Table 1. 40Ar/39Ar Dating of biotites from Leg 165 tephra layers.
Core,
section,
interval (cm) |
Analysis
number |
40Ar/39Ar
|
38Ar/39Ar
|
37Ar/39Ar
|
36Ar/39Ar
|
39Ar
|
Atm
(%) |
40Ar*/39Ar
|
Age
(Ma) |
±
(m.y.)
|
wi
|
xi*wi
|
Mean
|
Error
|
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
165-998A- | ||||||||||||||
13H-3, 32-33 | 1 | 12.497 | 0.172 | 0.000 | 0.016 | 49.28 | 61.11 | 7.636 | 40.73 | 0.98 | 1.04 | 42.4 | ||
13H-3, 32-33 | 2 | 8.671 | 0.157 | 0.002 | 0.012 | 59.67 | 58.26 | 5.052 | 27.05 | 0.50 | 3.96 | 107.2 | ||
13H-3, 32-33 | 3 | 4.431 | 0.163 | 0.015 | 0.001 | 20.92 | 90.63 | 4.016 | 21.53 | 0.99 | 1.02 | 22.1 | ||
13H-3, 32-33 | 4 | 10.336 | 0.164 | 0.011 | 0.016 | 36.78 | 52.98 | 5.476 | 29.30 | 0.77 | 1.67 | 48.9 | ||
13H-3, 32-33 | 5 | 16.674 | 0.175 | 0.024 | 0.031 | 17.42 | 44.86 | 7.480 | 39.91 | 1.29 | 0.60 | 24.1 | ||
13H-3, 32-33 | 6 | 4.021 | 0.156 | 0.005 | 0.002 | 77.59 | 88.86 | 3.573 | 19.17 | 0.35 | 7.99 | 153.1 | ||
24.42 | 0.25 | |||||||||||||
13H-5, 123-124 | 1 | 1.753 | 0.096 | 0.006 | 0.000 | 18.30 | 92.26 | 1.617 | 8.70 | 1.02 | 0.95 | 8.3 | ||
13H-5, 123-124 | 2 | 1.401 | 0.101 | -0.018 | 0.001 | 6.47 | 72.61 | 1.017 | 5.48 | 2.89 | 0.12 | 0.7 | ||
13H-5, 123-124 | 3 | 1.721 | 0.097 | -0.019 | 0.001 | 7.57 | 90.48 | 1.557 | 8.38 | 2.46 | 0.17 | 1.4 | ||
13H-5, 123-124 | 4 | 1.317 | 0.100 | -0.007 | 0.001 | 8.26 | 88.59 | 1.166 | 6.28 | 2.25 | 0.20 | 1.2 | ||
13H-5, 123-124 | 5 | 1.314 | 0.090 | -0.011 | 0.001 | 5.65 | 83.29 | 1.095 | 5.90 | 3.29 | 0.09 | 0.5 | ||
7.93 | 0.81 | |||||||||||||
20X-1, 133-134 | 1 | 3.391 | 0.069 | 0.024 | 0.001 | 11.41 | 87.17 | 2.956 | 15.88 | 1.65 | 0.37 | 5.9 | ||
20X-1, 133-134 | 2 | 2.703 | 0.069 | 0.012 | 0.000 | 17.76 | 94.83 | 2.564 | 13.78 | 1.06 | 0.89 | 12.2 | ||
20X-1, 133-134 | 3 | 2.433 | 0.074 | 0.020 | 0.001 | 9.31 | 89.04 | 2.166 | 11.65 | 2.02 | 0.25 | 2.9 | ||
13.94 | 0.82 | |||||||||||||
21X-4, 79-80 | 1 | 3.005 | 0.095 | -0.001 | 0.001 | 9.97 | 91.71 | 2.756 | 14.81 | 1.88 | 0.28 | 4.2 | ||
21X-4, 79-80 | 2 | 2.974 | 0.104 | 0.003 | 0.001 | 12.72 | 93.44 | 2.778 | 14.93 | 1.50 | 0.44 | 6.6 | ||
21X-4, 79-80 | 3 | 2.869 | 0.099 | 0.009 | 0.001 | 8.71 | 90.07 | 2.584 | 13.88 | 2.13 | 0.22 | 3.0 | ||
21X-4, 79-80 | 4 | 2.874 | 0.100 | 0.002 | 0.000 | 59.43 | 98.55 | 2.832 | 15.21 | 0.46 | 4.77 | 72.6 | ||
21X-4, 79-80 | 5 | 3.308 | 0.103 | 0.001 | 0.001 | 15.99 | 95.31 | 3.153 | 16.93 | 1.25 | 0.64 | 10.9 | ||
21X-4, 79-80 | 6 | 3.137 | 0.104 | -0.020 | 0.001 | 8.61 | 90.80 | 2.848 | 15.30 | 2.19 | 0.21 | 3.2 | ||
15.30 | 0.39 | |||||||||||||
27X-1, 120-122 | 1 | 3.802 | 0.120 | -0.001 | 0.001 | 54.93 | 91.08 | 3.463 | 18.58 | 0.42 | 5.80 | 107.9 | ||
27X-1, 120-122 | 2 | 3.274 | 0.130 | -0.001 | 0.000 | 30.68 | 97.53 | 3.193 | 17.14 | 0.64 | 2.45 | 42.0 | ||
27X-1, 120-122 | 3 | 3.247 | 0.127 | 0.001 | 0.000 | 41.87 | 96.35 | 3.129 | 16.80 | 0.50 | 4.03 | 67.7 | ||
27X-1, 120-122 | 4 | 3.312 | 0.117 | -0.002 | 0.000 | 34.53 | 97.83 | 3.241 | 17.40 | 0.59 | 2.88 | 50.1 | ||
27X-1, 120-122 | 5 | 3.327 | 0.096 | -0.001 | 0.000 | 18.88 | 96.05 | 3.195 | 17.15 | 1.05 | 0.91 | 15.7 | ||
27X-1, 120-122 | 6 | 4.029 | 0.165 | 0.000 | 0.001 | 41.61 | 96.30 | 3.880 | 20.81 | 0.51 | 3.79 | 78.8 | ||
27X-1, 120-122 | 7 | 3.671 | 0.141 | -0.002 | 0.001 | 8.95 | 92.45 | 3.394 | 18.21 | 2.12 | 0.22 | 4.0 | ||
27X-1, 120-122 | 8 | 3.544 | 0.103 | -0.004 | 0.001 | 10.13 | 93.08 | 3.299 | 17.71 | 1.87 | 0.29 | 5.1 | ||
27X-1, 120-122 | 9 | 3.482 | 0.147 | 0.003 | 0.001 | 27.85 | 93.60 | 3.259 | 17.50 | 0.75 | 1.78 | 31.1 | ||
18.16 | 0.21 | |||||||||||||
29X-3, 68-69 | 1 | 5.191 | 0.159 | -0.002 | 0.003 | 30.09 | 84.11 | 4.366 | 23.40 | 0.78 | 1.64 | 38.4 | ||
29X-3, 68-69 | 2 | 4.689 | 0.160 | -0.005 | 0.001 | 14.33 | 96.31 | 4.516 | 24.20 | 1.37 | 0.53 | 12.9 | ||
29X-3, 68-69 | 3 | 4.129 | 0.160 | 0.000 | 0.000 | 50.96 | 98.82 | 4.080 | 21.87 | 0.52 | 3.65 | 79.8 | ||
29X-3, 68-69 | 4 | 6.160 | 0.167 | -0.004 | 0.005 | 39.09 | 73.72 | 4.541 | 24.33 | 0.72 | 1.94 | 47.2 | ||
22.97 | 0.36 | |||||||||||||
29X-3, 69-70 | 1 | 2.343 | 0.059 | 0.016 | 0.001 | 19.69 | 86.55 | 2.028 | 10.90 | 0.95 | 1.10 | 12.0 | ||
29X-3, 69-70 | 2 | 1.737 | 0.063 | 0.008 | 0.001 | 31.02 | 88.48 | 1.537 | 8.27 | 0.61 | 2.71 | 22.4 | ||
29X-3, 69-70 | 3 | 19.636 | 0.095 | 0.021 | 0.040 | 29.02 | 39.45 | 7.746 | 41.31 | 1.41 | 0.50 | 20.7 | ||
12.79 | 0.48 | |||||||||||||
52X-1, 128-129 | 5.555 | 0.116 | 0.000 | 0.0013 | 100.00 | 5.55 | 30.70 | 18.63 | 30.70 | 18.63 | ||||
165-998B- | ||||||||||||||
1R-7, 53-54 | 1 | 6.095 | 0.103 | 0.000 | 0.0083 | 100.00 | 6.09 | 33.66 | 4.43 | 0.05 | 1.7 | |||
1R-7, 53-54 | 2 | 6.141 | 0.215 | 0.003 | 0.0118 | 87.75 | 5.39 | 29.79 | 2.02 | 0.24 | 7.3 | |||
1R-7, 53-54 | 3 | 6.258 | 0.233 | 0.000 | 0.0019 | 100.00 | 6.26 | 34.55 | 12.59 | 0.01 | 0.2 | |||
1R-7, 53-54 | 4 | 6.571 | 0.076 | 0.000 | 0.0067 | 100.00 | 6.57 | 36.27 | 3.62 | 0.08 | 2.8 | |||
1R-7, 53-54 | 5 | 5.931 | 0.080 | 0.001 | 0.0081 | 93.83 | 5.57 | 30.76 | 2.97 | 0.11 | 3.5 | |||
1R-7, 53-54 | 6 | 8.236 | 0.198 | 0.008 | 0.0076 | 71.62 | 5.90 | 32.59 | 3.19 | 0.10 | 3.2 | |||
31.67 | 1.30 | |||||||||||||
165-999A- | ||||||||||||||
27X-2, 150 | 1 | 0.873 | 0.0135 | 0.0001 | 0.000323967 | 156.999 | 89.03 | 0.7770 | 8.32 | 0.38 | 6.90 | 57.4 | ||
27X-2, 150 | 2 | 0.862 | 0.0131 | 0.0037 | 0.000219742 | 135.332 | 92.46 | 0.7968 | 8.53 | 0.44 | 5.13 | 43.8 | ||
27X-2, 150 | 3 | 0.908 | 0.0135 | 0.0106 | 0.000140563 | 149.829 | 95.42 | 0.8663 | 9.28 | 0.40 | 6.27 | 58.2 | ||
27X-2, 150 | 4 | 0.913 | 0.0146 | 0.0229 | 0.000477364 | 113.962 | 84.55 | 0.7721 | 8.27 | 0.52 | 3.65 | 30.2 | ||
27X-2, 150 | 5 | 0.890 | 0.0138 | 0.0153 | 0.000720032 | 35.454 | 76.09 | 0.6770 | 7.25 | 1.68 | 0.36 | 2.6 | ||
27X-2, 150 | 6 | 0.841 | 0.0146 | 0.0095 | 0.0000 | 37.418 | 100.00 | 0.8411 | 9.01 | 1.59 | 0.40 | 3.6 | ||
27X-2, 150 | 7 | 0.870 | 0.0142 | 0.0028 | 0.000772052 | 33.214 | 73.79 | 0.6423 | 6.88 | 1.79 | 0.31 | 2.1 | ||
27X-2, 150 | 8 | 0.858 | 0.0129 | 0.0004 | 0.000654051 | 45.658 | 77.47 | 0.6645 | 7.12 | 1.30 | 0.59 | 4.2 | ||
27X-2, 150 | 9 | 0.906 | 0.0130 | 0.0201 | 0.000502838 | 100.138 | 83.59 | 0.7571 | 8.11 | 0.59 | 2.83 | 22.9 | ||
27X-2, 150 | 10 | 0.954 | 0.0149 | 0.0154 | 0.000657564 | 76.896 | 79.64 | 0.7599 | 8.14 | 0.77 | 1.67 | 13.6 | ||
27X-2, 150 | 11 | 0.918 | 0.0130 | 0.0121 | 0.0000 | 84.521 | 100.00 | 0.9176 | 9.82 | 0.69 | 2.11 | 20.7 | ||
27X-2, 150 | 12 | 0.892 | 0.0151 | 0.0302 | 0.000108367 | 30.152 | 96.41 | 0.8603 | 9.21 | 1.93 | 0.27 | 2.5 | ||
27X-2, 150 | 13 | 0.925 | 0.0139 | 0.0239 | 0.000621899 | 59.078 | 80.14 | 0.7416 | 7.94 | 0.98 | 1.03 | 8.2 | ||
27X-2, 150 | 14 | 0.871 | 0.0137 | 0.0116 | 0.000753646 | 49.035 | 74.43 | 0.6481 | 6.94 | 1.19 | 0.71 | 4.9 | ||
27X-2, 150 | 15 | 0.918 | 0.0136 | 0.0145 | 0.000399538 | 81.591 | 87.14 | 0.8001 | 8.57 | 0.71 | 1.97 | 16.8 | ||
27X-2, 150 | 16 | 1.041 | 0.0139 | 0.0118 | 0.000783483 | 41.832 | 77.75 | 0.8090 | 8.66 | 1.39 | 0.52 | 4.5 | ||
27X-2, 150 | 17 | 0.900 | 0.0136 | 0.0068 | 0.000538336 | 84.250 | 82.33 | 0.7413 | 7.94 | 0.69 | 2.10 | 16.6 | ||
8.50 | 0.16 | |||||||||||||
28X-5, 13-14 | 1 | 1.525 | 0.061 | 0.000 | 0.0034 | 100.00 | 1.53 | 8.48 | 6.97 | 0.02 | 0.2 | |||
28X-5, 13-14 | 2 | 1.701 | 0.059 | 0.000 | 0.0035 | 100.00 | 1.70 | 9.46 | 6.80 | 0.02 | 0.2 | |||
28X-5, 13-14 | 3 | 1.905 | 0.058 | 0.000 | 0.0023 | 100.00 | 1.91 | 10.59 | 10.16 | 0.01 | 0.1 | |||
28X-5, 13-14 | 4 | 0.538 | 0.056 | 0.000 | 0.0013 | 100.00 | 0.54 | 2.99 | 17.98 | 0.00 | 0.0 | |||
8.93 | 4.26 | |||||||||||||
40X-1, 57-58 | 1 | 3.270 | 0.062 | 0.002 | 0.0066 | 86.29 | 2.82 | 15.66 | 3.59 | 0.08 | 1.2 | |||
40X-1, 57-58 | 2 | 3.207 | 0.061 | 0.000 | 0.0039 | 100.00 | 3.21 | 17.79 | 6.06 | 0.03 | 0.5 | |||
40X-1, 57-58 | 3 | 3.077 | 0.059 | 0.000 | 0.0009 | 100.00 | 3.08 | 17.07 | 25.66 | 0.00 | 0.0 | |||
16.23 | 3.07 | |||||||||||||
41X-4, 41-42 | 1 | 3.365 | 0.099 | 0.000 | 0.0055 | 100.00 | 3.37 | 18.66 | 4.29 | 0.05 | 1.0 | |||
41X-4, 41-42 | 2 | 4.025 | 0.101 | 0.000 | 0.0037 | 100.00 | 4.02 | 22.30 | 6.44 | 0.02 | 0.5 | |||
41X-4, 41-42 | 3 | 3.504 | 0.100 | 0.000 | 0.0033 | 100.00 | 3.50 | 19.43 | 7.15 | 0.02 | 0.4 | |||
41X-4, 41-42 | 4 | 4.380 | 0.121 | 0.009 | 0.0023 | 41.20 | 1.80 | 10.03 | 16.09 | 0.00 | 0.0 | |||
41X-4, 41-42 | 5 | 3.651 | 0.098 | 0.000 | 0.0021 | 100.00 | 3.65 | 20.24 | 17.49 | 0.00 | 0.1 | |||
41X-4, 41-42 | 6 | 3.840 | 0.096 | 0.000 | 0.0031 | 100.00 | 3.84 | 21.28 | 7.55 | 0.02 | 0.4 | |||
41X-4, 41-42 | 7 | 4.091 | 0.076 | 0.003 | 0.0033 | 77.78 | 3.18 | 17.65 | 7.25 | 0.02 | 0.3 | |||
19.38 | 2.66 | |||||||||||||
45X-2, 94-95 | 1 | 4.137 | 0.079 | 0.003 | 0.0034 | 78.89 | 3.26 | 18.11 | 6.96 | 0.02 | 0.4 | |||
45X-2, 94-95 | 2 | 4.366 | 0.076 | 0.001 | 0.0070 | 90.33 | 3.94 | 21.85 | 3.37 | 0.09 | 1.9 | |||
45X-2, 94-95 | 3 | 4.579 | 0.072 | 0.005 | 0.0020 | 68.17 | 3.12 | 17.32 | 11.62 | 0.01 | 0.1 | |||
45X-2, 94-95 | 4 | 4.082 | 0.086 | 0.004 | 0.0023 | 68.45 | 2.79 | 15.51 | 10.27 | 0.01 | 0.1 | |||
45X-2, 94-95 | 5 | 2.815 | 0.058 | 0.003 | 0.0031 | 65.64 | 1.85 | 10.27 | 7.73 | 0.02 | 0.2 | |||
19.29 | 2.65 | |||||||||||||
48X-6, 42-43 | 1 | 3.936 | 0.091 | 0.003 | 0.0188 | 76.05 | 2.99 | 16.61 | 1.27 | 0.62 | 10.3 | |||
48X-6, 42-43 | 2 | 3.899 | 0.080 | 0.002 | 0.0316 | 85.61 | 3.34 | 18.51 | 0.78 | 1.65 | 30.6 | |||
48X-6, 42-43 | 3 | 3.270 | 0.085 | 0.001 | 0.0165 | 89.07 | 2.91 | 16.17 | 1.45 | 0.47 | 7.7 | |||
48X-6, 42-43 | 4 | 3.664 | 0.077 | 0.002 | 0.0131 | 87.67 | 3.21 | 17.82 | 1.83 | 0.30 | 5.3 | |||
48X-6, 42-43 | 5 | 3.873 | 0.085 | 0.002 | 0.0250 | 87.78 | 3.40 | 18.85 | 1.00 | 1.01 | 19.0 | |||
17.98 | 0.50 |