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简介：TheauthorshavedetailedlyandsystematicallystudiedthecarbonisotopiccompositionofEarlyProterozoiccarbonaterocks.SampleswhicharealldolomicriteweretakenfromtheJianancun,DaguandongandHuaiyincunFormationsoftheHutuoGroupinWutaiCountyShanxiProvince,NorthChina.Atotalof209sampleswereanalysedfortheircarbonisotopecompositions,andthemeansamplingintervalwas6.9m.Carbonisotopeanalysisclearlyshowsδ13CshiftsattheboundarybetweentheJian’ancunFormationandDaguandongFormationandneartheboundarybetweentheDaguandongFormationandHuaiyincunFormation.LikecarbonisotopeshiftsattheCretaceous-Tertiary,Permian-TriassicandPrecambrian-Cambrianboundaries,thediscoveryofδ13CshiftsintheEarlyProterozoichasimportantsignificanceinfurtherstudiesonEarlyProterozoicbioticevolution,regionalandglobalstratigraphiccorrelation,andcarbongeochemicalcycles.

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简介：BasedonPb-Pbisochrondataofmorethan40Precambrianpolymetallicdeposits,theauthorsconsiderthattherearefourmineralizationperiodsforthePrecambriancopperdepositsinChina,andthemajorcopperdepositswereformedatabout1800Ma;therearethreemineralizationperiodsforgolddepositsformedfromArchaeantoProterozoic.BystudyinghundredsofleadisotopedatafromsomeMesozoiccontinentalsubvolcanicCuandAgpolymetallicdepositsandfine-disseminatedgolddeposits,theauthorsfoundthatthecalculationbasedontheleadsingle-stageevolutionmodelortwo-stageevolutionmodelcannotgivethetrueore-formingagesbutcanprovidemoreinformationaboutmineralizationandmaterialsourcesofthedeposits.

简介：Ananomalousisotopeeffectexistsinmanyheavyelementisotopesystems(e.g.,Sr,Gd,Zn,U).Thiseffectusedtobecalledthe‘‘odd–evenisotopeeffect’’becausetheoddmassnumberisotopesbehavedifferentlyfromtheevenmassnumberisotopes.Thismass-independentisotopefractionationdrivingforce,whichoriginatesfromthedifferenceintheground-stateelectronicenergiescausedbydifferencesinnuclearsizeandshape,iscurrentlydenotedasthenuclearfieldshifteffect(NFSE).ItisfoundthattheNFSEcandriveisotopefractionationofsomeheavyelements(e.g.,Hg,Tl,U)toanastonishingdegree,farmorethanthemagnitudecausedbytheconventionalmass-dependenteffect(MDE).Forlightelements,theMDEisthedominantfactorinisotopefractionation,whiletheNFSEisneglectable.Furthermore,theMDEandtheNFSEbothdecreaseastemperaturesincrease,thoughatdifferentrates.TheMDEdecreasesrapidlywithafactorof1/T2,whiletheNFSEdecreasesslowlywithafactorof1/T.Asaresult,evenathightemperatures,theNFSEisstillsignificantformanyheavyelementisotopesystems.Inthisreviewpaper,webeginwithanintroductionofthebasicconceptoftheNSFE,includingitshistoryandrecentprogress,andfollowwiththepotentialimplicationsoftheinclusionoftheNFSEintothekineticisotopefractionationeffect(KIE)andheavyisotopegeochronology.

简介：AnincreasingnumberofgeologistsinSouthAmericahaveturnedtheirattentiontoisotopegeologyasatoolinthewidercontextoftheEarthSciences.Asaresult,aseriesofsymposiaontheSouthAmericanisotopegeology(SSAGI)hasbeenorganizedeverytwoyearstoprovideanappropriateforumfordiscussionofmethodsandapplicationsofstableandradiogenicisotopes.

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简介：TheisotopeeffectsofablationprocessesinfusionplasmaforfivecombinationsofsolidisotopichydrogenicpelletsH2,HD,D2,DT,T2havebeenfirsttimestudied.Theresuitsshowthatthemodificationscausedbyisotopeeffectsforpelleterosionspeedsrangefrom1forhydrogenpelletdownto0.487fortritiumpelletandarenotnegligibleinablationratecalculations.Theseeffectsleadtodeepermassdepositionandimprovedcorefuelingefficiency.

简介：高纯净的N2被用来在离子交换树脂的离子纯化期间增加活动阶段流动率。这被执行改进同位素分离和纯化的效率，并且满足快速的multiple-collector-inductively联合的血浆团spectrometry(MC-ICPMS)的效率要求分析。为Cu同位素分离，我们的结果以煤气的流动率显示了那>60mL/min，色析法的山峰拓宽了的分离和恢复率减少了到<99.2%。在另一方面，在Cu山峰的重要变化都没以20mL/min的煤气的流动率被观察，恢复率决心是>99.9%。Cu同位素比率，由标准样品的括方法测量了，同意了在内的引用数据一???牡浡?????????祳据牡潢慮整???????????????ò作？？

简介：TheDajiangpingpyritedepositlocatedinthemiddlesectoroftheYunkaiupliftinwesternGuangdongisastratiformsulphidedepositoccurringinSinianmarineclasticandfineclasticrocks.Theformationofthedepositwasrelatedtosubmarineexhalationandhotbrinedeposition.Apartofitwasreformedbylate-stagehydrothermalsolution.Theδ34Svaluesofpyritevaryfrom-25.55‰to+21.07‰,whichareinverselyproportionaltothecontentoforganiccarboninoreandpyrite.Passingfromstripedfine-grainedpyriteoretomassivecoarse-grainedpyriteore,i.e.fromsouthtonorth,thesulphurisotopiccompositionchangesfromthelightsulphur-enrichedonetotheheavysulphur-enrichedone.Theleadisotopiccompositionofstripedoreisconsistentwiththatofthecountryrocksoforebodiesandtheleadisradiogenicleadderivedfromtheuppercrust.Theleadisotopiccompositionofmassiveoreisrelativelyhomogeneousandits206Pb/204Pb,207Pb/204Pband208Pb/204Pbratiosareabitlo

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简介：Oxygenisotopefractionationwasexperimentallystudiedinthequartz-wolframite-watersystemfrom200to420℃.ThestartingwolframitewassynthexizedinaqueoussolutionsofNa2WOR·2H2O+FeCl2·4H2OorMnCl2·4H2O.Thestartingsolutionsrangeinsalinityfrom0to10equivalentwt.%NaCl.Experimentswereconductedinagold-linedstainlesssteelautoclave,withfillingdegreesofabout50%.Theresultsshowednosignificantdifferenceindquilibriumisotopefractionationbetweenwaterandwolframite,ferberiteandhuebneriteatthesametemperature(310℃）.Theequilibriumoxygenisotopefractionationfactorsofwolframiteandwatertendtobeequalwithincreasingtemperatureabove370℃.buttoincreasesignificantlywithdecreasingtemperaturebelow370℃.

简介：Spilite-keratophyreisakeymemberoftheShuangxiwuGroupvolcanicseriesinZhejiangProvince.PresentedinthispaperarethereliableSm-Ndinternalisochronage(1012±18Ma,∈Nd(T)=4.4±0.1)andwhole-rockRb-Srisochronage(972±40Ma,Isr=0.70327±8)obtainedforthefirsttimebytheauthors.FromtheavailableNd,SrandOisotopedatainconjunctionwiththemajorandtraceelementsdataitissuggestedthattheXiqiuspilite-keratophyreistheproductofisland-arcvolcanismduringthelateMiddleProterozoic.

简介：Yangtze平台上的NeoproterozoicDoushantuo形成，华南，从碳酸盐站台与不同沉积相记录沉积继任倾斜，到深海盆，和主机，世界级的磷钙土之一扔。在这些阶层，精致地保存了石块被发现了：Weng“一个生物区系。这研究介绍被联系的碳同位素地球化学从Weng配对碳酸盐和有机物“一个碳酸盐平台的节(Yangtze站台的架，贵州省)从一条转变带的Songtaosection和Nanming节(Yangtze站台的斜坡，贵州省)并且从Yanwutan节(Yangtze站台的盆区域，湖南省)。Yangtze站台上的Environmentalvariations和简历事件在迟了的Neoproterozoic和他们的原因的关系期间被讨论。为碳酸盐和器官的碳的否定的碳同位素价值(meandelta~(13)C_(org)=-35.0每千)从最高Nantuo形成被delta~(13)的全面增加跟随C起来节。碳同位素价值每千为碳酸盐并且在-35.6之间每千每千and3.6在-9.9之间变化并且-21.5每千为器官的碳分别地。更重的delta~(13)C_(carb)价值在器官的碳埋葬建议增加，可能与增加生产率有关(例如Weng“一个生物区系)。从Doushantuo形成的沉积的delta~(13)Cvalues经由斜坡从站台减少了到盆，可能反映有次要的溶解的无机的碳的减少的环境由于更在下初级生产率。这被推出在welling过程，层化结构和热水的爆发上面古典主要是重要机制从Doushantuo形成解释沉积的碳同位素组成。

简介：Datingofmetallicoredepositshasbeenoneoftheproblemsconcernedwithbyoregeologistsformanyyears.TheestablishmentoftheRe-OsIsotopeLaboratoryattheInstituteofRockandMineralAnalysis,ChineseAcademyofGeologicalSciences,hasprovideduswithanewtechniquetocarryoutgeochronologicalstudiesofmolybdenumores.AsoneofthemostimportantRe-bearingminerals,molybdenitecontainsalmostnocommonosmium,but^187Oswasderivedcompletelyfromdecayof^187Re,with^187OscontentasthefunctionofRecontentinthemineral.AnID-ICP-MStechniquehasbeenusedinthisstudy,andRe-Osisotopicagesofseverallargemolybdenumdepositsofdiffer-enttypesfromtheEastQinlingmolybdenumbelthavebeendetermined.ItisindicatedthattheHuanglongpucarbonatitevein-typemolybdenum-(lead)deposithasaRe-OsagecorrespondingtoIndosinian,whiletherestporphyry-typemolybdenumdepositsandporphyry-skarn-typemolybdenum-(tungsten)depositshaveRe-OsagescorrespondingtoYenshanian.

简介：Theanisotropicpotentialdevelopedinourpreviousresearchandtheclose-couplingmethodareappliedtotheHBr-3He(4He,5He,6He,7He)system,andthepartialcrosssections(PCSs)attheincidentenergyof60meVarecalculated.Basedonthecalculations,theinfluencesoftheisotopeheliumatomonPCSsarediscussedindetail.TheresultsshowthattheexcitationPCSsconvergefasterthantheelasticPCSsforthecollisionenergyandthesystemsconsideredhere.AlsotheexcitationPCSsconvergemorerapidlyforthehigh-excitedstates.Thetaileffectispresentonlyinelasticscatteringandlow-excitedstatesbutnotinhigh-excitedstates.Withtheincreaseofreducedmassofthecollisionsystem,theconvergingspeedoftheelasticandexcitationPCSsslowsdown,andthetaileffectgoesup.

简介：在论文，在中国的降水同位素观察网络的发展被考察，并且在isoscape的最近的成就和降水马厩同位素的环境效果被总结；水文学过程研究也在最近的十年期间基于在中国的降水同位素被考察。在过去的十年，降水同位素的空间、季节的模式全国被调查了，特别在在GNIP(在降水的同位素的全球网络)和CHNIP(在降水的同位素的中国网络)的建立的参予以后，尽管长期的大小仍然被限制；除全国性的网络以外，一系列地区性的网络广泛地越过中国被建立了。从绘画到计算机的传统的手册--印射帮助，然后使用装备同位素的模型，到模拟降水isoscape的生产被改进了。控制降水同位素的主要因素被总结，并且在气候代理的同位素的潜在的意义被提及。关于雨点的影响的最近的研究同位素上的云下的第二等的蒸发被考察；基于降水同位素和另外的参数，在本地降水的再循环的潮湿(蒸发和蒸发)的贡献能用三部件或二部件的混合模型被估计。最后，在中国的降水同位素研究的一些前景被介绍。

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