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Quantitative Analysis of Mineralization-Alteration Index about the Huize Lead-zinc district in Northeast Yunnan, China
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作者 ZHANG Xiaopei HAN Runsheng +3 位作者 ZHAO Dong QIU Wenlong HE Jiaojiao CUI Junhao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期249-250,共2页
1 Introduction The super-large Huize lead-zinc ore district is one of the most representative lead-zinc deposits in Northeastern Yunnan poly-metallic deposit concentration district.So far,studies(Liu and Lin,1999;Han ... 1 Introduction The super-large Huize lead-zinc ore district is one of the most representative lead-zinc deposits in Northeastern Yunnan poly-metallic deposit concentration district.So far,studies(Liu and Lin,1999;Han et al.,2007)on the type of deposits like the Huize lead-zinc deposit,focused on deposit genesis,the sources of metallogenic materials, 展开更多
关键词 PB Zn China Quantitative Analysis of Mineralization-Alteration Index about the Huize Lead-zinc district in northeast yunnan
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Geology and Geochemistry of K-feldspar Veins in Lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold Mineralization
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作者 ZHANG Huichao CHAI Peng +2 位作者 ZHANG Hongrui ZHOU Limin HOU Zengqian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期104-116,共13页
Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mi... Lamprophyres typically appear in hydrothermal gold deposits.The relationship between lamprophyres and gold deposits is investigated widely.Some researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in Zhenyuan.Therefore,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold deposits.Phlogopite in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2,Li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in lamprophyres.The in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from lamprophyres.High large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched mantle.Kfeldspar veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit. 展开更多
关键词 LAMPROPHYRE K-feldspar vein apatite Sr isotope gold Zhenyuan deposit yunnan
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A Brief Discussion on the Development of the Silk-Weaving Industry Along the “Southern Silk Road” in Yunnan
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作者 Lin Kaiqiang 《Contemporary Social Sciences》 2024年第1期18-33,共16页
Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative l... Ancient Yunnan was one of the most significant regions along China’s ancient“Southern Silk Road.”During the Nanzhao period(738–902)of the late Tang Dynasty,Yunnan’s silk-weaving industry underwent a qualitative leap as skilled silk craftsmen from the Bashu area migrated to Yunnan and introduced mulberry planting,silkworm breeding,and advanced silk-weaving techniques from Sichuan to the region.Consequently,people in Yunnan gradually acquired expertise in brocade weaving and embroidery.Many even mastered complex silk-weaving techniques.The development and progress of the silk-weaving industry in the ancient Yunnan region were intricately linked to the economic function and value of silk as both a commodity and currency along the“Southern Silk Road.”The local government in ancient Yunnan was greatly motivated by the economic interests brought by the development of silk-related industries and recognized the significance of developing the local silk industry.They even initiated a campaign to capture skilled silk craftsmen from Sichuan,aiming to foster the growth of the silk-weaving industry in Yunnan.After years of dedicated efforts from the local government in ancient Yunnan,the region emerged as a significant hub for silk production along China’s ancient“Southern Silk Road.”Despite the devastation caused by the wars in other parts of the country,Yunnan’s silk industry continued to thrive and provide ample silk products to sustain trade along this renowned route.In the contemporary era,amidst the decline of the silk-weaving industry in eastern China,Yunnan has proposed an industrial development strategy known as“relocating the silk-weaving industry from east to west.”This involves introducing advanced silk production techniques from the eastern regions into Yunnan to enhance and enrich its local silk industry,thereby establishing it as a traditional national sector and securing a competitive position within the global silk market.The historical experience of Yunnan’s silk industry demonstrated that economic development opportunities can only be seized through proactive endeavors rather than passive anticipation.The modern Yunnan silk industry,which upholds its historical traditions,continues to actively engage in international high-end technical cooperation,thus ensuring the enduring vitality of the ancient“Southern Silk Road.” 展开更多
关键词 Southern Silk Road Bashu area yunnan silk-weaving technique
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Journal of Northeast Agricultural University(English Edition) Instruction to Authors
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《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期F0003-F0003,共1页
Aims and Scope Journal of Northeast Agricultural University(English Edition) is a comprehensive academic journal on agricultural sciences sponsored by Northeast Agricultural University and distributed worldwide. It is... Aims and Scope Journal of Northeast Agricultural University(English Edition) is a comprehensive academic journal on agricultural sciences sponsored by Northeast Agricultural University and distributed worldwide. It is a peer reviewed journal published quarterly and mainly publishes review and research articles that reflect the latest achievements on crop science, horticulture, plant protection, resource and environment, animal science, veterinary medicine, agricultural engineering and technology, agricultural water conservancy, life science, biotechnology and food science. 展开更多
关键词 EDITION northeast JOURNAL
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Epidemiological survey of cystic echinococcosis in southwest China:From the Qinghai-Tibet plateau to the area of Yunnan
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作者 Jin-Rong Zi Dan Xiao +8 位作者 Jia Peng Fang-Wei Wu Jian-Xiong Li Xin-Liu Yan Zheng-Qing Wang Xuan Cai Qian Xu Ben-Fu Li Ya-Ming Yang 《World Journal of Hepatology》 2024年第2期229-240,共12页
BACKGROUND Echinococcosis is prevalent in 9 provinces in Western and Northern China.An epidemiological survey of echinococcosis in 2012 and 2016 showed cases of echinococcosis in Yunnan Province.AIM To understand the ... BACKGROUND Echinococcosis is prevalent in 9 provinces in Western and Northern China.An epidemiological survey of echinococcosis in 2012 and 2016 showed cases of echinococcosis in Yunnan Province.AIM To understand the spatial distribution and epidemiological characteristics of echinococcosis in Yunnan for the prevention and control of echinococcosis and to reduce the risk of infection in Yunnan Province.METHODS Based on the China Information System for Disease Control and Prevention(CISDCP),echinococcosis cases reported from 36 hospitals and 34 Centers for Disease Control were investigated and epidemiologically analyzed from 2021 to 2022.The exclusion criteria included suspected cases,same case only counted once and cases not from Yunnan.A total of 705 cases were investigated,of which 397 cases were suitable for statistical analysis.In these 397 cases,epidemiological investigation was tracked in 187 cases.All data were inputted using double entry in the Excel database,with error correction by double-entry comparison.The data on echinococcosis cases in Yunnan Province were analyzed by ArcGIS 10.1 software to generate a density map of echinococcosis distribution.All statistical analyses were conducted using SPSS 17.0,including the chi-square test,linear regression test and logistic univariate and multivariate regression analyses.RESULTS A total of 397 cases were found in 89 counties in Yunnan Province.The number of cases in the top three prefectures were Dali(38.1%),Diqing(10.1%),and Kunming(8.3%),and the top five counties were Jianchuan(9.1%),Shangri La(8.3%),Eryuan(7.6%),Heqing(6.9%),and Dali Districts(5.0%).There were significant differences between the different areas.The case reporting rate by CISDCP(33.8%)was low;the first case was reported by CISDCP in 2002,and the highest number of cases was 50(2017).Confirmed and clinical cases accounted for 62.5%and 37.5%,respectively.However,90.9%of the cases of hydatid disease were reported by the hospital system,and only 9.1%of the cases of hydatid disease were found in the community through active screening.The difference between the two methods of case detection was statistically significant.Most of the cases of echinococcosis were found in farmers/herdsmen(75.1%)and students(9.1%).In addition,Han(43.6%)and Bai(26.2%)had a higher incidence of infection than other nationalities,and the liver(87.7%)and lung(6.8%)were the most common sites of cyst formation.Among the analyzed cases,187 were epidemiologically analyzed and the clinical symptoms were not obvious in the early stage in 47.1%of cases.The results of logistic regression analysis showed that the age group,education level,presence of dogs in the family(either previously or currently),and handwashing(occasionally or not)were factors related to echinococcosis infection.55.6%of cases were in endemic areas,and 44.4%of cases were in non-endemic areas.Among 83 cases in non-endemic areas,only 4 cases had been to endemic areas and had a history of living,working,travelling,or hunting in echinococcosis epidemic areas.CONCLUSION Cases of echinococcosis were reported throughout the entire Yunnan province,with the majority distributed in Western Yunnan,suggesting that echinococcosis control should be strengthened in this area.We suggest that an epidemiological investigation should be carried out in the future,based on the clues from newly discovered cases in hospitals or from the CISDCP.The newly discovered cases in the hospital provided clues to comprehensively determine the location of cases and where epidemic spot investigation should be conducted. 展开更多
关键词 ECHINOCOCCOSIS CASES Epidemiological analysis yunnan province
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The Unprecedented Extreme Anticyclonic Anomaly over Northeast Asia in July 2021 and Its Climatic Impacts
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作者 Xingyan ZHOU Riyu LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期608-618,共11页
This study investigates the evolution of an extreme anomalous anticyclone(AA)event over Northeast Asia,which was one of the dominant circulation systems responsible for the catastrophic extreme precipitation event in ... This study investigates the evolution of an extreme anomalous anticyclone(AA)event over Northeast Asia,which was one of the dominant circulation systems responsible for the catastrophic extreme precipitation event in July 2021 in Henan,and further explores the significant impact of this AA on surface temperatures beneath it.The results indicate that this AA event over Northeast Asia was unprecedented in terms of intensity and duration.The AA was very persistent and extremely strong for 10 consecutive days from 13 to 22 July 2021.This long-lived and unprecedented AA led to the persistence of warmer surface temperatures beyond the temporal span of the pronounced 500-hPa anticyclonic signature as the surface air temperatures over land in Northeast Asia remained extremely warm through 29 July 2021.Moreover,the sea surface temperatures in the Sea of Japan/East Sea were extremely high for 30 consecutive days from 13 July to 11 August 2021,persisting well after the weakening or departure of this AA.These results emphasize the extreme nature of this AA over Northeast Asia in July 2021 and its role in multiple extreme climate events,even over remote regions.Furthermore,possible reasons for this long-lasting AA are explored,and it is suggested to be a byproduct of a teleconnection pattern over extratropical Eurasia during the first half of its life cycle,and of the Pacific-Japan teleconnection pattern during the latter half. 展开更多
关键词 anomalous anticyclone northeast Asia surface air temperatures sea surface temperatures
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Monitoring Surface Water Change in Northeast China in 1999–2020:Evidence from Satellite Observation and Refined Classification
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作者 LIU Kai ZHANG Dapeng +3 位作者 CHEN Tan CUI Peipei FAN Chenyu SONG Chunqiao 《Chinese Geographical Science》 SCIE CSCD 2024年第1期106-117,共12页
As a typical region with high water demand for agricultural production,understanding the spatiotemporal surface water changes in Northeast China is critical for water resources management and sustainable development.H... As a typical region with high water demand for agricultural production,understanding the spatiotemporal surface water changes in Northeast China is critical for water resources management and sustainable development.However,the long-term variation characteristics of surface water of different water body types in Northeast China remain rarely explored.This study investigated how surface water bodies of different types(e.g.,lake,reservoir,river,coastal aquaculture,marsh wetland,ephemeral water) changed during1999–2020 in Northeast China based on various remote sensing-based datasets.The results showed that surface water in Northeast China grew dramatically in the past two decades,with an equivalent area increasing from 24 394 km^(2) in 1999 to 34 595 km^(2) in 2020.The surge of ephemeral water is the primary driver of surface water expansion,which could ascribe to shifted precipitation pattern.Marsh wetlands,rivers,and reservoirs experienced a similar trend,with an approximate 20% increase at the interdecadal scale.By contrast,coastal aquacultures and natural lakes remain relatively stable.This study is expected to provide a more comprehensive investigation of the surface water variability in Northeast China and has important practical significance for the scientific management of different types of surface water. 展开更多
关键词 surface water spatiotemporal variation water body classification remote sensing northeast China
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How Does Urban Shrinkage Affect Land Use Efficiency?A Case Study of Shrinking Cities in Northeast China
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作者 XIE Mingke FENG Zhangxian +2 位作者 SONG Yang GUAN Haoming WANG Shijun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期34-51,共18页
The effect of urban shrinkage has gradually become a new topic.Theoretically,urban shrinkage may exert great influence on land use efficiency(LUE)through various urban subsystems,but there is currently limited researc... The effect of urban shrinkage has gradually become a new topic.Theoretically,urban shrinkage may exert great influence on land use efficiency(LUE)through various urban subsystems,but there is currently limited research examining these pathways.Using the Super-SBM-Undesirable model and the Structural Equation Model(SEM),this study calculates the LUE of shrinking cities in Northeast China and simulates the process of urban shrinkage affecting LUE.To quantify the process of urban shrinkage affecting LUE,three mediation variables,namely the economy,public services,and innovation,are used as latent variables to apply SEM.The results show that urban shrinkage will affect LUE through a direct path and indirect paths.In the direct path,urban shrinkage leads to an improvement in LUE.In the indirect paths,the economy and innovation will transmit the negative effect of urban shrinkage on LUE,while public services will reverse this effect.An important contribution of this study is that it quantifies the paths of urban shrinkage affecting LUE,thereby expanding the understanding of urban shrinkage effect and laying a foundation for the sustainable development of shrinking cities. 展开更多
关键词 urban shrinkage land use efficiency Super-SBM-Undesirable model Structural Equation Model(SEM) northeast China
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Deep tectonics and seismogenic mechanisms of the seismic source zone of the Jishishan M_(s)6.2 earthquake on December 18,2023,at the northeast margin of the Tibetan Plateau
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作者 Qiong Wang ShuYu Li +3 位作者 XinYi Li Yue Wu PanPan Zhao Yuan Gao 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期514-521,共8页
On December 18,2023,an M_(s)6.2 earthquake occurred in Jishishan,Gansu Province,China.This earthquake happened in the eastern region of the Qilian Orogenic Belt,which is situated at the forefront of the NE margin of t... On December 18,2023,an M_(s)6.2 earthquake occurred in Jishishan,Gansu Province,China.This earthquake happened in the eastern region of the Qilian Orogenic Belt,which is situated at the forefront of the NE margin of the Tibetan Plateau(i.e.,Qinghai-Tibet Plateau),encompassing a rhombic-shaped area that intersects the Qilian-Qaidam Basin,Alxa Block,Ordos Block,and South China Block.In this study,we analyzed the deep tectonic pattern of the Jishishan earthquake by incorporating data on the crustal thickness,velocity structure,global navigation satellite system(GNSS)strain field,and anisotropy.We discovered that the location of the earthquake was related to changes in the crustal structure.The results showed that the Jishishan M_(s)6.2 earthquake occurred in a unique position,with rapid changes in the crustal thickness,Vp/Vs,phase velocity,and S-wave velocity.The epicenter of the earthquake was situated at the transition zone between high and low velocities and was in proximity to a low-velocity region.Additionally,the source area is flanked by two high-velocity anomalies from the east and west.The principal compressive strain orientation near the Lajishan Fault is primarily in the NNE and NE directions,which align with the principal compressive stress direction in this region.In some areas of the Lajishan Fault,the principal compressive strain orientations show the NNW direction,consistent with the direction of the upper crustal fast-wave polarization from local earthquakes and the phase velocity azimuthal anisotropy.These features underscore the relationship between the occurrence of the Jishishan M_(s)6.2 earthquake and the deep inhomogeneous structure and deep tectonic characteristics.The NE margin of the Tibetan Plateau was thickened by crustal extension in the process of northeastward expansion,and the middle and lower crustal materials underwent structural deformation and may have been filled with salt-containing fluids during the extension process.The presence of this weak layer makes it easier for strong earthquakes to occur through the release of overlying rigid crustal stresses.However,it is unlikely that an earthquake of comparable or larger magnitude would occur in the short term(e.g.,in one year)at the Jishishan east margin fault. 展开更多
关键词 Jishishan Ms 6.2 earthquake crustal structure anisotropy stress and strain seismogenic mechanism northeast margin of the Tibetan Plateau
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Study on the Promotion of Digital Trade to Northeast Asian Regional Economy
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作者 Yating Mo Zhaoxia Zhang 《Proceedings of Business and Economic Studies》 2024年第1期162-168,共7页
Society is currently transitioning from the era of informatization and digitization to the era of intelligence.Advanced technologies such as artificial intelligence,the Internet of Things,and big data are permeating e... Society is currently transitioning from the era of informatization and digitization to the era of intelligence.Advanced technologies such as artificial intelligence,the Internet of Things,and big data are permeating every aspect of production and life.This penetration presents a rare opportunity for the development of digital trade and catalyzes innovation in traditional trade patterns.This paper first analyzes the inevitability of digital trade development in Northeast Asia.Secondly,it delves into the challenges faced by digital trade development and explores in-depth the promotion strategy for digital trade’s impact on the economic development of the Northeast Asia region,providing insights from various perspectives for reference. 展开更多
关键词 Digital trade northeast Asian regional economy PROMOTION
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Early Silurian(Telychian)rugose coral fauna of Daguan area,northeast Yunnan Province,China
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作者 CHEN Jianqiang HE Xinyi TANG Lan 《Frontiers in Biology》 CSCD 2006年第3期332-344,共13页
Study on rugose coral fauna of the Sifengya Formation(early Telychian)and Daluzhai Formation(mid-late Telychian)in Daguan area,northeast Yunnan Province,China was carried out.Rugose coral fauna of the Sifengya Formati... Study on rugose coral fauna of the Sifengya Formation(early Telychian)and Daluzhai Formation(mid-late Telychian)in Daguan area,northeast Yunnan Province,China was carried out.Rugose coral fauna of the Sifengya Formation included 18 genera and 34 species,while Daluzhai Formation with nine genera,ten species.We described rugose coral fauna(12 genera,19 species)including one new genus and five new species,i.e.Protoketophyllum daguanense gen.et sp.nov.,Crassilasma huanggexiense sp.nov.,Pseudophaulactis heae sp.nov.,P.convolutus sp.nov.,and Shensiphyllum minor sp.nov..The characteristics and geological significance of rugose coral fauna of Sifengya Formation and Daluzhai Formation were analyzed.Particularly,rugose coral fauna of the Sifengya Formation represent early Telychian rugosan fauna in the Upper Yangtze region and improve the sequences of early Silurian(Llandovery)rugose coral assemblages in Yangtze region.It is therefore very meaningful to further analyze radiation period of rugose coral fauna in such epoch. 展开更多
关键词 rugose coral fauna TELYCHIAN SILURIAN Daguan northeast yunnan Province China
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Differences in shale gas accumulation process and its significance in exploration of Lower Silurian Longmaxi Formation in northeast Yunnan
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作者 Shangbin CHEN Huijun WANG +3 位作者 Yang WANG Tianguo JIANG Yingkun ZHANG Zhuo GONG 《Frontiers of Earth Science》 SCIE CSCD 2021年第2期343-359,共17页
The study and exploration practice of shale gas accumulation has focused on the static system comparison,key parameters analysis,reservoir characteristics,enrichment mode etc.However,the research on dynamic recovery f... The study and exploration practice of shale gas accumulation has focused on the static system comparison,key parameters analysis,reservoir characteristics,enrichment mode etc.However,the research on dynamic recovery from the original hydrocarbon generation of shale gas to the present gas reservoir is still lacking.The burial history of shale gas reservoir can reflect the overall dynamic process of early formation and later transformation of shale gas reservoir.It controls the material basis of shale gas,the quality of reservoir physical properties,preservation conditions,gas content and formation energy,which is the core and foundation of shale gas accumulation process research.Herein,based on the five typical wells data in the Northeast Yunnan,including geochronological data,measured Ro values,core description records,well temperature data,paleoenvironment,paleothermal,etc.,the burial history,thermal evolution history and hydrocarbon generation history of the Lower Silurian Longmaxi Formation were systematically restored via back stripping method and EASY%Ro model.The results show that 1)the differences in the burial history of marine shale in Longmaxi Formation can be divided into syncline type and anticline type.2)The shale gas accumulation process can be divided into four stages,namely the sourcereservoir-cap sedimentation period,initial accumulation period,main accumulation period,and adjustment period.3)Based on the characteristics of burial history and preservation conditions,the areas with wide and gentle anticline,far away from the denudation area,and buried deeply with good fault sealing ability are priority structural locations for the shale gas exploration in northeast Yunnan. 展开更多
关键词 shale gas accumulation process exploration significance Longmaxi Formation(Fm.) northeast yunnan
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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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QUATERNARY GLACIATION SERIES ANDGLACIAL LANDFORM IN GONGWANG MOUNTAINS INNORTHEAST PART OF YUNNAN PROVINCE, CHINA 被引量:1
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作者 况明生 《Chinese Geographical Science》 SCIE CSCD 1997年第2期180-190,共11页
The Gongwang Mountains is situated in the northeast part of Yunnan Plovince. In the mountain, glaciation once occirred above 3100 m a. s. l. in the Quaiernary. The typical glacial remains are mainly concentrated in Ji... The Gongwang Mountains is situated in the northeast part of Yunnan Plovince. In the mountain, glaciation once occirred above 3100 m a. s. l. in the Quaiernary. The typical glacial remains are mainly concentrated in Jiaozishan - and Yaojingtang - Niudongping area. The glacial landforms were mainly cirque, trough valley and lateral moraine. Glacial type was alpine cirque glacier and according to morphogenetic relation of the glacial landforms, the Quaternary glaciation should be separated into two periods: last glaciation (containing two stages of late and maximum glaciation) and penultimate in the Gongwang Mountain in northeast part of Yunnan Province of China. 展开更多
关键词 REMAINS of glacier the QUATERNARY GLACIATION SERIES the Gongwang Mountains yunnan Province
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Composition and mode of occurrence of minerals in Late Permian coals from Zhenxiong County,northeastern Yunnan,China 被引量:4
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作者 Tian Li Shi-Feng Dai +3 位作者 Jian-Hua Zou Sen Zhang He-Hing Tian Li-Xin Zhao 《International Journal of Coal Science & Technology》 EI CAS 2014年第1期13-22,共10页
Minerals in the Late Permian coals from the Niuchang-Yigu mining area,Zhenxiong County,northeastern Yunnan,China,were investigated using optical microscopy and low temperature ashing plus X-ray diffraction(LTA?XRD).Th... Minerals in the Late Permian coals from the Niuchang-Yigu mining area,Zhenxiong County,northeastern Yunnan,China,were investigated using optical microscopy and low temperature ashing plus X-ray diffraction(LTA?XRD).The results showed that minerals in the coal LTAs are mainly quartz,kaolinite,chamosite,mixed-layer illite/smectite(I/S),pyrite,and calcite,with trace amounts of marcasite,dolomite,and bassanite.The authigenic quartz generally occurs in collodetrinite or as a filling in cleats or cell cavities.This silica was mainly derived from aqueous solutions produced by the weathering of basaltic rocks in the Kangdian Upland and from hydrothermal fluids.The presence of b-quartz paramorph grains in collodetrinite probably indicates that these grains were detrital and came from a volcanic ash.Clay minerals are generally embedded in collodetrinite and occur as cell-fillings.Pyrite occurs as framboidal,anhedral,and euhedral grains and a cell-filling.The coals are high in pyrite and the high pyrite content probably results from seawater invading during the stage of peat accumulation.Calcite generally occurs as vein-fillings,indicating an epigenetic origin. 展开更多
关键词 Late Permian coals Minerals in coal Zhenxiong of yunnan
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Ore-Controlling Structural Features of Lead-zinc Deposit in Jinniuchang of Northeast Yunnan, China
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作者 孔志岗 ZHU Jie-yong ZHU Lin-sheng 《矿物学报》 CAS CSCD 北大核心 2013年第S2期157-157,共1页
1 Introduction Multi-metal contained Lead-zinc deposits in northeast Yunnan,China,is located in a joint place of the Circum-Pacific tectonic domain and Tethyan tectonic domain.This joint place is featured by complex g... 1 Introduction Multi-metal contained Lead-zinc deposits in northeast Yunnan,China,is located in a joint place of the Circum-Pacific tectonic domain and Tethyan tectonic domain.This joint place is featured by complex geological structure,unique geological characteristic,and multiple lead-zinc mineral deposits,which are discretely and linearly distributed along the cracks of several main fracture zones.Most of the lead-zinc ores were filled into the 展开更多
关键词 TECTONIC northeast northeast filled contained featured cracking DESTRUCTION SURROUNDING PALEOZOIC
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Subseasonal Prediction of Early-summer Northeast Asian Cut-off Lows by BCC-CSM2-HR and GloSea5 被引量:1
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作者 Yu NIE Jie WU +4 位作者 Jinqing ZUO Hong-Li REN Adam A.SCAIFE Nick DUNSTONE Steven C.HARDIMAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第11期2127-2134,共8页
Northeast Asian cut-off lows are crucial cyclonic systems that can bring temperature and precipitation extremes over large areas.Skillful subseasonal forecasting of Northeast Asian cut-off lows is of great importance.... Northeast Asian cut-off lows are crucial cyclonic systems that can bring temperature and precipitation extremes over large areas.Skillful subseasonal forecasting of Northeast Asian cut-off lows is of great importance.Using two dynamical forecasting systems,one from the Beijing Climate Center(BCC-CSM2-HR)and the other from the Met Office(GloSea5),this study assesses simulation ability and subseasonal prediction skill for early-summer Northeast Asian cut-off lows.Both models are shown to have good ability in representing the spatial structure of cut-off lows,but they underestimate the intensity.The skillful prediction time scales for cut-off low intensity are about 10.2 days for BCC-CSM2-HR and 11.4 days for GloSea5 in advance.Further examination shows that both models can essentially capture the initial Rossby wave train,rapid growth and decay processes responsible for the evolution of cut-off lows,but the models show weaker amplitudes for the three-stage processes.The underestimated simulated strength of both the Eurasian midlatitude and East Asian subtropical jets may lead to the weaker local eddy-mean flow interaction responsible for the cut-off low evolution. 展开更多
关键词 northeast Asia cut-off lows subseasonal prediction skill jet stream
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An Extreme Gale Event in East China under the Arctic Potential Vorticity Anomaly through the Northeast China Cold Vortex 被引量:1
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作者 Wei TAO Linlin ZHENG +1 位作者 Ying HAO Gaoping LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第12期2169-2182,共14页
Arctic changes influence not only temperature and precipitation in the midlatitudes but also contribute to severe convection.This study investigates an extreme gale event that occurred on 30 April 2021 in East China a... Arctic changes influence not only temperature and precipitation in the midlatitudes but also contribute to severe convection.This study investigates an extreme gale event that occurred on 30 April 2021 in East China and was forced by an Arctic potential vorticity(PV)anomaly intrusion.Temperature advection steered by storms contributed to the equatorward propagation of Arctic high PV,forming the Northeast China cold vortex(NCCV).At the upper levels,a PV southward intrusion guided the combination of the polar jet and the subtropical jet,providing strong vertical wind shear and downward momentum transportation to the event.The PV anomaly cooled the upper troposphere and the northern part of East China,whereas the lower levels over southern East China were dominated by local warm air,thus establishing strong instability and baroclinicity.In addition,the entrainment of Arctic dry air strengthened the surface pressure gradient by evaporation cooling.Capturing the above mechanism has the potential to improve convective weather forecasts under climate change.This study suggests that the more frequent NCCV-induced gale events in recent years are partly due to high-latitude waviness and storm activities,and this hypothesis needs to be investigated using more cases. 展开更多
关键词 PV anomaly Arctic storm northeast China cold vortex convection extreme gale
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Ore-controlling Regularitiesof Structureinthe Lehong Lead-zinc Deposit, Northeastern Yunnan
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作者 CUI Junhao HAN Runsheng +1 位作者 ZHAO Dong ZHANG Xiaopei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期197-198,共2页
1 Introduction The Lehonglead-zincdeposit is a large-sized Pb-Zn depositnewly found in recent years in the Sichuan-Yunnan-Guizhou Lead-zinc Poly-metallic Mineralization Area,which occurrenceis
关键词 REE PB ZN northeastern yunnan Ore-controlling Regularitiesof Structureinthe Lehong Lead-zinc Deposit
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The Coordinated Influence of Indian Ocean Sea Surface Temperature and Arctic Sea Ice on Anomalous Northeast China Cold Vortex Activities with Different Paths during Late Summer 被引量:1
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作者 Yitong LIN Yihe FANG +3 位作者 Chunyu ZHAO Zhiqiang GONG Siqi YANG Yiqiu YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第1期62-77,共16页
The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NC... The Northeast China cold vortex(NCCV)during late summer(from July to August)is identified and classified into three types in terms of its movement path using machine learning.The relationships of the three types of NCCV intensity with atmospheric circulations in late summer,the sea surface temperature(SST),and Arctic sea ice concentration(SIC)in the preceding months,are analyzed.The sensitivity tests by the Community Atmosphere Model version 5.3(CAM5.3)are used to verify the statistical results.The results show that the coordination pattern of East Asia-Pacific(EAP)and Lake Baikal high pressure forced by SST anomalies in the North Indian Ocean dipole mode(NIOD)during the preceding April and SIC anomalies in the Nansen Basin during the preceding June results in an intensity anomaly for the first type of NCCV.While the pattern of high pressure over the Urals and Okhotsk Sea and low pressure over Lake Baikal during late summer-which is forced by SST anomalies in the South Indian Ocean dipole mode(SIOD)in the preceding June and SIC anomalies in the Barents Sea in the preceding April-causes the intensity anomaly of the second type.The third type is atypical and is not analyzed in detail.Sensitivity tests,jointly forced by the SST and SIC in the preceding period,can well reproduce the observations.In contrast,the results forced separately by the SST and SIC are poor,indicating that the NCCV during late summer is likely influenced by the coordinated effects of both SST and SIC in the preceding months. 展开更多
关键词 machine learning method northeast China cold vortex path classification Indian Ocean sea surface temperature Arctic sea ice model sensitivity test
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