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Wind farms increase land surface temperature and reduce vegetation productivity in the Inner Mongolia
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作者 Luyao Liu Pengtao Liu +3 位作者 Jiawei Yu Gang Feng Qing Zhang Jens-Christian Svenning 《Geography and Sustainability》 CSCD 2024年第3期319-328,共10页
Wind power has been developing rapidly as a key measure to mitigate human-driven global warming.The under-standing of the development and impacts of wind farms on local climate and vegetation is of great importance fo... Wind power has been developing rapidly as a key measure to mitigate human-driven global warming.The under-standing of the development and impacts of wind farms on local climate and vegetation is of great importance for their rational use but is still limited.In this study,we combined remote sensing and on-site investigations to identify wind farm locations in Inner Mongolia and performed landscape pattern analyses using Fragstats.We explored the impacts of wind farms on land surface temperature(LST)and vegetation net primary productivity(NPP)between 1990 and 2020 by contrasting these metrics in wind farms with those in non-wind farm areas.The results showed that the area of wind farms increased rapidly from 1.2 km2 in 1990 to 10,755 km2 in 2020.Spatially,wind farms are mainly clustered in three aggregation areas in the center.Further,wind farms increased nighttime LST,with a mean value of 0.23℃,but had minor impacts on the daytime LST.Moreover,wind farms caused a decline in NPP,especially over forest areas,with an average reduction of 12.37 GC/m^(2).Given the impact of wind farms on LST and NPP,we suggest that the development of wind farms should fully consider their direct and potential impacts.This study provides scientific guidance on the spatial pattern of future wind farms. 展开更多
关键词 Wind farm Landscape pattern LST NPP inner mongolia
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The Influence of Plant Diversity and Functional Composition on Ecosystem Stability of Four Stipa Communities in the Inner Mongolia Plateau 被引量:65
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作者 白永飞 李凌浩 +1 位作者 黄建辉 陈佐忠 《Acta Botanica Sinica》 CSCD 2001年第3期280-287,共8页
The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner M... The main purpose of this study was to examine the effects of plant species diversity and functional composition (the identity of the plant functional groups) on ecosystem stability of Stipa, communities in the Inner Mongolia Plateau. The research work was based on a 12-year study (from 1984 to 1995) of species abundance, diversity, and primary productivity of four Stipa communities, i.e. S. baicalensis Roshev., S. grandis P. Smirn., S, krylovii Roshev., and S. klemenzii Roshev. respectively. The Shnnon-Wiener index was used as a measurement of plant diversity, while functional composition was used to differentiate the functional groups that were included in the communities. The plant species of four Stipa communities were classified into functional groups based on the differences in life forms and ecological groups, which influence their performance in resource requirements, seasonality of growth, tolerance to water stress, and life history. Plant species were classified into five functional groups based on their differences in life form, shrubs and half shrubs, perennial bunch grasses, perennial rhizome grasses, forbs, annuals and biennials. Based on their differences in water requirement these species were classified into four functional groups: xerads, intermediate xerads, intermediate mesophytes, and mesophytes. The results showed: 1) Plant species diversity stabilized ecosystem processes. Shannon-Wiener index were 2.401 4, 2.172 0, 1.624 8, 0.354 3 from S. baicalensis community to S. grandis, S. krylovii and S. klemenzii community, respectively. The dynamics of the aboveground net primary productivity (ANPP) for a 12-year's period showed a reverse pattern, the coefficients of variation of the four communities were 21.94%, 20.63%, 29.21% and 39.72% respectively. 2) The Life form functional group component of diversity was a greater determinant of the ecosystem processes than the species component of diversity. The effects of perennial bunch grasses, perennial rhizome grasses and forbs on community stability were highly significant. 3) The ecological group component of diversity was also a great determinant of the ecosystem processes. The effects of xerads, intermediate xerads, and mesophytes on community stability were also very strong. 展开更多
关键词 inner mongolia Plateau Stipa communities the aboveground net primary productivity species diversity functional composition
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Temporal-spatial Changes in Inner Mongolian Grassland Degradation during Past Three Decades 被引量:10
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作者 张清雨 吴绍洪 +1 位作者 赵东升 戴尔阜 《Agricultural Science & Technology》 CAS 2013年第4期676-683,共8页
[Objective] This study aimed to analyze the temporal-spatial variation of Inner Mongolian grassland degradation during past three decades. [Method] The dis- tribution characteristics of grassland were described by lan... [Objective] This study aimed to analyze the temporal-spatial variation of Inner Mongolian grassland degradation during past three decades. [Method] The dis- tribution characteristics of grassland were described by land use types supervised classification with TM/ETM. Then, temporal-spatial changes of grassland coverage were quantified by the mean of maximum vegetation coverage in last 30 years. Lastly, the grassland degradation reasons were explored through statistic analysis between the grassland coverage and precipitation, temperature and grazing intensity. [Result] The grassland degradation index of Inner Mongolia was increased from 1.38 to 1.68, and the smallest was 1.28 in 2005s. Grassland degradation and improve- ment were concurrent after 1980s, but grassland degradation was the major change trend for Inner Mongolia grassland. The area of grassland degradation was enlarged from 18.08×10^4 km2 in 1980s to 22.47×10^4 km2 in 2010s on the whole and distribu- tion range was shifted from central-eastern to west in Inner Mongolia that mainly distributed on Hulun Buir and Xilin Gol grassland in 1980s and Ordos and Alax grassland in 2010s. The grassland area of degradation had a rising trend form 1980s to 1995s, then reduced to 10.8x104 km2 in 2005s, and decreased in 2010s, which mainly speared in the west of Xilin Gol grassland. [Conclusion] Inner Mongo-lian grassland degradation were become more seriously in last 30 years because that temperature, precipitation and graze intensities change, which not performance on decreasing coverage but grassland areas. 展开更多
关键词 Grassland degradation Temporal-spatial change Influencing factor inner mongolia
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Storage of biomass and net primary productivity in desert shrubland of Artemisia ordosica on Ordos Plateau of Inner Mongolia, China 被引量:4
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作者 金钊 齐玉春 董云社 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期298-300,共3页
Biomass and net primary productivity (NPP) are two important parameters in determining ecosystem carbon pool and carbon sequestration. The biomass storage and NPP in desert shrubland of Artemisia ordosica on Ordos P... Biomass and net primary productivity (NPP) are two important parameters in determining ecosystem carbon pool and carbon sequestration. The biomass storage and NPP in desert shrubland of Artemisia ordosica on Ordos Plateau were investigated with method of harvesting standard size shrub in the growing season (June-October) of 2006. Results indicated that above- and belowground biomass of the same size shrubs showed no significant variation in the growing season (p〉0.1), but annual biomass varied significantly (p〈 0.01). In the A. ordosica community, shrub biomass storage was 699.76-1246.40 g.m^-2 and annual aboveground NPP was 224.09 g-m^-2·a^-1. Moreover, shrub biomass and NPP were closely related with shrub dimensions (cover and height) and could be well predicted by shrub volume using power regression. 展开更多
关键词 Shrub biomass Net primary productivity Artemisia ordosica community Ordos Plateau inner mongolia
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Analysis of Heavy Metal Content in Food Crops Planted Along the Shaanxi Inner Mongolia Expressway 被引量:2
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作者 艾海舰 张雄 +2 位作者 刘翠英 纪晓玲 卜耀军 《Agricultural Science & Technology》 CAS 2009年第3期108-111,119,共5页
To understand the effect of the running of Shaanxi Inner Mongolia Expressway on food crops planted along the sides, we determined the heavy metal contents(Zn, Pb, Cu and Cb) in the digestion solutions of the root, ste... To understand the effect of the running of Shaanxi Inner Mongolia Expressway on food crops planted along the sides, we determined the heavy metal contents(Zn, Pb, Cu and Cb) in the digestion solutions of the root, stem and leaf from rice and corn. The results showed that highway promoted the accumulation of heavy metal elements in corn and rice. Compared with the CKs(crops produced where no highway extend), contents of heavy metal elements in two crops tested from two sampling sites were both over standard. This indicates that food crops planted within 100 m away from the highway are been polluted by heavy metals, which is directly related with the running of Shaanxi Inner Mongolia Expressway. Based on this, the areas within 100 m away from the highway are not suggested to cultivate food crops. 展开更多
关键词 Shaanxi inner mongolia Expressway Food crop Heavy metal
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Relationships between bird communities and vegetation structure in Honghuaerji, northern Inner Mongolia 被引量:2
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作者 王文 丸山直树 +2 位作者 刘伯文 森本英人 高中信 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期294-298,337,共5页
The survey on bird communities was conducted by the belt-style method in six different sample plots in the Honghua抏rji Forests area in the northern Inner Mongolia in June 2001 and totally 28 bird species were recorde... The survey on bird communities was conducted by the belt-style method in six different sample plots in the Honghua抏rji Forests area in the northern Inner Mongolia in June 2001 and totally 28 bird species were recorded. Vegetation investigation was carried out in five 10 m×10 m quadrats at each plot. The asymptotic regression function formulae were adopted to identify the relationships between the vegetation coverage and the numbers of bird species and individuals. The analytical results showed that the changes of species number and density of bird as well as the formation of bird communities follow the changes of forest type and the total foliage. Both the number of bird species and their density decreased with the de-crease of total foliage. The similarity of bird community was very low at the breeding time. In the same classification of cluster, no similarity was higher than 0.65, which indicated that the composition of species had a great difference between all the bird communities. The bird breeding density was closely related to forest growth stage. From the bare grassland ecosystem to cli-max ecosystem, the density of bird species showed a gradually increasing trend. 展开更多
关键词 Bird community Vegetation structure Honghua抏rji Northern inner mongolia
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New ratite eggshell material from the Miocene of Inner Mongolia,China
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作者 王烁 胡莹 王璐 《Chinese Birds》 2011年第1期18-26,共9页
Some Miocene ratite eggshell fragments from Gashunyinadege (about 17.5 Ma) and Baogedawula (7.11 ± 0.48 Ma), Inner Mongolia, China, are described. The outer surfaces of eggshell fragments from Gashunyinadege are ... Some Miocene ratite eggshell fragments from Gashunyinadege (about 17.5 Ma) and Baogedawula (7.11 ± 0.48 Ma), Inner Mongolia, China, are described. The outer surfaces of eggshell fragments from Gashunyinadege are smooth with a sting pore pattern, while their entire thickness is around 2.12 mm. In a cross-sectional view, the surface crystal layer is very thin and the ratio of cone layer to the those from Gashunyinadege, but seem much thinner and have a lower pore density. Both characteristics fit aepyornithid-type eggshells, implying that the distribution of aepyornithid-type eggshells can be extended to East Asia. The sediments at Gashunyinadege date to approximately 17.5 Ma, implying that the specimens from this locality are relatively early examples of aepyornithid-type eggshells. Aepyornithidtype eggshells seem to have appeared in Eurasia much earlier than struthionid-type eggshells. The faunal compositions in the two localities reflect gradual drying of the Mongolian plateau during the Miocene. A reduction in the number of pores 10 Ma ago, probably occurred in response to this drying process. 展开更多
关键词 China inner mongolia MIOCENE ratite eggshell
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Preview of the No.1148 Ramsar Site on the Ordos upland of western Inner Mongolia
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作者 何芬奇 任永奇 白秀芳 《Chinese Birds》 2010年第1期80-81,共2页
The Taolimiao-Alashan Nur (T-A Nur), of about 10 km2 a brackish lake located on the Ordos upland of western Inner Mongolia, northern China, used to
关键词 No.1148 Ramsar Site the Ordos upland western inner mongolia
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Analysis on Climate Change Features of East of Inner Mongolia in Recent 40 Years 被引量:1
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作者 苏立娟 邓晓东 +2 位作者 达布希拉图 闫宾 毕力格 《Meteorological and Environmental Research》 CAS 2010年第7期51-53,共3页
The trend analysis method was adopted to study the spatial distribution and change trend of temperature,rain,rain days,extreme rain case and extreme temperature based on meteorology data of 48 ground stations in east ... The trend analysis method was adopted to study the spatial distribution and change trend of temperature,rain,rain days,extreme rain case and extreme temperature based on meteorology data of 48 ground stations in east of Inner Mongolia from 1951 to 2005.The results showed that temperature of east of Inner Mongolia was improving,and improving degree of extremely minimum temperature was higher than extremely maximum one.Rain of east of Hulunbuir and southwest of Chifeng was more markedly improving and was most markedly decreasing in Tongliao.Rain days were decreasing at majority area,while increasing at southwest,east and north of Hulunbuir.The one which was above 25 mm showed an increasing tendency. 展开更多
关键词 inner mongolia EASTERN Temperature PRECIPITATION FEATURE China
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Genetic Analysis on the Lambing Effects of Ewe Inner Mongolia Cashmere Goat 被引量:2
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作者 周蕾 李金泉 +3 位作者 张文广 梅步俊 张燕军 张永斌 《Agricultural Science & Technology》 CAS 2008年第6期118-120,共3页
[Objective] The aim of this study was to explore the genetic law of litter size of Inner Mongolia Cashmere Goat.[Method] A total of 22 721 litter records from 3 044 mothers were statistically analyzed.[Result] As show... [Objective] The aim of this study was to explore the genetic law of litter size of Inner Mongolia Cashmere Goat.[Method] A total of 22 721 litter records from 3 044 mothers were statistically analyzed.[Result] As shown by the least square variance analysis,the sex,parity and birth type had significant effect on lamb birth weight.As indicated by restricted maximum likelihood method,the parity,population and maternal effect influenced litter size significantly.The birth weight heritability of single lamb,twins and total was 0.16,0.40 and 0.17,respectively.[Conclusion] The study provided a certain basis for the establishment of Inner Mongolia Cashmere Goat line with superior reproductive performance. 展开更多
关键词 inner mongolia CASHMERE GOAT LITTER size Birth weight HERITABILITY
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Radiometric Dating of Ignimbrite from Inner Mongolia Provides no Indication of a Post-Middle Jurassic Age for the Daohugou Beds 被引量:30
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作者 GAO Ke-Qin REN Dong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期42-45,共4页
Lacustrine deposits exposed at Daohugou, Inner Mongolia, China, have yielded superbly preserved vertebrate fossils. The fossil beds were first misinterpreted as of Early Cretaceous age, based on alleged occurrences of... Lacustrine deposits exposed at Daohugou, Inner Mongolia, China, have yielded superbly preserved vertebrate fossils. The fossil beds were first misinterpreted as of Early Cretaceous age, based on alleged occurrences of key fossils of the Jehol Biota. Compelling evidence revealed by more rigorous research involving regional biostratigraphy, radiometric dating, and paleontology supports the Middle Jurassic age of the fossil beds. Despite the awesome evidence for the Middle Jurassic age of the Daohugou beds, the age dispute has been resurrected recently by invoking an overturned stratigraphic sequence. A careful review of the data, however, found no evidence that this sequence has been overturned. In addition, many of the assumptions, on which the conjecture of the fossil beds being post- Middle Jurassic is imprudently based, are self-contradictory or otherwise misleading. Thus, the post- Middle Jurassic age of the Daohugou beds as an unfounded conclusion can readily be dismissed. 展开更多
关键词 Daohugou beds inner mongolia Middle Jurassic age dispute radlometric dating
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Carboniferous-Permian Stratigraphy and Sedimentary Environment of Southeastern Inner Mongolia,China:Constraints on Final Closure of the Paleo-Asian Ocean 被引量:17
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作者 ZHU Junbin REN Jishun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第3期832-856,共25页
In this paper we discuss the timing of final closure of the Paleo-Asian Ocean based on the field investigations of the Carboniferous-Permian stratigraphic sequences and sedimentary environments in southeastern Inner M... In this paper we discuss the timing of final closure of the Paleo-Asian Ocean based on the field investigations of the Carboniferous-Permian stratigraphic sequences and sedimentary environments in southeastern Inner Mongolia combined with the geology of its neighboring areas. Studies show that during the Carboniferous-Permian in the eastern segment of the Tianshan-Hinggan Orogenic System, there was a giant ENE-NE-trending littoral-neritic to continental sedimentary basin, starting in the west from Ejinqi eastwards through southeastern Inner Mongolia into Jilin and Heilongjiang. The distribution of the Lower Carboniferous in the vast area is sparse. The Late Carboniferous or Permian volcanic-sedimentary rocks always unconformably overlie the Devonian or older units. The Upper Carboniferous-Middle Permian is dominated by llttoral-neritic deposits and the Upper Permian, by continental deposits. The Late Carboniferous-Permian has no trace of subduction-collision orogeny, implying the basin gradually disappeared by shrinking and shallowing. In addition, it is of interest to note that the Ondor Sum and Hegenshan ophiolitic melanges were formed in the pre-Late Silurian and pre-Late Devonian respectively, and the Solonker ophiolitic melange formed in the pre-Late Carboniferous. All the evidence indicates that the eastern segment of the Paleo-Asian Ocean had closed before the Late Carboniferous, and most likely before the latest Devonian (Famennian). 展开更多
关键词 CARBONIFEROUS-PERMIAN stratigraphic sequences southeastern inner mongolia Paleo-Asian Ocean
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A New Species of Cathayornis from the Lower Cretaceous of Inner Mongolia,China and Its Stratigraphic Significance 被引量:11
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作者 LI Jianjun LI Zhiheng +4 位作者 ZHANG Yuguang ZHOU Zhonghe BAI Zhiqiang ZHANG Lifu BA Tuya 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第6期1115-1123,共9页
An incomplete postcranial avian skeleton is described from the Lower Cretaceous Jingchuan Formation of Otog Banner of western Inner Mongolia and referred to a new species of Cathayornis, C. chabuensis sp. nov. This is... An incomplete postcranial avian skeleton is described from the Lower Cretaceous Jingchuan Formation of Otog Banner of western Inner Mongolia and referred to a new species of Cathayornis, C. chabuensis sp. nov. This is the first report of a Cathayornis from outside Liaoning Province. The new discovery indicates that Cathayornis coexisted with Otogornis genghisi, and a more detailed comparison between these two enantiornithine genera shows that Otogornis represents a more primitive genus than Cathayornis. Our analyses further indicate that Cathayornis is an arboreal bird. The discovery of a Cathayornis from this region also confirms that the avian fossil-bearing Jingchuan Formation is comparable to the Jiufotang Formation of the upper Jehol Group in western Liaoning, and should be referred to the middle-late Early Cretaceous. 展开更多
关键词 Cathayornis STRATIGRAPHY Lower Cretaceous Otog Banner inner mongolia
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Sporopollen Assemblages from the Cretaceous Yimin Formation of the Hailar Basin,Inner Mongolia,China 被引量:11
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作者 WAN Chuanbiao QIAO Xiuyun +5 位作者 XU Yanbin SUN Yuewu REN Yanguang JIN Yudong GAO Ping LIU Tongyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第4期459-470,共12页
Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are (in ascending order): the lmpardecispora-Aequitriradites- ... Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are (in ascending order): the lmpardecispora-Aequitriradites- Clawttipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites- Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data. 展开更多
关键词 CRETACEOUS Barremian-Early Albian sporopollen assemblage ANGIOSPERMS Hailar Basin inner mongolia
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A New Protoceratopsid (Dinosauria: Neoceratopsia) from the Late Cretaceous of Inner Mongolia, China 被引量:8
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作者 YOUHailu DONGZhiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第3期299-303,共5页
An almost complete skull, which was collected from the Upper Cretaceous of the Bayan Mandahu area in Inner Mongolia, China by the Sino-Canadian Dinosaur Project, is described and assigned to a new genus of protocerato... An almost complete skull, which was collected from the Upper Cretaceous of the Bayan Mandahu area in Inner Mongolia, China by the Sino-Canadian Dinosaur Project, is described and assigned to a new genus of protoceratopsid dinosaur, Magnirostris dodsoni gen. et sp. nov. This new taxon is distinguished from other protoceratopsids by the robust rostral bone and the existence of incipient orbital horn cores. The existence of an additional antorbital fenestra indicates a close relationship between Magnirostris and Bagaceratops. 展开更多
关键词 DINOSAURIA Neoceratopsia Late Cretaceous Bayan Mandahu inner mongolia China
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Ginkgo Huolinhensis sp.nov.from the Lower Cretaceous of Huolinhe Coal Field,Inner Mongolia,China 被引量:9
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作者 DONG Man SUN Ge 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期11-19,共9页
A new species, Ginkgo huolinhensis sp. nov., with well-preserved cuticle from the Lower Cretaceous, Huolinhe Formation of Huolinhe Coal Field in Inner Mongolia, China, was studied morphologically and anatomically. The... A new species, Ginkgo huolinhensis sp. nov., with well-preserved cuticle from the Lower Cretaceous, Huolinhe Formation of Huolinhe Coal Field in Inner Mongolia, China, was studied morphologically and anatomically. The main characters of the new species are found in the leaves which are deeply dissected with narrow lobes, trichomes developed on both upper and lower epidermal cells, a media papilla developed on the periclinal walls for each cell in upper cuticle, and no trichomes on the cuticle of the petioles. These characters of G. huolinhensis sp. nov. distinguish from the known species of Ginkgo previously reported. This study of the new species is beneficial for the taxonomic research of fossil Ginkgo, and should be helpful for a better understanding the paleoenvironment of Ginkgo living in northeastern China during the Early Cretaceous. 展开更多
关键词 new species GINKGO Early Cretaceous Huolinhe inner mongolia
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Environmental change inferred from Rb and Sr of lacustrine sediments in Huangqihai Lake,Inner Mongolia 被引量:11
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作者 CHEN Lei SHEN Hongyuan +4 位作者 JIA Yulian WU Jinglu LI Xusheng WEI Ling WANG Pengling 《Journal of Geographical Sciences》 SCIE CSCD 2008年第3期373-384,共12页
Based on the geochemical elements Rb and Sr in sediments with three different grain size fractions from profile H3 on the northern lacustrine bottomland 13 m above the Huangqihai Lake surface in 1986,the paper investi... Based on the geochemical elements Rb and Sr in sediments with three different grain size fractions from profile H3 on the northern lacustrine bottomland 13 m above the Huangqihai Lake surface in 1986,the paper investigates the record of palaeolake stand state, sedimentary environmental evolution,and winter monsoon change.First,these samples are separated into three different grain size fractions,i.e.,total sediments,77-20μm and〈20μm. Second,the chemical elements-Rb and Sr-of the grain size separation were tested and analyzed systematically in this paper.Then the elements compositions of these samples are measured using VP-320 mode fluorescence spectrum instrument,respectively.The magnetic susceptibility of these samples is measured using Kappabridge KLY-3 mode instrument made in Czech AGICO Company.The results showed the elements and the ratios varied regularly with the grain size.But the ratio of Rb/Sr in the sediments〈20μm correlates positively with the magnetic susceptibility of these samples.Therefore,the ratio of Rb/Sr in the fraction〈20 μm from the lake sediments reflected the strengthening of the weathering in the deposition sites.It is a good indicator of the summer monsoon-induced weathering and pedogenesis fluctuations and can be used to reconstruct the conditions of the paleoclimate and paleoenvironment. 展开更多
关键词 inner mongolia Huangqihai Lake HOLOCENE different grain size fractions lake sediment Rb/Sr ratio climatic change
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Spinel + quartz-bearing ultrahigh-temperature granulites from Xumayao,Inner Mongolia Suture Zone,North China Craton:Petrology,phase equilibria and counterclockwise p-T path 被引量:8
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作者 Huatian Zhang Jianghai Li +3 位作者 Shoujie Liu Wenshan Li M. Santosh Honghao Wang 《Geoscience Frontiers》 SCIE CAS 2012年第5期603-611,共9页
The Khondalite Belt within the Inner Mongolia Suture Zone (IMSZ) in the North China Craton is a classic example for Paleoproterozoic ultrahigh-temperature (UHT) metamorphism. Here we report new spinel-bearing meta... The Khondalite Belt within the Inner Mongolia Suture Zone (IMSZ) in the North China Craton is a classic example for Paleoproterozoic ultrahigh-temperature (UHT) metamorphism. Here we report new spinel-bearing metapelitic granulites from a new locality at Xumayao within the southern domain of the IMSZ. Petrological studies and thermodynamic modeling of the spinel -- quartz-bearing assemblage shows that these rocks experienced extreme metamorphism at UHT conditions. Spinel occurs in two textural settings:(1) high Xzn(Zn/(Mg + FeH -- Zn) = 0.071--0.232) spinel with perthitic K-feld- spar, sillimanite and quartz in the rock matrix; and (2)low Xzn (0.045-0.070) spinel as inclusions within garnet porphyroblasts in association with quartz and sillimanite. Our phase equilibria modeling indicates two main stages during the metamorphic evolution of these rocks:(l) near-isobaric cooling from 975 ℃ to 875 ℃ around 8 kbar, represented by the formation of garnet porphyroblasts from spinel and quartz; and(2)cooling and decompression from 850 ℃, 8 kbar to below 750 ℃- 6.5 kbar, represented by the break-down of garnet. The spinel + quartz assemblage is considered to have been stable at peak metamorphism, formed through the break-down of cordierite, indi- caring a near isothermal compression process. Our study confirms the regional extent of UHT metamor- phism within the IMSZ associated with the Paleoproterozoic subduction-collision process. 展开更多
关键词 Ultrahigh-temperaturemetamorphism PETROLOGY p-T path inner mongolia SutureZone North China Craton
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LA-ICPMS Zircon U-Pb Dating in the Jurassic Daohugou Beds and Correlative Strata in Ningcheng of Inner Mongolia 被引量:7
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作者 LIU Yanxue LIU Yongqing ZHANG Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第5期733-742,共10页
LA-ICPMS Zircon U-Pb dating is applied to volcanic rocks overlying and underlying the Salamander-bearing bed in the Daohugou beds of Ningcheng in Inner Mongola and Reshuichang of Lingyuan and Mazhangzi of Jianping in ... LA-ICPMS Zircon U-Pb dating is applied to volcanic rocks overlying and underlying the Salamander-bearing bed in the Daohugou beds of Ningcheng in Inner Mongola and Reshuichang of Lingyuan and Mazhangzi of Jianping in western Liaoning. The results indicate that the youngest age of the rocks in Daohugou of Ningcheng is 158 Ma, and the oldest one is 164 Ma. Synthesized researches indicate that the salamander-bearing beds in Daohugou of Ningcheng, Reshuichang of Lingyuan and Mazhangzi of Jianping were developed in the same period. The Daohugou beds were formed in the geological age of 164-158 Ma of the middle-late Jurassic. Whilst, the Daohugou beds and its corrdative strata should correspond to the Tiaojishan Formation (or Lanqi Formation) of the middle Jurassic in northern Hebei Province and western Liaoning Province, based on the disconformity between the Daohugou beds and its overlaying beds of the Tuchengzi Formation of Late Jurassic and the Jehol Beds of early Cretaceous, and the disconformity between the Daohugou Beds and its underlying Jiulongshan Formation, which is composed of conglomerate, sandstone, shale with coal and thin coal beds. 展开更多
关键词 inner mongolia Liaoning Daohugou Beds Zircon U-Pb dating LA-ICPMS Tiaojishan Formation JURASSIC
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LA-ICP-MS Zircon U-Pb Geochronology of the Fine-grained Granite and Molybdenite Re-Os Dating in the Wurinitu Molybdenum Deposit,Inner Mongolia,China 被引量:10
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作者 Cui LIU Jinfu DENG +4 位作者 Weiqiong KONG Liquan XU Guochun ZHAO Zhaohua LUO Ning LI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第5期1057-1066,共10页
The Wurinitu molybdenum deposit,located in Honggor,Sonid Left Banner of Inner Mongolia,China,is recently discovered and is considered to be associated with a concealed fine-grained granite impregnated with molybdenite... The Wurinitu molybdenum deposit,located in Honggor,Sonid Left Banner of Inner Mongolia,China,is recently discovered and is considered to be associated with a concealed fine-grained granite impregnated with molybdenite.The wall rocks are composed of Variscan porphyritic-like biotite granite and the Lower Ordovician Wubin'aobao Formation.LA-ICP-MS zircon U-Pb dating of the fine-grained granite reveals two stages of zircons,one were formed at 181.7±7.4 Ma and the other at 133.6±3.3 Ma.The latter age is believed to be the formation age of the fine-grained granite,while the former may reflect the age of inherited zircons,based on the morphological study of the zircon and regional geological setting.The Re-Os model age of molybdenite is 142.2±2.5 Ma,which is older than the diagenetic age of the fine-grained granite.Therefore the authors believe that the metallogenic age of the Wurinitu molybdenum deposit should be nearly 133.6±3.3 Ma or slightly later,i.e.,Early Cretaceous.Combined with regional geological background research,it is speculated that the molybdenum deposits were formed at the late Yanshanian orogenic cycle in the Hingganling-Mongolian orogenic belt,belonging to the relaxation epoch posterior to the compression and was associated with the closure of the Mongolia-Okhotsk Sea. 展开更多
关键词 fine-grained granite LA-ICP-MS zircon U-Pb geochronology molybdenite Re-Os dating Wurinitu molybdenum deposit inner mongolia
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