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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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土压缩模量预测回归分析方法 总被引：1，自引：0，他引：1
在土压缩模量Es的分析计算中,常用的分析方法是根据土的e-p曲线试验资料建立公式求解,本文引入了数学上的回归分析方法来探讨Es与其它各项物理力学指标参数之间的相关关系,旨在找出对Es影响最显著的指标参数,并建立最优回归方程式,以此来预测Es。研究结果表明:该方法通用性强,应用范围广,亦可推广应用于其它相关领域。 相似文献
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考虑核电厂地基-基础的动力相互作用,应用显式动力有限差分法分析了地震作用下极软岩、较软岩、坚硬岩上核电厂建筑结构基础的地震响应特征,比较了岩石坚硬程度对基础加速度反应谱的影响。研究表明：随着岩石坚硬程度的提高,核电厂建筑物结构基础的地震响应有增加的趋势;在周期轴上,基础处的加速度反应谱曲线会随着岩石坚硬程度的提高逐渐向短周期（高频段）方向移动。在高频段,建造于较坚硬岩石上基础结构的加速度反应谱值偏大;在中等频段,建造于较软岩石上基础结构的加速度反应谱值偏大;在低频段,岩石坚硬程度对加速度反应谱的影响不显著。 相似文献
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Ivan V. BRAGIN Georgy A. CHELNOKOV Oleg V. CHUDAEV Natalia A. KHARITONOVA Sergey V. VYSOTSKIY 《《地质学报》英文版》2016,90(1):276-284
Studied waters belong to warm(T=30-50℃),alkaline(pH=8.9-9.3),low mineralized(TDS235 mg/1)Na-HCO_3 or Na-SO_4-HCO_3 thermal waters with high content of SiO_2(up to 81 mg/l)and F(up to 3.9 mg/1),occur on modern volcano-tectonic rejuvenated areas of Eastern Sikhote-Alin orogenic belt.Low~3He concentration as well as N_2/O_2 and N_2/Ar ratios exclude influence of deep mantle fluid.New rare earth element data constrain our understandmg of water-rock interaction occurring in the water source region.Meteoric origin of waters is proved by stable isotope values varying from-71‰to-136.1‰and from-10.8‰to-18.8‰forδ~2U andδ~(18)O respectively.REE patterns reflect high pH,resultfing from water-rock interaction and oxidative conditions.Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1°C and 82.2-125.8℃respectively.Presence of deep faults both with abnormal thermal gradient(~45-50 K/km)define unique geochemical shape of thermal waters of Sikhote-Alin,area,where no present volcanic activity is registered. 相似文献
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Using the database of automatic hydrometeorological stations, installed in the Don RIver delta and Taganrog Bay seashore, the sources of the anomalois scale water negative surge and salinization of the Azov Sea under conditions of low river flow in 2015–2016 are studied. The new schemes of stratification and advection of salty sea waters in the Don River mouth under different weather conditions, water discharge and levels are given. 相似文献
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地震次生地质灾害风险评估集对态势分析 总被引：2，自引：0，他引：2
5．12四川汶川8级强震引发了大量次生地质灾害,加剧了灾情并严重影响抗震救灾。地震次生地质灾害受多重因素制约,其孕育与致灾过程具有不确定性。利用集对分析原理与方法,对地震次生地质灾害进行同异反态势分析,拟定了风险评估的集对分析同一度、差异度、对立度等指标体系的构建原则与赋值标准,对承灾体系统的不确定性及其作用作了刻画与分析,建立了不同风险分区代表性的集对分析联系度表达式,为地震灾害研究提供了可资借鉴的新思路和技术方法。 相似文献
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下扬子区三叠纪古地理演化 总被引：2，自引：2，他引：0
下扬子区在三叠纪期间接受了早-中三叠世海相碳酸盐沉积、中-晚三叠世海陆交互相和陆相湖沼沉积.沉积相带的空间分布和古地理格局的变迁明显地受到区域构造的控制.区内盆地发育与演化是在华南板块与扬子板块、扬子板块与华北板块相互作用的背景下进行的.早-中三叠世末期的印支运动是下扬子区构造-古地理格局改变的决定性因素,使下扬子海盆闭合,沉积类型由海相沉积变为陆相沉积.下扬子区三叠纪古地理的演化特征也为板块碰撞提供了沉积证据. 相似文献
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