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Table Ig13-Hf
Lu, Yb and Hf LA-MC-ICPMS data of zircon crystals from sample GCH-31
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
GCH-31_220 0.0409 42 0
.00139 12 1.46713
1.88641 5 0.282421 32 0.282408 -2.4 1.1 1.28 493 7 92 6
GCH-31_219 0.0382 32 0
.00127 8 1.46717
1.88678 5 0.282466 40 0.282455 -1.0 1.4 1.20 480 7 91 6
GCH-31_218 0.0458 45 0
.00159 13 1.46715
1.88650 4 0.282494 34 0.282480 -0.1 1.2 1.15 479 7 90 6
GCH-31_217 0.0362 31 0
.00124 8 1.46712
1.88667 6 0.282458 27 0.282446 -1.4 1.0 1.21 474 6 100 6
GCH-31_216 0.0518 42 0
.00173 11 1.46712
1.88674 5 0.282512 44 0.282497 0.4 1.6 1.12 475 7 71 6
GCH-31_215 0.0826 66 0
.00279 17 1.46717
1.88662 7 0.282399 29 0.282373 -3.5 1.0 1.35 499 7 98 6
GCH-31_214 0.0480 40 0
.00165 10 1.46702
1.88662 6 0.282388 31 0.282373 -3.4 1.1 1.35 502 8 68 6
GCH-31_213 0.0996 93 0
.00335 26 1.46706
1.88655 5 0.282375 36 0.282345 -5.0 1.3 1.41 476 7 80 6
GCH-31_212 0.0306 26 0
.00108 7 1.46705
1.88651 5 0.282387 29 0.282377 -3.6 1.0 1.34 486 7 92 6
GCH-31_211 0.0554 51 0
.00189 14 1.46711
1.88677 6 0.282439 29 0.282421 -2.0 1.0 1.26 486 7 91 6
GCH-31_210 0
.0090 7 0.00030 2 1
.46709 1.88633 4 0.282433 47 0.282430 0.3 1.7 1.20 577 8 86 6
GCH-31_209 0.0148 12 0.00052 3 1.46712 1.88642 5 0.282440 32 0.282434 1.8 1.1 1.17 635 9 93 6
GCH-31_208 0.0490 42 0
.00164 11 1.46714
1.88666 6 0.282391 30 0.282375 -3.4 1.0 1.34 496 7 91 6
GCH-31_207 0.0679 54 0
.00230 14 1.46713 1
.88664 6 0.282474 25 0.282451 0.1 0.9 1.18 534 8 83 6
GCH-31_206 0.0187 17 0.00069 5 1.46713 1.88636 5 0.281682 32 0.281676 -28.4 1.1 2.69 487 7 90 6
GCH-31_205 0.0695 56 0
.00236 14 1.46712 1
.88671 6 0.282423 33 0.282400 -2.2 1.2 1.29 510 7 95 6
GCH-31_204 0.0503 45 0
.00172 12 1.46712
1.88660 6 0.282356 31 0.282340 -4.7 1.1 1.41 497 7 90 6
GCH-31_203 0.0638 55 0
.00215 14 1.46712 1
.88646 5 0.282416 39 0.282396 -2.8 1.4 1.30 493 9 79 6
GCH-31_202 0.0422 36 0
.00143 10 1.46703
1.88648 5 0.282418 34 0.282405 -2.5 1.2 1.29 492 7 86 6
GCH-31_201 0.0539 44 0
.00182 11 1.46717
1.88669 7 0.282439 24 0.282421 -1.3 0.8 1.25 519 8 95 6
GCH-31_200 0.0164 13 0.00068 4 1.46706 1.88642 4 0.281665 34 0.281638 7.9 1.2 2.06 2140 37 91 6
GCH-31_199 0.0830 67 0
.00276 17 1.46715
1.88678 8 0.282391 27 0.282366 -3.9 1.0 1.37 488 8 96 6
GCH-31_198 0.0506 66 0
.00171 20 1.46707
1.88676 5 0.282382 27 0.282366 -3.7 0.9 1.36 500 8 108 6
GCH-31_197 0.0316 30 0
.00108 8 1.46714
1.88680 5 0.282408 29 0.282398 -2.3 1.0 1.30 510 7 93 6
GCH-31_196 0.0414 42 0
.00141 12 1.46711
1.88659 5 0.282429 44 0.282416 -1.6 1.5 1.26 516 8 95 6
İ+I
(t)
d
Grain
ı
ı
±2ı
c
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.
333