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Table Ig6-Hf
Lu, Yb and Hf LA-MC-ICPMS data of zircon crystals from sample GCH-22
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
A361_40_seq2 0.0175 14 0.00059 4 1.46718 1.88687 12 0.282471 21 0.282466 -0.6 0.8 1.17 481 7 99 2
A362_40_seq2 0.0110 9 0.00041 3 1.46720 1.88676 13 0.282462 21 0.282458 -0.7 0.7 1.19 487 7 93 2
A363_40_seq2 0.0083 7 0.00032 2 1.46724 1.88667 12 0.282492 27 0.282489 0.1 0.9 1.13 474 7 99 2
A364_40_seq2 0.0165 14 0.00054 3 1.46716 1.88657 11 0.282433 24 0.282428 -1.9 0.8 1.25 482 8 97 2
A368_40_seq2 0.0117 9 0.00041 2 1.46719 1.88685 12 0.282469 26 0.282465 -0.8 0.9 1.18 474 7 96 2
A369_40_seq2 0.0117 10 0.00040 3 1.46717 1.88673 12 0.282475 22 0.282471 -0.5 0.8 1.17 474 7 98 2
A370_40_seq2 0.0214 17 0.
00070 4 1.46718 1.
88666 13 0.282445 23 0.282439 -1.8 0.8 1.23 468 7 97 2
A374_40_seq2 0.0174 14 0.00058 3 1.46719 1.88678 13 0.282452 20 0.282447 -1.3 0.7 1.21 477 7 99 2
A378_40_seq2 0.0135 11 0.00046 3 1.46717 1.88676 13 0.282448 23 0.282444 -1.6 0.8 1.22 469 7 97 2
A379_40_seq2 0.0133 11 0.00046 3 1.46713 1.88670 12 0.282435 23 0.282431 -1.6 0.8 1.24 491 7 100 2
A380_40_seq2 0.0151 12 0.00051 3 1.46718 1.88670 13 0.282468 22 0.282463 -1.1 0.8 1.19 463 7 94 2
A381_40_seq2 0.0131 10 0.00045 3 1.46719 1.88681 12 0.282454 19 0.282450 -1.0 0.7 1.20 488 7 98 2
A388_40_seq2 0.0149 12 0.00051 3 1.46719 1.88685 12 0.282477 25 0.282473 -0.4 0.9 1.16 477 7 95 2
A389_40_seq2 0.0148 12 0.00051 3 1.46720 1.88697 12 0.282488 21 0.282483 -0.2 0.8 1.14 469 7 94 2
A392_40_seq2 0
.0092 7 0.00032 2 1
.46720 1.88668 12 0.282473 21 0.282471 -0.9 0.7 1.17 457 7 92 2
A407_40_seq2 0
.0093 8 0.00032 2 1
.46722 1.88688 12 0.282500 23 0.282497 0.5 0.8 1.11 480 7 98 2
A416_40_seq2 0
.0078 6 0.00027 2
1.46718 1.88678 13 0.282456 19 0.282454 -1.0 0.7 1.20 481 7 100 2
A419_40_seq2 0
.0094 8 0.00035 2 1
.46710 1.88668 13 0.282470 19 0.282466 0.0 0.7 1.16 506 8 100 2
A422_40_seq2 0.0118 9 0.00041 2 1.46719 1.88680 12 0.282464 21 0.282461 -1.7 0.8 1.20 438 6 101 2
A438_40_seq2 0.0002 0 0.00000 0 1.46717 1.88677 14 0.282627 22 0.282627 -5.6 0.8 1.05 0 0 0 2
A444_40_seq2 0.0006 1 0.00001 0 1.46713 1.88663 14 0.282631 22 0.282630 23.0 0.8 0.50 1267 221 28 2
A445_40_seq2 0.0004 0 0.00001 0 1.46717 1.88661 15 0.282618 20 0.282618 3.0 0.7 0.91 398 15 105 2
A446_40_seq2 0
.0011 3 0.00002 1
1.46666 1.88319 7 0.282375 108 0.282375 -14.5 3.8 1.54 0 0 0 2
A448_40_seq2 0.0002 0 0.00001 0 1.46716 1.88643 19 0.282612 19 0.282612 -6.1 0.7 1.08 0 0 0 2
A450_40_seq2 0.
0001 0 0.00000 0 1.
46712 1.88643 14 0.282601 26 0.282601 -6.5 0.9 1.10 0 0 0 2
A451_40_seq2 0.0002 0 0.00001 0 1.46717 1.88665 14 0.282617 19 0.282617 2.8 0.7 0.91 393 9 99 2
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.
326