A1

Appendix

Table A-1

SHRIMP U-Pb zircon data for zircons from sample K12, Leeuwdraai Formation, Koras Group (Central Domain)

Spot % ppm ppm 232Th/ ppm (1) (1) % (1) (1) (1)

206Pbc U Th 238U 206Pb* 206Pb/ 207Pb/ Discord- 207Pb*/ ± % 207Pb*/ ± % 206Pb*/ ± % error

238U age 206Pb age ant 206Pb* 235U 238U correlation

1.2 -- 85 77 0.93 13.7 1105 ± 14 1109 ± 18 0 0.07655 0.91 1.973 1.6 0.187 1.4 0.830

1.3 0.00 154 141 0.95 24.5 1096 ± 11 1104 ± 11 1 0.07635 0.54 1.95 1.2 0.1853 1.1 0.897

2.2 0.03 93 104 1.16 14.5 1076 ± 19 1084 ± 14 1 0.07557 0.71 1.892 2.1 0.1816 1.9 0.938

3.2 0.03 104 100 0.99 16.9 1112 ± 12 1093 ± 17 -2 0.07593 0.82 1.972 1.4 0.1883 1.2 0.813

3.3 0.11 84 79 0.97 13.8 1133 ± 12 1101 ± 21 -3 0.07622 1 2.019 1.6 0.1921 1.2 0.753

4.1 0.15 166 131 081 27.4 1127 ± 12 1090 ± 19 -3 0.0758 0.95 1.996 1.5 0.191 1.1 0.764

4.2 0.06 94 94 1.03 15.1 1104 ± 13 1094 ± 16 -1 0.07594 0.82 1.955 1.5 0.1867 1.3 0.848

5.1 0.18 97 79 0.84 15.3 1084 ± 12 1099 ± 24 1 0.07615 1.2 1.922 1.7 0.1831 1.2 0.717

6.1 0.04 142 154 1.12 23.2 1122 ± 12 1100 ± 16 -2 0.07617 0.79 1.998 1.4 0.1902 1.2 0.823

7.1 0.19 127 128 1.04 20.3 1099 ± 12 1102 ± 26 0 0.07626 1.3 1.955 1.8 0.1859 1.2 0.666

7.2 0.19 66 66 1.03 10.6 1108 ± 12 1103 ± 25 0 0.07629 1.2 1.972 1.7 0.1875 1.2 0.703

8.1 0.33 119 91 0.80 18.9 1094 ± 12 1104 ± 27 1 0.0763 1.3 1.946 1.8 0.1849 1.2 0.664

8.2 0.06 178 157 0.91 28.1 1086 ± 11 1101 ± 13 1 0.07624 0.63 1.928 1.2 0.1834 1.1 0.863

9.1 0.28 123 116 0.98 19.6 1092 ± 12 1104 ± 24 1 0.07634 1.2 1.943 1.7 0.1846 1.2 0.706

9.2 0.00 61 63 1.07 9.7 1094 ± 16 1105 ± 22 1 0.07637 1.1 1.947 2 0.1849 1.6 0.825

10.1 0.15 119 126 1.10 19.1 1104 ± 12 1109 ± 30 0 0.0765 1.5 1.971 1.9 0.1868 1.2 0.617

10.2 0.06 117 92 0.81 18.5 1084 ± 11 1102 ± 16 2 0.07625 0.78 1.926 1.4 0.1832 1.1 0.818

11.1 0.21 133 138 1.07 21.3 1097 ±12 1111 ± 21 1 0.07659 1.1 1.958 1.6 0.1854 1.2 0.736

12.1 0.18 117 133 1.18 18.9 1110 ± 12 1084 ± 27 -2 0.0756 1.3 1.958 1.8 0.1879 1.2 0.661

12.2 0.09 50 54 1.12 7.97 1104 ± 13 1088 ± 21 -1 0.07573 1 1.951 1.6 0.1868 1.2 0.767

13.1 0.21 140 119 0.87 22.3 1093 ± 13 1105 ± 21 1 0.07639 1 1.946 1.7 0.1847 1.3 0.783

13.2 0.05 104 88 0.87 16.5 1088 ± 13 1099 ± 14 1 0.07616 0.71 1.931 1.4 0.1839 1.3 0.871

14.1 0.24 119 116 1.01 19.4 1121 ± 12 1090 ± 26 -3 0.07582 1.3 1.985 1.7 0.1898 1.2 0.676

15.1 0.18 143 122 0.88 23.1 1109 ± 12 1104 ± 20 0 0.07633 0.98 1.975 1.5 0.1876 1.2 0.761

16.1 0.14 138 144 1.08 22.2 1101 ± 12 1105 ± 23 0 0.07637 1.1 1.961 1.6 0.1862 1.2 0.713

17.1 0.18 132 135 1.05 21.5 1119 ±12 1099 ± 23 -2 0.07616 1.1 1.99 1.6 0.1895 1.2 0.715

18.1 0.34 85 71 0.87 13.8 1114 ± 13 1093 ± 36 -2 0.0759 1.8 1.975 2.2 0.1887 1.2 0.572

19.1 0.37 84 71 0.87 13.4 1095 ± 12 1081 ± 45 -1 0.0755 2.2 1.926 2.6 0.1851 1.2 0.482

20.1 0.29 109 93 0.88 17.5 1104 ± 12 1087 ± 25 -2 0.07568 1.3 1.949 1.7 0.1868 1.2 0.685

21.1 -- 130 112 0.89 20.9 1102 ± 11 1111 ± 15 1 0.07661 0.74 1.969 1.3 0.1864 1.1 0.835

22.1 0.06 164 153 0.96 25.9 1086 ± 11 1093 ± 19 1 0.07594 0.94 1.922 1.4 0.1835 1.1 0.760

23.1 0.09 83 86 1.07 13.2 1092 ±12 1086 ± 19 -1 0.07565 0.93 1.925 1.5 01846 1.1 0.778

24.1 0.10 92 85 0.96 14.7 1102 ± 12 1083 ± 20 -2 0.07553 10 1.941 1.5 0.1864 1.1 0.753

Table A-2

SHRIMP U-Pb zircon data for zircons from sample K33, Welgevind Formation, Koras Group (Northern Domain)

Spot % ppm ppm 232Th/ ppm (1) (1) % (1) (1) (1)

206Pbc U Th 238U 206Pb* 206Pb/ 207Pb/ Discord- 207Pb*/ ± % 207Pb*/ ± % 206Pb*/ ± % error

238U age 206Pb age ant 206Pb* 235U 238U correlation

1.3 0.05 123 131 1.10 19.5 1095 ± 11 1097 ± 17 0 0.07606 0.86 1.941 1.4 0.1851 1.1 0.796

4.2 0.00 138 164 1.23 20.9 1049 ± 11 1091 ± 13 4 0.07586 0.63 1.849 1.3 0.1768 1.1 0.866

5.1 0.07 268 366 1.41 42.6 1095 ± 11 1095 ± 11 0 0.07598 0.57 1.939 1.2 0.1851 1.1 0.881

6.1 0.00 63 47 0.77 10.2 1104 ± 13 1107 ± 20 0 0.07645 1 1.97 1.6 0.1869 1.2 0.775

7.1 0.06 61 59 1.00 9.53 1075 ± 12 1106 ± 21 3 0.0764 1 1.912 1.6 0.1815 1.2 0.760

8.1 0.00 100 106 1.09 15.5 1070 ± 11 1115 ± 17 4 0.07676 0.87 1.911 1.4 0.1805 1.1 0.798

9.1 0.00 66 61 0.96 10.4 1084 ± 14 1110 ± 20 2 0.07657 0.98 1.934 1.7 0.1832 1.4 0.816

10.1 0.00 72 64 0.92 11.4 1099 ± 12 1111 ±19 1 0.0766 0.95 1.964 1.5 0.1859 1.2 0.787

11.1 0.20 29 26 0.94 4.65 1115 ± 15 1093 ± 36 -2 0.0759 1.8 1.977 2.3 0.1889 1.5 0.631

12.1 0.03 113 110 1.01 17.9 1095 ± 11 1094 ± 16 0 0.07596 0.79 1.939 1.4 0.1852 1.1 0.823

13.1 0.11 104 91 0.91 16.7 1101 ± 12 1113 ± 22 1 0.07669 1.1 1.97 1.6 0.1863 1.2 0.723

14.1 0.09 86 85 1.02 13.7 1099 ± 12 1104 ± 21 0 0.07636 1.1 1.957 1.6 0.1859 1.2 0.741

15.1 0.00 103 106 1.06 16.5 1103 ± 12 1096 ± 16 -1 0.07602 0.78 1.956 1.4 0.1867 1.1 0.827

16.1 0.00 76 71 0.97 12.2 1105 ± 14 1093 ± 18 -1 0.07591 0.89 1.958 1.6 0.1871 1.4 0.837

18.1 0.13 93 120 1.33 14.9 1097 ± 12 1077 ± 20 -2 0.07531 0.99 1.927 1.5 0.1855 1.2 0.768

19.1 0.00 72 74 1.07 11.5 1104 ± 17 1098 ± 19 -1 0.07612 0.94 1.961 1.9 0.1868 1.7 0.869

20.1 0.00 70 67 0.99 11.3 1105 ± 12 1100 ± 19 0 0.07618 0.95 1.964 1.5 0.187 1.2 0.786

21.1 0.12 85 70 0.85 13.2 1077 ± 12 1115 ± 21 3 0.07677 1 1.925 1.6 0.1819 1.2 0.747

22.1 0.00 80 69 0.90 12.8 1109 ± 17 1112 ± 17 0 0.07665 0.86 1.985 1.9 0.1878 1.7 0.888

23.1 0.00 81 75 0.96 12.8 1083 ± 14 1102 ± 20 2 0.07625 10 1.923 1.7 0.1829 1.4 0.808

24.1 0.07 143 130 0.94 22.4 1079 ± 11 1101 ± 15 2 0.07624 0.75 1.915 1.3 0.1821 1.1 0.829

Errors are 1-sigma; Pbc and Pb* indicate the common and radiogenic portions respectively.

Error in standard calibration was 0.22% (not included in above errors but are required when comparing data from different mounts).

(1)Common Pb corrected using measured 204Pb

For all samples zircons were concentrated using conventional mineral separation techniques, then hand-picked, mounted in epoxy and polished, prior to analysis using the Sensitive High Resolution Microprobe (SHRIMP), housed at the Research School of Earth Sciences (RSES) at The Australian National University. Details of the methodology applied are given by Williams (1998). Cathodoluminescence (CL) and backscatter electron (BSE) images were collected at the RSES. The standard zircon, FC-1 from the Duluth Complex, U.S.A., with an age of ~1100-1080 Ma, was used during analysis. Errors in the data tables and figures are at the 68% confidence level (1s), with final weighted mean ages reported at the 95% confidence level. Decay constants used were 1.55125 × 10-10 (238U) and 9.8485 × 10-10 (235U). Statistical analysis and U-Pb Concordia diagrams were generated using Isoplot (Version 3.61) (Ludwig, 2003).

Table A-3

SHRIMP U-Pb zircon data for zircons from sample K36, Welgevind Formation, Koras Group (Northern Domain)

Spot % ppm ppm 232Th/ ppm (1) (1) % (1) (1) (1)

206Pbc U Th 238U 206Pb* 206Pb/ 207Pb/ Discord- 207Pb*/ ± % 207Pb*/ ± % 206Pb*/ ± % error

238U age 206Pb age ant 206Pb* 235U 238U correlation

1.1 0.27 39 72 1.89 6.29 1102 ± 14 1096 ± 43 -1 0.076 2.1 1.955 2.5 0.1865 1.4 0.534

1.2 0.13 55 127 2.36 8.85 1096 ± 15 1110 ± 24 1 0.07659 1.2 1.957 1.9 0.1853 1.5 0.779

2.1 0.15 59 81 1.43 9.37 1097 ± 13 1112 ± 25 1 0.07664 1.3 1.96 1.8 0.1855 1.3 0.704

3.1 1.83 98 213 2.24 15.7 1079 ± 13 1103 ± 63 2 0.0763 3.1 1.917 3.4 0.1822 1.3 0.392

4.1 0.00 54 85 1.63 8.71 1111 ± 13 1109 ± 22 0 0.07655 1.1 1.985 1.7 0.1881 1.3 0.758

5.1 0.14 38 49 1.33 6.19 1112 ± 14 1083 ± 33 -3 0.0755 1.6 1.961 2.1 0.1883 1.4 0.649

5.2 0.11 62 95 1.57 9.82 1087 ± 12 1098 ± 20 1 0.07613 10 1.927 1.6 0.1836 1.2 0.768

6.1 0.11 49 67 1.42 7.78 1094 ± 13 1102 ± 25 1 0.07626 1.3 1.944 1.8 0.1849 1.3 0.714

7.1 0.21 41 59 1.49 6.57 1095 ± 14 1084 ± 41 -1 0.0756 2.1 1.93 2.5 0.1852 1.4 0.551

8.1 0.07 57 71 1.29 9.16 1112 ± 13 1109 ± 35 0 0.0765 1.7 1.986 2.2 0.1882 1.3 0.588

9.1 0.14 58 85 1.52 9.27 1107 ± 13 1094 ± 27 -1 0.0759 1.3 1.961 1.8 0.1873 1.3 0.695

9.2 0.15 65 102 1.61 10.6 1113 ± 12 1096 ± 21 -2 0.07603 1.1 1.976 1.6 0.1885 1.2 0.758

10.1 0.00 64 97 1.56 10.4 1117 ± 13 1073 ± 21 -4 0.07517 1 1.96 1.6 0.1892 1.2 0.764

10.2 0.12 57 79 1.41 9.13 1092 ± 17 1112 ± 24 2 0.07663 1.2 1.951 2.1 0.1846 1.7 0.805

11.1 0.00 49 62 1.32 7.85 1106 ± 13 1088 ± 23 -2 0.07575 1.2 1.954 1.7 0.1871 1.3 0.745

12.1 0.00 47 58 1.25 7.67 1111 ± 13 1117 ± 24 1 0.07683 1.2 1.993 1.8 0.1881 1.3 0.740

13.1 0.11 53 61 1.19 8.57 1104 ± 13 1088 ± 27 -1 0.757 1.3 1.95 1.9 0.1867 1.3 0.691

13.2 0.19 55 77 1.43 8.78 1090 ± 12 1086 ± 35 0 0.757 1.8 1.922 2.1 0.1842 1.2 0.571

14.1 1.06 53 56 1.10 7.97 1032 ± 13 1115 ± 80 7 0.768 4 1.838 4.2 0.1736 1.3 0.316

15.1 0.00 50 73 1.50 7.92 1092 ± 13 1105 ± 23 1 0.07636 1.2 1.944 1.7 0.1846 1.3 0.745

16.1 0.00 77 99 1.33 12.3 1105 ± 12 1092 ± 19 -1 0.0759 0.93 1.957 1.5 0.187 1.2 0.792

17.1 0.44 64 97 1.57 10.2 1099 ± 13 1107 ± 34 1 0.0764 1.7 1.96 2.1 0.1859 1.2 0.586

18.1 0.00 40 69 1.77 6.59 1120 ± 14 1111 ± 26 -1 0.07661 1.3 2.003 1.9 0.1897 1.4 0.728

19.1 0.11 54 72 1.37 8.7 1104 ± 13 1099 ± 26 0 0.07616 1.3 1.962 1.8 0.1868 1.3 0.696

20.1 0.00 44 67 1.58 7.01 1101± 13 1095 ± 24 -1 0.07598 1.2 1.951 1.8 0.1862 1.3 0.741

21.1 0.14 69 93 1.39 11.2 1108 ± 12 1092 ± 23 -1 0.07588 1.1 1.963 1.7 0.1876 1.2 .0730

Errors are 1-sigma; Pbc and Pb* indicate the common and radiogenic portions respectively.

Error in standard calibration was 0.22% (not included in above errors but are required when comparing data from different mounts).

(1)Common Pb corrected using measured 204Pb

A1

Appendix

Figure captions

Fig. A1. 207Pb/206Pb concordia plot for sample K12 of the Leeuwdraai Formation, Koras Group (Central Domain).

Fig. A2. 207Pb/206Pb concordia plots for samples of the Welgevind Formation, Koras Group (Northern Domain). a. Sample K3. b. Sample K36