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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.

3 1 : - - U-Pb 35 3 (CL) Fig.3 Cathodoluminescence(CL)imagesofzircongrainsfromtheJitoupluton 1600, : 15kV, A, 1μm, ZAF Isoplot/Ex ver3 [9] [7] Fe 2+ Fe U-Pb 3.1, 3.1.1, 150, ( 2-a,b),,, 0.5~2mm U-Pb 1, ( 4), (LA-ICP-MS),, NISTSRM612, (REE,U,Th,Pb) 3 RSD<3% ; :15~20s,40s,45~55s ; 5~10 ( ) Plesovice SL ; NISTSRM 612, 29Si GLITTER ver4.0, Ander- 4 son [8] ComPbCorr# 3.17,U-Pb Fig.4 Classificationdiagramofplagioclaseinthequartzdiorite

4 An,,,,, 2, w(na 2O), w(cao),(ca B+Na B ) 1.34(B ),Na B<0.67,,, 1mm, ( 5-a) 1 Table1 Compositionandcalculationresultofplagioclaseinthequartzdiorite 008-2( ) ( ) 056-2( ) SiO Al2O CaO Na2O w B /% K2O Si Al Ca n Na K An Ab Or :An. ;Ab. ;Or. ; 2 Schmidt [10] P = Table2 Compositionandcalculationresultofamphibolein thequartzdioriteandinclusionsofjitoupluton Al T, 204~563MPa, 3 : 19km , 11~15km ( ) SiO , 7~8km TiO Al2O ,, FeO MnO w B /% ( 5-b) MgO , CaO , - Na2O K2O An=34~49, 92; Si T Si=6.45~6.93, 7.8 Blun- Al Ⅳ dy [11] Al Ⅵ Ti n Fe Fe CaB NaB NaA KA /MPa /km : Al Ⅳ Al Ⅵ, A,B,T T= 0.677P Y lnK ( ) :K= Si-4, Si 8-Si XAb Si ;P MPa, ;X Ab Ab, X Ab>0.5,Y=0; X Ab<0.5,Y= (1-X Ab ) 2, ~ ( 3)

5 1 : - - U-Pb 37 5 ( [12])(a) w(tio 2 )-w(al 2O 3 )(b) (A,B ) Fig.5 Classificationmapforamphibole(a)andTiO 2-Al 2O 3 (b)diagramofamphibole ,U Th Th/U, 0.67~1.20( 4), Table3 Compositionandcalculationresultoftheplagio- claseassociatedwithamphiboleinthejitoupluton [13], U Th, Pb/ 238 U 146~137 Ma( 4), SiO Al2O , ( 6-a), Pb/ 238 U CaO w B /% (141.6±1.1)Ma(MSWD=0.79), Na2O K2O XQ- Si Al TW4 20 Ca n Na K An Ab Or t/ U-Pb , ( 6-b), 206 Pb/ 238 U XQ-TW2 16 (129.95±0.6)Ma(MSWD=1.8), ( 3), U Th ~ , ~ ( 3), U Th ~ , ~ ,Th/U, ~ ( 4), Pb/ 238 U 134~127.5 Ma( 4), 6 XQ-TW2(a) XQ-TW4(b)U-Pb Fig.6 ZirconU-PbconcordiadiagramfortheJitoupluton (XQ-TW2 (a)andxq-tw4 (b))inxinqiao

6 Th 238 U w B / LA-ICP-MS Table4 LA-ICP-MSzirconU-PbdatingresultsoftheJitouplutoninXinqiao Th/U t/ma 207 Pb/ 206 Pb 1σ 207 Pb/ 235 U 1σ 206 Pb/ 238 U 1σ 207 Pb/ 235 U 1σ 206 Pb/ 238 U 1σ (143±1)Ma, 206 Pb/ 238 U 139 Ma [15], 4.1 (141.0±1.1)Ma [16], ( Ma ±1.1)Ma 206 Pb/ 238 U, 4.2,, [17-23] [14] ( )Ma, (129.95±0.6)Ma 206 Pb/ 238 U,, 2 (141.3±9.2)Ma (133.3±3.2)Ma [15],,,, 206 Pb/ 238 U ( 2),

7 1 : - - U-Pb 39 U-Pb (141.6±1.1)Ma, ( 5-b), LA-ICP-MS U-Pb (129.95±0.6)Ma, [6,14,23-24] [21], 2, 141 Ma 204~ (2) 800, MPa, 6.7~18.6km, ~15km,,, ~ ( 3), 7~8km, : 800, (3)2, 13~15km, [18-19],, 7~8km,, 4.3 :, [1],,,. [M]. :,1998., [2],. :, [J].,1983,2(1): [3],,,., [J].,2001,30(2): [4],,. ( ) [25] [J].,2010(8): [5],,,. He Ar Re-Os, [J].,2004,18(4): (126±1.1)Ma,, 2 (129.9±0.6)Ma [26], Re-Os (138±26)Ma, (141.6±1.1)Ma [27], Rb-Sr 113 Ma,,, 2 79., [28] 140~110 Ma, δ 34 S, gycenter,2003.,, (2/3): , 207 Pb/ 204 Pb ~15.762, 207 Pb/ 204 Pb,, Mineralogist,1978,16(4): , [13],, [J]., [14],, 5 (1) LA-ICP-MS [6],,,. [J].,2013,23(6):1666- [7]. Fe3 Fe2[J]., 1983,3(1): [8] AndersonT.CorrectionofcommonPbin U-Pbanalysesthat donotreport 204 Pb[J].ChemicalGeology,2002,192(1/2):59- [9] LudwigK R.Isoplot3.00:AgeochronologicaltoolkitforMi- crosoftexcel[m].berkeley,california:berkeleygeochronolo- [10]SchmidtM W.Amphibolecompositionintonaliteasafunction ofpressure,anexperimentalcalibrationofthealinhornblende barometer[j].contributionto MineralogyPetrology,1992,110 [11]BlundyJD,HolandTJB.Calcicamphiboleequilibriaanda newamphibole-plagioclasegeothermometer[j].contribution to MineralogyandPetrology,1990,104(2): [12]LeakeB E.Nomenclatureofamphiboles[J].TheCanadian. U-Pb,2004,49(16): ,. : SHRIMP [J]., 2004,25(4): [15],,,. SHRIMP U-Pb [J]., 2004,23(4):

8 [16]. [D]. [23],,,. :,2010. [17],,, [J]. [24]. - -,2011,85(5): [D]. :, ,21(1): Cu-Fe [J].,2001,11(2): [20],,, : - [27],,,. [J].,2007,23(6): [21],,.,2004,50(5): [J].,1995,16(2): [J].,2012,28(10): 192. Os [J].,2015,31(4): Rb-Sr : [J]. [28]. - [22],,,. [J].,2003,25(3): [J].,2012,86(3): PetrographyandU-PbZirconGeochronologyofthe JitouPlutonintheXinqiaoCu-S-FeDeposit,TonglingArea, AnhuiProvince,andItsGeologicalSignificance SongYang 1,DuYangsong 1,ZhangZhiyu 2,MaHong 1,ZhuXiaoqiang 1 (1.SchooloftheEarthSciencesandResources,ChinaUniversityof Geosciences(Beijing),Beijing100083,China; 2.InstituteofGeology,ChineseAcademyofGeologicalSciences,Beijing100037,China) [18],,. [25],,,. Cu-Au-Fe-S : [J]., Re-Os [J].,2009,44(1):183- [19],. [26],,. Re- Abstract:TonglingoredistrictiscloselyrelatedtotheMesozoicintrusiveigneousrockswhichisequivalent tosomedepositsintheyangtzerivermetalogenicbelt.thepaper,takingthejitouplutonasthestudy object,studiesla-icp-mszirconu-pbdatingtosupplementxinqiaopluton'sgeologyandmineralogycon- tent.thehighth/uratiosandtypicalmagmaticoscilatoryzoningofzirconsindicatetheirmagmaticori- gin.theweightedaverageageofthequartzdioritefrom16testingspotsinthemajorpartofxinqiaoplu- tonis(141.6±1.1)ma,whiletheweightedaverageageofthelateintrusivedioritedikesfrom20spotsis (129.95±0.6)Ma,bothofwhichwereformedintheEarlyCretaceous.Thereareatleasttwotimesof magmaticactivity,withthemainmagmatismtimeat141ma.themagmaisderivedfromthedeepmantle emplacingalongthetectoniccracktothe middlecrust (about13-15km)andformedthedeep magma chamberaccompaniedbyfractionationcrystalizationandassimilation.then,undertheinfluenceofgeo- logicalstructure,themagmainthedeep magmachamberemplacedagainalongtheweaktectoniccrackto theuppercrust(7kmto8km)andeventualyformedthejitoupluton,withthecrystalizationtempera- tureabout800.xinqiaodepositwasformedthroughthehigh-temperaturehydrothermalmetasomatic, andsuperimposedhydrothermalprocessmanytimeslater. Keywords:Jitoupluton;mineralogy;zircondating;XinqiaoCu-S-Fedeposit;TonglingofAnhuiProvince

GeologicalScienceandTechnologyInformation Vol.37 No.3 May 2018 doi: /j.cnki.dzkq ,,,. [J].,2018,37(3):13-20.,,, (, )

37 3 2018 5 GeologicalScienceandTechnologyInformation Vol.37 No.3 May 2018 doi:10.19509/j.cnki.dzkq.2018.0302,,,. [J].,2018,37(3):13-20.,,, (, 510080) : SN NWW U-Pb (148.6±4.1)Ma(MSWD=1.3) (85.7±2.0)Ma(MSWD=1.4)