295 / 352
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
İ+I
(t)
d
Grain
ı
ı
±2ı
c
A108_seq4_26 0.0143 12 0.00060 4 1.46709 1.88633 7 0.281632 33 0.281609 4.2 1.2 2.18 2024 20 93 4
A112_seq4_26 0.0096 26 0.00034 9 1.46713 1.88647 8 0.280938 29 0.280922 -11.8 1.0 3.35 2388 12 92 4
A116_seq4_26 0.0710 118 0
.00244 37 1.46716 1
.88656 6 0.281643 34 0.281545 4.0 1.2 2.26 2115 15 94 4
A118_seq4_40 0.0299 24 0
.00112 7 1.46719
1.88665 9 0.281608 28 0.281567 1.1 1.0 2.29 1953 44 91 4
A123_seq4_40 0.0200 17 0.00066 4 1.46725 1.88658 12 0.280744 53 0.280706 -4.8 1.9 3.48 3012 14 90 4
A125_seq4_40 0.0198 42 0.
00058 12 1.46715 1.
88663 7 0.281602 41 0.281580 2.6 1.5 2.24 2000 22 90 4
A138_seq4_26 0.0107 9 0.00036 2 1.46707 1.88647 5 0.281279 36 0.281265 -8.2 1.3 2.85 2017 20 99 4
A145_seq4_26 0.0008 1 0.00002 0 1.46722 1.88656 5 0.281008 41 0.281007 -15.0 1.4 3.31 2118 17 93 4
A155_seq4_26 0.0162 20 0.00051 5 1.46719 1.88670 6 0.281257 29 0.281238 -10.4 1.0 2.93 1962 21 99 4
A161_seq4_26 0.0349 83 0
.00119 27 1.46711
1.88621 7 0.282213 40 0.282203 -10.1 1.4 1.69 473 5 134
4
A162_seq4_26 0
.0020 3 0.00005 1 1
.46714 1.88625 8 0.281081 31 0.281078 -8.1 1.1 3.08 2308 14 93 4
A163_seq4_26 0.0208 20 0.
00072 6 1.46705 1.
88635 6 0.281307 35 0.281279 -8.1 1.2 2.83 1999 14 102 4
A164_seq4_26 0.0210 17 0.
00076 5 1.46709 1.
88639 7 0.282178 30 0.282169 -7.1 1.1 1.68 658 4 99 4
A168_seq4_26 0.0252 21 0.00084 5 1.46713 1.88619 6 0.281044 38 0.281005 -6.4 1.4 3.14 2494 15 101 4
A175_seq4_26 0
.0074 6 0.00024 1
1.46710 1.88645 7 0.281048 25 0.281037 -6.1 0.9 3.10 2457 14 95 4
A177_seq4_26 0.0166 13 0.00058 4 1.46719 1.88628 7 0.281127 31 0.281099 -1.0 1.1 2.92 2579 13 90 4
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.
279