous Yixian Formation Troodontidae western liaoning China
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Dongbeititan dongi,the First Sauropod Dinosaur from the Lower Cretaceous Jehol Group of Western Liaoning Province,China 被引量:10
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作者 WANG Xuri YOU Hailu +3 位作者 MENG Qingjin GAO Chunling CHENG Xiaodong LIU Jinyuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第6期911-916,共6页
We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it pos... We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it possesses, including the camellate internal structure of its presacral elements, the existence of pneumatocoels on the proximal ends of the dorsal ribs, and especially the medially deflected proximal portion of the femur, definitively establish the titanosauriform affinities of the specimen. It differs from other titanosauriforms in having a craniocaudally elongate coracoid with a squared cranioventral extreme and a long, smooth, and slightly convex acetabular edge of the pubis. It represents a new taxon, Dongbeititan dongi gen. et sp. nov. Comparative studies suggest that Dongbeititan is a basal titanosauriform, more derived than Euhelopus, Fusuisaurus, and Huanghetitan, but less derived than Gobititan and Jiutaisaurus. Dongbeititan represents the first sauropod dinosaur reported from the Lower Cretaceous Jehol Group of western Liaoning Province. 展开更多
关键词 DINOSAURIA SAUROPODA TITANOSAURIFORMES Jehol Group Yixian Formation Lower Cretaceous Beipiao western liaoning Province China
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A New Darwinopterid Pterosaur from the Middle Jurassic of Western Liaoning,Northeastern China and its Ecological Implications 被引量:13
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作者 Lu Junchang XU Li +1 位作者 CHANG Huali ZHANG Xingliao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第3期507-514,共8页
A new species of Darwinopterus,D.robustodens sp.nov.is described and named.Based on the new specimen,the diagnostic characters of Darwinopterus are amended and include:rostral dentition composed of well-spaced,spike-... A new species of Darwinopterus,D.robustodens sp.nov.is described and named.Based on the new specimen,the diagnostic characters of Darwinopterus are amended and include:rostral dentition composed of well-spaced,spike-like teeth;the longest teeth are confined to the anterior half of the tooth row;tooth alveoli have raised margins;nasoantorbital fenestra confluent;inclined quadrate;elongate cervical vertebrae with low neural spine and reduced or absent ribs;long tail of more than 20 caudals partially enclosed by filiform extensions of the pre-and postzygapophyses;short metacarpus less than 60 per cent length of humerus,fifth toe with two elongate phalanges and curved second pedal phalanx of the fifth toe with the angle between the proximal and distal segments about 130 degrees.The complete specimen of the new pterosaur D.robustodens sp.nov.provides much more osteological information.The differences in tooth morphologies between Darwinopterus modularis and D.robustodens sp.nov.suggest that they filled different ecological niches.The hard integument-bearing Coleoptera may have been the main food source of Darwinopterus robustodens. 展开更多
关键词 Darwinopterus robustodens Tiaojinshan Formation Middle Jurassic western liaoning China
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Precious Fossil-Bearing Beds of the Lower Cretaceous Jiufotang Formation in Western Liaoning Province, China 被引量:9
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作者 ZHANG Lijun YANG Yajun ZHANG Lidong GUO Shengzhe WANG Wuli ZHENG Shaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第3期357-364,共8页
Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil birdand reptile-bearing beds of... Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil birdand reptile-bearing beds of the formation in the Dachengzi, Chaoyang, Dapingfang.Meileyingzi and Fuxin-Yixian basins. Among them, the precious fossil-bearing beds in the Dachengzi Basin may be recognized as the Xidagou Bed of the second member and the Yangcaogoudonggou Bed of the third member; those in the Chaoyang Basin may be confirmed as the Shangheshou Bed of the second member and the Dongpochi Bed of the third member; those in the Dapingfang-Meileyingzi Basin are as the Lamagou Bed of the second member, the Huanghuagou Bed of the lower third member and the Yuanjiawa Bed of the upper third member; and those in the Fuxin-Yixian Basin are listed as the Tuanshanzi Bed of the second member and the Pijiagou Bed of the third member. Since these basins are distinctly separated and the bird and reptile fossils are mostly new genera and species, we have to use the associated fossil ostracod assemblages as index to correlate the Xidagou Bed with the Shangheshou Bed and the Lamagou Bed, and to correlate the Yuanjiawa Bed with the Yangcaogoudonggou Bed and the Pijiagou Bed. Primarily, we established the sequence of the precious fossil-bearing beds of the Jiufotang Formation in western Liaoning. They are represented by, in ascending order, the Xidagou Bed of the second member, the Huanghuagou Bed of the lower third member, and the Yuanjiawa Bed of the upper third member. Obviously, this work has significance for the study on the time-space distribution and radiation of birds and dinosaurs during the period of the middle Early Cretaceous. 展开更多
关键词 DIVISION correlation precious fossil-bearing beds Lower Cretaceous JiufotangFormation western liaoning
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An Early Cretaceous Avialian Bird, Shenzhouraptor sinensis from Western Liaoning, China 被引量:8
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作者 Ji Qiang, Ji Shu’an, You Hailu, Zhang Jianping,Zhang Hongbin, Zhang Nanjun, Yuan Chongxi and Ji XinxinDepartment of Earth Sciences, Nanjing University, Nanjing, Jiangsu 100093Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037 School of Earth and Space Sciences, Peking University, Beijing 100871China University of Geosciences, Beijing 100083 China Dinosaur Park of Changzhou, Changzhou, Jiangsu 213002 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第1期21-27,共7页
This paper describes an avialian bird from the Early Cretaceous JiufotangFormation in Yixian county, western Liaoning China, which is named as Shenzhouraptor sinensis by Jiet al. on July 15, 2002. Shenzhouraptor sinen... This paper describes an avialian bird from the Early Cretaceous JiufotangFormation in Yixian county, western Liaoning China, which is named as Shenzhouraptor sinensis by Jiet al. on July 15, 2002. Shenzhouraptor sinensis is characterized by no teeth in its mouth, theforelimbs longer than the hindlimbs, a long tail with more than 23 caudal vertebrae, U-shapedwishbone, and remiges longer than the total length of ulna and manus. It is certain that the newavialian bird is really capable of powerful flight, representing a missing link between theropoddinosaurs and birds. 展开更多
关键词 Avialian birds Early Cretaceous Jiufotang Formation western liaoning China
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An Adult Specimen of Hongshanosaurus houi (Dinosauria:Psittacosauridae) from the Lower Cretaceous of Western Liaoning Province, China 被引量:6
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作者 YOUHailu XUXing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第2期168-173,共6页
A new specimen consisting of a complete skull and lower jaw was discovered from the Lujiatun bed of the Lower Cretaceous Yixian Formation in the Lujiatun site, Beipiao, western Liaoning Province. It represents an adul... A new specimen consisting of a complete skull and lower jaw was discovered from the Lujiatun bed of the Lower Cretaceous Yixian Formation in the Lujiatun site, Beipiao, western Liaoning Province. It represents an adult specimen of Hongshanosaurus houi. Comparative studies show that Hongshanosaurus is distinguishable from its sister taxon Psittacosaurus by having the preorbital portion about half of the basal skull length, and the elliptical external naris, orbit, and a lower temporal fenestra oriented caudodorsally. 展开更多
关键词 DINOSAURIA Psittacosauridae Hongshanosaurus ONTOGENY Lower Cretaceous western liaoning
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New Eoenantiornithid Bird from the Early Cretaceous Jiufotang Formation of Western Liaoning, China 被引量:8
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作者 LI Li DUAN Ye +3 位作者 HU Dongyu WANG Li CHENG Shaoli HOU Lianhai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期38-41,共4页
Enantionithine birds are the most blooming branch of early birds and have distinct diversities. A large number of enantionithine birds have been reported from the Early Cretaceous Jiufotang Formation in western Liaoni... Enantionithine birds are the most blooming branch of early birds and have distinct diversities. A large number of enantionithine birds have been reported from the Early Cretaceous Jiufotang Formation in western Liaoning, China. Recently, we discovered a new eoenantiornithid bird from the Jiufotang Formation in Dapingfang Town, western Liaoning. A new eoenantiornithid bird, Dapingfangornis sentisorhinus gen. et sp. nov., is erected based on this complete skeleton with a skull. The new bird is distinguished from other known Mesozoic birds in a medium to small size, a distinct thorn-like process on the nasals, a sternum with a long and a short lateral processes. The thorn-like process on the nasal has not been discovered among known fossil birds, thus the discovery also provides new materials on the diversities of early birds. 展开更多
关键词 Eoenantiornithid Dapingfangornis sentisorhinus Jiufotang Formation Early Cretaceous western liaoning
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Largest Toothed Pterosaur Skull from the Early Cretaceous Yixian Formation of Western Liaoning, China, with Comments on the Family Boreopteridae 被引量:6
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作者 LU Junchang PU Hanyong +2 位作者 XU Li WU Yanhua WEI Xuefang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期287-293,共7页
A new pterosaur Moganopterus zhuiana gen. et sp. nov. is erected based on a complete skull with lower jaws and anterior cervical vertebrae. It is characterized by much elongated upper and lower jaws with at least 62 t... A new pterosaur Moganopterus zhuiana gen. et sp. nov. is erected based on a complete skull with lower jaws and anterior cervical vertebrae. It is characterized by much elongated upper and lower jaws with at least 62 total, long, curved teeth with sharp tips, a well developed parietal crest extending posterodorsally, forming an angle of 15 degrees with the ventral margin of the skull, the ratio of length to width of cervical vertebrae greater than 5:1. The skull length is 750 mm, and it is the largest toothed pterosaur found so far in the world. Based on this new pterosaur, the Boreopteridae can be divided into two subgroups: Boreopterinae sub-fam, nov. and Moganopterinae sub-fam, nov., which is also confirmed by the phylogenetic analysis. 展开更多
关键词 Moganopterus Boreopteridae Yixian Formation western liaoning
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A Possible Long-tailed Bird with a Pygostyle from the Late Mesozoic Yixian Formation, Western Liaoning, China 被引量:3
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作者 L Junchang1 and HOU Lianhai2 1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037 2 Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044 Department of Biology, Capital Normal University, Beijing 100037 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第1期7-10,共4页
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 fre... 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. 展开更多
关键词 western liaoning Yixian Formation late Mesozoic pygostyle
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A New Genus of Fossil Cycads Yixianophyllum gen. nov. from the Late Jurassic Yixian Formation, Western Liaoning, China 被引量:2
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作者 ZHENG Shaolin LI Nan +2 位作者 LI Yong ZHANG Wu BIAN Xiongfei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第5期582-592,共11页
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... 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. 展开更多
关键词 western liaoning Yixian Formation Late Jurassic CYCADS YixianophyUum gen. nov. epidermal structures
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Analysis on the Changes of Temperature and Heat Resources in Rural Area of Chaoyang in Western Liaoning 被引量:2
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作者 ZONG Ying-fei TAO Lin ZHANG Guo-lin 《Meteorological and Environmental Research》 CAS 2011年第2期50-52,共3页
[Objective] The aim was to study the change characteristics of temperature and heat resources in rural area of Chaoyang in western Liaoning. [Method] Based on the data from rural meteorological station in Chaoyang in ... [Objective] The aim was to study the change characteristics of temperature and heat resources in rural area of Chaoyang in western Liaoning. [Method] Based on the data from rural meteorological station in Chaoyang in western Liaoning from 1966 to 2010, the change characteristics of temperature and heat resources in rural area in Chaoyang were analyzed by means of serial correlation and climate tendency method, so as to master its climate situation. [Result] The annual average value of daily average temperature, daily maximum temperature and daily minimum temperature in rural area of Chaoyang in western Liaoning from 1966 to 2010 showed fluctuation variation, and the annual average value of daily maximum temperature increased most obviously with the climatic tendency of 0.328 ℃/10 a and highest significant level, so it played an important role in temperature increase, next came daily average temperature (0.151 ℃/10 a), while there was no obvious decrease in daily minimum temperature. The average of daily maximum temperature in winter half year increased more obviously than that in summer half year, with the climatic tendency of 0.417 and 0.250 ℃/10 a, respectively; the trend of daily average temperature reached low significant level, and there was no obvious variation in daily minimum temperature. In addition, ≥10 ℃ accumulated temperature in rural area of Chaoyang in western Liaoning went up obviously, with the climatic tendency of 42.59 ℃·d/10 a, namely it increased by 192 ℃·d in recent 45 years. [Conclusion] The study could provide climatic reference for the adjustment of agriculture structure and varieties distribution. 展开更多
关键词 western liaoning Rural area TEMPERATURE Heat resources Trend variation China
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New Material of Pterosaur Sinopterus (Reptilia:Pterosauria) from the Early Cretaceous Jiufotang Formation,Western Liaoning,China 被引量:1
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作者 Lü Junchang LIU Jinyuan +3 位作者 WANG Xuri GAO Chunling MENG Qingjin JI Qiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期783-789,共7页
Based on a new nearly complete postcranial skeleton of an adult specimen of Sinopterus from the Early Cretaceous Jiufotang Formation of western Liaoning, China, the diagnosis of Sinopterus is amended. The revised diag... Based on a new nearly complete postcranial skeleton of an adult specimen of Sinopterus from the Early Cretaceous Jiufotang Formation of western Liaoning, China, the diagnosis of Sinopterus is amended. The revised diagnosis of Sinopterus includes skull relatively elongate with weakly developed cranial crest; ratio of the length of Ph2d4 to that of Ph1d4 is approximately 0.73; ratio of the length of wing metacarpal to that of metatarsal 3 is 4.5; ratio of the length of mt3 to that of tibia is approximately 0.21, and wing phalanges 1 and 2 are straight. Comparison between the ratios of the limb bones between non-adult and adult individuals of Sinopterus indicates that during the ontogenetic process, some ratios between bones are constant, such as the first wing phalanx to the second wing phalanx, the wing metacarpal to the metatarsal 3, metatarsal 3 to the tibia, but others are not, such as humerus to wing metacarpal and femur to tibia, in which the former grows faster than the latter. 展开更多
关键词 Sinopterus amended diagnosis ONTOGENY Jiufotang Formation Early Cretaceous western liaoning China
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New Fossil Liverworts from the Lower Cretaceous of Western Liaoning, China 被引量:1
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作者 GUO Caiqing YAO Jianxin +2 位作者 ZHANG Jianwei WU Pengcheng LI Chengsen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第5期1542-1552,共11页
Sixteen liverwort specimens collected from the Lower Cretaceous Yixian Formation of Huangbanjigou Village, Liaoning Province, China are studied in this work. The plants are thalloid and preserved in brown arenaceous m... Sixteen liverwort specimens collected from the Lower Cretaceous Yixian Formation of Huangbanjigou Village, Liaoning Province, China are studied in this work. The plants are thalloid and preserved in brown arenaceous mudstone as impressions. Based on examinations, the liverworts are assigned to two new genera and five new species: Riccardiothallus palmata sp. nov., Pallaviciniites stricta sp. nov., Pellites latithallus gen. et sp. nov., Conocephalumites hexagonites gen. et sp. nov. and Metzgerites multifidus sp. nov., belonging to five families and five genera. The fossil research indicates that the divergence of families, Aneuraceae and Metzgeriaceae, Pallaviciniaceae and Hymenophytaceae,Pelliaceae and Fossombroniaceae, was in the Lower Cretaceous(125 Ma). The research provides significant additions to the fossil liverwort records in Western Liaoning and offers fossil evidence for studying the classification and evolution of extant liverworts. 展开更多
关键词 LIVERWORTS Early Cretaceous CLASSIFICATION DIFFERENTIATION western liaoning China
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A New Female Cone,Araucaria beipoiaoensis sp.nov.from the Middle Jurassic Tiaojishan Formation,Beipiao,Western Liaoning,China and Its Evolutionary Significance 被引量:1
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作者 ZHENG Shaolin ZHANG Lidong ZHANG Wu YANG Yaiun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第2期266-282,共17页
A new species of Araucaria, Araucaria beipiaoensis sp. nov., collected from the Middle Jurassic Tiaojishan Formation, southern hill of Shebudai village, near Beipiao city, western Liaoning is based on a permineralized... A new species of Araucaria, Araucaria beipiaoensis sp. nov., collected from the Middle Jurassic Tiaojishan Formation, southern hill of Shebudai village, near Beipiao city, western Liaoning is based on a permineralized female cone, which is ovate to elliptical in shape, about 11 cm × 7 cm × 4.5 cm in size. The cone bears rhomboid bracts that are spirally attached, texture thicker, with wings on both sides, with a detached lamina-like apex at the tip. In inner structure the ovuliferous scales are thicker and fused with bracts at the end with a ligular sulcns. There is one wingless ovule/seed per seed-scale complex embedded in the ovuliferous scale tissue, with the micropyle directed toward the cone axis. The ovules/seeds are long ovate or elliptical in shape, 1 cm long and near the base about 3 mm in diameter; the ovule/seed integuments have begun differentiation into 3 layers: the sarcotesta, sclerotesta, and endotesta. The nucellus is free from the enclosing integuments except in the chalazal region where it is fused to the inner layer (endotesta) of integument. Some ovules show cellularized nucellar tissue. Mature seeds exhibit the papery-thin wavy nucellus characteristically near to the micropyle. The embryonic tissue appears to be four cotyledons. The morphology and structure of the cone shows a close relationship to the araucarian cones of fossil and living genera but differs from any known species. The new species is distributed in the Middle Jurassic of the northern hemisphere, especially Asia, and has important significance for the evolution of the Family Araucariaceae. 展开更多
关键词 ARAUCARIA female cone Middle Jurassic Tiaojishan Formation western liaoning
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Geochronology and Petrogenesis of Mesozoic Granitoids in the Geological Corridor of Western Liaoning Province, China 被引量:1
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作者 XU Xuechun ZHENG Changqing CUI Fanghua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期46-48,共3页
The geological corridor of Western Liaoning province is an area of length 100 km and width 20 km and located in the eastern segment of northern margin of North China Craton(NCC),with the wide distribution of Mesozoi... The geological corridor of Western Liaoning province is an area of length 100 km and width 20 km and located in the eastern segment of northern margin of North China Craton(NCC),with the wide distribution of Mesozoic granitic magmatism.It is the ideal area to study the granitic petrogenesis,the nature of magma source and the tectonic attribute.In this paper,we do the systematic researchesaboutthepetrology,geochronology,geochemistry and Zircon Hf isotopic of granitic rocks.Based on the mentioned above,we have built the geochronological framework and have discussed the petrogenesis,the nature of magma source and the tectonic setting of granitic rocks.And according to the information about the crust-mantle interaction recorded in granitic rocks and the regional data,we also discuss the relationship between Mesozoic granitic magma activities and lithosphere thinning,destruction of Craton mechanism in the eastern segment of northern margin of NCC.The Mesozoic granitic magma activities in The geological corridor of Western Liaoning province are divided into four stages(Fig.1):Late Triassic(230 Ma;28 Ma),early-middle Jurassic(194 Ma;69 Ma),Late Jurassic(161 Ma;55 Ma)and Early Cretaceous(139Ma;21 Ma).The late Triassic granitic rocks are composed of adamellite,monzogranite and diorite.The samples have high Sr,Cr,Ni content and low Yb,Y content,and the sample have high Mg#and high ratio of Sr/Y and La/Yb.The characteristics of inhomogenous negative value ofεHf(t)(-6.40;0.19)in magmatic zircons and ancient crustal TDM2 values of 1.25 Ga;.67 Ga(Fig.2),indicate that the Triassic granitic rocks were formed in a post-collisional extensional tectonic setting aftersubduction of Paleo-Asian Ocean and the subduction of Yangtze Craton,and they are the product of partial melting of ancient lower crust under the condition of the mantle-derived magma underplating,and geochemical features of the high Sr and low Y are inherited from the source of magma which is also enriched in Sr and depleted in Y.The geochemical features and assemblages of rocks formed during Jurassic-early Cretaceous are similar.The early-middle Jurassic granitic rocks are composed of syenogranite,monzogranite,quartz monzonite,granitic porphyry,granodiorite and quartz diorite.The late Jurassic granitic rocks are composed of monzogranite,granitic porphyry,and quartz diorite.The early Cretaceous granitic rocks are composed of monzogranite,quartz syenite,granitic porphyry,and quartz monzodiorite.The samples are characterized by the high SiO;content and total alkalis and are belonged to the high-K calc-alkaline series.And the characteristics of quasi-aluminous to weakly peraluminous(A/CNK<1.1,A/NK>1.0)and the negative relationship between P;O;and SiO;are similar to the characteristics of I-type granite.The samples are enriched in LREE contents and K,Pb and depleted in Nb,Ta,Ti and P.The characteristics of assemblage and geochemical features indicate the Jurassic-Cretaceous granitic rocks formed in the setting of active continental margin related to the subduction.The magmatic zircons of early-middle Jurassic granitic rocks have negativeεHf(t)(-16.60;4.15)and ancient crustal TDM2 values of 1.49 Ga;.28 Ga which indicates the primary magma is from the partial melting of ancient middle-lower crust(Fig.2).These rocks formed in the setting of active continental margin of subduction of Paleo-Pacific plate.The magma source of granitic rocks is from partial melting of the ancient lower-middle curst caused by the underplating of mantle magma,which formed in the condition of fluid derived from the dehydration of subducted slab affected on the lithosphere mantle.The magmatic zircons of late Jurassic granitic rocks have negativeεHf(t)(-26.24;18.56)and ancient crustal TDM2 values of(2.39 Ga;.87 Ga)which indicates the primary magma is from the partial melting of ancient upper-middle crust(Fig.2).And these rocks may be formed in the setting of active continental margin of intense subduction of Paleo-Pacific plate.In the intense subduction,the mantle magma is formed in the interaction of fluid derived from the dehydration of subducted slab with the lithosphere mantle,then further underplated the ancient middle-upper crust and make the ancient middle-upper curst partial melting.In this setting,the late Jurassic rocks are distributed widely in eastern North China.The samples in early Cretaceous have a wide range of values of Hf isotope:-24.92;20.88(139 Ma),-4.72;6.22(130 Ma),-17.30;11.56(125 Ma;21 Ma),and the characteristics of Hf isotope indicate the source of earlyCretaceousmagma(middle-uppercrust,middle-lower crust or juvenile crust)is very complicated(Fig.2).The early Cretaceous granitic rocks were formed in the lithosphere extensional environment when the Paleo-Pacific plate subducted/roll-backed quickly in the direction of NNW with high angle.The regional extension made the asthenosphere upwell and be unstable,and the magma of mantle was formed.Then wide mantle-crust interactions make the crust partial melt,as a result,the source of early Cretaceous igneous rocks which are distributed widely in eastern North China Craton.The participation of depleted mantle components in the process of Late Triassic rock formation in western Liaoning area indicate the time of the lithosphere thinning in the eastern segment of northern margin of NCC begin from the late Triassic(;30 Ma).The double subduction of Paleo-Asian Ocean and Yangtze Craton in the early period is the reason of the lithosphere thinning.After the double subduction,the mantle-derived magma upwell and underplate the lithosphere mantle and lower crust in a post-collisional extensional tectonic setting.As a result,the lithosphere began to thin but the Craton destruction was not obviously in this period.The participation of depleted mantle components makes the continental crust slightly reforms and grows.The eastern segment of northern margin of NCC was in the setting of active continental margin in Jurassic,and the continuing dehydration and metasomatism of subduction slab changed the physical and chemical properties of the lithosphere mantle.The initial weak subduction in early-middle Jurassic makes the lithosphere become thin but no obvious destruction of Craton.And in this period,the continental crust reformed and grew slightly.As the subduction became stronger during late Jurassic,the thickness of lithosphere in eastern segment of northern margin of NCC become thinner and the destruction of Craton occurred locally and the continental crust reformed and grew to some extent.In early Cretaceous,the change of direction and angle of subduction of Paleo-Pacific led to the regional extension,which is the reason for massive mantle material upwelling and intense crust-mantle interaction.And the lithosphere thinning and destruction of Craton reached the peak.As a result,the effects of reconstruction and hyperplasia of continental crust are obviously.In our opinions,the underplating mechanism of mantle-derived magma occurred mainly in the initial stage(early Mesozoic)oflithosphere thinning,and the delamination of lithosphere mantle or lower crust coexisted while erosion action of mantle material occurred in the stage(late Mesozoic)of strong lithosphere thinning and destruction of Craton. 展开更多
关键词 Geochronology and Petrogenesis of Mesozoic Granitoids in the Geological Corridor of western liaoning Province rock TDM As Pb China
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A New Species of Huaxiapterus (Pterosauria:Tapejaridae) from the Early Cretaceous of Western Liaoning,China 被引量:1
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作者 LU Junchang GAO Yubo +2 位作者 XING Lida LI Zhixin JI Qiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第5期683-687,共5页
A new species of Huaxiapterus: H. benxiensis sp. nov. is erected based on the new specimen. The diagnostic characters of Huaxiapterus benxiensis are well-developed premaxillary crest and parietal spine, the crest and... A new species of Huaxiapterus: H. benxiensis sp. nov. is erected based on the new specimen. The diagnostic characters of Huaxiapterus benxiensis are well-developed premaxillary crest and parietal spine, the crest and spine parallel and extending posterodorsally, and a shallow groove present on the dorsal surface of the anterior portion of the mandibular symphysis. The different skull morphologies of Chinese tapejarid pterosaurs indicate that they are much more diverse than the previous thought. 展开更多
关键词 Huaxiapterus benxiensis Chinese tapejarid pterosaurs Early Cretaceous western liaoning
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A reassessment of Iteravis huchzermeyeri and Gansus zheni from the Jehol Biota in western Liaoning, China 被引量:1
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作者 Shu-bin Ju Xu-ri Wang +1 位作者 Yi-chuan Liu Yang Wang 《China Geology》 2021年第2期197-204,共8页
The authors reassessed the taxonomic distinction of Iteravis huchzermeyeri and Gansus zheni,which are two species of Ornithuromorpha based on specimens from the same locality in western Liaoning and derive from the Je... The authors reassessed the taxonomic distinction of Iteravis huchzermeyeri and Gansus zheni,which are two species of Ornithuromorpha based on specimens from the same locality in western Liaoning and derive from the Jehol Biota.The detailed comparisons of the holotype and referred specimens of both species,reveal no anatomical features that distinguish these taxa as separate species.Some minor differences are considered to relate to ontogenetic or interspecific differences.The stratigraphic occurrence for both specimens is the Lower Cretaceous Jiufotang Formation.Accordingly,the authors conclude that Iteravis huchzermeyeri has priority,by 15 days,for this taxon and that Gansus zheni is a junior synonym.The diagnosis of Iteravis huchzermeyeri is revised based on further study on all specimens referred to this species.Its generic distinction from Gansus is maintained thereby removing a potential genus-level correlation linking Xiagou Formation in Gansu Province with the Jiufotang Formation in Liaoning Province. 展开更多
关键词 Jehol Biota Lower Cretaceous Ornithuromorpha SYNONYM Geological survey engineering western liaoning China
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New Material of Feilongus(Reptilia: Pterosauria) from the Lower Cretaceous Jiufotang Formation of Western Liaoning 被引量:1
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作者 WANG Xuri SHEN Caizhi +1 位作者 GAO Chunling JIN Kemo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第1期13-17,共5页
Based on a new nearly naturally preserved skull and four cervical vertebrae of the pterosaur Feilongus sp. from the lower Cretaceous Jiufotang Formation of Beipiao, western Liaoning province, northeastern China, the d... Based on a new nearly naturally preserved skull and four cervical vertebrae of the pterosaur Feilongus sp. from the lower Cretaceous Jiufotang Formation of Beipiao, western Liaoning province, northeastern China, the diagnosis of Feilongus is amended. The revised diagnosis notes long, curved, needle-shaped teeth that are confined to the jaw far anterior to the nasoantorbital fenestra; posterior teeth that are slightly smaller than the anterior teeth; cervical vertebrae elongated with a ratio of length to width greater than 5; tooth number of about 78; and two cranial sagittal crests. 展开更多
关键词 pterosaur amended diagnosis Jiufotang Formation Aptian western liaoning
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