简介：Themulti-stagegeologicalevolutionandextensivecontinentaldeformationsduringthecourseofitshistorymaketheCentralAsianmetallogenicregion(CAMR)auniqueandcomplicatedlarge-scalemetaldomain.Newgeologicalobservationsandpreciseage-dataallowanimprovedreconstructionofthegeologicalevolutionoftheCAMR.ThispapersummarizesthePaleozoicorogenicevolutionandrelatedoreformationinthecorepartoftheCAMRbasedonthegeologicaldatapublishedbothduringtheSovietperiodandthelastdecades.Fourore-formationprovinces(Altay,BalkhashJunggar,Chu-Yili-Tianshan,andSouthwestTianshan)couldbeclassified.TheBalkhash-JunggarandChu-Yili-Tianshanprovincesarethemajortopicsofthispaper.TheBalkhash-Junggarprovinceconsistsof4hugeore-formingbelts(Zharma-Saur,Tarbahtay-Xiemistay,Aktogay-Baerluke,BalkhashwesternJunggar)with11largeore-collegeareas.TheChu-Yili-Tianshanprovinceconsistsof4hugeore-formingbelts(Alatau-Sairimu,Chu-Yili-Bolehuole,Issyk-Awulale,Kazharman-Nalaty)with22largeore-collegeareas.Formationoflargeore-collegeareacorrespondstoaspecificstageofcontinentalcrustgrowth.ComparisonofgeologyandoredepositsintheCAMRprovidesrichinformationforfutureexplorationandunderstandingofore-formingprocesses.ThePaleo-JunggarOceanclosedatEarlyDevonianintheBalkhash-westernJunggarore-formingbelt.Afterwards,widespreadvolcanic-sedimentaryrocksformedatextensionalstageduetodelaminationofthethicklowercrustformedduringpreviousaccretionaryprocesses.FelsicmagmaintrusioncausedformationofporphyryCu-Audepositat~310Maandrelatedhydrothermalgolddepositsabout10Malater.Forexample,intheHatu-Baobei-SartohayAu-Crore-collegeareaintheBalkhash-westernJunggarore-formingbelt,smallgranitictodioriteplutonsandvariousdykes(312–277Ma)andlargegranitebodies(~300Ma)intrudedintotheDevoniantoEarlyCarboniferousvolcano-sedimentarybasin.Thesemagmaticactivities

简介：Ceriumisoneofmultivalentrearearthelements,whichcantransferfromtrivalencetotretavalenceatoxidizingenvironment.ThisprocessmaycausevariabledegreesoffractionationofCefromothertrivalentrearearthelements,andthusmayprovidespecificinsightintothegeologicalprocessesassociatedwithmarkedredoxomorphism.MultiplegeochemicaltracingofSr-Nd-CeisotopesareperformedonthefelsicandmaficintrusivesoftheNeoproterozoic(~800Ma)HuanglingcomplexlocatedattheeasternThreeGorges,SouthChina.TheintrusiverocksexclusivelyshowvariousextentsofnegativeCeanomalies.OntheεCe-εNdplot,mostsamplesfromthemaficintrusionsscatterwithinthesecondquadrant,whereasthosefromthefelsicintrusionswithinthefourthQuadrant.Bothofthetwogroupsexhibitrelativelylargerangeof?Ce(t)variationbutlimited?Nd(t)range,whichcauseadeviationfromthe'crustalarray'andrevealadecoupledNd-Ceisotopecorrelation.Theintermediate-felsicsuitehavevariedCe/Ce*ratiosbutbroadlyproximateεCe(t)values,indicatingthattheirnegativeCeanomaliesweregeneratedduringthemagmatism;onthecontrary,apositivecorrelationbetweenεCe(t)andCe/Ce*isobservedfortheintermediate-maficsuite,anindicationofanoriginofpost-magmaticalterationormetamorphismfortheirCeanomalies.Calculationofmodelage,theoccurrenceageofnegativeCeanomalies(TCe)fortheintermediate-maficsamplesinfersthatthealterationeventstookplace>350Ma.DatashowedthatnegativeCeanomaliesofthefelsicintrusionsmayreflectanincreaseofoxygenfugacityduringmagmaascending,ratherthananinheritancefromtheirsourcerocks.ThisexplanationimpliesthattheNeoproterozoicmagmatismoccurredatthecontinentalnucleusoftheYangtzeblockweredevelopingatageodynamiccontextofrapidlyregionaluplifting.