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) Ba Rb K, Ta Nb Zr Hf P Ce (δce =0.89~0.93) Eu (δeu=1.00~1.05),th/yb Th 2 - Ti-Fe (148.6 Ma) (85.7 Ma) : ; ; ; :P588.12 :A :1000-7849(2018)03-0013-08,, 2 U-Pb ( ),, (N24 00 00 ~24 20 00 ;E114 00 00 ~, 114 30 00 ) ( 1),, 3 90 Ma : (Pt 2-Pz 1 ) -, [1] 105 Ma [2] [3],, (Pz 2 ), 140,105,90 Ma3 -, ;, NE (T 3 ) - Nb-Ta (J- [4] I, K) [5] 1 5, 1, :2017-10-10 : : 1 5 (12120113063100) : (1966 ),, E-mail:302533911@qq.com
14 2018 (γ 2-1 5 ); NE NW 2,NE (γ 5 2-3 ) (γ 5 3-1 ) -, (γ 3-2 5 ),,, - 1 ( [5] ) Fig.1 GeologysketchofXinfeng,NortheastGuangdong,,,,, Dy010 Dy011, 0.02~0.25 mm, (60%) N24 05 36,E114 11 12 N24 09 (30%) 37,E114 13 01,, Dy010 SN,, 2~2.5m Dy011 NWW, (γ 2-3 5 )( 2), 8~10m, ( φb =6%) (γ 2-3 5 )( 2) 2 0.8~1.5mm, (3%) (3%),, : (5%),, 0.5~1 mm,,, ;, 0.2~0.4 mm, 0.1~0.2 mm (60%) (40%) -,,,, 3 2 Fig.2 OutcropsandsamplingpositionsofmaficdikesinXinfeng (CL) U-Pb
3 : 15 (LA- Th-Pb Wiedenbeck [11] ICP-MS) ICPMSDataCal [6-8], 206 Pb/ 238 U Plesov- Isoplot/Ex ver3 [9] Pb ComPb- ice [12] :(337.13±0.37)Ma (2σ) Corr#3.18 [10] 91500 U- LA-ICP-MS U-Pb 1 Th U w B /10-6 1 LA-ICP-MS U-Pb Table1 LA-ICP-MSzirconU-Pbanalysesofmaficdikes t/ma / Th/U 207 Pb/ 235 U 1σ 206 Pb/ 238 U 1σ 208 Pb/ 232 Th 1σ 207 Pb/ 235 U 1σ 206 Pb/ 238 U 1σ 208 Pb/ 232 Th1σ % Dy010 01 323 592 0.55 0.1570 0.0110 0.0231 0.0007 0.0067 0.0003 148.04 9.61 147.24 4.32 135.27 6.59 99 02 1058 2958 0.36 0.1728 0.0079 0.0246 0.0007 0.0076 0.0003 161.88 6.82 156.97 4.41 153.42 6.50 96 03 89.2 189 0.47 0.1487 0.0110 0.0230 0.0007 0.0048 0.0003 140.80 9.73 146.60 4.50 96.75 5.99 95 04 413 928 0.44 0.1593 0.0084 0.0226 0.0006 0.0064 0.0003 150.10 7.32 144.30 4.05 128.07 5.88 96 05 330 972 0.34 0.1550 0.0086 0.0223 0.0006 0.0061 0.0003 146.35 7.57 142.09 4.07 123.53 5.96 97 06 422 503 0.84 0.1822 0.0111 0.0235 0.0007 0.0072 0.0004 169.94 9.52 149.74 4.42 144.14 7.34 87 07 816 1504 0.54 0.1762 0.0090 0.0241 0.0007 0.0071 0.0003 164.79 7.78 153.55 4.31 143.96 6.55 92 08 7.37 83.6 0.09 0.7215 0.0429 0.0809 0.0024 0.0356 0.0026 551.5325.30 501.2614.60 706.6051.69 90 09 317215004 0.21 0.0973 0.0044 0.0138 0.0004 0.0046 0.0002 94.24 4.11 88.49 2.61 93.53 4.15 93 10 188 429 0.44 0.1739 0.0108 0.0235 0.0007 0.0072 0.0003 162.79 9.32 149.74 4.34 145.46 6.74 91 Dy011 01 131 365 0.36 0.0804 0.0058 0.0138 0.0004 0.0042 0.0002 78.47 5.42 88.14 2.66 85.28 4.75 88 02 275 506 0.54 0.0890 0.0059 0.0136 0.0004 0.0038 0.0002 86.57 5.52 87.02 2.57 76.10 3.77 99 03 134 222 0.60 0.1044 0.0090 0.0147 0.0005 0.0043 0.0002 100.87 8.27 94.10 3.35 86.28 5.03 93 04 276 565 0.49 0.0960 0.0060 0.0138 0.0004 0.0042 0.0002 93.08 5.54 88.56 2.61 84.82 4.18 95 05 294 470 0.63 0.0921 0.0064 0.0131 0.0004 0.0038 0.0002 89.49 5.95 83.89 2.65 77.35 3.91 93 06 993 1923 0.52 0.0852 0.0042 0.0130 0.0004 0.0039 0.0002 83.03 3.94 83.54 2.44 79.03 3.40 99 07 196 194 1.01 0.1080 0.0087 0.0133 0.0004 0.0038 0.0002 104.13 7.95 85.46 2.79 76.81 3.59 80 08 98.2 250 0.39 0.0923 0.0071 0.0130 0.0004 0.0039 0.0002 89.63 6.57 83.11 2.65 78.72 4.47 92 09 275 619 0.44 0.0905 0.0059 0.0128 0.0004 0.0038 0.0002 87.98 5.51 81.80 2.48 77.63 3.72 92 10 96.9 51.3 1.89 0.1778 0.0174 0.0175 0.0007 0.0045 0.0002 166.13 15.00 111.70 4.29 90.86 4.71 60 11 479 1002 0.48 0.1601 0.0084 0.0212 0.0006 0.0061 0.0003 150.81 7.34 135.26 3.91 122.78 5.15 89 12 94.6 89.2 1.06 0.2922 0.0212 0.0345 0.0011 0.0106 0.0005 260.29 16.66 218.87 6.93 212.12 10.06 82 13 198 295 0.67 0.0925 0.0076 0.0133 0.0004 0.0038 0.0002 89.80 7.09 84.90 2.72 77.50 3.68 94 14 413 760 0.54 0.0878 0.0050 0.0131 0.0004 0.0037 0.0002 85.49 4.63 83.65 2.48 73.70 3.26 97 15 586 1073 0.55 0.1013 0.0056 0.0139 0.0004 0.0041 0.0002 98.02 5.21 88.74 2.67 82.48 3.74 90 3 2 Table2 Majorelementsdataandrelativeparametersof maficdikesinxinfeng Axios max X, H 2O - Dy010-1 Dy010-2 Dy010-3 Dy011-1 Dy011-2 Dy011-3, ( ) XSerise2 ( ) 2 3 4 U-Pb Dy010 -, 1 1~2 1, 100~ 300μm; Th/U 0.34~0.84, CL, 10 U- Pb 08 09, CL, 08 (501.26±14.6)Ma, 09 (88.5±2.61)Ma SiO2 50.59 50.62 50.75 49.91 48.97 49.19 TiO2 1.39 1.40 1.43 1.62 1.60 1.56 Al2O3 15.15 15.14 15.35 14.98 14.75 14.68 Fe2O3 2.31 2.28 2.66 3.40 3.31 3.91 FeO 8.48 7.98 7.70 8.08 8.25 7.72 MnO 0.16 0.15 0.14 0.15 0.15 0.15 MgO w B /% 6.23 6.43 6.27 7.37 7.62 7.06 CaO 8.19 8.65 8.41 7.73 8.43 8.09 Na2O 2.64 2.60 2.65 2.31 2.31 2.21 K2O 0.59 0.58 0.58 0.39 0.35 0.36 P2O5 0.15 0.15 0.15 0.18 0.18 0.17 3.93 3.91 3.78 3.74 3.94 4.68 99.82 99.89 99.88 99.86 99.86 99.77 TFeO 10.56 10.03 10.09 11.14 11.23 11.24 Na2O+ K2O 3.23 3.19 3.23 2.70 2.66 2.57 ACNK 0.59 0.56 0.58 0.63 0.57 0.60 K2O/Na2O 0.22 0.22 0.22 0.17 0.15 0.16 Mg # 0.51 0.53 0.53 0.54 0.55 0.53 :TFeO=FeO+0.8998 Fe2O3; Mg # = (MgO/ 40.3044)/(MgO/40.3044+TFeO/71.844)
16 2018 (MSWD=1.3) 3 ( 3), Table3 Traceandrareearthelementsdataandrelativepa- rametersofmaficdikesinxinfeng Dy011 - Dy010-1 Dy010-2 Dy010-3 Dy011-1 Dy011-2 Dy011-3, 1 1~2 1, 100~ Sr 262.20 210.48 247.41 231.73 226.63 255.40 300μm; Th/U 0.36~1.01,CL Rb 20.46 15.54 17.70 22.48 15.69 17.66, Ba 151.83 128.82 150.51 158.79 127.13 119.25 Th 2.76 2.08 2.07 1.73 1.30 1.46 15 U-Pb Ta 0.54 0.44 0.56 0.76 0.70 0.73, 15 10 11 12 Nb 11.33 6.84 8.01 10.79 10.01 14.94 90%,, 12 Ce 20.06 19.96 22.30 20.78 19.52 18.29, Zr 88.93 84.85 102.87 113.94 111.92 97.33 Hf 2.23 2.43 2.71 3.04 2.99 2.54 94.1~81.8 Ma, Sm 3.20 3.03 3.32 5.07 3.98 3.94 (85.7±2.0)Ma(MSWD=1.4), Y 17.81 15.44 20.10 38.74 27.36 29.02 Yb 1.74 1.61 1.76 2.98 2.35 2.38, ( 3) La 9.75 9.74 10.93 14.10 10.63 9.36 Cew B /10-6 20.06 19.96 22.30 20.78 19.52 18.29 Pr 2.83 2.54 2.91 3.82 3.01 2.91 5 Nd 12.63 11.60 13.04 17.68 13.95 13.62 Sm 3.20 3.03 3.32 5.07 3.98 3.94 5.1 Eu 1.12 1.01 1.13 1.48 1.33 1.36 Dy010 w(sio 2 ) 50.59%~50.75%, Gd 3.30 3.04 3.52 5.45 4.33 4.20 Tb 0.66 0.57 0.65 1.08 0.83 0.94 w(na 2O) 2.60%~2.65%,w(K 2O) 0.58%~ Dy 3.78 3.34 3.79 6.44 5.02 5.51 0.59%, w(k 2O+Na 2O) 3.19% ~3.23%, Ho 0.73 0.63 0.74 1.26 0.98 1.08 K 2O/Na 2O 0.22,w(Al 2O 3 ) 15.14% ~ Er 1.95 1.60 1.94 3.27 2.54 2.86 Tm 0.30 0.27 0.31 0.51 0.39 0.46 15.35%,w(TiO 2 ) 1.39%~1.43%,w(TFeO) Yb 1.74 1.61 1.76 2.98 2.35 2.38 10.03% ~10.56%,w(MgO) 6.23% ~6.43%, Lu 0.33 0.22 0.25 0.43 0.34 0.48 w(cao) 8.19%~8.65% ΣREE 62.37 59.15 66.59 84.34 69.21 67.40 Dy011 w(sio LREE 49.59 47.87 53.64 62.93 52.43 49.49 2 ) 48.97%~49.91%, HREE 12.78 11.28 12.95 21.42 16.78 17.91 w(na 2O) 2.21%~2.31%,w(K 2O) 0.25%~ Nb/Ta 20.90 15.47 14.35 14.18 14.25 20.57 0.39%, w(k 2O+Na 2O) 2.57% ~2.70%, Zr/Hf 39.92 34.94 38.01 37.54 37.38 38.39 K 2O/Na 2O 0.15~0.17,w (Al 2O 3 ) LREE/HREE 3.88 4.24 4.14 2.94 3.12 2.76 (La/Yb) N 3.78 4.09 4.20 3.19 3.06 2.66 δeu 1.05 1.00 1.01 0.85 0.97 1.02 δce 0.89 0.93 0.91 0.66 0.80 0.82 14.68%~14.98%,w (TiO 2 ) 1.56% ~1.62% (> 1%),w (TFeO) 11.14% ~ 11.24%, w(mgo) 7.06%~7.62%,w(CaO) 7.73% ~ 8.43% 8 2,, 156.97 TAS ~142.09 Ma, (148.6±4.1)Ma 3 LA-ICP-MS U-Pb Fig.3 LA-ICP-MSzirconU-PbageconcordiadiagramsofmaficdikesinXinfeng
3 : 17 ( 4-a), ; K 2O (4.55~6.67)>1,ACNK (0.56~ w(k 2O)-w(SiO 2 ) ( 4-b),Dy010 0.63) 1,,Dy011 ( ), Na 2O/ Fig.4 4 TAS (a) w(k 2O)-w(SiO 2 ) (b)(a [13]) MajorelementsdiscriminationdiagramsshowingTAS (a)andk 2O-SiO 2 (b)ofmaficdikesinxinfeng 5.2 Yb) N 3.78~4.20, Ce (δce= 2 0.89~0.93) Eu (δeu=1.00~, 1.05) Dy011 w(σree) 67.40 10-6 ~ 84.34 10-6,w(LREE) 49.49 10-6 ~62.93, Dy010 10-6,w(HREE) 16.78 10-6 ~21.42 10-6, w(σree) 59.15 10-6 ~ 66.59 10-6, (LREE/HREE) 2.76~3.12, w(lree) 47.87 10-6 ~ 53.64 10-6, (La/Yb) N 2.66~3.19, Ce w(hree) 11.28 10-6 ~12.95 10-6, (δce=0.66~0.82) Eu (δeu = (LREE/HREE) 3.88~4.24,(La/ 0.85~1.02) 5 (a) (b) Fig.5 Diagramsofchondrite-normalizedrareearthelements(a)and MORBnormalizedtraceelements(b)ofmaficdikesinXinfeng N-MORB ( (350 10-6 ), (17.8 5-b) (Ba Rb 10-6 w(sr) K),, Ta Nb Zr Hf P, [14], 6 P Dy010 Dy011 w(sr) 210.48 10-6 ~ 6.1 262.20 10-6 ( 240.03 10-6 ) 226.63 10-6 ~255.40 10-6 ( 237.92 10-6 [15-17] ),
18 2018 [17-18] Ti Fe, Dy010 Nb/Ta 14.35~20.90 w (Fe)[w (TFeO)=10.03% ~ 11.24%] w(ti)[w(tio 2 )=1.39% ~1.62%], [20] 6 Zr/Nb-Zr/Y-Y/Yb ( [19]) Fig.6 Zr/Nb-Zr/Y-Y/YbdiagramofmaficdikesinXinfeng ( 16.91),Zr/Hf 34.94~39.92( 37.62); Dy011 Nb/Ta 14.18~ Zr/Nb-Zr/ 20.57( 16.33),Zr/Hf 37.38~38.39 Y-Y/Yb ( 6), ( 37.77) 2 Nb/Ta Zr/Hf ( 17.5±2.0 36.27), (Mg # )(0.51~0.55)>0.4 ( 11 33) [22-23] Weav- er [24] Zhao [25],Nb/Ta Zr/Hf 6.3 w(σree) (La/ Yb) N, Yb,,, - 2 w(mgo) w(tfeo) w(tio 2 ), w(sio 2 ) w(al 2O 3 ) w(cao) Ti- Fe w(cao) CaO/ Al 2O 3, [26] Dy011 6.2 Eu, 6.4, Zr/Y-w(Zr) ( 7-a) Ti,Dy010,Dy011, w (Ti) ; [w(tio 2 )=1.39% ~1.62%], Th/Yb-Ta/Yb ( 7-b),Dy010, Th/Yb, WPB, Eu (δeu=0.85~1.05), ΣREE δeu, Th Zr/Nb-Zr/Y- [21] Y/Yb ( 6) 7 Zr/Y-w(Zr)(a)( [27]) Th/Yb-Ta/Yb(b)( [28]) Fig.7 DiscriminationdiagramsshowingZr/Y-Zr(a)andTh/Yb-Ta/Yb (b)ofmaficdikesinxinfeng
3 : 19 (Ba Rb K), Ta Nb Zr Hf [20] P Ta Hf Th,, Th/Yb,,Th/Ta Ta/Hf Th 2,, [29] Dy010, (148.6 Ma) (85.7 Th/Ta (3.70~5.10, 4.51) Ta/Hf (0.18~0.24), Dy011 : Th/Ta (1.84~2.27) Ta/Hf (0.23~0.29) (Th/Ta=1.6 ~4,Ta/Hf>0.1) Dy010 Dy011 Th/Ta (> 0.4), ( ) (Th/Ta>4, Ta/Hf=0.1~1), Th/Ta [30] - (140 Ma) - [3] 2 (148.6 Ma 85.7 Ma), 7 (1) (51):537-571. LA-ICP-MS U-Pb, SN NWW (148.6±4.1)Ma(MSWD = 1.3) (85.7±2.0)Ma(MSWD=1.4), (2) 2 ogycenter,2003., [(148.6±4.1)Ma] Ce 1-23. (δce=0.89~0.93) Eu (δeu =1.00~1.05); [(85.7±2.0) Ma] Ce (δce =0.66~0.82) Eu (δeu =0.85~1.02); (Ba Rb K), Ta Nb Zr Hf P (3) Ti-Fe (4) 2-2 [1],. [J].,1989,25(1):120-131. [2]. - [J]. :,1990(7): 747-755. [3],,. [J].,1997,26(2):14-31. [4],,,. [J].,2009,25(4):984-1000. [5],,,. 1 5 [R]. :,2016. [6] Liu Y S,HuZC,GaoS,etal.Insituanalysisofmajorand traceelementsofanhydrousmineralsbyla-icp-mswithout applyinganinternalstandard[j].chemical Geology,2008, 257:34-43. cling-induced melt-peridotiteinteractionsinthe Trans-North ChinaOrogen:U-Pbdating,Hfisotopesandtraceelementsin zirconsofmantlexenoliths[j].journalofpetrology,2010,55 [8] LiuY,HuZ,ZongK,etal.Reappraisementandrefinementof zirconu-pbisotopeandtraceelementanalysesbyla-icp-ms [J].ChineseScienceBuletin,2010,55(15):1535-1546. [9] AndersenT.CorrectionofcommonPbin U-Pbanalysesthat donotreport 204 Pb[J].ChemicalGeology,2002,192:59-79. ses[j].geostandardsand GeoanalyticalResearch,1995,19: [7] LiuY,GaoS,HuZ,etal.Continentalandoceaniccrustrecy- [10]Ludwig K R.ISOPLOT3.00:A geochronologicaltoolkitfor microsoftexcel[d].berkeley,california:berkeleygeochronol- [11] Wiedenbeck M,AleP,Corfu F,etal.Threenaturalzircon standardsforu-th-pb,lu-hf,traceelementandreeanaly- [12]SlámaJ,Ko lerj,condondj,etal.plesovicezircon-anew naturalreferencematerialforu-pbandhfisotopicmicroanal- ysis[j].chemicalgeology,2008,249 :1-35. [13]MiddlemostE A K.Namingmaterialsinthemagma/igneous rocksystem [J].Earth Science Reviews,1994,37 (3/4): 215-224. [14],. :I. - [J]. :,1997,27(6):488-493. [15]HiroseK,KushiroI.Partialmeltingofdryperidotitesathigh pressures:determinationofcompositionsofmeltssegregated fromperidotiteusingaggregatesofdiamond[j].earth and PlanetaryScienceLeters,1993,114(4):477-489. [16] Walter M J.Meltextractionandcompositionalvariabilityin
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