Bird Rock
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|
step
|
P (W)
|
t (min)
|
40Ar/39Ar
|
38Ar/39Ar
|
37Ar/39Ar
|
36Ar/39Ar
|
39Ar (mol)
|
%40Ar*
|
40Ar*/39ArK
|
Age (Ma)
+sAge
(an)
|
Cl/K
|
Ca/K
|
|
1
|
4
|
1
|
8.994
|
0.014
|
5.70E-01
|
8.98E-04
|
1.44E-14
|
96.8
|
8.748
|
87.0±0.7
|
2.78E-04
|
1.153
|
|
2
|
4
|
1
|
9.499
|
0.027
|
8.30E-03
|
8.47E-04
|
4.45E-14
|
96.8
|
9.212
|
91.5±0.5
|
3.90E-03
|
0.017
|
|
3
|
4
|
1
|
8.842
|
0.015
|
-5.29E-03
|
4.50E-04
|
4.60E-14
|
97.9
|
8.672
|
86.3±0.4
|
3.43E-04
|
-0.011
|
|
4
|
4
|
1
|
8.218
|
0.014
|
-1.92E-03
|
2.36E-04
|
4.07E-14
|
98.5
|
8.111
|
80.8±0.5
|
1.80E-04
|
-0.004
|
|
5
|
4
|
1
|
8.970
|
0.016
|
-5.27E-03
|
-2.95E-05
|
9.66E-14
|
99.3
|
8.941
|
88.9±0.7
|
7.91E-04
|
-0.011
|
|
6
|
4
|
1
|
8.549
|
0.013
|
-4.12E-03
|
2.61E-04
|
5.26E-14
|
98.5
|
8.434
|
84.0±0.4
|
6.40E-05
|
-0.008
|
|
7
|
4
|
1
|
8.613
|
0.013
|
-1.72E-03
|
-9.47E-06
|
3.89E-14
|
99.4
|
8.579
|
85.4±0.5
|
-1.51E-04
|
-0.003
|
|
8
|
4
|
1
|
9.197
|
0.013
|
4.38E-03
|
6.10E-04
|
2.28E-14
|
97.4
|
8.980
|
89.3±0.5
|
-5.61E-05
|
0.009
|
|
9
|
4
|
1
|
8.813
|
0.013
|
2.10E-03
|
5.76E-04
|
2.97E-14
|
97.5
|
8.606
|
85.7±0.4
|
-6.22E-05
|
0.004
|
|
10
|
4
|
1
|
9.541
|
0.014
|
-4.74E-03
|
6.82E-04
|
3.03E-14
|
97.2
|
9.302
|
92.4±0.6
|
3.21E-04
|
-0.010
|
|
11
|
4
|
1
|
8.933
|
0.014
|
-5.46E-03
|
4.40E-04
|
3.09E-14
|
97.9
|
8.765
|
87.2±0.4
|
1.00E-04
|
-0.011
|
|
12
|
4
|
1
|
8.344
|
0.013
|
-6.58E-04
|
2.08E-04
|
2.51E-14
|
98.6
|
8.245
|
82.1±0.4
|
-1.33E-04
|
-0.001
|
|
13
|
4
|
1
|
8.349
|
0.014
|
-2.51E-04
|
1.80E-04
|
4.76E-14
|
98.7
|
8.258
|
82.3±0.4
|
2.44E-04
|
-0.001
|
|
14
|
4
|
1
|
8.441
|
0.013
|
2.93E-03
|
2.39E-04
|
4.71E-14
|
98.5
|
8.333
|
83.0±0.4
|
-1.61E-04
|
0.006
|
|
15
|
4
|
1
|
8.296
|
0.014
|
1.30E-02
|
8.69E-04
|
1.91E-14
|
96.2
|
8.003
|
79.8±0.6
|
1.21E-04
|
0.026
|
|
16
|
4
|
1
|
8.357
|
0.014
|
1.14E-02
|
5.77E-04
|
2.99E-14
|
97.3
|
8.150
|
81.2±0.4
|
3.07E-04
|
0.023
|
|
17
|
4
|
1
|
10.65
|
0.036
|
-1.32E-02
|
1.21E-04
|
5.83E-14
|
99.1
|
10.58
|
104.7±0.6
|
6.27E-03
|
-0.027
|
|
18
|
4
|
1
|
8.955
|
0.012
|
8.52E-03
|
4.26E-04
|
1.65E-14
|
97.8
|
8.792
|
87.5±0.6
|
-2.35E-04
|
0.017
|
|
19
|
4
|
1
|
8.234
|
0.013
|
-2.97E-03
|
2.48E-04
|
2.43E-14
|
98.4
|
8.123
|
81.0±0.5
|
-1.09E-04
|
-0.006
|
|
20
|
4
|
1
|
10.21
|
0.015
|
5.99E-03
|
4.01E-04
|
2.13E-14
|
98.1
|
10.06
|
99.7±0.9
|
3.66E-04
|
0.012
|
|
21
|
4
|
1
|
10.070
|
0.013
|
-1.36E-03
|
4.33E-04
|
2.32E-14
|
98.1
|
9.905
|
98.2±0.5
|
2.83E-05
|
-0.003
|
|
22
|
4
|
1
|
9.299
|
0.016
|
1.73E-02
|
5.21E-04
|
2.53E-14
|
97.7
|
9.109
|
90.5±0.5
|
6.92E-04
|
0.035
|
|
23
|
4
|
1
|
8.859
|
0.014
|
8.57E-03
|
1.28E-04
|
3.19E-14
|
98.9
|
8.785
|
87.4±0.5
|
2.79E-04
|
0.017
|
|
24
|
4
|
1
|
9.118
|
0.015
|
6.78E-03
|
4.10E-04
|
3.29E-14
|
98.0
|
8.960
|
89.1±0.5
|
4.25E-04
|
0.014
|
|
25
|
4
|
1
|
8.704
|
0.015
|
-7.14E-03
|
3.24E-04
|
1.75E-14
|
98.1
|
8.571
|
85.3±0.7
|
3.71E-04
|
-0.014
|
|
26
|
4
|
1
|
9.126
|
0.015
|
5.21E-03
|
2.87E-04
|
2.73E-14
|
98.3
|
9.004
|
89.5±0.6
|
4.10E-04
|
0.011
|
|
27
|
4
|
1
|
8.195
|
0.013
|
-6.80E-03
|
4.83E-05
|
4.50E-14
|
99.1
|
8.143
|
81.1±0.4
|
3.63E-05
|
-0.014
|
|
28
|
4
|
1
|
7.984
|
0.014
|
4.43E-03
|
3.60E-04
|
5.92E-14
|
98.0
|
7.841
|
78.2±0.4
|
9.45E-05
|
0.009
|
|
29
|
4
|
1
|
9.964
|
0.014
|
-3.80E-03
|
1.64E-04
|
7.04E-14
|
98.9
|
9.878
|
98.0±0.5
|
1.02E-04
|
-0.008
|
|
30
|
4
|
1
|
9.365
|
0.014
|
-3.02E-03
|
2.14E-04
|
5.43E-14
|
98.8
|
9.265
|
92.0±0.4
|
1.79E-04
|
-0.006
|
|
31
|
4
|
1
|
8.189
|
0.013
|
-1.16E-03
|
3.29E-04
|
1.89E-14
|
98.0
|
8.055
|
80.3±0.6
|
7.93E-06
|
-0.002
|
|
32
|
4
|
1
|
9.149
|
0.016
|
3.26E-03
|
2.44E-04
|
2.56E-14
|
98.6
|
9.040
|
89.9±0.4
|
6.92E-04
|
0.007
|
|
33
|
4
|
1
|
8.623
|
0.013
|
4.92E-03
|
2.97E-04
|
3.36E-14
|
98.3
|
8.498
|
84.6±0.6
|
-1.82E-04
|
0.010
|
|
34
|
4
|
1
|
8.623
|
0.014
|
-1.36E-02
|
3.31E-05
|
3.53E-14
|
99.2
|
8.574
|
85.3±0.5
|
2.90E-04
|
-0.028
|
|
35
|
4
|
1
|
8.341
|
0.014
|
7.46E-03
|
1.82E-04
|
4.61E-14
|
98.7
|
8.251
|
82.2±0.4
|
2.46E-04
|
0.015
|
|
36
|
4
|
1
|
8.145
|
0.013
|
5.13E-03
|
2.94E-04
|
2.84E-14
|
98.3
|
8.022
|
80.0±0.4
|
-1.41E-05
|
0.010
|
|
37
|
4
|
1
|
9.293
|
0.015
|
-8.85E-03
|
8.34E-04
|
3.04E-14
|
96.7
|
9.009
|
89.6±0.6
|
4.69E-04
|
-0.018
|
|
38
|
4
|
1
|
8.985
|
0.014
|
2.47E-02
|
4.68E-04
|
2.93E-14
|
97.8
|
8.812
|
87.7±0.6
|
1.31E-04
|
0.050
|
|
39
|
4
|
1
|
8.389
|
0.016
|
4.43E-03
|
2.31E-04
|
2.41E-14
|
98.5
|
8.284
|
82.5±0.5
|
8.87E-04
|
0.009
|
|
40
|
4
|
1
|
7.987
|
0.013
|
-6.10E-03
|
3.49E-04
|
2.12E-14
|
97.9
|
7.846
|
78.3±0.6
|
-8.09E-07
|
-0.012
|
|
41
|
4
|
1
|
8.083
|
0.013
|
1.74E-03
|
3.06E-04
|
3.10E-14
|
98.2
|
7.956
|
79.3±0.4
|
4.72E-05
|
0.004
|
|
42
|
4
|
1
|
8.907
|
0.022
|
-2.69E-03
|
1.25E-03
|
2.79E-14
|
95.2
|
8.499
|
84.6±0.4
|
2.43E-03
|
-0.005
|
|
43
|
4
|
1
|
10.53
|
0.019
|
-6.79E-04
|
7.80E-04
|
2.08E-14
|
97.2
|
10.26
|
101.7±0.6
|
1.48E-03
|
-0.001
|
|
44
|
4
|
1
|
8.128
|
0.014
|
-9.49E-03
|
1.34E-04
|
2.46E-14
|
98.8
|
8.051
|
80.2±0.4
|
9.42E-05
|
-0.019
|
|
45
|
4
|
1
|
8.606
|
0.014
|
-8.88E-03
|
4.35E-04
|
1.16E-14
|
97.6
|
8.439
|
84.0±0.9
|
1.71E-04
|
-0.018
|
|
46
|
4
|
1
|
9.764
|
0.017
|
-2.54E-03
|
-1.56E-04
|
4.90E-14
|
99.9
|
9.773
|
97.0±0.5
|
9.73E-04
|
-0.005
|
|
47
|
4
|
1
|
7.983
|
0.013
|
-1.09E-02
|
-1.94E-04
|
1.14E-14
|
99.7
|
8.003
|
79.8±1.0
|
1.06E-06
|
-0.022
|
|
48
|
4
|
1
|
9.058
|
0.016
|
4.60E-01
|
9.28E-04
|
2.30E-14
|
96.7
|
8.792
|
87.5±0.4
|
7.26E-04
|
0.930
|
|
49
|
4
|
1
|
10.69
|
0.016
|
1.41E-02
|
1.65E-03
|
3.04E-14
|
94.9
|
10.16
|
100.7±0.3
|
6.40E-04
|
0.029
|
|
50
|
4
|
1
|
9.172
|
0.017
|
3.81E-03
|
1.24E-03
|
3.45E-14
|
95.4
|
8.769
|
87.2±0.2
|
9.88E-04
|
0.008
|
|
51
|
4
|
1
|
9.426
|
0.017
|
8.66E-03
|
8.65E-04
|
4.20E-14
|
96.6
|
9.134
|
90.8±0.3
|
1.04E-03
|
0.017
|
|
52
|
4
|
1
|
11.11
|
0.031
|
2.45E+00
|
8.39E-03
|
6.30E-15
|
78.5
|
8.837
|
87.9±1.1
|
4.68E-03
|
4.965
|
|
53
|
4
|
1
|
8.989
|
0.018
|
2.21E-01
|
6.49E-04
|
5.54E-14
|
97.4
|
8.782
|
87.4±0.2
|
1.34E-03
|
0.447
|
|
54
|
4
|
1
|
8.532
|
0.014
|
-2.52E-03
|
3.70E-04
|
1.19E-14
|
97.5
|
8.385
|
83.5±0.4
|
1.18E-04
|
-0.005
|
|
55
|
4
|
1
|
9.067
|
0.021
|
1.09E-02
|
4.77E-04
|
5.73E-14
|
97.8
|
8.890
|
88.4±0.2
|
2.04E-03
|
0.022
|
|
56
|
4
|
1
|
9.282
|
0.015
|
8.33E-03
|
7.25E-04
|
4.25E-14
|
97.0
|
9.032
|
89.8±0.2
|
4.62E-04
|
0.017
|
|
57
|
4
|
1
|
18.11
|
0.078
|
4.98E-01
|
3.56E-02
|
6.08E-15
|
41.7
|
7.598
|
75.8±2.6
|
1.62E-02
|
1.006
|
|
58
|
4
|
1
|
10.93
|
0.107
|
4.94E-02
|
7.06E-04
|
1.17E-14
|
97.2
|
10.69
|
105.8±0.5
|
2.59E-02
|
0.100
|
|
59
|
4
|
1
|
9.788
|
0.030
|
1.64E-03
|
1.04E-03
|
4.21E-14
|
96.2
|
9.445
|
93.8±0.3
|
4.55E-03
|
0.003
|
|
60
|
4
|
1
|
9.581
|
0.017
|
8.94E-03
|
1.02E-03
|
2.77E-14
|
96.0
|
9.243
|
91.8±0.4
|
1.01E-03
|
0.018
|
|
61
|
4
|
1
|
8.017
|
0.013
|
7.15E-03
|
5.81E-04
|
2.98E-14
|
97.1
|
7.809
|
77.9±0.2
|
3.63E-05
|
0.014
|
|
62
|
4
|
1
|
8.724
|
0.018
|
2.19E-02
|
5.49E-04
|
3.88E-14
|
97.4
|
8.527
|
84.9±0.3
|
1.36E-03
|
0.044
|
|
63
|
4
|
1
|
8.794
|
0.015
|
7.25E-03
|
4.86E-04
|
4.64E-14
|
97.7
|
8.614
|
85.7±0.2
|
4.00E-04
|
0.015
|
|
64
|
4
|
1
|
9.064
|
0.015
|
5.61E-03
|
7.09E-04
|
5.60E-14
|
97.0
|
8.818
|
87.7±0.2
|
5.90E-04
|
0.011
|
|
65
|
4
|
1
|
9.274
|
0.015
|
2.03E-02
|
4.46E-04
|
4.61E-14
|
97.9
|
9.107
|
90.5±0.2
|
4.08E-04
|
0.041
|
|
66
|
4
|
1
|
10.59
|
0.020
|
7.64E-01
|
3.57E-04
|
5.73E-15
|
98.1
|
10.52
|
104.2±1.0
|
1.88E-03
|
1.543
|
|
67
|
4
|
1
|
8.844
|
0.015
|
3.01E-03
|
2.93E-04
|
3.76E-14
|
98.2
|
8.721
|
86.8±0.4
|
5.33E-04
|
0.006
|
|
68
|
4
|
1
|
8.513
|
0.016
|
1.22E-03
|
1.57E-03
|
3.65E-14
|
93.9
|
8.012
|
79.9±0.2
|
6.68E-04
|
0.002
|
|
69
|
4
|
1
|
8.627
|
0.014
|
1.83E-02
|
3.43E-04
|
6.38E-14
|
98.2
|
8.490
|
84.5±0.2
|
1.52E-04
|
0.037
|
|
70
|
4
|
1
|
8.859
|
0.016
|
1.41E-02
|
4.57E-04
|
3.08E-14
|
97.8
|
8.688
|
86.5±0.3
|
6.14E-04
|
0.029
|
|
71
|
4
|
1
|
7.499
|
0.018
|
3.17E+00
|
1.18E-03
|
5.98E-15
|
97.1
|
7.419
|
74.1±1.0
|
1.43E-03
|
6.413
|
|
72
|
4
|
1
|
9.064
|
0.015
|
2.99E-03
|
3.88E-04
|
1.44E-14
|
97.8
|
8.913
|
88.6±0.5
|
5.40E-04
|
0.006
|