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Science China Earth Sciences 2008年第8期51卷 1099-1106页

作者： CAI QiuFang LIU Yu SONG HuiMing SUN JunYan The State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710075China School of Human Settlements and Civil Engineering of Xi’an Jiaotong University Xi’an 710049China

Long-time series of high-resolution temperature record from Chinese Loess Plateau is rare. An April-September mean temperature reconstruction (1826-2004) has been developed for the north-central shaanxi Province, China, based on tree-ring width analysis. The reconstruction captures 39.3% (p<0.001) of the variance in the instrumental data over the calibration period from 1951 to 2002. The reconstruction shows a high temperature period of 1928-1933, which coincides with the timing of the extreme drought event in 1920s in the entire northern China. The two low temperature periods in reconstruction are 1883-1888 and 1938-1942. With the global warming, the April-September mean temperature in study area has also increased since the 1970s, but has not exceeded the temperature in 1928-1933. Besides the statistical analysis, the reconstruction is also verified by the local dryness/wetness index and other dendroclimatological results.

关键词： Huanglong Mountain shaanxi Pinus tabulaeformis tree-ring width April-September mean temperature

Optimal livelihood strategy for different poverty groups among farmers: a case study of the Qin-Ba Mountain area in South-shaanxi, China

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Journal of Mountain Science 2020年第5期17卷 1206-1220页

作者： SU Fang YIN Ya-juan School of Economics and Management Shaanxi University of Science&TechnologyXi'an 710021China

Achieving sustainable livelihood is the ultimate goal of poverty alleviation efforts in mountainous areas,and selecting an optimal livelihood strategy for different poverty-type farmers greatly improves farmers’livelihood capital,resists livelihood risks,and promotes sustainable *** farmers,optimal livelihood strategy means better employment opportunities,higher family income(or better income structure),and stronger employability or development *** paper classifies different types of farmers’poverty on the basis of a quantitative evaluation of farmers’livelihood capital in the Qin-ba Mountain Area in South-shaanxi by using the k-means clustering method and subsequently the fuzzy evaluation method to evaluate the effectiveness of farmers’livelihood ***,the multi-attribute decision-making model is used to analyze the selection of optimal livelihood strategies for different poverty-type *** results suggest a significant difference in the selection of the optimal livelihood strategy for different poverty-type *** without financial and human capital choose to"go out to work,"farmers lacking natural capital choose to"acquire social insurance and government relief,"farmers without physical capital choose to"use loans,"and farmers lacking social capital choose to"use savings."Studying the selection of optimal livelihood strategies for different poverty-type farmers can help to propose targeted sustainable livelihood optimization programs for farmers and accelerate efforts to overcome poverty in mountainous areas.

关键词： Optimal strategy Livelihood capital Effectiveness evaluation Qin-Ba Mountain Area shaanxi

An Important Ornithischian Tracksite in the Early Jurassic of the Shenmu Region,shaanxi,China

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 1-10页

作者： LI Jianjun Martin G.LOCKLEY ZHANG Yuguang HU Songmei MATSUKAWA Masaki BAI Zhiqiang Beijing Museum of Natural History Beijing 100050China Dinosaur Tracks Museum CB 172University of Colorado at DenverColorado80217-3364 USA Archaeological Research Institute of shaanxi Province Xi'anShaanxi 710054China Department of Environmental Sciences Tokyo Gakugei UniversityKoganeiTokyo 184-8501Japan School of Earth and Space Sciences Peking UniversityBeo'ing 100871China

A large track site with multiple, well-preserved trackways of an Early Jurassic quadrupedal ornithischian dinosaur is the first report of Moyenisauripus-like trackways from Asia, herein named Shenmuichnus youngteilhardorum. The tracks occur in a clastic fluvial sequence in the Fuxian Formation in Shenmu County, shaanxi Province, which is in the same general region as the discovery site of Sinoichnites, the first dinosaur track reported from China. Based on size and morphology, it is likely that Sinoichnites, which is now lost, also represents an ornithischian. The Shenmuichnus youngteilhardorum trackways show two modes of preservation： the first representing deeper tracks, with sediment rims, results in Deltapodus-like tracks, with indistinct pes digit traces and sub-circular manus traces, the second produces Moyenosauripus-like tracks, with clear tridactyl and pentadactyl digit traces in the pes and manus respectively. Thus the Shenmu trackways play a key role in resolving globally significant ichnotaxonomic problems surrounding the nomenclature of Sinoichnites, Moyenosauripus, Deltapodus and other named （Ravatichnus） and unnamed trackways from Asia, Africa and Europe. In addition they shed important light on the paleogeographical and paleoecological distribution of quadrupedal ornithischians in the Early Mesozoic. The track site has been the focus of a major excavation to transfer the trackways from their original remote location to the new Shenmu Museum, in Shenmu City. Other tracksites in the area which reveal Anomoepus, Grallator and the Deltapodus morphotype, together with Shenmuichnus and plant fossil evidence, suggest an Early Jurassic age for the tracksite.

关键词： dinosaur tracks Early Jurasic Shenmu shaanxi

Factors Controlling Precipitation of Barite and Witherite and Genesis of the Ankang-Xunyang Barium Deposits,shaanxi,China

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Acta Geologica Sinica(English Edition) 2015年第3期89卷 836-851页

作者： WU Shenghua LIU Jiajun ZHAI Degao State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Institute of Mineral Resources Chinese Academy of Geological Sciences

The barium deposits in Ankang and Xunyang counties,shaanxi Province,China,occur in the northernmost part of the world-class barium metallogenic belt in south *** deposits are hosted by the Lower Silurian carbonaceous siliceous rocks,with a unique combination of barite and *** homogenization temperatures of fluid inclusions in the barite are mainly concentrated between 135 and 155 ℃,whereas those from the witherite have two peaks of 165-175 ℃,and 215-225℃,*** Raman analysis of fluid inclusions indicates that the vapor phase of fluid inclusions in barite is dominated by H_2O,although some contains N_2,H_2S,and CH_*** compositions of the vapor and liquid phases of fluid inclusions in witherite can be divided into two end-members,one dominated by H_2O without other volatiles,and the other containing CH_4,C_2H_6,C_3H_8,C_2H_4,and C_6H_6 in addition to H_***_2,H_2S,and some CH_4 are interpreted as products of chemical reactions during *** gases（CH_4,C_2H_6,C_3H_8,C_2H_4,and C_6H_6） in the fluids were critical in the formation of barium sulfate versus *** δ^（34）S values of barite range from 38.26‰ to54.23‰（CDT）,the δ^（34）S values of sulfides coexisting with barium minerals vary from 22.44‰ to25.11‰（CDT）,and those in the wall rock from 11.60‰ to 19.06‰（CDT）.We propose that the SO_4^（2-）generally experienced bacterial sulfate reduction in seawater before mineralization,and some SO_4^（2-）also experienced thermochemical sulfate reduction in hydrothermal system during *** δ^（13）C values of witherite range from-27.30‰ to-11.80‰（PDB）,suggesting that carbon was sourced from organic substances（like CH_4,C_2H_4,and C_2H_6）.The formation of witherite was possibly associated with thermochemical sulfate reduction,which caused the consumption of the organic gases and SO_4^（2-） in the hydrothermal solutions,consequently inhibiting barite *** important conditions for forming witherite include high f

关键词： barium deposits fluid inclusions S C and 0 isotopic compositions thermochemicalsulfate reduction Ankang and Xunyang counties shaanxi

Skeletal faunas from the Qiongzhusian of southern shaanxi: biodiversity and lithofacies-biofacies links in the Lower Cambrian carbonate settings

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Progress in Natural Science:Materials International 2004年第1期14卷 92-97页

作者： Michael STEINER 13355 Berlin Ackerstrasse 71～76 Germany Technische Universitt Berlin Sekr.ACK 14

The Xiaoyang section, located in Zhenba County of shaanxi Province, is important both for documenting the biodiversity of the Qiongzhusian Stage (Lower Cambrian) and for analyzing lithofacies biofacies links in carbonate depositing environments on the Yangtze Platform. The skeletal fossils from the Xihaoping Member, including linguloid valves, cambroclavid and chancelloriid sclerites, genal and occipital spines of polymerid trilobites, and tubular fossils, are described here as the Eoobolus Cambroclavus fauna, which mainly occurred in peritidal environments. The fossils from the argillaceous limestones of the lower Shuijingtuo Formation, containing lingulate brachiopods, eodiscoid trilobites, bivalved arthropods, microdictyoniid sclerites and siliceous sponge spicules, are regarded as the Palaeobolus Hupeidiscus Kunmingella fauna, which presumably lived in subtidal or deeper water environments. The faunal diversity in the Xihaoping Member is lower than that in the lower Shuijingtuo Formation. The investigations of the skeletal fossil assemblages from carbonate lithofacies in southern shaanxi will significantly contribute to a detailed documentation of the biodiversity during the Qiongzhusian interval on the Yangtze Platform and add new knowledge on the Cambrian bioradiation.

关键词： skeletal fauna Xihaoping Member Shuijingtuo Formation Lower Cambrian shaanxi

Discovery and significance of microfossils from Qinbaikouian Dazhuang Formation in Luonan, shaanxi Province

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Chinese Science Bulletin 1997年第3期42卷 243-245页

作者： Chen, Z Hua, H Jian, WC Hu, YX Department of Geology Northwest University Xi’an China Xi’an Institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Xi’an China

THE microfossils were obtained by using 5%—7% HF acid from Qingbaikouian Dazhuang Formation in Luonan County, shaanxi Province, with an age of 800—1000 Ma. The fossils may be one type of the oldest skeletal mierofos... 详细信息

关键词： microfossil Qinbaikouian Dazhuang Formation shaanxi Province.

Discovery of micromammalian fauna of Sichuan-Guizhou Area in Lantian, shaanxi

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Chinese Science Bulletin 1998年第4期43卷 336-339页

作者： Li Chuanling Xue Xiangxu NW Univ Xian Dept Geol Inst Cenozoic Geol & Environm Xian 710069 Peoples R China

The study of the Xishuidong micromammalian fauna, found from Lantian, shaanxi Province, indicates that both the northern slope of the Qinling Mountains and Sichuan_Guizhou area must belong to the same Oriental Realm in middle_late Middle Pleistocene. The age of the Xishuidong fauna should be later than that of the Gongwangling fauna, and even a little later than that of the Zhongjiawo fauna in age. The fauna is related not only to that of layers 9 and 8 of Peking Man Locality in northern China, but also to the micromammals from Hexian Man Locality in southern China.

关键词： Sichuan_Guizhou Area Lantian of shaanxi micromammalian fauna Middle Pleistocene.

Geochemical Characteristics and Sources of Ore-forming Fluids of the Mayuan Pb-Zn Deposit,Nanzheng,shaanxi,China

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Acta Geologica Sinica(English Edition) 2015年第3期89卷 783-793页

作者： LIU Shuwen LI Ronxi CHI Guoxiang ZENG Rong LIU Lingfang SHI Shun Chang'an University Key Laboratory for the study of Focused Magmatism and Giant Ore Deposits MLR University of Regina Geophysical and Geochemical Exploration Corporation of Northwest Geological Exploration and Mining Bureau for Nonferrous Metals

The Mayuan stratabound Pb-Zn deposit in Nanzheng,shaanxi Province,is located in the northern margin of the Yangtze Plate,in the southern margin of the Beiba *** orebodies are stratiform and hosted in breciated dolostone of the Sinian Dengying *** ore minerals are primarily sphalerite and galena,and the gangue minerals comprise of dolomite,quartz,barite,calcite and solid *** inclusions from ore-stage quartz and calcite have homogenization tempreatures from 98 to 337℃ and salinities from 7.7 wt%to 22.2 wt%（NaCl equiv.）.The vapor phase of the inclusions is mainly composed of CH_4 with minor CO_2 and H_*** δD_（fluid） values of fluid inclusions in quartz and calcite display a range from-68‰ to-113‰（SMOW）,and the δ^（18）O_（fluid）values calculated from δ^（18）O_（quartz） and δ^（18）O_（calcite） values range from 4.5‰ to 16.7‰（SMOW）.These data suggest that the ore-forming fluids may have been derived from evaporitic sea water that had reacted with organic *** δ^（13）C_（CH4） values of CH_4 in fluid inclusions range from-37.2‰ to-21.0‰（PDB）,suggesting that the CH_4 in the ore-forming fluids was mainly derived from organic ***,together with the abundance of solid bitumen in the ores,suggest that organic matter played an important role in mineralization,and that the thermochemical sulfate reduction（TSR） was the main mechanism of sulfide *** Mayuan Pb-Zn deposit is a carbonate-hosted epigenetic deposit that may be classified as a Mississippi Valley type（MVT） deposit.

关键词： fluid inclusion ore-forming fluids organic matter Mayuan Pb-Zn deposit shaanxi

Biological records of paleoclimate and paleoenvironment changes from Guanzhong area, shaanxi Province during the last glacial maximum

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Chinese Science Bulletin 2000年第9期45卷 853-857页

作者： J.Head A.J.T.Jull State Key Laboratory of Loess and Quaternary Geology Xi'an 710054ChinaNSF-AMS Facility Department of PhysicsUniversity of ArizonaAZ 85721USA

We have collected a suite of Paleoloxodon naumanni-Coelodonta antiquitatis fossils from a river terrace profile between Xi’an and Xianyang cities in Guanzhong Area, shaanxi Province. A detailed examination of the fossils, together with 14C determinations and pollen analyses, have enabled us to reconstruct preliminary features of climate and environment changes and their evolutionary processes, within the last glacial maximum (LGM): about 20 ka ago, the climate was basically cool and wet, and was favourable for the existence of Paleoloxodon naumanni-Coelodonta antiquitatis fauna. This was followed by a cold, dry phase which was no longer suitable for this type of faunal suite, causing the death of a large number of mammalian assemblages. The available evidence indicates the existence of cold-dry and cool-wet climate and environment fluctuations during the LGM. The cool-wet stage within the LGM reflects a Heinrich event occurring in the high latitude areas, proving the existence of a teleconnection

关键词： Guanzhong of shaanxi Province Paleoloxodon naumanni-Coelodonta antiguitatis fauna last glacial maximum paleomonsoon precipitation.

Formation of the Devonian Fengtai Hydrothermal Brine Basin and the Metallogeny of Gold and Lead-Zinc Mineralizations in shaanxi

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Acta Geologica Sinica(English Edition) 2000年第3期74卷 500-503页

作者： ZHU Huaping GUO Jian LIU Ping LI Falin HUANG Changqing Northwest Exploration Bureau of Geology State Bureau of Nonferrous Metals IndustryXi’an 710054

The study of the relationships between the hydrothermal sedimentary formations and the gold and lead-zinc mineralizations in the Devonian Fengtai basin in shaanxi shows that there was a hydrothermal brine sedimentary event which was inserted into the normal sedimentary background from the late Middle Devonian to the early Late Devonian. This event is closely related to gold and lead-zinc mineralizations in this area.

关键词： hydrothermal sedimentary formation gold and lead-zinc mineralizations Devonian Fengtai basin shaanxi