Wedepohl(1995)による〔『The composition of the continental crust』（1219-1221p）から〕

『Abstract
　A new calculation of the crustal composition is based on the proportions of upper crust (UC) to felsic lower crust (FLC) to mafic lower crust of about 1:0.6:0.4. These proportions are derived from a 3000 km long refraction seismic profile through western Europe (EGT) comprising 60％ old shield and 40％ younger fold belt area with about 40 km average Moho depth. A granodioritic bulk composition of the UC in major elements and thirty-two minor and trace elements was calculated from the Canadian Shield data (Shaw et al., 1967, 1976). The computed abundance of thirty-three additional trace elements in the UC is based on the following proportions of major rock units derived from mapping: 14％ sedimentary rocks, 25％ granites, 20％ granodiorites, 5％ tonalites, 6％ gabbros, and 30％ gneisses and mica schists. The composition of FLC and MLC in major and thirty-six minor and trace elements is calculated from data on felsic granulite terrains and mafic xenoliths, respectively, compiled by Rudnick and Presper (1990). More than thirty additional trace element abundances in FLC and MLC were computed or estimated from literature data.
　The bulk continental crust has a tonalitic and not a dioritic composition with distinctly higher concentrations of incompatible elements including the heat producing isotopes in our calculation. A dioritic bulk crust was suggested by Taylor and McLennan(1985). The amount of tonalite in the crust requires partial melting of mafic rocks with about 100 km thickness (compared with about 7 km in the present MLC) and water supply from dehydrated slabs and mafic intrusions. At the relatively low temperatures of old crustal segments MLC was partly converted into eclogite which could be recycled into the upper mantle under favourable tectonic conditions. The chemical fractionation of UC against FLC + MLC was caused by granitoidal partial melts and by mantle degassing which has controlled weathering and accumulation of volatile compounds close to the Earth's surface.』

Former estimates of crustal composition; seismic crustal model

『
表1　大陸上部地殻（UC）と大陸下部地殻（LC）の元素濃度（ppm）（参考文献は表2の脚注を参照）
　 UC LC UC/LC 　 UC LC UC/LC 　 UC LC UC/LC
Si 303480 271330 1.1 Ce 65.7 53.1 1.2 Yb 1.5 2.5 0.60
Al 77440 82120 0.94 Ni 18.6 99 0.19 U 2.5 0.93 2.7
Fe 30890 57060 0.54 Nd 25.9 28.1 0.92 Br 1.6 0.28 5.7
Ca 29450 48600 0.61 La 32.3 26.8 1.2 Ge 1.4 (1.4) 1.0
Na 25670 21200 1.2 Cu 14.3 37.4 0.38 Be 3.1 1.7 1.8
Mg 13510 31550 0.43 Co 11.6 38 0.31 Mo 1.4 0.6 2.3
K 28650 13140 2.2 Y 20.7 27.2 0.76 Eu 0.95 1.6 0.59
Ti 3117 5010 0.62 Nb 26 11.3 2.3 Ta 1.5 0.84 1.8
C 3240 588 5.5 Li 22 13 1.7 I 1.4 0.14 10
P 665 872 0.75 Sc 7 25.3 0.28 Ho 0.62 0.99 0.63
Mn 527 909 0.57 Ga 14 17 0.82 W 1.4 0.6 2.3
S 953 408 2.3 Pb 17 12.5 1.4 Tb 0.50 0.81 0.62
Ba 668 568 1.2 B 17 5 3.4 Tl 0.75 0.26 2.9
F 611 429 1.4 Th 10.3 6.6 1.6 Lu 0.27 0.43 0.63
Cl 640 278 2.3 Pr 6.3 7.4 0.85 Sb 0.31 0.30 1.0
Sr 316 352 0.90 Sm 4.7 6.0 0.78 Cd 0.102 0.101 1.0
Zr 237 165 1.4 Hf 5.8 4.0 1.5 Ag 0.055 0.080 0.69
Cr 35 228 0.15 Gd 2.8 5.4 0.52 Bi 0.123 0.037 3.3
V 53 149 0.36 Dy 2.9 4.7 0.62 Se 0.083 0.170 0.47
Rb 110 41 2.7 Sn 2.5 2.1 1.2 In 0.061 0.052 1.2
Zn 52 79 0.66 Cs 5.8 0.8 7.3 Hg 0.056 0.021 2.7
N 83 34 2.4 As 2.0 1.3 1.5

　　

表2　大陸地殻の元素濃度（酸化物としての主要元素濃度は表3を参照、引用文献は脚注を参照）
元素名 濃度 単位 脚注 元素名 濃度 単位 脚注 元素名 濃度 単位 脚注
O 47.2

％
 a Nd 27

ppm
 a Mo 1.1

ppm
 o
Si 28.8 a Cu 25 a Br 1.0 p
Al 7.96 a Co 24 a W 1.0 q
Fe 4.32 a Y 24 a I 800

ppb
 r
Ca 3.85 a Nb 19 a Ho 800 a
Na 2.36 a Li 18 a Tb 650 a
Mg 2.20 a Sc 16 a Tl 520 s
K 2.14 a Ga 15 a Lu 350 a
Ti 4010

ppm
 a Pb 14.8 a Tm 300 g
C 1990 b B 11 f Sb 300 t
P 757 a Th 8.5 a Se 120 u
Mn 716 a Pr 6.7 g Cd 100 s
S 697 b Sm 5.3 a Bi 85 s
Ba 584 c Hf 4.9 a Ag 70 v
F 525 d Gd 4.0 a In 50 w
Cl 472 d Dy 3.8 g Hg 40 x
Sr 333 a Cs 3.4 h Te (5) y
Zr 203 a Be 2.4 i Au 2.5 z
Cr 126 a Sn 2.3 k Pd 0.4 aa
V 98 a Er 2.1 g Pt 0.4 aa
Rb 78 a Yb 2.0 a Re 0.4 bb
Zn 65 a As 1.7 l Ru 0.1 aa
N 60 e U 1.7 a Rh 0.06 aa
Ce 60 a Ge 1.4 m Os 0.05 bb
Ni 56 a Eu 1.3 a Ir 0.05 aa
La 30 a Ta 1.1 n

　　

UC＝上部地殻、LC＝下部地殻
a UC: Shaw et al.(1967, 1976), LC: Rudnick and Presper(1990) in the proportions of Fig.2
b Fig.7
c UC: calculated from rock averages compiled by Puchelt(1972) in the proportions of Fig.2, LC: Rudnik and Presper(1990})
d UC: calculated from rock averages compiled by Wedepohl(1987) in the proportions of Fig.2, LC: averages of granulites and gabbro
e UC, LC: calculated from rock averages compiled by Wlotzka(1972) in the proportions of Fig.2 (additional data on granites Hall, 1988)
f UC: calculated from rock averages compiled by Harder(1974) and Shaw et al.(1986) in the proportions of Fig.2, LC: data from Truscott et al.(1986), Leema et al.(1992) and Harder(1974)
g interpolated from smooth curve of chondrite normalized REE distribution in the continental crust
h UC: Rb/19 according to Mcdonough et al.(1992), LC: Rudnick and Presper(1990)
i UC: calculated from rock averages compiled by Hoermann(1969) in the proportions of Fig.2, LC: Sighinolfi(1973)
k UC: calculated from rock averages compiled by Hamaguchi and Kuroda(1969) and Smith and Burton(1972) in the proportions of Fig.2, LC: Rudnick and Presper(1990)
l UC: calculated from rock averages of Onishi and Sandell(1955), Burwash and Culbert(1979) in the proportions of Fig.2, LC: gabbro, gneiss minus 20％ granite
m UC: calculated from rock averages compiled by Hoermann(1970) and Onishi(1956) in the proportions of Fig.2, LC: gneiss, gabbro
n UC: calculated from Nb/Ta=17.5 (from international reference rocks) Gladney et al.(983), LC: Rudnick and Presper(1990)
o UC: calculated from rock averages compiled by Manheim and Landergren(1978) in the proportions of Fig.2, gabbro, gneiss minus 20％ granite
p UC, LC: calculated from rock averages compiled by Fuge(1974a) (partly corrected with Cl/Br ratio 1000) in the proportions of Fig.2. sedimentary rocks calculated with Cl/Br=290 (seawater)
q UC, LC: calculated from rock averages compiled by Krauskopf(1970) in the proportions of Fig.2
r UC: calculated from rock averages compiled by Fuge(1974b) and Becker et al.(1972) in the proportions of Fig.2 considering accumulation in Corg rich sediments (C/I correlation of Price et al., 1970), LC: estimated
s UC, LC: calculated from rock averages of Heinrichs et al.(1980) in the proportions of Fig.2
t UC: calculated from rock averages of Onishi and Sandell(1955) and Burwash and Culbert(1979) in the proportions of Fig.2, LC: estimated
u UC, LC: calculated from rock averages of Koljonen(1973) and Keltsch(1983) in the proportions of Fig.2, S/Se in crustal rocks except sediments: 8.5×103
v UC, LC: calculated from rock averages of Hamaguchi and Kuroda(1959) in the proportions of Fig.2, Cu/Ag in felsic rocks 300 to 450
w UC, LC: calculated from rock averages compiled by Linn and Schmitt(1972) and contributed by Voland(1969) in the proportions of Fig.2
x UC, LC: calculated from rock averages compiled by the present author partly from Marowski and Wedepohl(1971) and partly from unpublished data of Heinrichs in the proportions of Fig.2
y UC, LC: order of magnitude estimated from data on international reference rocks (Gladney et al., 1983, Sighinolfi et al., 1979) and on MORB (Hertogen et al., 1990)
z UC: calculated from rock averages compiled by Crocket(1974) in the proportions of Fig.2, LC: partly from Sighinolfi and Santos(1976) partly from gabbro
aa UC, LC: from composite sample of 17 European greywackes analysed by ICP MASS in nickel sulfide extract after Te oprecipitation (Hartmann, 1995)
bb UC: Esser and Turekian(1993)
』

Crustal concentrations of major elements and commonly analysed minor elements
Crustal concentrations of rarely analysed elements
Genetic implications
References

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