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

Table A2. continued
Struct. U Th Pb* 207 Pb/
206 Pb ± 1σ 204
Pb f206
Disc. Corr.
Spot Dom. (ppm) (ppm) Th/U (ppm) (ppb) 207 Pb/
235 U ± 1σ
206 Pb/
238 U ± 1σ
207 Pb/
206 Pb ± 1σ Age (Ma) 206
Pb/
204 Pb (%)
(%) Coeff.
99JAA-0057, Heterolithic volcanic breccia, Timiskaming assemblage, Swayze Township (E038175, N5297199; see Ayer, Ketchum and Trowell 2002)
13.1 sharp, elong igneous frag 62 64 1.065 41 37 753 2.30 13.4560 ± 0.4039 0.50635 ± 0.00866 0.19274 ± 0.00436 2765.7 ± 37.6 5.5 0.664
6.1 core 78 54 0.721 48 4 8777 0.20 13.5290 ± 0.3494 0.51718 ± 0.01130 0.18973 ± 0.00215 2739.8 ± 18.7 2.3 0.901
9.1 sharp, elong igneous frag 123 150 1.259 83 5 11342 0.15 13.1660 ± 0.2729 0.50643 ± 0.00898 0.18855 ± 0.00165 2729.6 ± 14.5 3.9 0.908
17.1 center; v. rounded grain 100 94 0.966 64 6 7820 0.22 13.0290 ± 0.2667 0.50696 ± 0.00880 0.18639 ± 0.00166 2710.6 ± 14.8 3.0 0.902
18.1 center; slightly rounded exterior 80 30 0.385 45 9 3785 0.46 12.8790 ± 0.2856 0.50277 ± 0.00842 0.18578 ± 0.00234 2705.2 ± 20.9 3.6 0.827
8.1 center; fairly rounded exterior 570 595 1.077 259 121 1582 1.10 9.9071 ± 0.2706 0.38687 ± 0.00760 0.18573 ± 0.00310 2704.7 ± 27.8 25.8 0.795
1.1 core 599 801 1.381 432 6 49603 0.04 13.6090 ± 0.1944 0.53182 ± 0.00718 0.18559 ± 0.00061 2703.5 ± 5.4 -2.1 0.974
11.1 sharp, elong igneous frag 151 166 1.132 98 6 10549 0.16 12.9580 ± 0.2484 0.50641 ± 0.00841 0.18558 ± 0.00143 2703.4 ± 12.8 2.8 0.917
16.1.2 center or core?; prism. grain exterior 96 70 0.753 56 5 7430 0.23 12.4050 ± 0.3098 0.48479 ± 0.00886 0.18559 ± 0.00276 2703.4 ± 24.8 6.9 0.806
12.1 elong., slightly rounded 52 54 1.081 32 10 2171 0.80 12.3340 ± 0.3274 0.48207 ± 0.00831 0.18556 ± 0.00337 2703.2 ± 30.3 7.5 0.735
15.1 center; fairly rounded exterior 209 319 1.575 150 11 8527 0.20 13.0330 ± 0.2335 0.51073 ± 0.00784 0.18508 ± 0.00139 2698.9 ± 12.5 1.8 0.909
5.1 core? of rounded gr 799 417 0.539 479 28 12887 0.13 13.3800 ± 0.2043 0.52508 ± 0.00759 0.18481 ± 0.00064 2696.6 ± 5.7 -1.1 0.975
4.1 center or core? 108 62 0.599 64 8 6077 0.29 13.1460 ± 0.2543 0.51594 ± 0.00788 0.18479 ± 0.00187 2696.4 ± 16.8 0.7 0.855
10.1 center; slightly rounded exterior 312 492 1.629 224 4 31918 0.05 12.8420 ± 0.2216 0.50812 ± 0.00793 0.18330 ± 0.00103 2683.0 ± 9.4 1.6 0.946
14.1 embayment on long prism 272 42 0.159 136 18 6128 0.28 11.9600 ± 0.2151 0.47630 ± 0.00778 0.18211 ± 0.00105 2672.2 ± 9.6 7.3 0.948
2.1 angular, core? In rounded elong grain 407 110 0.280 219 104 1695 1.02 12.4140 ± 0.2016 0.50195 ± 0.00693 0.17936 ± 0.00125 2647.0 ± 11.7 1.1 0.904
03JAA-0006, Syenitic feldspar porphyry, Discovery outcrop, Kirkland Lake, Teck Township (E571986, N5333892), #30 on Fig. 2.
10.1 core 75 30 0.410 43 5 6273 0.28 13.0790 ± 0.2901 0.50333 ± 0.00822 0.18846 ± 0.00247 2728.8 ± 21.8 4.5 0.810
12.1 core 178 92 0.532 101 2 30931 0.06 12.7280 ± 0.2140 0.49148 ± 0.00709 0.18782 ± 0.00132 2723.2 ± 11.6 6.5 0.910
9.1 core 163 100 0.633 96 22 3148 0.55 12.9370 ± 0.2371 0.50255 ± 0.00737 0.18670 ± 0.00174 2713.3 ± 15.4 4.0 0.864
4.1 core 175 84 0.494 101 1 134771 0.01 12.9420 ± 0.2522 0.50412 ± 0.00793 0.18620 ± 0.00181 2708.9 ± 16.1 3.5 0.870
2.1 core 347 208 0.619 199 6 24704 0.07 12.4840 ± 0.2555 0.48747 ± 0.00786 0.18574 ± 0.00199 2704.8 ± 17.8 6.5 0.854
13.1 core 97 33 0.350 55 5 8063 0.22 13.2120 ± 0.2725 0.51623 ± 0.00880 0.18562 ± 0.00180 2703.7 ± 16.1 0.9 0.885
5.1 core? 157 67 0.441 88 2 26889 0.06 12.6760 ± 0.2226 0.49559 ± 0.00743 0.18551 ± 0.00139 2702.8 ± 12.4 4.9 0.906
17.1 core? 273 188 0.710 160 10 11639 0.15 12.5840 ± 0.2298 0.49243 ± 0.00779 0.18534 ± 0.00137 2701.3 ± 12.2 5.4 0.917
11.1 core 619 485 0.809 371 24 10810 0.16 12.6740 ± 0.2117 0.49609 ± 0.00785 0.18529 ± 0.00070 2700.8 ± 6.2 4.7 0.975
6.1 core 345 126 0.376 196 3 44984 0.04 13.0320 ± 0.3851 0.51240 ± 0.01055 0.18446 ± 0.00346 2693.4 ± 31.4 1.2 0.776
1.1 core 256 92 0.372 143 15 7465 0.23 12.8220 ± 0.2049 0.50490 ± 0.00705 0.18418 ± 0.00114 2690.9 ± 10.3 2.5 0.923
18.2 rim 1027 471 0.474 591 7 63052 0.03 12.8960 ± 0.1934 0.50977 ± 0.00704 0.18347 ± 0.00080 2684.5 ± 7.2 1.3 0.958
19.1 core 672 198 0.305 362 16 17928 0.10 12.4210 ± 0.1825 0.49430 ± 0.00681 0.18225 ± 0.00067 2673.5 ± 6.1 3.8 0.969
3.1 magmatic? 492 459 0.965 301 73 2865 0.61 12.1440 ± 0.1859 0.49035 ± 0.00664 0.17962 ± 0.00102 2649.4 ± 9.4 3.5 0.931
14.1 rim 234 55 0.243 129 14 7567 0.23 12.7160 ± 0.2316 0.51568 ± 0.00833 0.17884 ± 0.00119 2642.1 ± 11.1 -1.8 0.932
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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