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Table Ig7-Hf
Lu, Yb and Hf LA-MC-ICPMS data of zircon crystals from sample GCH-23
176
Yb
a
176
Lu
a
178
Hf
180
Hf Sig
Hf
b 176
Hf
176
Hf
d
ı
c
T
DM
e
age
f
ı U-Pb
g
Lu-Hf
h
177
Hf
177
Hf
177
Hf
177
Hf
(V)
177
Hf
177
Hf
(t)
İ+I (Ga) (Ma) (Ma) conc seq
A113_seq3_26 0.0145 30 0.00052 8 1.46707 1.88595 7 0.282616 47 0.282611 5.0 1.7 0.88 503 7 99 3
A115_seq3_40 0.0115 15 0.00043 4 1.46714 1.88619 12 0.282598 28 0.282594 4.3 1.0 0.92 495 7 98 3
A116_seq3_26 0.0123 25 0.00045 6 1.46655 1.88347 5 0.282324 78 0.282320 -5.3 2.8 1.45 502 8 99 3
A117_seq3_26 0.0403 59 0
.00135 17 1.46700
1.88568 5 0.282589 57 0.282576 4.4 2.0 0.94 527 7 98 3
A121_seq3_26 0.0156 18 0.00055 5 1.46712 1.88627 6 0.282638 43 0.282633 5.6 1.5 0.84 491 7 95 3
A123_seq3_26 0.0158 34 0.
00047 10 1.46693 1.
88616 6 0.282567 43 0.282563 2.6 1.5 0.99 470 5 95 3
A124_seq3_26 0.0270 40 0.00087 11 1.46707 1.88569 6 0.282614 92 0.282606 4.4 3.3 0.90 480 7 96 3
A126_seq3_18 0.0202 42 0.00068 13 1.46705 1.88597 4 0.282733 40 0.282728 6.5 1.4 0.70 381 292 127 3
A129_seq3_26 0
.0077 7 0.00026 2
1.46709 1.88633 7 0.281534 40 0.281526 -8.0 1.4 2.52 1624 61 52 3
A130_seq3_26 0.0529 92 0
.00161 26 1.46684
1.88542 6 0.282540 71 0.282527 0.8 2.5 1.07 448 9 105 3
A131_seq3_26 0
.0071 6 0.00028 2
1.46711 1.88592 6 0.282611 37 0.282608 5.1 1.3 0.88 507 7 99 3
A132_seq3_26 0.0151 20 0.00053 6 1.46713 1.88662 7 0.282669 29 0.282663 9.7 1.0 0.72 629 83 77 3
A133_seq3_26 0.0172 15 0.00059 4 1.46718 1.88642 7 0.282679 34 0.282673 7.6 1.2 0.75 519 52 88 3
A134_seq3_26 0.0200 50 0.
00063 15 1.46709 1.
88624 7 0.282679 29 0.282673 7.4 1.0 0.75 510 7 98 3
A135_seq3_26 0.0336 31 0
.00126 10 1.46706
1.88596 6 0.282328 51 0.282313 -3.0 1.8 1.42 615 11 101 3
A136_seq3_26 0.0170 21 0.00054 6 1.46711 1.88685 6 0.282568 105 0.282559 12.3 3.7 0.81 908 91 56 3
A137_seq3_26 0.0216 26 0.
00073 7 1.46706 1.
88625 6 0.282614 32 0.282608 4.3 1.1 0.90 474 7 96 3
A139_seq3_26 0.0122 11 0.00038 2 1.46710 1.88638 6 0.282618 50 0.282614 6.4 1.8 0.85 559 118 86 3
A142_seq3_26 0.0340 62 0
.00108 17 1.46705
1.88587 6 0.282664 40 0.282654 6.2 1.4 0.80 485 7 97 3
A144_seq3_40 0.0484 41 0
.00161 10 1.46719
1.88657 13 0.282676 28 0.282662 6.4 1.0 0.79 481 6 102 3
A145_seq3_26 0
.0072 6 0.00031 2
1.46713 1.88615 5 0.282661 36 0.282658 6.8 1.3 0.79 507 8 100 3
A151_seq3_26 0.0106 10 0.00041 3 1.46699 1.88586 5 0.282620 38 0.282617 4.5 1.3 0.88 468 8 102 3
A154_seq3_26 0.0220 38 0.
00074 10 1.46704
1.88630 7 0.282622 55 0.282615 5.0 1.9 0.88 492 7 98 3
A159_seq3_26 0.0244 54 0.
00076 16 1.46698
1.88582 7 0.282604 49 0.282597 4.3 1.7 0.91 491 7 98 3
A163_seq3_26 0.0345 35 0
.00120 10 1.46701
1.88613 7 0.282622 27 0.282611 5.3 0.9 0.88 513 7 102 3
Grain
ı
ı
±2ı
c
İ+I
(t)
d
Quoted uncertainties (absolute) relate to the last quoted figure. The effect of the inter-element fractionation on Lu/Hf was estimated to be about 6 % or less
based on analyses of the GJ-ϭ ĂŶĚ WůĞƐŽǀŝēĞ njŝƌĐŽŶ͘ ĐĐƵƌĂĐLJ ĂŶĚ ƌĞƉƌŽĚƵĐŝďŝůŝƚLJ ǁĂƐ ĐŚĞĐŬĞĚ ďLJ ƌĞƉĞĂƚĞĚ ĂŶĂůLJƐĞƐ ŽĨ ƌĞĨĞƌĞŶĐĞ njircon GJ-ϭ ĂŶĚ WůĞƐŽǀŝēĞ
(data given as mean with 2 standard deviation uncertainties).
(a)
176
Yb/
177
Hf = (
176
Yb/
173
Yb)
true
x (
173
Yb/
177
Hf)
meas
x (M
173(Yb)
/M
177(Hf)
)
ɴ;,ĨͿ
͕ ɴ;,ĨͿ с ůŶ;;
179
Hf/
177
Hf
true
)/(
179
Hf/
177
Hf
measured
)) / ln(M
179(Hf)
/M
177(Hf)
), M = mass of
respective isotopes. The
176
Lu/
177
Hf was calculated in a similar way using
175
Lu/
177
,Ĩ ĂŶĚ ɴ;zďͿ͘
(b)
Mean Hf signal in volts.
(c)
Uncertainties are quadratic additions of the within-run precision and the daily reproducibility of the 40ppb-JMC475 solution. Uncertainties for the JMC475
quoted at 2SD (2 standard deviation).
(d)
Initial
176
Hf/
177
,Ĩ ĂŶĚ ɸ,Ĩ ĐĂůĐƵůĂƚĞĚ ƵƐŝŶŐ ƚŚĞ ĂƉƉĂƌĞŶƚ h-Pb age determined by LA-ICP-MSdating (see column f), and the CHUR parameters:
176
Lu/
177
Hf =
0.0336, and
176
Hf/
177
Hf = 0.282785 (Bouvier et al. 2008).
(e)
Two stage model age in Ga using measured
176
Lu/
177
Lu of each spot (first stage = age of zircon), a value of 0.0113 for the average continental crust (second
stage, values compiled from Rudnick and Gao (2003), and depleted mantle
176
Lu/
177
Lu = 0.0379, and
176
Hf/
177
Hf = 0.283164.
(f)
Apparent U-Pb age determined by LA-ICP-MS.
(g)
U-Pb age concordance (%).
(h)
Sequence in which Lu-Hf analyses were performed. Standard analyses for each sequence are showed on Table 12.
327