a. ;b. ;A~F 1 ( [4] ) Fig.1 IlustrationoftheprincipalmotivationsbehinddevelopmentofFT-U/Pbtriple-datingordouble-datingofdetritalapatite, U-Pb

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1 GeologicalScienceandTechnologyInformation Vol.36 No.1 Jan doi: /j.cnki.dzkq ,,,. [J].,2017,36(1): ,2, 3, 4, 1,DavidChew 2 (1., ;2.DepartmentofGeology, TrinityColege,Dublin2,Ireland;3., ; 4., ) : -, - LA-ICPMS U-Pb ( FT-U/Pb ), - FT-U/Pb, Pb Pb,, -,, FT-U/Pb, - - : ; ;FT-U/Pb ; ; ; :P :A : (2017) ,, ( ) -, :, -, [1-3], 20a U Th Pb,,, U-Pb (ZFT) (U-Th)/ [4,9] ( multiplechronologyor multi- He(ZHe) dating ) U Th Pb, [4-8] -,,, - - [10-11], ( 1), :1, (U-Pb ) [ (FT) (U-Th)/He [11-12] [5-8] ] ;2, : : : ( ; ;2014JQ0057;2017JQ0025) : (1980 ),,, dengbin13@mail.cdut.edu.cn

2 a. ;b. ;A~F 1 ( [4] ) Fig.1 IlustrationoftheprincipalmotivationsbehinddevelopmentofFT-U/Pbtriple-datingordouble-datingofdetritalapatite, U-Pb FT He [5-6], 1-a 2 (A F ) U-Pb FT 4 (B He [7-8] ~E ) U-Pb AFT/AHe FT U-Pb [7,16-17], ; FT-U/Pb U-, Pb FT A,, ( F ) 1-b B C (, ),A B D E ( )He ( U-Pb ),, 235 U α,, ( A F ), zeta, ( ) [18-20] (LA-ICPMS), (, F), U-Th-Pb, FT U-Pb [7,16,21] 1 Hasebe [21] LA-ICPMS U, 1.1 U-Pb (fissiontrack,ft) :1 10μm 266nm ND YAG triple-dating, U-Pb ( ) (apatitefissiontrack,aft) (U-Th)/He 50μm 50μm, ICPMS U (AHe) ;2 doube- Hasebe [21], dating, U-Pb 238 U (λf) ( ) U-Pb FT He LA-ICPMS AFT ( 550~ ~100 80~60 [13-15], [21-22]) Hasebe [23] -

3 1 : 79 LA-ICPMS U Ba 2+ Fe 2+ ) 43 Ca,, 3U-Th-Pb Chew [7] LA-ICPMS 43 Ca, FT-U/Pb ( : 43 Ca ( :Mn Durango,Emerald Lake,Kovdor,Minevile,Mud- Fe Mg Fe Sr Ba Y REE ) tank,oterlake Slyudyanka ), 43 Ca 30μm 193nm ( ) ICPMS ( ) 10μm 40μm 40μm, U-Th- 1.2 U-Th-Pb Pb, ;, 238 U (LA-ICPMS) U- 43 [27-28] Ca, Pb, ( ) Ple ovice 91500,NIST SRM 610 [29] NISTSRM612 STDP5 Kovdor U-Th-Pb U-Pb Th-Pb, ( Back- ICPMS LA-ICPMS calculatedintercept ),,, U- Tl-U-Bi-Np / Th-Pb, [7,16] [30-31] ICPMS, Thomson [24] 30μm U-Pb,,Paton [32] ( U ) (65,,U-Th-Pb μm ), ( Mad- session-specificmodel agascar McClureMountain ) [33] ( ) ; FT [30,34], FT,, ( U-Pb ) ( AFT (matrix-matchesstandard) [28,31] ) ( ),LA-, ICPMS ( /, :Mg Cl Mn Fe Y Ce / ),,, U-Th-Pb [25-26], LA-ICPMS, U-Th-Pb :1 Pb LA- ( ) U ICPMS U-Pb NIST [5,7,35] ( ) FT U-,LA-ICPMS Pb, U U-Pb (, 2), 10% ~20% [24] 2LA-ICPMS,FT-U/Pb ( :Mn 2+ Sr 2+ [7,24] Kovdor[(387±8.2)Ma;w(U)=56

4 ,w(Th)= ,w(Pb)= ] EmeraldLake[(92.5±3.3Ma;w(U)= , w(th)= ,w(Pb)= ) Sly- udyanka (448±7.3 Ma;w(U)= ,, U Th Pb, [7] LA-ICPMS FT-U/Pb, [36] U Th Thomson [24] McClure mountain [(523.5± w(th)= ,w(Pb)= ] 1.4)Ma;w(U)= ,w(Th)= ,, Durango (31.44 w(pb)= ] LA-ICPMS Ma),Kovdor FT-U/Pb McClure (ID-TIMSapatiteU-Pb Ma)LA-ICPMS (A)SL2 (B)BearLake, SL2 BearLake 10%~20% 2 [24] Fig.2 DiferentfractionationstandardsoftheSL2zircon(A)andtheBearLakesphene(B)inLA-ICPMS McCluremountainapatite U-Pbdating Pb, :, U Th, Pb Pb [37-38], Pb/U FT U-Pb,, FT-U/Pb (1) (, ), 206 Pb/ 238 U [7,38] 207 Pb/ 235 Pb 207 Pb/ 206 Pb U/Pb Pb/Pb, [39], MSWD, FT-U/Pb, U-Pb( ), U- FT- Pb, :Chew [7] 20 U/Pb, Tera-Wasserburg μm 10μm 207 Pb/ 206 Pb (y-inter- [7,40], cept) Thomson [24] 30μm (2) Pb, U U-Pb( ), Pb/ Pb :Pb Pb 208 Pb ( :65μm) U-Pb [41-42] 204 Pb 204 Pb 1.3, 206 Pb/ 204 Pb, ID-TIMS MC-ICPMS Pb U-Th-Pb [24,42-43], :Carrapa [5] BearLake

5 1 : 81 SirLanka NISTSRM610, 204 Pb 207 Pb 208 Pb 238 U/ 206 Pb- 207 Pb/ 206 Pb 238 U/ 206 Pb- 208 Pb/ 232 Th U-Pb, 238 U/ 206 Pb 207 Pb/ 206 Pb Pb ; 238 U/ 206 Pb 232 Th/ 238 U 208 Pb/ 206 Pb, [41-42] Th/U( <0.5), : Th 208 Pb Pb [44] 207 Pb/ 206 Pb, U-Pb Pb Pb/ 238 U/ 206 Pb(, ) ; U-Pb,, FT-U/ 238 U/ 206 Pb( ) Pb,, Pb U-Pb T-W ( [17]) 204 Pb 207 Pb 208 Pb Fig.3 ApatiteFT-U/Pbdatingusingthe 207 Pbcorrectionmethodol- Pb, 207 Pb 208 [7,16] Pb ogyintera-wasserburgu-pblowerconcordiadiagramandits Pb Pb efectsofu-pbelementalfractionation, Pb Pb ( U-Pb FT [16,24] Pb He Chew [17], Pb, session-wide U-Pb ) FT-U/Pb,, U-Pb FT He, ( :Madagascar, Durango OLT1 R10 FT-U/Pb U-Pb ), LA-ICPMS FT-U/ FT He Pb Pb 204 Pb 207 Pb 208 [4,46-47] Pb, U-Pb Reiners [4] Zatin [46], ( ) Pb U-Pb Th-Pb ( 3) Mississippi VictoriaLand, 2 FT-U/Pb FT- U/Pb ( 4-A,B) 2.1, FT-U/Pb, - Reiners [4], Mississippi - [4,45], FT U-Pb (U-Th)/He, U-Pb ( FT He ), U-Pb FT ( )He ( 1,4), 0 Ma FT-U/Pb, 3 ( 4-C,D):150~40 Ma

82 2017 U-Pb ( )He ( :Ma) 4 ( [4] ) Fig.

6 U-Pb ( )He ( :Ma) 4 ( [4] ) Fig.4 ApatiteFT-U/Pbagedistribution ;2 Ross 50~40 Ma U-Pb, ;3 50~40 Ma ( AFT 40 Ma AFT FT-U/Pb, 40 Ma 40 Ma2 ), VictoriaLand ( CentralTam) 4-B 4-A FT-U/Pb, U-Pb 120 Ma, FT Ross, He U-Pb ( 0 Ma ) Ross Victoria U-Pb, U-Pb 4-D 600~580,580~560,560~540,540~520 Ma 4-C FT-U/Pb, Oliveti [47] Victoria U-Pb FT/He ( FT-U/Pb, 40,48 Ma) U-Pb 120 Ma AFT 40 Ma, FT He U-Pb 40 Ma ( 0 Ma ) AFT Rose,, U-Pb 2200~ U-Pb 620Ma 530Ma 40 Ma, FT He 55~40 Ma,, U-Pb 4 ( :, Victoria ) , -,,

7 1 : 83 U-Pb FT He, FT ( ) ( )He, (U-Th)/He ( 50~80 [15] ), [48-50], He, :1 ;, U-Pb 2 ( FT He );3( ±1σ ) [4,51] ;4( ±2σ ) 3 Dick- U-Pb FT He inson [11] Colorado, ( U-Pb 5-b),, (U-, Th)/He He,, U-Pb AHe (, 60% U-Pb ), (U- 5 Ma, Th)/He 80, U-Pb, AHe ICP-MS FT- ( 5), U/Pb AFT, :1, AHe ( ) ;2 AFT, U-Pb U-Pb,,;3 U-Pb FT ( )He, [51],AFT AHe, AFT-AHe 5 FT-U/Pb ( Fig.5 EfectofprogressiveburialheatingondetritalapatiteFT-U/Pbages [51] ) ,, FT-U/Pb, -, :1 ( 6) [4,47,51] ;2 ; (lag-time),

84 2017,, ( 5) Fosdick [51] U-Pb He -, U-Pb (54~45 Ma), Magalanes 3 FT-U/Pb, - ;,,, 6 FT-U/Pb 204 Pb 207 Pb 208 Pb Pb ( [51] ) Fig.

8 ,, ( 5) Fosdick [51] U-Pb He -, U-Pb (54~45 Ma), Magalanes 3 FT-U/Pb, - ;,,, 6 FT-U/Pb 204 Pb 207 Pb 208 Pb Pb ( [51] ) Fig.6 Schematicilustrationofsedimentsourceterranesand ( ) Pb basinfilshowingthethermalevolutionfrom sourceto, deposition ( ) ( [1,52], - ),, [53],,, FT-U/Pb, -, : AHe, AFT,, FT-U/Pb, - Thomson [8] FT-U/Pb : 300~250Ma Ma 2 [1] BernetM,Zatin M,GarverJI,etal.Steady-stateexhumation, ofeuropeanalps[j].geology,2001,29(1): [2] FedoC M,SircombeK N,RainbirdR H.Detritalzirconanaly- sisofthesedimentaryrecord,inzircon[j].reviewsin Miner-, 2013,125:14-32., -,, FT He alogyandgeochemistry,2003,53: [3] CawoodPA,HawkesworthCJ,DhuimeB.Thecontinentalre- cordandthegenerationofcontinentalcrust[j].gsa Buletin, [4] ReinersP W,CampbelIH,NicolescuS,etal.(U-Th)/(He- Pb)doubledatingofdetritalzircons[J].AmericanJournalof Sciences,2005,305: [5] CarrapaB,DeCelesP G,ReinersP W,etal.Apatitetriple

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An,,,,, 2, w(na 2O), w(cao),(ca B+Na B ) 1.34(B ),Na B<0.67,,, 1mm, ( 5-a) 1 Table1 Compositionandcalculationresultofplagioclaseinthequa

An,,,,, 2, w(na 2O), w(cao),(ca B+Na B ) 1.34(B ),Na B<0.67,,, 1mm, ( 5-a) 1 Table1 Compositionandcalculationresultofplagioclaseinthequa 1 : - - U-Pb 35 3 (CL) Fig.3 Cathodoluminescence(CL)imagesofzircongrainsfromtheJitoupluton 1600, : 15kV, 7 10-8 A, 1μm, ZAF Isoplot/Ex ver3 [9] [7] Fe 2+ Fe 3+ 2.2.2 U-Pb 3.1, 3.1.1, 150, ( 2-a,b),,, 0.5~2mm