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Late Silurian to Early Devonian Palynomorphs from Qujing,Yunnan,Southwest China 被引量:13
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作者 TIAN Jiajie ZHU Huaicheng +1 位作者 HUANG Min LIU Feng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第3期559-568,共10页
Well-preserved and diversified spores,cryptospores,and acritarchs have been recorded from a relatively continuous sequence that encompasses the Silurian-Devonian boundary in Qujing, Yunnan,southwest China.Four spore a... Well-preserved and diversified spores,cryptospores,and acritarchs have been recorded from a relatively continuous sequence that encompasses the Silurian-Devonian boundary in Qujing, Yunnan,southwest China.Four spore assemblage zones from Late Silurian to Early Devonian in age are proposed based on the first appearance datum(FAD)of characteristic spore species.In ascending stratigraphic order,they are Ambitisporites dilutus-Apiculiretusispora synorea(DS;Late Ludfordian to Early Pridoli),Synorisporites verrucatus-Apiculiretusispora plicata(VP;Pridoli),Apiculiretusispora minuta-Leiotriletes ornatus(MO;Lochkovian),and Verrucosisporites polygonalis-Dibolisporites wetteldorfensis(PW;Pragian).The acritarch assemblage from the upper part of the Yulongsi Formation,the Xiaxishancun Formation,and the lower-middle parts of the Xitun Formation indicates an age of Late Silurian.Based on palynological evidence,the upper part of the Yulongsi Formation is considered Late Ludfordian to Early Pridoli in age;the Xiaxishancun Formation is believed to be Pridoli in age;the Xitun Formation is considered Late Pridoli to Early Lochkovian in age;the Guijiatun Formation is considered Lochkovian in age;and the Xujiachong Formation is Late Lochkovian to Pragian in age.The Silurian-Devonian boundary is recognized between the VP and the MO spore biozones,and occurs within the middle part of the Xitun Formation. 展开更多
关键词 SPORE cryptospore ACRITARCH SILURIAN DEVONIAN qujing southwest china
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Reanalysis on the Spectral Characteristics and Materials of Jade Jue Unearthed from Lijiashan Ancient Tomb in Yunnan Province, China
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作者 Ting Fang Jifu Liu Mingxing Yang 《宝石和宝石学杂志(中英文)》 CAS 2024年第2期48-55,共8页
Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analy... Jade ware Jue is one of the most fashionable ornament in ancient China from the Neolithic Age to the Han Dynasty.In this study,the remnants of jade ware Jue,from Lijiashan ancient tomb group have been tested and analyzed respectively.The samples through a light etch surface showing glass luster and those with a severe etch surface showing earthen luster.With the aid of X-ray fluorescence Spectrometer(X-ray Fluorescence)test and X-ray diffraction(XRD)detection,the results show that tremolite is not the main mineral of the sample.The main components of the tested samples with light erosion are antigorite and talc,although the main components of the samples with severe erosion are calcite containing calcium carbonate barium.Furthermore,the research on jade ware Jue in Yunnan culture has not only contributed to our further understanding of the jade objects from Yunnan culture and the variety of jade material located in the Yunnan Province.It also provides a basis for the trace of the history and culture through the distribution and evolution of burial hierarchy laws.At the same time,the microscopic observation of the tested samples manifested a residual trace of“string”at the perforation,which has played a critical role in restoring the wearing of jade ware Jue from the tombs of the ancient Yunnan State and the handicraft skills at that time. 展开更多
关键词 Dian culture jade Jue corroded ancient jade XRD erosion mechanism yunnan china
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New and interesting diatoms from the Shimen Wetwalls,Yunnan Province,China.Ⅱ.The diatom genus Nupela Vyverman&Compère(Bacillariophyceae)
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作者 Qi LIU Xi LUO +1 位作者 Shulian XIE John Patrick KOCIOLEK 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期327-341,共15页
We detailed the valve morphology of five new species of diatom genus Nupela from wetwall communities in Yunnan Province,China,with light and scanning electron microscope.The five new species demonstrate great variabil... We detailed the valve morphology of five new species of diatom genus Nupela from wetwall communities in Yunnan Province,China,with light and scanning electron microscope.The five new species demonstrate great variability within the genus,as three of them are biraphid and two are monoraphid.In addition,variation was noted in the structure of internal proximal raphe ends,with some species having anchor-shaped ends and other species have hooked ends.The genus Nupela has grown considerably in 30years since it was first proposed,going from a monotypic genus to over 85 taxa.Diagnosis of the genus is based on the presence of an external covering over the areolae.We discussed the systematic placement of Nupela within the naviculoid diatoms.Yunnan Province appears to harbor many endemic diatom taxa,and many regions of the province have yet to be studied. 展开更多
关键词 Nupela scanning electron microscope(SEM) yunnan new species morphology china BACILLARIOPHYCEAE
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Inferring Human-elephant Coexistence Based on Characteristics of Human-elephant Interactions in Nangunhe of Yunnan,China
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作者 WANG Jiahui CHEN Ying +2 位作者 SUN Yakuan LYU Zhuoluo SHI Kun 《Chinese Geographical Science》 SCIE CSCD 2023年第2期363-376,共14页
Human-wildlife conflict(HWC)negatively impacts both humans and wildlife.Attitudes of local residents have been critical in promoting wildlife conservation.It is therefore necessary to understand the characteristics of... Human-wildlife conflict(HWC)negatively impacts both humans and wildlife.Attitudes of local residents have been critical in promoting wildlife conservation.It is therefore necessary to understand the characteristics of HWC and identify influential factors on attitudes towards conservation to implement conservation strategies efficiently.This research focused on features of human-elephant interactions,while attitudes and values regarding the small population of Asian elephants(Elephas maximus)in Nangunhe National Nature Reserve(NNR),Yunnan,China.The total of 327 valid questionnaires were gathered around the area where Asian elephants were distributed.Logistic regression models were employed to analyze the correlations among five predictor variables(‘Area’,‘Family size’,‘Annual income’,‘Quantity of family members in non-primary industries’and‘Experiencing loss or not’)and three response variables(‘Attitude towards elephants’,‘Perception of the values of elephants’and‘Attitude towards tourism development’).The study area was densely forested with tea plants,rubber trees,corns and sugarcane.There,25.99%of respondents reported the experience of human-elephant conflict(HEC),with crop raiding and cash crop damages being the major conflict types.To demonstrate respect for elephants and to mitigate HEC,a unique custom called‘Giving tribute to elephants’was developed long ago.Respondents’township with an official annual festival of‘Giving Tribute to Elephants’(odds ratio(OR)=2.75,P=1.73×10^(-6))and higher annual income(OR=2.09,P=5.45×10^(-5))significantly contributed to forming a more positive attitude towards elephants,whereas HEC itself have contributed to a more negative attitude(OR=0.50,P=3.29×10^(-3)).Therefore,we propose that:1)reducing human-elephant conflict by testing multiple mitigation measures and adopting the most effective one of them;2)enhancing local livelihoods through the development of ecological products and ecotourism;and 3)preserving and developing the Wa culture in this region.The study area deserves more attention and further research to explore and obtain endorsement from the public to achieve coexistence between human and wildlife. 展开更多
关键词 Asian elephant(Elephas maximus) Wa people human-elephant conflict COEXISTENCE Nangunhe National Nature Reserve yunnan china
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Geological characterization and exploration potential of shale gas in the Carboniferous Jiusi Formation,northern Guizhou and Yunnan provinces,SW China
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作者 Weiming Feng Rong Li +3 位作者 Zhan Zhao Qian Yu Wei Liu Junfeng Cao 《Energy Geoscience》 2023年第3期169-181,共13页
Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential ... Dark mudstones and shales of the Carboniferous Jiusi Formation are widely developed in northern Guizhou and Yunnan provinces, SW China. However, the distribution, reservoir characterization, and exploration potential of organic-rich shales in this area are yet to be quantified, thus limiting the prospect of shale gas in this area. This study investigates the basic geological conditions of Jiusi shale gas, using core data, well-logs, and some other test data, obtaining the following results. The organic-rich shales are mainly composed of deltaic-to-shallow-shelf deposits, with thickness ranging from 0 to 450 m, and above 350 m around the subsidence center. The organic matter is mainly type Ⅱ kerogen with TOC content of mostly 1%–2%, indicating a moderate maturity. The argillaceous shale reservoirs are indicative of strong heterogeneity, high clay minerals content, low porosity, low permeability, high specific surface area, and relatively developed secondary porosity. The gas-log anomaly intervals obtained from the survey wells have a cumulative thickness that is apparently greater than 200 m, and a few shale intervals showing high desorbed and adsorbed gas contents. Due to complex structures in the study area, conditions responsible for shale gas occurrence and trapping are generally moderate. However, areas having wide and gentle folds with moderate depth of burial reveals relatively favorable conditions of hydrocarbon traps. In contrast with typical marine-continental transitional shales, the Jiusi shale have better geological conditions for shale gas preservation. The analysis of the geological framework and hydrocarbon potential of Carboniferous Jiusi Formation provide more insight for the exploration of Carboniferous shale gas in southern China. 展开更多
关键词 Marine-continental tansitional fades 0rganic-nich shale Shale gas Exploration potential CARBONIFEROUS Northem border area between Guizhou and yunnan china
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A New Species of the Genus Alulatettix Liang (Orthoptera: Tetrigoidea: Tetrigidae) from Yunnan, China 被引量:2
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作者 邓维安 王延峰 +1 位作者 郑哲民 韦仕珍 《Entomotaxonomia》 CSCD 北大核心 2009年第4期259-262,共4页
One new species of the genus Alulatettix Liang, Alulatettix ochrotibis Deng and Zheng, sp. nov. is described. Type specimens are deposited in the Institute of Zoology, Shaanxi Normal University, China.
关键词 ORTHOPTERA TETRIGOIDEA TETRIGIDAE Alulatettix new species yunnan china
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TWO NEW SPECIES AND ONE NEW COMBINATION OF THE CONIFER SAWFLY FAMILY DIPRIONIDAE (HYMENOPTERA: SYMPHYTA) FROM YUNNAN, CHINA 被引量:3
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作者 徐正会 《Zoological Research》 CAS CSCD 1997年第2期171-176,共6页
In this paper two new species of Diprionidae were described from Yunnan Province, China, Gilpinia hebedentata, sp. n. and Macrodiprion wui, sp. n. Another species recorded in Yunnan, Gilpinia disa Smith, was transferr... In this paper two new species of Diprionidae were described from Yunnan Province, China, Gilpinia hebedentata, sp. n. and Macrodiprion wui, sp. n. Another species recorded in Yunnan, Gilpinia disa Smith, was transferred from Gilpinia Benson to Microdiprion Enslin. Macrodiprion Enslin is a newly recorded genus in China. 展开更多
关键词 HYMENOPTERA Diprionidae New species New combination yunnan china
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THREE SPECIES OF COLLEMBOLA FROM YUNNAN,SOUTHWEST CHINA (Apteygota)* 被引量:1
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作者 田村浩志 赵立军 《Zoological Research》 CAS CSCD 1998年第2期153-159,共7页
Two new species and a known species of Collembola are described or redescribed from Yunnan Province,southwest China,Hypogastrura xiaoi sp. nov.,H. zhangi sp. nov. and Paranurophorus simplex Denis,1928, respectively. T... Two new species and a known species of Collembola are described or redescribed from Yunnan Province,southwest China,Hypogastrura xiaoi sp. nov.,H. zhangi sp. nov. and Paranurophorus simplex Denis,1928, respectively. The last species is the second record from China since 1928. 展开更多
关键词 New species Hypogastrura xiaoi H. zhangi Paranurophorus simplex yunnan china
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A New Vetulicolian from the Early Cambrian Chengjiang Fauna in Yunnan of China 被引量:13
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作者 CHENAilin FENGHongzhen +2 位作者 ZHUMaoyan MADongsheng LIMing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第3期281-287,共7页
The genus and species Yuyuanozoon magnificissimi gen. et sp. nov., a new fossil vetulicolian, is reported from the Early Cambrian Chengjiang Fauna in Yunnan of China. It has a bipartite body plan and five pairs of cha... The genus and species Yuyuanozoon magnificissimi gen. et sp. nov., a new fossil vetulicolian, is reported from the Early Cambrian Chengjiang Fauna in Yunnan of China. It has a bipartite body plan and five pairs of chain-formed gill sacs, showing the general characteristics of Ventulicolia. However, the exclusive 'atrial cavity' and external gill observed indicate that the new form is different from those previously described as vetulicolians, probably representing a lineage developed within deuterostomes and more primitive than urochordates. 展开更多
关键词 vetulicolian Chengjiang Fauna Early Cambrian Chengjiang yunnan china
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Fluid Inclusions of Calcite and Sources of Ore-forming Fluids in the Huize Zn-Pb-(Ag-Ge) District, Yunnan, China 被引量:25
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作者 HANRunsheng LILTCongqiang +5 位作者 HUANGZhilong MADeyun LIYuan HUBin MAGengsheng LEILi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期583-591,共9页
The Huize Zn-Pb- (Ag-Ge) district is a typical representative of the well-known medium-to large-sized carbonate-hosted Zn-Pb- (Ag-Ge) deposits, occurring in the Sichuan-Yunnan-Guizhou Pb-Zn Ore-forming Zone. Generally... The Huize Zn-Pb- (Ag-Ge) district is a typical representative of the well-known medium-to large-sized carbonate-hosted Zn-Pb- (Ag-Ge) deposits, occurring in the Sichuan-Yunnan-Guizhou Pb-Zn Ore-forming Zone. Generally, fluid inclusions within calcite, one of the major gangue minerals, are dominated by two kinds of small (1-10 um) inclusions including pure-liquid and liquid. The inclusions exist in concentrated groups along the crystal planes of the calcite. The ore-forming fluids containing Pb and Zn, which belong to the Na+-K+-Ca2+-Cl--F--SO42- type, are characterized by temperatures of 164-221℃, medium salinity in 5-10.8 wt% NaCl, and medium pressure at 410×105 to 661×105 Pa. The contents of Na+-K+ and C1--F-, and ratios of Na+/K+-Cl-/F- in fluid inclusions present good linearity. The ratios of Na+/K+ (4.66-6.71) and Cl-/F- (18.21-31.04) in the fluid inclusions of calcite are relatively high, while those of Na+/K+ (0.29-5.69) and Cl-/F- (5.00-26.0) in the inclusions of sphalerite and pyrite are relatively low. The ratio of Na+/K+ increases in accord with those of Cl-/F-, which indicates that ore-forming fluid of deep source participates in the mineralization. The waters of fluid inclusions have δD values from -43.5‰ to -55.4‰ of calcite. The δ18OV-SMOW values of the ore-forming fluids, calculated values, range from 17.09‰ to 18.56‰ of calcite and 17.80‰ to 23.14‰ for dolomite. δ13CV-PDB values range from -1.94‰ to -3.31‰ for calcite and -3.35‰ to 0.85‰ for the ore-bearing dolomite. These data better demonstrate that the ore-forming fluids were mainly derived from metamorphic water and magmatic hot fluid, in relation to the metamorphism of the Kunyang Group in the basement and magmatic hydrothermalism. The deposit itself might have resulted from ascending cycles of ore-forming fluid, enriched in Pb and Zn. The Huize Zn-Pb- (Ag-Ge) deposits related to carbonate-hosted Zn-Pb sulphides. 展开更多
关键词 Fluid geochemistry fluid inclusion hydrogen oxygen and carbon isotopes Huize Zn-Pb-(Ag-Ge) district yunnan china
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A New Perleidiform(Actinopterygii,Osteichthyes)from the Middle Anisian(Middle Triassic)of Yunnan,South China 被引量:10
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作者 SUN Zuoyu Andrea TINTORI +4 位作者 JIANG Dayong Cristina LOMBARDO Marco RUSCONI HAO Weicheng SUN Yuanlin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期460-470,共11页
Two complete specimens from the Pelsonian (Middle Anisian, Middle Triassic) of Luoping, Yunnan Province, South China are referred to a new actinopterygian genus, Luopingichthys gen. nov., and ascribed to the perleid... Two complete specimens from the Pelsonian (Middle Anisian, Middle Triassic) of Luoping, Yunnan Province, South China are referred to a new actinopterygian genus, Luopingichthys gen. nov., and ascribed to the perleidiform family Polzbergidae based especially on a typical synapomorphy of a peculiar premaxillary-maxillary complex, i.e., the fusion between premaxillary and maxillary along the antero-dorsal margin of the maxillary. The new taxon differs from other deep-bodied representatives of the family, Felberia and Stoppania, in its fusiform or deep fusiform body shape; sickle-shaped preopercular with short infraorbital process; lack of modified scales at the base of the anal fin; the short-based dorsal fin; scarcely ornamented scales; and thin anterior teeth. Based on a redescription of the holotype of the taxon Ctenognathichthys hattichi from the Middle Triassic (Ladinian) Prosanto Formation, Canton Graubiinden, eastern Switzerland, the only known specimen, which shows the same fusion between premaxillary and maxillary, the systematic position of the species is clarified and the taxon is proposed to be a further representative of the family Polzbergidae, and is transferred to the new genus. 展开更多
关键词 actinopterygian new taxon Perleidiformes Middle Triassic ANISIAN yunnan china
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Giant Mineral Deposits and Their Geodynamic Setting in the Lanping Basin, Yunnan, China 被引量:22
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作者 XUEChunji LIUShuwen +2 位作者 CHENYuchuan ZENGRong ZHAOShihua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期368-374,共7页
There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, ... There are giant mineral deposits, including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu, and otherimportant mineral deposits (e.g., Baiyangchang Ag-Cu, Jinman Cu deposits, etc.) in the Lanping Mesozoic-Cenozoic Basin, Yunnan Province, China. The tabular ore-bodies and some veins hosted in terrestrial clastic rocks of the Mesozoic-Cenozoic age and no outcropping of igneous rocks in the giant deposits lead to the proposal of syngenetic origin, but the giant mineral deposits are not stratabound (e.g. MVT, sandstone- and Sedex-type). They formed in a continental red basin with intense crust movement. The mineralization is controlled by structures and lithology and occurs in different strata, and no sedimentary nature and no exhalative sediments are identified in the deposits. The deposits show some relations with organic matter (now asphalt and petroleum) and evaporates (gypsum). The middle-low-temperature (mainly 110℃ to 280℃) mineralization took place at a depth of about 0.9 km to 3.1 km during the early Himalayan (58 to 67 Ma). The salinity of ore-forming fluids is surprisingly low (1.6% to 18.0 wt% (NaCl)eq). Affected by the collision of the Indian and Eurasian plates, the mantle is disturbed under the Lanping Basin. The large-scale mineralization is closely linked with the geodynamics of the crust movement, the mantle and mantle-flux upwelling and igneous activity. Giant mineral deposits and their geodynamic setting are unique in the Lanping Basin. 展开更多
关键词 giant Jinding Zn-Pb deposit giant Baiyangping Ag-Co-Cu deposit ore geology geodynamic setting Lanping Basin yunnan Province china
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New Record of Palaeoscolecids from the Early Cambrian of Yunnan,China 被引量:7
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作者 HU Shixue LI Yong +5 位作者 LUO Huilin FU Xiaoping YOU Ting PANG Jiyuan LIU Qi Michael STEINER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第2期244-248,共5页
A new palaeoscolecid, Guanduscolex minor Hu, Luo et Fu gen. et sp. nov., with preserved soft parts of introvert and intestines comes from the Lower Cambrian Guanshan fauna of Yunnan, South China. Microstructural detai... A new palaeoscolecid, Guanduscolex minor Hu, Luo et Fu gen. et sp. nov., with preserved soft parts of introvert and intestines comes from the Lower Cambrian Guanshan fauna of Yunnan, South China. Microstructural details of the cuticle revealed by scanning electron microscopy (SEM) show that each annulation bears three rows of plates and each plate bears 9-10 marginal and 4-5 central nodes. This discovery sheds new light on the relationships and evolutionary pathway of the palaeoscolecids and other early priapulids. 展开更多
关键词 Palaeoscolecid Guanshan fauna ULTRASTRUCTURE Early Cambrian yunnan china
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Landscape structure and land uese on county level in northeastern Yunnan Province of China——a case study of Huize County 被引量:5
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作者 WANG Jin\|liang, NI Shao\|xiang (College of Geographical Science, Nanjing Normal University, Nanjing 210097, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第3期355-360,共6页
Taking Huize County as an example, the paper analyzed the landscape structure(landscape element structure, landscape type structure, landscape spatial structure, landscape succession structure) and the relations betwe... Taking Huize County as an example, the paper analyzed the landscape structure(landscape element structure, landscape type structure, landscape spatial structure, landscape succession structure) and the relations between landscape structure and land use. It was pointed out that the agriculture should be developed in harmony with the landscape structure in the study area. 展开更多
关键词 landscape structure land use AGRICULTURE yunnan Province china
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Description a new species of the Genus Gonoclostera Butler, 1877(Lepidoptera, Notodontidae) from Yunnan, China
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作者 潘朝辉 李成德 韩辉林 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期387-388,400,共3页
A species of the genus Gonoclostera Butler, 1877, G. fangi sp. nov., from Yunnan, China is described in the present paper. Generic diagnosis and list of world species, as well as the photos of adults and genitalia of ... A species of the genus Gonoclostera Butler, 1877, G. fangi sp. nov., from Yunnan, China is described in the present paper. Generic diagnosis and list of world species, as well as the photos of adults and genitalia of the new species are also provided. 展开更多
关键词 yunnan New species Gonoclostera Pygaerinae china
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Dawazisaurus Brevis, A New Eosauropterygian From the Middle Triassic of Yunnan, China 被引量:3
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作者 CHENG Yen-nien WU Xiao-chun +1 位作者 TAMAKI SATO SHAN His-yin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第2期401-424,共24页
Dawazisaurus brevis(gen. et sp. nov.) is a newly discovered Triassic marine reptile, represented by a complete skeleton from Member II of the Guanling Formation of Luoping, Yunnan Province, China. This paper aims to... Dawazisaurus brevis(gen. et sp. nov.) is a newly discovered Triassic marine reptile, represented by a complete skeleton from Member II of the Guanling Formation of Luoping, Yunnan Province, China. This paper aims to(1) present a thorough description of the species,(2) make a detailed comparison to demonstrate if the species can be referred to any known sauropterygian taxa, and(3) conduct phylogenetic analyses to establish the internal relationships of the species with other sauropterygians. In addition, the discovery of Dawazisaurus provides a chance not only to test the phylogenetic patterns of the Sauropterygia obtained by previous studies but also to evaluate the previous hypotheses on the origin of the sauropterygian groups at different levels. D. brevis is an eosauropterygian, characterized by a unique combination of derived features such as a pair of large nasals joining in the formation of the internarial septum, a short trunk with 16 dorsal vertebrae; the zygapophyses of the trunk vertebrae very small or weakly developed; the posterior margin of the skull roof deeply V-shaped, and an ossified distal carpal 5. Phylogenetic analysis indicates that D. brevis appears to be more closely related to the Nothosauroidea than the Pistosauroidea within the Eosauropterygia. 展开更多
关键词 SAUROPTERYGIA Dawazisaurus brevis Guanling Formation Early Triassic yunnan china
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Characteristics of Underground Water Flow at Different Water Levels in Tianshengan Karst Area, Yunnan, China 被引量:3
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作者 Janja KOGOVEK 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第1期206-212,共7页
Three tracing tests from the same injection point executed at low, medium, and high water levels in the karst aquifer near Tianshengan village, Lunan Stone Forest, Yunnan Province, China, have revealed the basic prope... Three tracing tests from the same injection point executed at low, medium, and high water levels in the karst aquifer near Tianshengan village, Lunan Stone Forest, Yunnan Province, China, have revealed the basic properties of underground water flow. They showed the general directions of water flows; tracer concentrations were observed at six successive points allowing for the calculation of apparent dominant flow velocities at these sections towards the Dalongtan karst spring. For the high water level, the discharge between single sections was between two and 10 times greater than that at low water level. For the medium water level, the flow velocity at different sections was between 1.4 and 3.7 times faster than that at low water level; and for high water level, it was between 1.3 and 2.7 times faster than that at medium water level. The fastest water flow appeared at the first section (23 cm/s at medium water level); and the slowest (0.6 cm/s at low water level) appeared where water flow must cross the Tianshengan fault (north-south direction), and later, a layer of 20-30 m thickness of quartz sandstone and shale clay-stones. It was also possible to calculate the recovery of the tracer for point 4, Dakenyan, where discharge was measured. At the medium water level, 50% of the injected tracer was detected a half-day after its first appearance and at low water level after more than 3 days. The previously published research illustrates the transport velocities of possible contaminants and their solubilities in water at different hydrological conditions. 展开更多
关键词 KARST tracing test underground water flow Lunan yunnan china
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Isotopic Ages of the Carbonatitic Volcanic Rocks in the Kunyang Rift Zone in Central Yunnan,China 被引量:2
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作者 ZHANGYongbei WANGGuilan +4 位作者 NIEJianfeng ZHAOChongshun XUChengyan QIUJiaxiang WangHao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第2期204-211,共8页
The Mesoproterozoic Kunyang rift, which is located on the western margin of the Yangtze platform and the southern section of the Kangdian axis, is a rare massive Precambrian iron-copper polymetallic mineralization zon... The Mesoproterozoic Kunyang rift, which is located on the western margin of the Yangtze platform and the southern section of the Kangdian axis, is a rare massive Precambrian iron-copper polymetallic mineralization zone in China. The Mesoproterozoic Wulu (Wuding-Lufeng) basin in the middle of the rift is an elliptic basin controlled by a ring fracture system. Moreover, volcanic activities in the basin display zonation of an outer ring, a middle ring and an inner ring with carbonatitic volcanic rocks and sub-volcanic dykes discovered in the outer and middle rings. The Sm-Nd isochron ages have been determined for the outer-ring carbonatitic lavas (1685 Ma) and basaltic porphyrite of the radiating dyke swarm (1645 Ma) and the Rb-Sr isochron ages for the out-ring carbonatitic lavas (893 Ma) and the middle-ring dykes (1048 Ma). In combination of the U-Pb concordant ages of zircon (1743 Ma) in trachy-andesite of the corresponding period and stratum (1569 Ma) of the Etouchang Formation, as well as the Rb-Sr isochron age (1024 Ma) and K-Ar age (1186 Ma) of the dykes in the middle ring, the age of carbonarites in the basin is preliminarily determined. It is ensured that all of these carbonatites were formed in the Mesoprotero/oic period, whereby two stages could be identified as follows: in the first stage, carbonatitic volcanic groups, such as lavas, pyroclastic rocks and volcaniclastic sedimentary rocks, were formed in the outer ring; in the second stage, carbonatitic breccias and dykes appeared in the middle ring. The metamorphic age of the carbonatitic lavas in the outer ring was determined to be concurrent with the end of the first stage of the Neoproterozoic period, corresponding to the Jinning movement in central Yunnan. 展开更多
关键词 Kunyang rift central yunnan china Precambrian mineralization zone carbonatitic volcanic rocks isotopic chronology iron and copper deposit CARBONATITE
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A New Basal Sauropod Dinosaur from the Lufeng Basin,Yunnan Province,Southwestern China 被引量:1
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作者 LU Junchang Yoshitsugu KOBAYASHI +1 位作者 LI Tianguang ZHONG Shimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1336-1342,共7页
A new dinosaur Chuxiongosaurus lufengensis gen.et sp.nov.is erected based on a nearly complete skull.The taxon is characterized by the lacrimal perpendicular to the ventral margin of the upper jaw,which is similar to ... A new dinosaur Chuxiongosaurus lufengensis gen.et sp.nov.is erected based on a nearly complete skull.The taxon is characterized by the lacrimal perpendicular to the ventral margin of the upper jaw,which is similar to that of Thecodontosaurus;a depression present on the dorsal profile of the snout behind the naris;the rostral profile of the maxilla slopes continuously towards the rostral tip;and the presence of 25 dentary teeth.It also displays prosauropod characters such as a relatively long skull,the slope of the maxillary rostral profile,and teeth that do not have basically constricted crowns.The new specimen is more basal than Anchisaurus and represents the first basal sauropod dinosaur from the Early Jurassic of China. 展开更多
关键词 taxonomy Chuxiongosaurus lufengensis SAUROPODA JURASSIC yunnan southwestern china
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Modern Sedimentation of Phosphorus and Its Microbial Decomposition and Concentration: An Example from Dianchi Lake, Yunnan, China 被引量:1
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作者 XIAXuehui DONGYEMoxing ZHANGZhuo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期763-767,共5页
Dianchi Lake is one of the lakes with the richest phosphorus source in the world, in which the P2O5 content in the bottom sediments reaches averagely 0.51 wt % and maximally 1.92%. Studies indicate that this: extremel... Dianchi Lake is one of the lakes with the richest phosphorus source in the world, in which the P2O5 content in the bottom sediments reaches averagely 0.51 wt % and maximally 1.92%. Studies indicate that this: extremely P-rich state is attributed mainly to the large volume (as high as hundred thousands of tons) of phosphatic matter coming into the lake as many rivers feeding the lake pass through a vast area of phosphate-mining districts, which then undergo weathering and particularly some human activities, including waste water discharge. When phosphatic matter enters the lake, its grained parts are firstly decomposed by phosphorus-decomposing bacteria, and finally accumulated in some geographically special parts of the lake, such as a bay area where water flow is much more slower than elsewhere in the lake. With the involvement of phosphorus-concentrating bacteria, the accumulated phosphates in the bottom sludge ultimately form phosphate minerals through deep-burial diagenesis. 展开更多
关键词 phosphorus circulation and enrichment microbial mineralization Dianchi Lake yunnan china
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