资源描述：
《大学专业英语课件》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、Mineralogyandgeochemistryoftraceelements inbauxites:theDevonianSchugorskdeposit,RussiaL.E.MORDBERG1,2,3,C.J.STANLEY2,ANDK.GERMANN31.RussianResearchGeologicalInstitute(VSEGEI),Srednypr74,St.Petersburg,Russia2.TheNaturalHistoryMuseum,CromwellRoad,LondonSW75BD,UK3.TechnischeUnive
2、rsita¨tBerlin,Lagersta¨ttenforschung,Sekr.BH4,Ernst-Reuter-Platz1,10587Berlin,GermanyAbstract:Processesofmineralalterationinvolvingthemobilizationanddepositionofmorethan30chemicalelementsduringbauxiteformationandepigenesishavebeenstudiedonspecimensfromtheDevonianSchugorskbauxi
3、tedeposit,Timan,Russia.Chemicalanalysesofthemineralswereobtainedbyelectronmicroprobeandelementdistributioninthemineralswasstudiedbyelementmapping.Interpretationofthesedataalsoutilizedhigh-resolutionBSEandSEimages.SpecializedVocabulary:Mobilization[məubilai'zei-ʃən]n.动员;调动Forma
4、tion[fɔ:'meiʃən]n.构造,编队,形成Epigenesis[epi'dʒenisis]n.渐成说;[地]外力变质;后成specimen['spesimən]n.样本,标本electronmicroprobe电子微探针;电子显微探针;电子探针Themainrock-formingmineralsoftheVendianparentrockarecalcite,dolomite,feldspar,aegirine,riebeckite,mica,chloriteandquartz;accessorymineralsarepyrite,ga
5、lena,apatite,ilmenite,monazite,xenotime,zircon,columbite,pyrochlore,chromite,bastnaesiteandsomeothers.Typically,thegrainsizeoftheaccessorymineralsinbothparentrockandbauxiteisfrom1to40mm.However,evenwithintheserathersmallgrains,theprocessesofcrystalgrowthandalterationduringweat
6、heringcanbedeterminedfromthezonaldistributionoftheelements.Themostwidespreadprocessesobservedare:SpecializedVocabulary:parentrock母岩Calcite['kælsait]n.[矿]方解石Dolomite['dɔləmait]n.白云石Feldspar[‘feldspɑ:]n.长石Aegirine['eiɡə,ri:n]n.[矿]霓石riebeckite['ri:bekait]n.钠闪石mica['maikə]n.云母chlo
7、rite[‘klɔ:rait]n.绿泥石quartz[kwɔ:ts]n.石英accessoryminerals副矿物pyrite['pairait]n.[矿]黄铁矿galena[ɡə‘li:nə]n.[矿]方铅矿apatite['æpətait]n.磷灰石ilmenite[‘ilmənait]n.[矿]钛铁矿PleasefollowthenextpagefortheotherSpecializedVocabularyofthispage(1)DecompositionofTi-bearingmineralssuchasilmenite,aegiri
8、neandriebeckitewiththeformationof‘leucoxene’,whichisthemainco
