Overview of Results from the Greenstone ... - Geology Ontario

Table A2. Ion microprobe (SHRIMP II) U-Th-Pb data for Abitibi zircons.
204
U Th Pb* Pb f206
207 Pb/
206 Pb ± 1σ Disc. Corr.
206
Spot (ppm) (ppm) Th/U (ppm) (ppb) Pb/
204 Pb (%)
207 Pb/
235 U ± 1σ
206 Pb/
238 U ± 1σ
207 Pb/
206 Pb ± 1σ Age (Ma) (%) Coeff.
97JAA-106, Rhyolite, Deloro assemblage, Shining Tree area, Macmurchy Township (E487060, N5275406; see Ayer et al., 2002).
15.1 136 91 0.687 84 7 8115 0.21 13.4740 ± 0.3077 0.51160 ± 0.00991 0.19101 ± 0.00189 2750.9 ± 16.4 3.9 0.903
8.1 194 70 0.372 107 4 18965 0.09 13.0916 ± 0.2480 0.50011 ± 0.00799 0.18986 ± 0.00159 2740.9 ± 13.8 5.6 0.899
2.1 141 49 0.362 78 1 46468 0.04 13.1258 ± 0.2585 0.50186 ± 0.00818 0.18969 ± 0.00174 2739.5 ± 15.2 5.2 0.886
19.1 213 129 0.627 127 9 10580 0.16 13.2750 ± 0.2704 0.50900 ± 0.00916 0.18915 ± 0.00143 2734.8 ± 12.5 3.7 0.930
11.1 172 61 0.365 97 1 102249 0.02 13.2249 ± 0.2235 0.50736 ± 0.00736 0.18905 ± 0.00133 2733.9 ± 11.6 3.9 0.911
14.1 293 119 0.421 171 1 179533 0.01 13.4682 ± 0.2086 0.51924 ± 0.00731 0.18812 ± 0.00093 2725.8 ± 8.1 1.3 0.949
3.1 279 127 0.471 158 6 18464 0.09 12.9750 ± 0.2232 0.50115 ± 0.00743 0.18778 ± 0.00133 2722.8 ± 11.7 4.6 0.913
16.1 370 193 0.540 213 3 48403 0.04 12.9360 ± 0.2325 0.49994 ± 0.00813 0.18766 ± 0.00110 2721.8 ± 9.7 4.8 0.946
6.1 149 52 0.364 84 1 86356 0.02 13.0874 ± 0.2413 0.50740 ± 0.00796 0.18707 ± 0.00148 2716.6 ± 13.1 3.2 0.904
1.1 412 193 0.484 232 5 32520 0.05 12.8121 ± 0.2239 0.49698 ± 0.00741 0.18697 ± 0.00139 2715.7 ± 12.3 5.1 0.907
12.1 184 81 0.455 108 3 24004 0.07 13.4759 ± 0.2356 0.52409 ± 0.00769 0.18649 ± 0.00147 2711.4 ± 13.0 -0.2 0.895
7.1 116 36 0.317 66 1 100000 0.02 13.1974 ± 0.2266 0.51531 ± 0.00756 0.18575 ± 0.00135 2704.9 ± 12.0 1.2 0.908
18.1 135 62 0.478 79 11 5424 0.32 13.3194 ± 0.2882 0.52084 ± 0.00960 0.18547 ± 0.00172 2702.4 ± 15.4 0.0 0.906
9.1 530 344 0.670 302 8 26226 0.07 12.2713 ± 0.1776 0.48209 ± 0.00647 0.18461 ± 0.00074 2694.7 ± 6.6 7.1 0.962
13.1 211 164 0.802 133 1 100000 0.02 13.2321 ± 0.2165 0.52141 ± 0.00752 0.18406 ± 0.00113 2689.8 ± 10.2 -0.7 0.928
20.1 343 191 0.574 179 3 42017 0.04 11.4825 ± 0.2468 0.45337 ± 0.00889 0.18369 ± 0.00123 2686.5 ± 11.1 12.3 0.951
4.1 347 143 0.424 196 9 16567 0.11 12.6757 ± 0.2039 0.50450 ± 0.00733 0.18222 ± 0.00097 2673.2 ± 8.9 1.8 0.944
96TB-0079, Dacite footwall to Langmuir #2 Ni mine, Lower Tisdale assemblage, Langmuir Township (see Barrie and Corfu, 1999), # 25 on Fig. 2.
4.1 119 56 0.484 69 1 39573 0.04 13.3650 0.2908 0.50249 0.00740 0.19290 0.00276 2767.1 23.6 6.3 0.759
2.2 88 83 0.974 55 3 11053 0.16 13.1610 0.2692 0.49639 0.00826 0.19229 0.00192 2761.8 16.5 7.2 0.874
19.1 289 152 0.544 160 46 2612 0.66 12.7760 0.2102 0.48506 0.00695 0.19103 0.00124 2751.0 10.7 8.9 0.920
15.1 137 95 0.714 87 0 952381 0.00 13.9360 0.2866 0.52919 0.00726 0.19099 0.00262 2750.7 22.7 0.6 0.750
4.3 74 33 0.462 41 0 100000 0.02 12.9510 0.2927 0.49270 0.00957 0.19064 0.00179 2747.7 15.5 7.3 0.911
17.2 247 22 0.094 131 28 3785 0.46 13.2930 0.2527 0.50694 0.00872 0.19018 0.00118 2743.7 10.3 4.4 0.946
13.3 156 100 0.662 90 25 2559 0.68 12.6690 0.3153 0.48359 0.01033 0.19000 0.00197 2742.2 17.2 8.8 0.911
5.1 169 65 0.397 96 7 9909 0.18 13.3450 0.2538 0.50958 0.00667 0.18994 0.00233 2741.6 20.3 3.9 0.769
18.1 370 18 0.049 194 16 10223 0.17 13.2200 0.2453 0.50589 0.00875 0.18952 0.00092 2738.0 8.0 4.4 0.966
17.1 387 19 0.052 205 42 4055 0.43 13.3660 0.2458 0.51169 0.00602 0.18945 0.00241 2737.4 21.1 3.3 0.727
9.1.2 542 47 0.089 279 27 8553 0.20 12.8650 0.2652 0.49364 0.00977 0.18902 0.00072 2733.6 6.3 6.5 0.983
3.1 138 47 0.348 79 5 12625 0.14 13.3460 0.2946 0.51334 0.00721 0.18855 0.00290 2729.6 25.5 2.6 0.723
11.1 513 511 1.030 346 17 14090 0.12 13.7840 0.2015 0.53094 0.00616 0.18829 0.00142 2727.3 12.5 -0.8 0.858
9.1 670 55 0.085 373 10 31114 0.06 13.8360 0.2015 0.53351 0.00640 0.18810 0.00129 2725.6 11.4 -1.4 0.883
14.2 132 100 0.788 82 7 8506 0.20 13.2020 0.2472 0.50933 0.00818 0.18799 0.00147 2724.6 13.0 3.2 0.910
21.1 167 190 1.178 109 33 2198 0.79 13.1450 0.2859 0.50814 0.00929 0.18762 0.00182 2721.4 16.1 3.3 0.897
22.1 45 27 0.624 26 5 4097 0.42 12.5570 0.3204 0.48559 0.00932 0.18755 0.00273 2720.8 24.2 7.5 0.824
8.1 670 63 0.098 364 26 11692 0.15 13.4520 0.1826 0.52076 0.00571 0.18735 0.00127 2719.1 11.2 0.8 0.870
6.1 233 126 0.559 133 9 10442 0.17 12.7310 0.2316 0.49600 0.00611 0.18615 0.00222 2708.5 19.9 5.0 0.759
15.2 557 70 0.130 294 4 60533 0.03 12.8570 0.1984 0.50244 0.00599 0.18560 0.00156 2703.5 14.0 3.6 0.840
8.2 935 34 0.038 462 54 7186 0.24 12.1260 0.1820 0.48237 0.00661 0.18232 0.00085 2674.1 7.7 6.2 0.951
Uncertainties are reported at 1σ (absolute) and are calculated by numerical propagation of all known sources of error.
Pb* = radiogenic Pb; f206 (%): Percentage of 206Pb which is common.
Disc (%) = Percent discordance along a chord to origin for the given 207Pb/206Pb age; Corr. Coeff. = Correlation coefficient (rho).
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