微量元素的地球化學(xué)分類

1、感謝中國(guó)地質(zhì)大學(xué)（武漢）劉勇勝老師部分課件巖漿巖中主要造巖礦物和副礦物的分子式巖漿巖中主要造巖礦物和副礦物的分子式Q/Qtz石 英 QuartzSiO2Kf 鉀長(zhǎng)石 OrthoclaseKAlSi3O8Ab鈉長(zhǎng)石 AlbiteNaAlSi3O8An鈣長(zhǎng)石 AnorthiteCaAl2Si2O8Ne霞 石 Nepheline NaAlSiO4Bi黑云母 BiotiteK2Fe6Si6Al2O20(OH)2Hb/Amp角閃石 Hornblende(Ca,Na)23(Mg,Fe2+,Fe3+,Al)5(Al,Si)4O112(OH)2Cpx透輝石 DioriteCaMgSi2O6Opx紫蘇輝石Ort

2、hopyroxene (Mg,Fe)2Si2O6Ol橄欖石 Olivine(Mg,Fe)2SiO4Mt磁鐵礦 MagnetiteFe3O4Ilm鈦鐵礦 IlmaniteFeTiO3Ap磷灰石 ApatiteCa5PO43(F,Cl,OH)Sph/Ti榍 石 TitaniteCaTiSiO4(O,OH,Cl,F)Sp尖晶石 SpinelMgAl2O4Grt石榴石 Garnet(Fe,Mg,Ca)3Al2Si3O12Zr鋯 石 Zircon ZrSiO4v Gast（1968）不作為體系中任何相的組分存在的元素）不作為體系中任何相的組分存在的元素v 伯恩斯（晶體場(chǎng)理論的礦物學(xué)應(yīng)用）只要某元素在體系

3、中的伯恩斯（晶體場(chǎng)理論的礦物學(xué)應(yīng)用）只要某元素在體系中的含量低到可以用稀溶液定律來描述其行為，即可稱微量元素含量低到可以用稀溶液定律來描述其行為，即可稱微量元素v 微量元素的概念是相對(duì)的微量元素的概念是相對(duì)的 K：花崗巖中常量元素，超基性巖中微量元素：花崗巖中常量元素，超基性巖中微量元素 Ni：地殼巖石中微量元素，隕石中常量元素：地殼巖石中微量元素，隕石中常量元素 Li，B：偉晶巖中常量元素：偉晶巖中常量元素v 對(duì)于地殼，對(duì)于地殼，O，Si，Al，F(xiàn)e，Mg，Ca，Na，K，Ti常量元素，常量元素，其他是微量元素其他是微量元素 （1）Si，酸度，基性中性酸性，巖石分類，酸度，基性中性酸性，巖石

4、分類 （2）K, Na，堿度，巖漿系列，堿度，巖漿系列 （3）Mg, Fe, Mn， （4）Al， （5）Ca獨(dú)立礦物獨(dú)立礦物 U ZrSiO4類質(zhì)同像替代類質(zhì)同像替代 ! Sr、Eu Ca Pb、Ba KMgNi晶格缺陷晶格缺陷吸附吸附 In the classification scheme of Goldschmidt, elements are divided according to how they partition between coexisting silicate liquid, sulfide liquid, metallic liquid, and gas phase

5、defined by examining ore smelting slags and meteorites硫化物流體金屬流體氣相親鐵元素親銅/硫元素親石元素親氣元素H, He, N, Noble gasesAlkalis, Alkaline Earths, Halogens, B, O, Al, Si, Sc, Ti, V, Cr, Mn, Y, Zr, Nb, Lanthanides, Hf, Ta, Th, UCu, Zn, Ga, Ag, Cd, In, Hg, Tl, As, S, Sb, Se, Pb, Bi, TeFe, Co, Ni, Ru, Rh, Pd, Os, Ir, P

6、t, Mo, Re, Au, C, P, Ge, Sn Melting a chondrite gives 3 immiscible liquids plus vapor:硅酸鹽流體What makes an element siderophile or lithophile? Notably, the Goldschmidt categories are well-grouped in the periodic table of the elements:HLiNaKRbCsFrBeMgCaSrBaRaScYTiZrHfRfVNbTaDbCrMoWSgMnTcReBhFeRuOsHsCoRh

7、IrMtNiPdPtCuAgAuZnCdHgGaInTlGeSnPbAsSbBiSeTePoBrIAtKrXeRnBAlCSiNPOSFClNeArHeLaAcCeThPrPaNdUPmNpSmPuEuAmGdCmTbBkDyCfHoEsErFmTmMdYbNoLuLr1234567IAIIAIIIA IVAVAVIAVIIA VIIIAIIIB IVBVBVIBVIIBVIIIBIBIIBLanthanidesActinides13111937558741220385688213922407210423417310524427410625437510726447610827457710928

8、4678294779304880513314981614325082715335183816345284917355385101836548625789589059916092619362946395649665976698679968100691017010271103AtmophileLithophileChalcophileSiderophileArtificialiiDDRT/ )(iiiiiiiiiiiiiiaaK)P,T(KebbRTlnbRTlnbRTlnbRTlnbii微量元素地質(zhì)溫度微量元素地質(zhì)溫度計(jì)和地質(zhì)壓力計(jì)計(jì)和地質(zhì)壓力計(jì)K* = K2O/(K2O + Al2O3)摩爾數(shù)

9、之比Horng W.S. and Hess P.S., CMP, (2000) 138: 176-185Seitz et al.(1999), GCA, 63: 39673982,橄欖巖中過渡元橄欖巖中過渡元素在素在cpxcpx和和opxopx之之間的分配系數(shù)隨間的分配系數(shù)隨溫度的變化溫度的變化K = DK = Dcpxcpx/D/Dopxopx= = C Ccpxcpx/C/CopxopxNimis P., Taylor W.R., 2000. CMP, 139: 541-554.單斜輝石中單斜輝石中CrCr的的分配系數(shù)隨壓力分配系數(shù)隨壓力的變化的變化 AB12nijjiDiKDOlivin

10、eOpxCpxGarnetPlagAmph MagnetiteRb0.0100.0220.0310.0420.0710.29 Sr0.0140.0400.0600.0121.8300.46 Ba0.0100.0130.0260.0230.230.42 Ni14570.9550.016.829Cr0.7010341.3450.012.007.4La0.0070.030.0560.0010.1480.5442Ce0.0060.020.0920.0070.0820.8432Nd0.0060.030.2300.0260.0551.3402Sm0.0070.050.4450.1020.0391.8041

11、Eu0.0070.050.4740.243 0.1/1.5*1.5571Dy0.0130.150.5821.9400.0232.0241Er0.0260.230.5834.7000.0201.7401.5Yb0.0490.340.5426.1670.0231.6421.4Lu0.0450.420.5066.9500.0191.563Data from Rollinson (1993).* Eu3+/Eu2+Italics are estimatedRare Earth ElementsDifjjDij/meltOlivineOpxCpxGarnetPlagAmph MagnetiteRb0.0

12、100.0220.0310.0420.0710.29 Sr0.0140.0400.0600.0121.8300.46 Ba0.0100.0130.0260.0230.230.42 Ni14570.9550.016.829Cr0.7010341.3450.012.007.4La0.0070.030.0560.0010.1480.5442Ce0.0060.020.0920.0070.0820.8432Nd0.0060.030.2300.0260.0551.3402Sm0.0070.050.4450.1020.0391.8041Eu0.0070.050.4740.243 0.1/1.5*1.5571

13、Dy0.0130.150.5821.9400.0232.0241Er0.0260.230.5834.7000.0201.7401.5Yb0.0490.340.5426.1670.0231.6421.4Lu0.0450.420.5066.9500.0191.563Data from Rollinson (1993).* Eu3+/Eu2+Italics are estimatedRare Earth Elements特例特例Crystallizing Minerals Ni is compatible (KD 1) in olivine. Olivine crystallization depl

14、etes residual magmas in Ni. Zr is incompatible (KD 1). Residual magmas are continuously enriched in Zr. 0.002.004.006.008.0010.00565860626466687072sample/chondrite La Ce Nd Sm Eu Tb Er Yb Lu57% Ol 14% Opx 14% Cpx 14% Grt0.002.004.006.008.0010.00565860626466687072sample/chondrite La Ce Nd Sm Eu Tb Er

15、 Yb Lu67% Ol 17% Opx 14% Cpx 3% Sp0.002.004.006.008.0010.00sample/chondrite60% Ol 15% Opx 15% Cpx 10%Plag La Ce Nd Sm Eu Tb Er Yb LuDepth of melting from REE patterns Tectonic Setting from distinctive trace element patterns Multi-Element Diagrams A和和B哪一個(gè)反映（哪一個(gè)反映（A）分餾結(jié)晶作用）分餾結(jié)晶作用程度增加的方向，哪一個(gè)反映部分（程度增加的方

16、向，哪一個(gè)反映部分（B）熔融作用程度增加的方向？熔融作用程度增加的方向？AB？12Eu2+Ce4+OlivineOpxCpxGarnetPlagAmph MagnetiteRb0.0100.0220.0310.0420.0710.29 Sr0.0140.0400.0600.0121.8300.46 Ba0.0100.0130.0260.0230.230.42 Ni14570.9550.016.829Cr0.7010341.3450.012.007.4La0.0070.030.0560.0010.1480.5442Ce0.0060.020.0920.0070.0820.8432Nd0.0060.

17、030.2300.0260.0551.3402Sm0.0070.050.4450.1020.0391.8041Eu0.0070.050.4740.243 0.1/1.5*1.5571Dy0.0130.150.5821.9400.0232.0241Er0.0260.230.5834.7000.0201.7401.5Yb0.0490.340.5426.1670.0231.6421.4Lu0.0450.420.5066.9500.0191.563Rare Earth ElementsREE mineralmelt partition coefficients formafic magmas.相容性增

18、強(qiáng)相容性增強(qiáng)原子數(shù)增加原子數(shù)增加-3-2-1012345678910110102030405060708090100Atomic Number (Z)Log (Abundance in CI Chondritic Meteorite)HHeLiBeBCNOFScFeNiNeMgSiSCaArTiPbPtSnBaVKNaAlPClThUREE5758596062636465666768697071LaCePrNdSmEuGdTbDyHoErTmYbLu0.1110Concentration (ppm)LaCePrNdSmEuGdTbDyHoErTmYbLu0.1110Concentration (ppm)LaCePrNdSmEuGdTbDyHoErTmYbLu0.1110Chondrite-Normalized ValueLaCePrNdSmEuGdTbDyHoErTmYbLu0.1110Co