简介：Theresultsof118REEanalysesofLi-FgranitesfromSouthChinaandothercountriesindicatethattherearethreevariationtypesofREEpatterncurveswithdifferentevolutiontrendsfromearlytolatestagesofLi-FgranitecomplexoffromlowertoupperpetrofaciesoftheLi-Fgranitebody;(1)thedecreasing,(2)theincreasing,and(3)thesaltatoryvariationtypes.Thefirstvariationtypeiscalledthepositiveevolutiontype,attributedtocrystallizationdifferentiation.Thesecondiscalledthereversionevolutiontype.whichrepresentsliquidsegreationdominatedbyvapor-liquiddistillation.Thethirdiscalledthesaltatoryvariationtype,whichisformedfromliquidsegregationdominatedbyimmiscibilty,Therefore,theindicaticesofliquidsegregationdominatedbyimmiscibilityarethesaltatoryvariationtypeofREEpatternevolutionandtheseparationofthemainevolutiontrendlineseitherfromthesub-evolutiontrendlinesorfromthecompositionpointsofLi-FgranitesinthediagramsofREE-(La-Yb)NandLa/Sm-La,Theindicatricesofliquidsegregationdominatedbyvapor-liquidfractionaldistillationarethereverstionevolutiontypeofREEpatterncurvesandthemainevolutiontrendlinesofLi-Fgranitesdirectingtotheupperright-handontheREE-La/Yb)NandLa/Sm-Ladiagrams.

简介：Li-Fgranitesallovertheworldcanberepresentedbythreeendmembers,i.e.,theNa-richongonite(O),theK-richxianghualingite(X)andtheSi-richtopazite(T),Charactersandcriteriaarepresentedfortheseend-mnemberrocks,VerticalzoninginLi-Fgranites,asreflectedbyincreasingnormativeQandC(corundum)anddecreasingALK(K2O+Na2O)withincreasingcontentoffluorine,canbeexplainedusingthethree-end-memberschemeintermsofpetrochemistryandnorms.Consideringthedifferenceinmeltstructure,visocosityanddensitybetweentheendmembers,incouplewiththeregulartiesthatgoverntheNa-KandSiALKsegregationknownfromfieldevidenceandexperiments,itissuggestedthatthethreeendmembersmayhaveresultedfromliquidsegregation(immiscibility)ratherthanfromcrystalfractionationascommonlybelieved.

简介：　　0引言　　世界上第一个Ar-Ar法实验室于1965年在美国加州伯克利年代学实验室建成[1].我国最早的Ar-Ar法实验室于1982年分别在北京中国科学院地质研究所和贵阳中国科学院地球化学研究所建成.到目前为止,国际上用于K-Ar和Ar-Ar法定年的标准物质约30个左右,绝大部分年龄为第三纪至寒武纪.大于6亿a的K-Ar法年龄标准物质只有英国标准Hb3gr角闪石(年龄1072Ma)和中国标准BSP-1角闪石(年龄2060Ma),这两个老年龄标准也是国际标准物质.　　……