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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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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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《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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在分析铁路隧道建设中常用的超前地质预报方法的基础上,通过地质调查对云南省某在建铁路隧道进行风险定级,并采用与风险等级相应的综合预报方案,准确地预报了该隧道潜在的地质灾害.根据预报结果及时调整了施工和应急方案,有效地预防了施工事故,减少了工程损失,保证了施工安全. 相似文献
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信息化设计施工是一种动态的设计施工方法,通过施工过程中的施工信息,掌握工程岩土体的工作状态,从而调整优化初始设计施工方案。本文分析了机场高填方边坡的主要施工信息,提出了信息化设计施工的工作模式,并以西南某机场扩建工程为例,介绍了机场高填方边坡信息化设计施工的实际工程应用。这种设计施工模式在实际工程中取得了较好的应用效果。 相似文献
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在沿海滩涂地带进行大型海堤建设,项目难度大,施工风险较高。为了使项目工程建设安全可靠地进行,必须开展施工期现场岩土监测工作。综合介绍省重点建设项目——福建大唐宁德电厂的海堤施工现场采用多种岩土监测手段,总结和分析各种监测成果,为工程建设提供可靠的科学依据。确保海堤施工顺利进展。 相似文献
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随着建筑市场的不断规范,以及各种配套法津法规日趋完善,隧道施工分工序承包组织模式是建筑企业发展的趋势。根据建设项目实行过程以及管理的现状,对隧道施工生产管理与控制进行分析,整理了一套相对合理的经验,使隧道施工分工序组织模式的管理得以推广。 相似文献