serie NOVA TERRA nº 48

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176Yb a 176Lu a 178Hf 180Hf Sig Hf
b 176Hf 176Hf d “ ı c TDM
e agef
177Hf 177Hf 177Hf 177Hf (V) 177Hf 177Hf (t) İ+I (Ga) (Ma) İ+I(t)
d
Grain “ ı “ ı ±2ıc
Plesovice_40-5-90_3 0.0060 5 0.00015 1 1.46725 1.88682 14 0.282463 28 0.282462 -3.9 1.0 1.24 338
Plesovice_40-5-90_4 0.0035 3 0.00008 0 1.46713 1.88687 14 0.282466 24 0.282465 -3.8 0.9 1.23 338
Plesovice_40-5-90_5 0.0025 2 0.00006 0 1.46723 1.88694 14 0.282480 25 0.282480 -3.3 0.9 1.20 338
Plesovice_40-5-90_6 0.0057 5 0.00013 1 1.46727 1.88698 13 0.282515 29 0.282514 -2.1 1.0 1.14 338
Plesovice_40-5-90_7 0.0038 3 0.00009 1 1.46717 1.88670 13 0.282442 22 0.282441 -4.6 0.8 1.28 338
06-Nov
Plesovice_40-5-90_1 0.0055 4 0.00012 1 1.46719 1.88672 13 0.282471 23 0.282470 -3.6 0.8 1.22 338
Plesovice_40-5-90_2 0.0035 3 0.00008 0 1.46718 1.88697 11 0.282463 34 0.282462 -3.9 1.2 1.24 338
Plesovice_40-5-90_3 0.0079 6 0.00017 11.46718 1.88674 14 0.282446 20 0.282445 -4.5 0.7 1.27 338
Plesovice_40-5-90_4 0.0126 10 0.00029 2 1.46719 1.88684 12 0.282460 27 0.282458 -4.1 0.9 1.25 338
Plesovice_40-5-90_5 0.0056 5 0.00013 1 1.46724 1.88698 13 0.282482 32 0.282481 -3.2 1.1 1.20 338
Plesovice_40-5-90_6 0.0047 4 0.00011 1 1.46721 1.88689 13 0.282477 28 0.282477 -3.4 1.0 1.21 338
Plesovice_40-5-90_7 0.0025 2 0.00006 0 1.46716 1.88683 15 0.282448 46 0.282448 -4.4 1.6 1.27 338
Plesovice_40-5-90_7bis 0.0063 5 0.00014 1 1.46724 1.88692 13 0.282481 23 0.282480 -3.3 0.8 1.20 338
Plesovice_40-5-90_8 0.0052 4 0.00012 1 1.46721 1.88677 13 0.282478 22 0.282478 -3.4 0.8 1.21 338
Plesovice_40-5-90_9 0.0049 4 0.00011 1 1.46721 1.88679 13 0.282490 27 0.282489 -2.9 1.0 1.19 338
Plesovice_40-5-90_10 0.0031 3 0.00007 0 1.46716 1.88673 14 0.282472 24 0.282472 -3.5 0.8 1.22 338
Plesovice_40-5-90_11 0.0079 6 0.00018 11.46721 1.88693 13 0.282497 26 0.282496 -2.7 0.9 1.17 338
07-Nov
Plesovice-100-100-5_1 0.0034 3 0.00008 0 1.46717 1.88671 15 0.282465 22 0.282465 -3.8 0.8 1.23 338
Plesovice-100-90-5_2 0.0049 4 0.00012 1 1.46719 1.88685 14 0.282469 17 0.282468 -3.7 0.6 1.23 338
Plesovice-100-90-5_3 0.0036 3 0.00008 1 1.46716 1.88672 13 0.282468 22 0.282467 -3.7 0.8 1.23 338
Plesovice-100-90-5_4 0.0039 3 0.00009 1 1.46720 1.88670 15 0.282455 20 0.282454 -4.2 0.7 1.25 338
Plesovice-100-90-5_5 0.0051 4 0.00012 1 1.46724 1.88685 13 0.282481 26 0.282480 -3.3 0.9 1.20 338
Plesovice-100-90-5_6 0.0055 4 0.00013 1 1.46717 1.88679 13 0.282459 23 0.282458 -4.0 0.8 1.25 338
Plesovice-100-90-5_7 0.0053 4 0.00013 1 1.46724 1.88680 13 0.282493 20 0.282493 -2.8 0.7 1.18 338
Plesovice-100-90-5_8 0.0059 5 0.00014 1 1.46717 1 .88676 14 0.282456 25 0.282455 -4.1 0.9 1.25 338
Mean 0.0054 37 0.00012 81.46719 1.88677 14 0.282466 31 0.282466 -3.8 1.1 1.23
41
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-1 and WůĞƐŽǀŝēĞ zircon. Accuracy and reproducibility was checked by repeated analyses of
reference zircon GJ-1 and WůĞƐŽǀŝēĞ (data given as mean with 2 standard deviation uncertainties).
(a) 176 Yb/177Hf = (176Yb/173Yb)true x (173 Yb/177Hf)meas x (M173(Yb)/M177(Hf)) ɴ;,ĨͿ, ɴ;,ĨͿ = ln((179 Hf/177Hftrue)/(179 Hf/177 Hfmeasured)) / ln(M179(Hf)/M177(Hf)), M
= mass of respective isotopes. The 176 Lu/177Hf was calculated in a similar way using 175 Lu/177Hf and ɴ;zďͿ.
(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 Hf and ɸ,Ĩ calculated using the apparent U-Pb age determined by LA-ICP-MS dating (see column f), and the CHUR
parameters: 176Lu/177Hf = 0.0336, and 176Hf/177Hf = 0.282785 (Bouvier et al. 2008).
(e) Two stage model age in Ga using measured 176Lu/177Lu 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 176Lu/177Lu = 0.0379, and 176Hf/177Hf =
0.283164.
(f) Apparent U-Pb age determined by LA-ICP-MS.
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