279 / 352
207
Pb
a
U
b
Pb
b
Th
b 206
Pbc
c 207
Pb
d
±2
V
206
Pb
d
±2
V
ȡ
e 207
Pb
d
±2
V
206
Pb
f
±2
V
207
Pb
f
±2
V
207
Pb
f
±2
V
Con
(cps) (ppm) (ppm)
U (%)
235
U (%)
238
U (%) (rho)
206
Pb (%)
238
U (Ma)
235
U (Ma)
206
Pb (Ma) (%
Grain
A232 82683 673 236 0.11 0.2 7.7530 2.8 0.3271 1.5 0.54 0.1719 2.4 1825 24 2203 26 2576 39 71
A245 25484 247 101 0.30 0.1 7.7970 1.8 0.3683 1.4 0.78 0.1535 1.1 2021 24 2208 16 2386 19 85
A224 22282 102 42 0.40 0.6 8.1360 1.8 0.3643 1.4 0.80 0.1620 1.1 2003 25 2246 16 2476 18 81
A183 31622 128 64 0.76 0.3 8.5660 1.9 0.3917 1.6 0.86 0.1586 0.9 2131 29 2293 17 2441 16 87
A249 25294 206 91 0.44 0.2 8.6540 1.9 0.3789 1.6 0.85 0.1657 1.0 2071 28 2302 17 2514 17 82
A322 20492 166 82 0.77 b.d.
8.9280 2.0 0.3817 1.7 0.85 0.1696 1.1 2084 31 2331 19 2554 18 82
A225 32915 121 51 0.26 0.2 9.0000 2.0 0.3834 1.8 0.88 0.1702 0.9 2092 32 2338 18 2560 16 82
A345 13226 114 51 0.55 0.1 9.0190 2.0 0.3767 1.6 0.80 0.1737 1.2 2061 28 2340 18 2593 19 79
A316 106084 905 435 0.60 0.1 9.0210 2.6 0.3949 2.3 0.90 0.1657 1.1 2146 42 2340 24 2514 19 85
A303 95033 611 256 0.29 0.0 9.4900 2.1 0.3612 1.5 0.72 0.1906 1.5 1988 26 2387 20 2747 24 72
A256 52924 366 172 0.32 0.3 9.6690 2.0 0.4117 1.6 0.81 0.1703 1.2 2223 30 2404 18 2561 19 87
A295 63538 228 111 0.40 0.1 9.7360 1.7 0.4214 1.5 0.85 0.1676 0.9 2267 28 2410 16 2534 15 89
A321 68533 510 228 0.19 0.0 9.8100 1.6 0.4134 1.4 0.89 0.1721 0.7 2230 27 2417 15 2578 12 87
A208 85654 658 298 0.29 0.1 9.8760 1.6 0.4041 1.5 0.92 0.1772 0.6 2188 27 2423 15 2627 11 83
A231 63014 466 220 0.44 0.1 9.8980 1.6 0.4011 1.5 0.92 0.1790 0.7 2174 28 2425 15 2643 11 82
A323 136865 1048 459 0.16 0.0 9.9100 1.7 0.4072 1.5 0.90 0.1765 0.7 2202 29 2426 16 2620 12 84
A228 26232 207 102 0.40 0.2 10.2300 2.2 0.4301 1.9 0.88 0.1724 1.0 2306 38 2455 21 2581 17 89
A265 57376 379 192 0.52 0.3 10.3400 1.7 0.4183 1.4 0.86 0.1794 0.9 2253 27 2466 16 2647 14 85
A213 63200 227 116 0.52 0.1 10.4100 1.7 0.4234 1.6 0.91 0.1782 0.7 2276 30 2472 16 2637 12 86
A199 24080 172 85 0.37 0.0 10.5800 1.8 0.4307 1.5 0.82 0.1782 1.0 2309 29 2487 17 2636 17 88
91500
h
7017 61 11 0.25 0.4 1.8607 5.0 0.1807 5.7 0.61 0.0747 2.9 1071 56 1067 33 1060 58 10
Felix
h
6593 361 52 2.09 0.4 0.6274 10.0 0.0808 7.9 0.43 0.0563 5.1 501 38 494 39 464 114 11
Plesovice
h
2330 904 49 0.09 0.2 0.4243 10.5 0.0572 9.9 0.51 0.0538 1.5 359 35 359 32 362 33 99
GJ-1
h
6697 306 28 0.03 0.2 0.8144 2.1 0.0983 1.3 0.49 0.0601 2.2 604 7 605 10
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-corrected mean
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.
h
Mean of 13 (91500), 13 (Felix), 13 (Plesovice), and 26 (GJ-1) analyses, respectively.
263