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Table Ig5-Hf
Lu, Yb and Hf LA-MC-ICPMS data of zircon crystals from sample GCH-20
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
A6_26_seq1 0
.0054 4 0.00026 2 1
.46704 1.88653 5 0.282854 35 0.282852 13.1 1.2 0.42 482 18 101 1
A7_40_seq1 0
.0053 5 0.00025 2 1
.46713 1.88685 11 0.282870 26 0.282867 14.2 0.9 0.37 455 18 90 1
A8_26_seq1 0.0275 47 0.00097 14 1.46700 1.88612 6 0.282858 31 0.282840 23.9 1.1 0.22 980 -
14 1
A9_26_seq1 0.0080 7 0.00037 3 1.46716 1.88627 5 0.282860 30 0.282856 13.0 1.1 0.41 469 10 100 1
A512_40_seq1 0.
0007 1 0.00002 0 1.
46716 1.88659 13 0.282831 26 0.282831 10.1 0.9 0.50 381 5 99 1
A519_40_seq1 0.0009 1 0.00003 0 1.46718 1.88674 12 0.282854 26 0.282853 11.4 0.9 0.45 404 6 100 1
A520_26_seq1 0
.0016 2 0.00005 0
1.46706 1.88611 7 0.282821 32 0.282821 10.4 1.1 0.51 410 7 100 1
A522_26_seq1 0.0005 0 0.00001 0 1.46713 1.88650 7 0.282814 39 0.282813 9.8 1.4 0.53 395 6 100 1
A525_26_seq1 0.0006 1 0.00002 0 1.46708 1.88637 6 0.282872 32 0.282872 12.1 1.1 0.41 404 7 100 1
A526_26_seq1 0.0004 0 0.00001 0 1.46705 1.88649 6 0.282858 32 0.282858 11.3 1.1 0.44 389 6 100 1
A528_40_seq1 0.0006 1 0.00002 0 1.46713 1.88659 12 0.282849 23 0.282849 10.9 0.8 0.46 389 6 100 1
A530_40_seq1 0.0005 0 0.00001 0 1.46712 1.88644 13 0.282815 24 0.282815 9.7 0.9 0.53 389 6 100 1
A543_40_seq1 0.0003 0 0.00001 0 1.46722 1.88680 15 0.282793 20 0.282793 9.0 0.7 0.57 390 6 99 1
A548_40_seq1 0.
0007 1 0.00002 0 1.
46716 1.88677 13 0.282817 23 0.282816 14.4 0.8 0.44 593 8 99 1
A559_40_seq1 0.0005 1 0.00002 0 1.46709 1.88640 12 0.282758 34 0.282758 7.7 1.2 0.64 386 5 100 1
A562_26_seq1 0
.0010 1 0.00003 0
1.46714 1.88659 6 0.282842 30 0.282842 10.9 1.1 0.47 401 6 100 1
A564_26_seq1 0.0003 0 0.00001 0 1.46711 1.88650 6 0.282785 31 0.282785 8.8 1.1 0.58 398 5 99 1
A575_26_seq1 0.0006 1 0.00002 0 1.46703 1.88626 6 0.282824 32 0.282824 10.3 1.1 0.51 399 7 99 1
A580_26_seq1 0.0004 0 0.00001 0 1.46707 1.88646 7 0.282798 30 0.282798 9.2 1.0 0.56 393 6 100 1
A590_26_seq1 0.0005 0 0.00001 0 1.46706 1.88614 6 0.282789 39 0.282789 8.9 1.4 0.58 391 6 100 1
A594_26_seq1 0
.0010 2 0.00003 1
1.46714 1.88622 6 0.282834 29 0.282834 10.4 1.0 0.49 390 5 99 1
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.
325