Kenichiro TANI*, Yuji ORIHASHI** and Setsuya NAKADA*** Abstract

No. 2,0-0,**, Technical Research Report, Earthquake Research Institute, University of Tokyo, No. 2, pp.,0-0,,**,. X : - 0 ++ ****** Major and Trace Components Analysis of Silicate Rocks by X-ray Fluorescence Spectrometer Using Fused Glass Beads : Evaluation of Analytical Precision of Three, Six, Eleven Times Dilution Fused Glass Beads Methods Kenichiro TANI*, Yuji ORIHASHI** and Setsuya NAKADA*** Abstract We established a quantitative analysis for +* major and +/ trace elements in silicate rocks by X-ray fluorescence spectrometry (XRF), using three types of dilution ratio glass bead, i.e., sample : flux ratios of + :,, + : / and + : +*. The individual calibration lines, constructed using,. igneous rock reference materials issued by USGS and GSJ, showed excellent accuracy and correlation coe$cient for both major and trace elements, and no di#erence among the three types of glass beads, but, overall, the low dilution glass bead method (+ :,) presented good analytical precision of both major and trace element in comparison with the other high dilution glass beads (+ : / and + : +*). For the assessment of our data quality, five reference rock materials of SY-,, SY--, MRG-+, MIN-L and NIM-G, issued by SABS and CANMET were measured using above low dilution glass bead method. Our results were in good agreement with the recommended values reported by Potts et al. (+33,), excluding Nb in SY-,, Co, Cr and Rb in SY--, Ba and Pb in MRG-+, and Co and Ni in NIM-G. This suggests that our XRF method using low dilution glass bead is suitable to rapid and accurate determination of major and trace elements in silicate rocks from single glass bead. Key words : X-ray fluorescence spectrometry, Low dilution glass bead, Silicate rock, Major and trace element determinations X XRF,**, 3.,**, +*,, * ** *** * Program for Geochemical Evolution, Institute for Frontier Research on Earth Evolution, Japan Marine Science & Technology Center, ** Division of Geodynamics, *** Volcano Research Center, Earthquake Research Institute, University of Tokyo. Norrish and Hutton, +303 ; Norrish and Chappell, +311 ; +311 ; +32* ; +32+ ; +32/ ; +321 ; +33- ; +33/ ; Enzweiler and Webb, +330 ; +331 26

X 27 +32+ ; +32+ ; +321 ; +321 ; +323 ; +33+ ; +33- a, b; +33- ; +330 ; +331 0 X - +33. ; Kimura and Yamada, +330 ; Tanaka and Orihashi, +331 ;,*** ;,**, X Tanaka and Orihashi, +331 X PW,.** - 0 ++ +* Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K, P +/ Sc, V, Cr, Co, Ni, Zn, Ga, Rb, Sr, Y, Zr, Nb, Ba, Pb, Th SABS South African Bureau of Standards CANMET Canada Centre for Mineral and Energy Technology SY-,, SY--, MRG-+, NIM-G SARM-+ NIM-L SARM- - / + - +33. +.2 g -.0 g Johnson Matthey Material Technology Spectroflux +**B ;Li,B. O 1 :,*, LiBO, : 2* *./. g ++*,. *.+ mg 3/ Pt-/ Au -* mmf NT-,+** +,*,.* 0** +,,** Aldrich Chemical /* mg,* JIS R,,+0 X JB-, JR-, 0 X RSD JB-, *.*3/ JR-, *.*// JIS R,,+0 RSD*.+ Z 2 wt s JB-, SiO, /-.,* wt *.+/, Fe,O - +..-. wt *.*/3, CaO 3.23 wt *.*// JR-, SiO, 1/.0/ wt *.+/, Al,O - +,.2, wt *.*-1 JIS R,,+0 Z.* s*.,, 2Z.* s*.+, 0 ++ 0 *.2 g..* g, ++ *.. g..* g + :, - 0 ++ +,* +2* -** +,+/* Aldrich Chemical /* mg 0 ++ JIS R,,+0 0 +33/

28 + X PW,.** Rh X,2 mmf Cu -* SuperQ Coltide Prop. K. Norrish,,*** ppm + Cu Cu, : SuperQ a ; CiDiEi* Ri+ n j+ aij* Cj ; Ci : i Ei : i Di : Ri : i net count rate, aij : i j a Cj : j : X X X +32+ SuperQ, : Rh X X X X * X XoaXb a, b X GSJ +/ JA-+, JA-,, JA--, JB-+, JB-+a, JB-,, JB--, JG-+, JG-+a, JG-,, JG--, JGb-+, JP-+, JR-+, JR-, USGS 3 BIR-+, DNC-+, DTS-+, G-,, QLO-+, RGM- +, SDC-+, STM-+, W-, - GSJ Imai et al. +33/ USGS Govindaraju +33.. ; CrC, n+ +, ; Cr : C: n: r ; r, CrCrmCCm, CrCrm, C Cm, ; Cr : Crm : C: Cm :. - 0 ++ Tanaka and Orihashi, +331 + Lower limit of detection : LLD Norrish and Chappell, +311 SuperQ ; LLD-*** n i+ai, RiTi +, ; ai : Ri :

+ X 29

30, kcps Ti : s i: / ++ -,- Sc, V, Ba Rh ScK a VK a Ba BaL a ++ Sc : /./ ppm, V 0./ ppm, Ba +3 ppm Imai et al. +33/ Sc JF-+ *.,- ppm JG-,,.., ppm JR-+ : /.*1 ppm V JF-+ /..- ppm JF-,..20 ppm JR-, -.** ppm Ba - 0 - JF-+ Sc, 0 JF-+ JG-, Sc JR-, V -

X 31. /, JA-+, JB-,, JR-, +* +* RSD 0 JA-+, JB-,, JR-, JA-+ Co, Th JR-, V - JA-+ MnO JB-, CaO -

32 0 ; RSD

X 33 0 ++ 0 ++ JA-+ TiO,,Al,O -, MnO, MgO, CaO, Na,O, K,O Zn, Sr Nb JB-, MnO P,O / Ga Y JR-, MnO P, O / ++ 0 + JA-+, JB-, JR-+ ; JB-, - Nb Pb RSD 0 0 Ni, Nb Pb ++ Ni, Rb, Nb Pb +* Th JA-+ - Ni Th RSD +* 0 Cr, Nb Th ++ Cr, Co Nb RSD +* Th Ni JR-, - V, Co Ni RSD 3 0 Sc, V + JB-,, JA-+ JR-, : - : 0 : ++

34 1

X 35 Cr RSD +* ++ +/ +* Zn, Ga, Rb, Sr, Y, Zr, Nb, Ba, Pb Th RSD +* Co Ni / - ; CANMET Canada Centre for Mineral and Energy Technology SY-, Syenite SY-- Syenite MRG-+ Gabbro SABS South Africa Bureau of Standards NIM-G SARM-+ ; Granite NIM-L SARM-- ; Lujaurite Potts et al. +33, 1 NIM-G NIM-L MgO MGR-+ P, O /,*.* Ga, Sc, Sr, V, Y, Zn Zr / Th MIR-+. 0,. SY-, SY-- Rb ++-- Pb ++.* SY-, Nb, SY-- Co Cr, MRG-+ Ba, NIM-G Co Ni,* Ba, Co. Cr, Nb, Ni, Pb Rb NIM-L Zn, Ga, Sr, Zr, Nb Pb Sr 1** ppm 0 Zr +,,+* ppm 2 - +, Th Th X PW,.** - 0 ++,/ GSJ USGS,. - - LLD RSD ++ +* / SY-,, SY--, MRG-+, NIM-L NIM-G - SY-, Nb, SY-- Cr, Co Rb, MRG-+ Ba Pb, NIM-G Co Ni : XRF XRF Enzweiler, J. and P.C. Webb, +330, Determination of trace elements in silicate rocks by X-ray fluorescence spectrometry on + : / glass disc : comparison of accuracy and precision with pressed powder pellet analysis, Chem. Geol., +-*, +3/,*,. +32+ X + -,,+-,,0.,**, XRF -+ +0, +1-. +33+ X I,,,2.+. Govindaraju, K., +33., Special Issue +33. complication of

36 working valued and sample description for -2- geostandard, Geostand. Newslett., +2, ++/2. +330 Rh X,,1-0. +321 X Rh 0 +0++03. Imai, N., S. Terashima, S. Ithoh and A. Ando, +33/, +33. complication values for GSJ reference samples, Igneous rock series, Geochem. J.,,3, 3+3/. +323 X,-.-/.. Kimura, J. and Y. Yamada, +330, Evaluation of major and trace element XRF analyses using a flux to sample ratio of two to one glass bead, J. Min. Petr. Econ. Geol., 3+, 0,1,.,*** X,3 +*1+,/. +32+ X +/ ++/+,.. +32* X 1/,1,,12. +33- X 2-1/*. +33. X 23 +.1+.2. +321 X, +/ +,1... +32/ X +. - +*-++/. Norrish, K. and J.T. Hutton, +303, An accurate X-ray spectrographic method for the analysis of a wide range of geological samples, Geochem. Cosmochim. Acta, --,.-+./-. Norrish, K. and B.W. Chappell, +311, X-ray fluorescence spectrometry, in Physical Methods in Determinative Mineralogy,nd Ed., J. Zussman, ed., Academic Press, London,,*+,1,. +321 Rh X -2 /102. +33/ X Cr JIS R,,+0 IGGE SABS Tech. Rep. ISEI, Ser. B, +/, ++1. +33- a X + Tech. Rep. ISEI, Ser. B, +,, +,,. +33- b X, Tech. Rep. ISEI, Ser. B, +-, +,3. Potts, P. J., A.G. Tindle and P.C. Webb, +33,, Geochemical reference material composition, CRC Press Inc., U.S.A., -+p. +311 X 2-1,/1--. +32+ X 21 01/022. Tanaka, R. and Y. Orihashi, +331, XRF analysis of major and trace elements for silicate rocks using low dilution ratio fused glass, HUPS Tech. Rep.,,, +,*. +331 3, -3+.*3.