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207
Pb
a
U
b
Pb
b
Th
b 206
Pbc
c 207
Pb
d
±2s
206
Pb
d
±2s ȡ
e
207
Pb
d
±2s
206
Pb
f
±2s
207
Pb
f
±2s
207
Pb
f
±2s Conc.
g
(cps) (ppm) (ppm)
U (%)
235
U (%)
238
U (%) (rho)
206
Pb (%)
238
U (Ma)
235
U (Ma)
206
Pb (Ma) (%)
Grain
A409 85501 123 88 0.65 0.1 16.58 1.8 0.5700 1.6 0.90 0.2109 0.8 2908 38 2911 17 2912 13 100
A014 40795 183 136 0.72 0.1 17.35 1.7 0.5752 1.5 0.91 0.2188 0.7 2929 36 2955 16 2972 11 99
A429 51779 64 47 0.43 0.2 18.88 1.6 0.6026 1.5 0.92 0.2273 0.6 3040 37 3036 16 3033 10 100
A402
120 3
0 0.53 0.2 0.9426 16.8 0.08735 5.2 0.31 0.07826 15.9 540 27 674 86 1154 316 47
A438 22949 92 29 0.17 0.3 5.076 1.8 0.3057 1.4 0.78 0.1204 1.1 1719 21 1832 15 1963 20 88
A042 110366 1215 374 0 0.2 5.348 1.7 0.3134 1.5 0.9 0.1237 0.7 1758 24 1877 14 2011 12 87
91500
h
8378 74 13 0.29 0.5 1.850 1.8 0.1795 1.4 0.54 0.07477 0.9 1064 14 1063 12 1062 18 100
Felix
h
12482 435 68 2.47 0.2 0.6484 3.0 0.08211 3.0 0.43 0.05728 3.0 509 15 507 12 502 65 102
Plesovice
h
2852 651 34 0.09 1.3 0.3989 4.1 0.05419 2.2 0.48 0.05339 2.9 340 7 341 12 345 64 99
206
Pb/
238
U error is the quadratic additions of the within run precision (2 SE) and the external reproducibility (2 SD) of the reference zircon.
207
Pb/
206
Pb error propagation
(
207
Pb signal dependent) following Gerdes & Zeh (2009).
207
Pb/
235
U error is the quadratic addition of the
207
Pb/
206
Pb and
206
Pb/
238
U uncertainty.
a
Within run background-correctedmean
207
Pb signal in cps (counts per second).
b
U and Pb content and Th/U ratio were calculated relative to GJ-1 reference zircon.
c
Percentage of the common Pb on the
206
Pb. b.d. = below detection limit.
d
Pb/U and Pb/Pb ratios. Corrected for background, within-run Pb/U fractionation (in case of
206
Pb/
238
U) and common Pb using Stacy and Kramers (1975) model Pb
composition and subsequently normalised to GJ-1 (ID-TIMS value/measured value);
207
Pb/
235
U calculated using ((
207
Pb/
206
Pb)*(
238
U/
206
Pb)*137.88).
e
ZŚŽ ;ʌͿ ŝƐ ƚŚĞ ;
206
Pb/
238
U)/(
207
Pb/
235
U) error correlation coefficient.
f
Pb/U and Pb/Pb ages.
g
Degree of concordance = ((
206
Pb/
238
U age)/(
207
Pb/
206
Pb age)) x 100.
233