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Chemistry of Aerosols over Chukchi Sea and Bering Sea 总被引：2，自引：0，他引：2
The contents of elements in aerosols sampled during the First Chinese Arctic Research Expedition (CHINARE-1) show great differences from one element to another. Na, K,Ca, Mg, A1, F, and Cl are the major components in the aerosols, whose contents are larger than 30 ng/m^3. The chemical elements whose contents vary between 0.1 - 30 ng/m^3 are Br,Sr, Cr, Ni, and Zn. The chemical elements whose contents are close to or slightly higher than 0.1 ng/m^3 are Rb, Ba, Zr, Th, and Pb. The contents of As, Sb, W, Mo, Au, La, Ce, Nd,Sin, Eu, Tb, Yb, Lu, Sc, Co, Hf, Ta, and Cd are less than 0.1 ng/m^3. The mass concentration data for the same element, as observed during CHINARE-1, are almost accordant, but much lower than what is observed in the China‘ s seas or the coasts of China. The enrichment factor and electron microscopic analyses and lead isotope tracing were used to distinguish their sources.Four groups of sources can be classified as follows: anthropogenic: As, Sb, W, F, Mo, Au,Cu, Pb, Cd, V; crustal: La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Fe, Sc, Cr, Co, Ba, Zr, Hf,Ta, Cs, Mn, Th, U; oceanic:Na, K, Ca, and Mg; and mixing: Rb, Sr, Ca, and Mg. 相似文献
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本文对河南济源盆地大峪槐疙瘩岭二叠系上石盒子组(P3sh)、孙家沟组(P3s)和三叠系刘家沟组(T1l)剖面岩石样品进行了元素、频率磁化率、碳酸盐以及总有机质等的分析研究,结果表明在二叠系孙家沟组(P3s)底部济源动物群化石层、以及三叠系刘家沟组(T1l)底部界线(P/T)附近,其微量和常量元素发生了较明显的变化。化石层中Ba,Cr,Hf,Nb,Th,Ti,V,Y,Tl,Zn,Cu,Ga,Pb,Ni,La,Rb,Nd,以及K2O,Al2O3,Fe2O3含量相对较高,Zr,W,Sr,Bi,Co,Ce,以及SiO2,Na2O含量较低,MgO,CaO,Mn则没有明显的变化。Ba,Hf,Nb,Th,Ti,V,Y,W,K2O,Al2O3,SiO2,Na2O,Bi,Fe2O3,Ni,Co,La,Nd,Ce,及有机碳含量在三叠系底部含量明显上升,Cu,Ga,Pb,Tl,Zn,Cr,Zr,Sr,MgO,CaO,以及岩石频率磁化率Xfd、碳酸盐含量则明显下降。该剖面不仅记录了二叠—三叠纪的生物灭绝事件,而且有明显的二叠—三叠系界线,事件及界线的形成可能与沉积环境和古气候有关,水体的变浅、炎热气候和风化作用加强可能是直接的原因。石盒子组(P3sh)主要为河流—三角洲沉积环境,古气候相对温暖湿润;孙家沟组(P3s)为三角洲平原相,前期和后期有强烈风化作用,并且炎热多雨。中期则水平面上升,水下三角洲前缘砂质沉积为主;三叠系刘家沟组(T1l)则水体进一步扩张,气温相对下降。 相似文献
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《Scientia Geologica Sinica》1999,(1)
1.IntroductionForelandbasin,thesedimentarybasinlyingbetweenthefrontofanorogenandtheadjacentcraton,isanimportantaspectforthestudyonlithospheretectonicevolutionoforogen(e.g.,Tankard,1986,Ren,etal.,1991;Li,1992,Chen,etal.,1992,Liu,etal.,1994,LihouandAlien,1996,Li,etal.,1997,DongandZhang,1997).Currently,itisdividedintotwogenetictoes,i.e.,peripheralforelandbasinsituatedagainsttheouterarcoftheorogenduringcontinent-continentcollisionandretro-arcforelandbasinbehindamagmaticarclinkedwithsubductiono… 相似文献
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中國礦産賦藏,原非少數,其重要者如煤,鐵,石油,錳,鎢,銻,鉛,鋅,錫,金,鋁以及其他金屬非金屬等,多所發现。然其價值之詳細認識,则尚未敢遽言。近年經地質調查所之努力進行,關於重要礦藏量之估計,多有增進,茲就已得部份列如第一表。計有煤,鐵,石油,鎢,銻,鋁,螢石及菱鎂礦等。 相似文献
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《Scientia Geologica Sinica》1999,(3)
1.IntroductionTheChineseAltaidorogenicbeltislocatedinnorthemXinjiang,ChinaandisthemiddleportionofamoreextensiveorogeninthecentralAsia,namedAltaidorogen,whichextendsfromwesternMongolia,throughnorthwesternChina,toeastemKazakhstan.IntermsofitsstratigraPhy,magmatism,metamorphismandsmictufalpattems,theChineseAltaidorogenicbeltcanreflectsthegeodynamicevolutionofthewholeAltaidorogen.BasedonthegeologicalfeaturesoftheChineseA1taidorogenicbelt,amodelofgeodynamicevolution,calledaccretionaryarcoroge… 相似文献
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《Continental Dynamics》1997,(1)
ForaPrecambriancratoncomposedofcompositeterranes,orblocks,andbelts,whichexperiencedcomplexpolyphasedeformationandmetamorphism,thefinaltectonothermaleventismoresignificantthantheearlieronesinthelightofplatetectonics,becausethefinaltectonothermaleventresultedfromamalga-mationofthecraton.Although,generally,aworkinghypothesisofpolyphasedeformationandmetamorphismiswidelyappliedtoahigh-gradeterrane,dis-cernmentofitsfinaltectonothermalepisodeisvitaltounderstandingitsgeologicalhistory.Inrecentyears,an… 相似文献
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《地下水科学与工程》2021,(1)
正Aims and Scope Journal of Groundwater Science and Engineering aims to be an innovative,high-impact and authoritative academic journal for researchers across the hydrogeology,environmental geology,engineering geology,ecology and environment community.It mainly reports the latest and most important achievements in cutting-edge and emerging topics,as well as the traditional topics referring to new methodology,technology,applications and theoretical research in groundwater science and engineering.Papers published involve various aspects of research concerning groundwater,such as hydrogeology,environmental geology,engineering geology,urban geology,climate change,environmental change,ecology,water cycle,water resources,geochemistry,geothermy,agriculture,groundwater development and utilization,groundwater pollution,and research with supporting disciplines:Geophysics,geobiology,mathematics,numerical modeling,economics, 相似文献
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一.热液硫化矿床的一些分散元素热液矿床包括多数最重要的金属矿床,如Cu,Pb,Zn,Ag,Sb,Hg,Mo,W,U,Au等。除最后三种元素外,其余都以硫化物为主要存在方式。这些硫化矿物,除含上列元素外,还常常含有一些稀少的元素,如Cd,Ga,In,Tl,Gl,Re,Se,Te等,后者的含量和硫化物中 相似文献
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Chris King 《Geology Today》2020,36(3):96-100
The spread of the 2020 Covid-19 pandemic has had a major effect on the way that geologists carry out their work—and particularly those engaged in educating the next generation of geologists. There are a number of resources available, and some, focussed on fostering interest in budding geologists, are presented here. 相似文献
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Tristram R. Kidder 《Engineering Geology》1996,45(1-4):305-323
The impact of Harold N. Fisk's work on the archaeology and geoarchaeology of the Lower Mississippi Valley (LMV) has been monumental. As a result of his landmark publications on the geology of the alluvial valley of the Mississippi River our comprehension of the interplay between geological, geomorphic, and human actions is relatively well developed. However, geologists and archaeologists still need to work together more closely to appreciate and understand the contributions each field has to offer. Examination of the interplay between geologists and archaeologists in the realm of dating and landscape evolution provides the basis for an investigation of the state of geoarchaeology in the LMV today. Integration of research demands an appreciation of scale which must be approached from an historical perspective. Humans have, both in the past and the present, impacted the natural environment of the Mississippi River and its floodplain. Only when this fact is fully appreciated by archaeologists and geologists alike will it be possible to forge a new synthesis of the relationship between the dynamic alluvial valley and its human occupants. 相似文献
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岩层厚度的计算是野外地质工作内业整理和地质分析中的一项经常性工作，传统的工作方法往往要花费地质人员大量的时间和精力。利用EXCEL电子表格中的函数关系，通过编辑公式进行岩层厚度的计算，从而能正确、简单、快捷地完成此项工作，大大地提高野外地质人员的内业整理工作效益。 相似文献
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NIGEL H. WOODCOCK 《Geology Today》1993,9(4):142-147
Most professional geologists are employed to find oil, gas and coal. They work for a society constantly concerned about future supplies of fossil fuels. Yet now the global atmospheric pollution from burning these fuels threatens to harm society sooner than any shortage of resources. Caught amidst the fossil fuel debate, how should geologists respond? 相似文献
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Edward P. F. Rose 《Geology Today》2019,35(3):107-114
During the Second World War, the Allied invasion of the French coast of Normandy on D‐Day, 6 June 1944, was the greatest amphibious assault in world history. An article in Geology Today (v.11, for 1995, pp.58–63) marked the 50th anniversary of the end of the war in Europe, on 8 May 1945, by describing how British military geologists had participated in planning for D‐Day and in the NW Europe campaign that followed it. The work of these geologists provides a classic case history, revealing that ‘military geology’ has many potential applications. Geological factors influenced site selection for temporary airfields, predictions of trafficability for the Normandy beaches, the development of potable water supplies, and quarrying for road metal—and more besides. This new article helps to mark the 75th anniversary of D‐Day by further details of how geologists and geology contributed to Allied victory. 相似文献
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<正> 清理地层单位是一项涉及面广、法规性强的工作,必须要以先进的理论作指导,要有适合中国地层研究实际的法规性文件作依据。 《地质矿产部全国地层多重划分对比研究讨论会纪要》(1990)指出,清理地层单位时各单位要“认真学习《中国地层指南》和《国际地层指南》,掌握地层的多重划分、对比概念、 相似文献
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《International Geology Review》2012,54(5):842-844
The Interdepartmental Stratigraphic Committee records its response to the recommendations 1962. The Soviet geologists filed 23 papers for presentation at this conference but “there was a lack of the First International Colloquium on the Jurassic System, held in Luxemburg in August of representation of Soviet geologists” at the Colloquium, hence no argument of the Soviet case on many points. The paper presents a counter-classification for the Jurassic System and a compendium of 12 other decisions of Soviet geologists on the work of the colloquium.—B.N. Copper 相似文献
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浙江诸暨地区陈蔡群加里东期变质年龄的确认
及其地质意义 总被引：4，自引：0，他引：4
陈蔡群是浙东南地区重要的岩石单位之一,一直被认为是华夏地块变质基底的重要组成部分,20世纪众多地质学家对其开展过研究工作。选取浙江省诸暨市孝四地区的陈蔡群为研究对象,对其开展了详细的LA-ICP-MS同位素定年工作。锆石CL图像和微量元素特征显示其锆石均为变质锆石,17个分析点获得206Pb/238U年龄加权平均值435Ma±4Ma,属于加里东期,此年龄代表了诸暨地区陈蔡群的主变质年龄。结合华南已报道的高精度加里东期年龄纪录,探讨了华南加里东运动发生的时限和运动性质。研究结果表明,华南加里东运动主要发生于420～445Ma之间,435Ma为其一个峰值。 相似文献
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