40Ar/39Ar Data for Ressel et al (Beast - Eocene)

ID 40Ar/39Ar 37Ar/39Ar 36Ar/39Ar 39ArK K/Ca Cl/K %40Ar* Age ±2s    
      (x 10-3) (x 10-15 mol)       (Ma) (Ma)    
                       
BST-114, B2:93, single crystal, J=0.000785599±0.10%, D=1.00292±0.00118, NM-93, Lab#=9468                      
2 27.37 0.0039 4.213 4.44 129.9 -0.101 95.4 36.65 0.41    
1 27.36 0.0038 3.166 1.69 133.0 0.094 96.6 37.07 0.16    
3 27.54 0.0036 3.596 2.83 141.2 1.2 96.1 37.13 0.39    
13 27.48 0.0054 3.151 3.07 95.0 0.29 96.6 37.24 0.16    
8 27.46 0.0039 2.990 6.44 130.1 0.30 96.8 37.28 0.17    
9 26.95 0.0039 1.161 6.80 131.0 0.37 98.7 37.32 0.14    
12 27.48 0.0088 2.834 3.21 58.0 0.30 97.0 37.37 0.21    
10 27.41 0.0053 2.540 4.96 97.0 0.51 97.3 37.39 0.18    
5 27.18 0.0005 1.713 3.40 990.2 -0.053 98.1 37.41 0.42    
15 27.54 0.0034 2.869 1.66 151.1 0.41 96.9 37.44 0.18    
4 27.26 0.0007 1.791 3.64 698.0 0.12 98.1 37.49 0.40    
11 27.98 0.0051 4.127 6.86 100.1 0.34 95.6 37.53 0.18    
14 27.67 0.0043 3.065 3.47 118.0 0.39 96.7 37.54 0.20    
6 27.65 0.0006 2.896 2.54 815.4 0.27 96.9 37.59 0.55    
7 27.51 0.0000 2.131 2.57 - 0.080 97.7 37.70 0.54    
mean ± sdev     n=14   281.4 ±620.4     37.39 0.36    
mean ± SEM     n=14   281.4 ±620.4     37.39 0.12    
weighted mean ± Taylor err     n=14   281.4 ±620.4     37.343 0.091    
weighted mean ± S & A err     n=14   281.4 ±620.4     37.34 0.12    
                       
Rich-10, C5:101, single crystal sanidine, J=0.000763798±0.10%, D=1.00361±0.00157, NM-101, Lab#=9960                      
13 28.85 0.0081 5.849 2.46 62.7 0.000 94.0 36.997 0.093    
15 33.05 0.0084 19.91 1.74 60.5 0.001 82.2 37.05 0.13    
10 32.14 0.0097 16.52 4.50 52.7 0.001 84.8 37.18 0.10    
08 32.43 0.0051 17.27 3.89 100.5 0.000 84.3 37.26 0.12    
09 30.04 0.0055 9.087 5.19 93.3 0.000 91.1 37.30 0.10    
11 30.51 0.0048 10.65 2.48 107.2 0.000 89.7 37.32 0.10    
12 32.10 0.0070 15.97 4.65 73.2 0.000 85.3 37.34 0.11    
07 34.04 0.0034 22.52 4.61 151.3 0.000 80.4 37.34 0.11    
03 31.34 0.0162 13.33 2.74 31.5 0.000 87.4 37.37 0.11    
04 29.64 0.0044 7.437 4.01 115.1 0.000 92.6 37.419 0.097    
05 33.94 0.0045 21.92 3.28 113.0 0.000 80.9 37.45 0.13    
06 31.93 0.0051 15.06 2.44 99.7 0.000 86.1 37.48 0.12    
14 31.97 0.0057 15.13 2.39 89.1 0.000 86.0 37.50 0.11    
01 31.91 0.0057 14.80 3.97 89.4 0.000 86.3 37.55 0.14    
02 30.69 0.0063 10.38 3.23 81.0 0.000 90.0 37.67 0.10    
weighted mean ± Taylor err     n=15   88.0 ±29.5     37.340 0.090    
                       
H97-22b, B11:81, single crystal sanidine, J=0.000812318±0.09%, D=1.0052±0.00069, NM-81, Lab#=8637                      
5 27.04 5.068 13.42 0.237 0.10 -0.535 86.8 34.2 1.3    
14 26.99 0.0057 5.107 7.65 89.5 0.19 94.4 36.96 0.15    
15 25.81 0.0042 1.030 5.10 120.6 0.57 98.8 36.99 0.17    
11 25.79 0.0042 0.7981 14.5 121.3 0.31 99.1 37.06 0.13    
12 25.74 0.0039 0.5678 9.32 129.6 0.24 99.3 37.09 0.11    
3 25.76 0.0051 0.6037 16.4 100.5 0.31 99.3 37.11 0.10    
9 25.69 0.0047 0.2852 17.9 108.4 0.38 99.7 37.14 0.14    
13 25.87 0.0037 0.8862 18.5 137.2 0.30 99.0 37.14 0.11    
4 25.94 0.0044 0.8943 13.5 114.9 0.35 99.0 37.24 0.12    
10 25.76 0.0047 0.2849 15.1 109.2 0.30 99.7 37.24 0.12    
2 25.91 0.0044 0.6403 12.1 115.4 0.38 99.3 37.31 0.12    
1 25.96 0.0040 0.7355 7.21 127.5 0.26 99.2 37.33 0.13    
6 27.23 0.0045 5.003 11.9 112.6 0.31 94.6 37.35 0.13    
7 25.87 0.0040 0.2893 4.29 129.1 0.14 99.7 37.39 0.17    
8 25.90 0.0037 0.3241 9.53 138.5 0.24 99.6 37.43 0.17    
mean ± sdev     n=14   118.2 ±27.6     37.2 0.3    
mean ± SEM     n=14   118.2 ±27.6     37.20 0.11    
weighted mean ± Taylor err     n=14   118.2 ±27.6     37.190 0.078    
weighted mean ± S & A err     n=14   118.2 ±27.6     37.19 0.11    
                       
                       
                       
                       
                       
ID Temp 40Ar/39Ar 37Ar/39Ar 36Ar/39Ar 39ArK K/Ca Cl/K 40Ar* 39Ar Age ±2s
  (°C)     (x 10-3) (x 10-15 mol)   (x 10-3) (%) (%) (Ma) (Ma)
                       
G11-005-4-4492, C4:101, 4.29mg bi, J=0.000763599±0.10%, D=1.00361±0.00157, NM-101, Lab#=9959-02                      
A 650 136.9 0.3304 407.3 0.076 1.5 2.4 12.1 0.4 22.7 5.0
B 750 61.78 0.0868 119.7 0.221 5.9 2.4 42.8 1.5 36.0 1.3
C 850 31.50 0.0092 9.949 1.14 55.5 0.45 90.7 7.1 38.92 0.26
D 920 29.67 0.0056 2.511 1.91 91.6 0.55 97.5 16.5 39.42 0.19
E 1000 29.33 0.0097 1.663 1.78 52.5 0.29 98.3 25.2 39.30 0.18
F 1075 29.14 0.0146 1.079 2.84 34.9 0.28 98.9 39.2 39.27 0.18
G 1110 29.12 0.0197 1.171 1.86 25.9 0.53 98.8 48.3 39.22 0.18
H 1180 29.03 0.0580 1.384 2.88 8.8 0.37 98.6 62.5 39.01 0.18
I 1210 29.09 0.0722 1.020 6.29 7.1 0.44 99.0 93.4 39.23 0.17
J 1250 29.50 0.0468 1.566 1.13 10.9 0.85 98.4 99.0 39.57 0.21
K 1300 31.44 0.1292 3.473 0.166 3.9 0.65 96.8 99.8 41.43 0.62
L 1650 112.6 6.254 119.8 0.044 0.082 59.82 69.0 100.0 104.4 4.4
total gas age     n=12   20.3 27.7       39.29 0.22
plateau     n=5 steps E-I 15.6 19.8     76.9 39.21 0.15
                       
BP-2, h5#4:81, biotite, 7.76 mg, J=0.000807327±0.09%, D=1.0052±0.00069, NM-81, Lab#=8662-01                      
A 650 1685.8 0.0742 5538.25 0.223 6.9 -3.85 2.9 0.2 70.4 116.7
B 750 87.75 0.0245 205.8 1.17 20.8 0.22 30.7 1.2 38.8 1.9
C 850 39.90 0.0040 42.90 7.97 127.2 0.37 68.2 7.8 39.23 0.28
D 920 30.12 0.0051 9.199 8.66 100.8 0.47 91.0 15.1 39.48 0.19
E 1000 28.82 0.0040 5.691 10.0 127.9 0.34 94.2 23.5 39.10 0.18
F 1075 28.83 0.0039 4.972 8.43 130.7 0.49 94.9 30.5 39.42 0.15
G 1110 28.44 0.0047 4.431 12.1 108.0 0.22 95.4 40.7 39.10 0.16
H 1180 28.31 0.0125 4.938 24.1 40.9 0.30 94.8 60.8 38.70 0.13
I 1210 28.27 0.0121 4.818 22.8 42.2 0.21 95.0 80.0 38.68 0.18
J 1250 28.66 0.0265 5.384 18.7 19.3 0.32 94.5 95.6 39.00 0.12
K 1300 28.81 0.0193 5.205 4.85 26.4 0.39 94.7 99.7 39.29 0.17
L 1650 48.06 0.0000 38.10 0.385 - 0.13 76.6 100.0 52.8 1.2
total gas age     n=12   119.3 67.3       39.09 0.40
plateau     n=9 steps C-K 117.6 68.1     98.5 39.07 0.21
                       
BP-2, h6#6:81, plag, 31.13 mg, J=0.000807418±0.09%, D=1.0052±0.00069, NM-81, Lab#=8663-01                      
A 625 15131.77 0.0367 49778.63 0.308 13.9 64.49 2.8 1.0 529.2 #####
B 700 114.8 1.174 297.0 0.797 0.43 0.77 23.6 3.6 39.2 2.9
C 750 57.54 1.957 87.04 0.054 0.26 5.2 55.6 3.8 46.0 9.1
D 800 44.50 2.623 51.91 1.35 0.19 0.22 66.0 8.3 42.35 0.80
E 875 31.78 4.149 15.37 1.75 0.12 0.28 86.7 14.1 39.82 0.43
F 975 29.58 5.975 10.52 3.94 0.085 0.27 91.0 27.1 38.97 0.24
G 1075 29.78 7.658 13.00 2.36 0.067 0.71 89.1 34.9 38.44 0.34
H 1250 30.91 6.965 17.81 9.70 0.073 0.36 84.7 66.9 37.92 0.17
I 1350 36.56 6.617 35.81 4.63 0.077 0.077 72.4 82.2 38.35 0.40
J 1650 33.29 8.598 24.07 5.40 0.059 0.22 80.6 100.0 38.91 0.25
total gas age     n=10   30.3 0.23       43.7 15.3
plateau     n=3 steps G-I 16.7 0.07     55.1 38.10 0.37
                       
BP-2, h3:81, wr, 6.70 mg, J=0.000807202±0.09%, D=1.0052±0.00069, NM-81, Lab#=8660-01                      
A 625 11919.6 0.0822 37770.10 2.22 6.2 72.4 6.4 7.5 861.7 685.3
B 0 62.76 0.0737 96.30 5.83 6.9 0.69 54.7 27.3 49.29 0.22
BB 700 52.32 0.0825 61.94 0.496 6.2 0.97 65.0 29.0 48.9 1.2
C 750 40.55 0.0983 22.93 1.28 5.2 0.32 83.3 33.3 48.54 0.60
D 800 34.14 0.1093 9.710 2.39 4.7 0.20 91.6 41.4 44.99 0.32
E 875 31.07 0.1282 4.893 4.43 4.0 -0.124 95.4 56.4 42.65 0.19
F 975 29.24 0.1967 3.213 4.49 2.6 0.20 96.8 71.6 40.76 0.18
G 1075 29.21 0.3487 4.837 2.03 1.5 0.25 95.2 78.5 40.05 0.31
H 1170 30.70 0.4452 10.37 3.24 1.1 0.045 90.1 89.5 39.87 0.23
I 1250 43.30 0.6506 51.74 1.53 0.78 0.094 64.8 94.6 40.42 0.61
J 1650 63.35 1.474 115.1 1.58 0.35 -0.094 46.5 100.0 42.45 0.96
total gas age     n=11   29.5 3.8       105.3 51.9
plateau     n=11 steps A-J 29.5 3.8     100.0 42.9 2.1
                       
DS-13 Whole rock B:3, Rhyolite WR, 12.70 mg, J=0.000786178±0.10%, D=1.00362±0.00105, nm-93, Lab#=9469-01                      
A 600 532.0 0.3611 1743.9 0.429 1.4 3.4 3.1 1.2 23.6 9.1
B 700 76.64 0.5754 177.8 3.17 0.89 0.69 31.5 10.0 33.94 0.84
C 750 41.27 1.089 48.65 3.21 0.47 0.52 65.4 18.9 37.90 0.36
D 800 32.71 1.033 15.37 2.57 0.49 -0.167 86.4 26.1 39.65 0.24
E 850 30.26 0.1826 7.008 3.81 2.8 0.070 93.2 36.7 39.57 0.21
F 900 29.61 0.0535 5.596 3.45 9.5 0.19 94.4 46.3 39.23 0.19
G 950 34.79 0.0323 25.24 3.17 15.8 0.040 78.6 55.1 38.37 0.27
H 1000 29.51 0.0268 6.751 1.78 19.0 0.13 93.2 60.0 38.61 0.21
I 1050 29.50 0.0308 8.376 2.65 16.5 0.17 91.6 67.4 37.93 0.20
J 1100 30.27 0.0213 10.49 2.11 24.0 0.47 89.8 73.3 38.13 0.23
K 1150 31.00 0.0230 13.65 2.59 22.2 0.37 87.0 80.5 37.86 0.23
L 1250 33.41 0.0416 22.55 3.03 12.3 0.46 80.1 88.9 37.55 0.21
M 1400 35.20 0.0412 30.87 3.76 12.4 0.26 74.1 99.4 36.62 0.29
N 1650 97.25 0.0229 250.3 0.232 22.3 2.6 23.9 100.0 32.7 2.7
total gas age     n=14   35.9 10.4       37.70 0.42
plateau     n=14 steps A-N 35.9 10.4     100.0 38.38 0.53
                       
BST-114 B:2, Sanidine, 10.06 mg, J=0.000785599±0.10%, D=1.00362±0.00105, NM-93, Lab#=9468-01                      
A 700 328.3 0.1264 1052.78 0.094 4.0 4.8 5.2 0.1 24.2 11.1
B 800 47.20 0.0165 72.91 0.525 30.9 0.95 54.4 0.8 35.99 0.78
C 900 28.53 0.0073 6.473 1.52 69.7 0.70 93.3 2.8 37.33 0.18
D 1000 27.62 0.0057 3.143 3.54 90.0 0.38 96.6 7.4 37.44 0.16
E 1100 26.93 0.0048 1.011 5.85 105.4 0.32 98.9 15.0 37.35 0.13
F 1200 26.96 0.0057 0.7852 7.60 89.2 0.28 99.1 25.0 37.49 0.15
G 1250 27.24 0.0048 2.067 5.92 106.3 0.20 97.8 32.7 37.35 0.13
H 1300 27.10 0.0044 1.858 13.9 115.7 0.20 98.0 50.8 37.24 0.15
I 1350 27.75 0.0047 3.995 12.0 108.1 0.29 95.7 66.5 37.28 0.15
J 1400 27.44 0.0055 2.273 5.30 93.5 0.33 97.6 73.4 37.54 0.16
K 1500 27.55 0.0070 2.648 6.17 72.8 0.31 97.2 81.5 37.54 0.12
L 1600 27.64 0.0054 2.741 8.77 93.7 0.28 97.1 92.9 37.63 0.15
M 1800 31.22 0.0088 14.80 5.19 57.7 0.20 86.0 99.7 37.65 0.18
N 1800 79.44 0.0661 181.4 0.224 7.7 -0.09 32.5 100.0 36.3 1.8
total gas age     n=14   76.7 95.8       37.39 0.17
plateau     n=8 steps C-J 55.7 103.4     72.6 37.37 0.11
                       
BST-30, h4#2:81, biotite, 6.82 mg, J=0.00080722±0.09%, D=1.0052±0.00069, NM-81, Lab#=8661-01                      
A 650 97.40 0.4520 249.7 1.24 1.1 1.7 24.3 1.2 34.1 1.5
B 750 66.75 0.1481 138.1 3.65 3.4 0.39 38.9 4.7 37.42 0.70
C 850 30.89 0.0070 16.52 7.87 72.8 0.17 84.2 12.2 37.48 0.19
D 920 28.30 0.0062 6.933 8.10 82.4 0.28 92.8 20.0 37.82 0.16
E 1000 27.90 0.0065 5.977 7.00 78.0 0.14 93.7 26.7 37.66 0.17
F 1075 28.05 0.0069 6.343 12.9 74.1 0.25 93.3 39.0 37.72 0.13
G 1110 27.36 0.0056 4.984 12.7 90.4 0.022 94.6 51.2 37.32 0.17
H 1180 27.39 0.0082 5.011 20.6 62.0 0.40 94.6 70.9 37.35 0.15
I 1210 27.44 0.0149 5.503 21.2 34.2 0.43 94.1 91.2 37.21 0.13
J 1250 28.08 0.0511 7.203 8.70 10.0 0.22 92.4 99.6 37.41 0.18
K 1300 28.36 0.1044 3.069 0.386 4.9 0.68 96.8 99.9 39.55 1.00
L 1650 91.30 0.0612 185.3 0.079 8.3 -0.50 40.0 100.0 52.5 8.9
total gas age     n=12   104.5 57.4       37.42 0.20
plateau     n=4 steps G-J 63.2 51.2     60.5 37.31 0.14
                       
H97-21, c4:81, hornblende, 4.97 mg, J=0.000811158±0.09%, D=1.0052±0.00069, NM-81, Lab#=8646-01                      
A 800 473.8 2.162 1531.73 0.133 0.24 4.8 4.5 2.1 31.0 25.3
B 850 49.51 0.8808 81.19 0.119 0.58 6.0 51.7 4.1 37.1 3.7
C 950 31.33 0.6296 28.34 0.176 0.81 -0.59 73.4 6.9 33.4 2.2
D 1020 28.99 0.7209 13.95 0.159 0.71 1.5 86.0 9.5 36.1 2.4
E 1080 28.45 2.040 17.63 0.123 0.25 -0.63 82.2 11.5 34.0 3.0
F 1120 30.00 5.571 11.82 0.261 0.092 2.1 89.8 15.7 39.1 1.6
G 1160 29.30 7.608 12.40 1.95 0.067 1.1 89.5 47.2 38.18 0.31
H 1200 27.65 6.708 5.842 2.42 0.076 0.72 95.6 86.2 38.46 0.27
I 1300 28.99 8.009 11.29 0.819 0.064 0.56 90.6 99.5 38.25 0.57
J 1400 99.91 8.724 199.0 0.017 0.058 6.0 41.8 99.7 60.5 25.4
K 1650 281.6 2.637 617.2 0.016 0.19 -9.35 35.3 100.0 140.1 64.7
total gas age     n=11   6.19 0.13       38.2 1.4
plateau     n=5 steps F-J 5.47 0.07     88.3 38.34 0.33
                       
WC-31, D2:101, 26.23mg plag, J=0.000762051±0.10%, D=1.00361±0.00157, NM-101, Lab#=9950-01                      
A 650 436.3 1.789 1303.68 0.125 0.29 17.94 11.7 0.5 69.2 10.8
B 750 44.93 0.7808 57.19 2.02 0.65 0.29 62.5 8.3 38.23 0.43
C 825 32.79 0.7404 12.84 1.69 0.69 0.83 88.6 14.8 39.53 0.24
D 900 31.84 0.6741 12.28 2.25 0.76 0.46 88.8 23.4 38.46 0.21
E 1000 31.77 0.4594 12.10 2.70 1.1 0.26 88.9 33.8 38.41 0.21
F 1100 33.86 0.3200 19.19 3.42 1.6 0.58 83.3 47.0 38.39 0.26
G 1250 32.59 0.3001 15.75 7.65 1.7 0.34 85.8 76.4 38.05 0.23
H 1450 34.11 2.845 17.44 5.79 0.18 1.3 85.5 98.7 39.75 0.22
I 1650 45.55 3.487 35.16 0.330 0.15 8.0 77.8 100.0 48.18 0.64
total gas age     n=9   26.0 1.0       38.93 0.30
plateau     n=4 steps D-G 16.0 1.4     61.7 38.34 0.23
                       
BST-144, C6:101, 9.45mg alunite, J=0.000763799±0.10%, D=1.00361±0.00157, NM-101, Lab#=9961-02                      
A 1 127.0 0.0000 361.5 0.012 - 15.6 15.9 0.9 27.5 16.9
B 1 174.7 0.0000 480.2 0.009 - 19.9 18.8 1.6 44.7 26.5
C 2 65.97 0.0000 159.5 0.007 - 0.20 28.5 2.1 25.7 15.4
D 2 271.3 0.0638 892.0 0.104 8.0 2.6 2.8 10.3 10.6 9.5
E 2 55.43 0.0857 139.5 0.086 6.0 2.3 25.7 17.0 19.5 2.3
F 3 39.77 0.0690 89.37 0.150 7.4 0.16 33.6 28.8 18.3 1.3
G 3 99.57 0.0000 260.1 0.004 - 7.4 22.8 29.2 31.0 26.6
H 3 33.41 0.0484 77.36 0.012 10.5 10.9 31.6 30.1 14.5 8.0
I 4 57.14 0.0684 149.0 0.653 7.5 0.009 23.0 81.3 18.0 1.1
J 4 29.62 0.0808 51.19 0.104 6.3 -0.626 48.9 89.5 19.9 1.7
K 4 21.95 0.0883 33.24 0.134 5.8 1.0 55.3 100.0 16.6 1.1
total gas age     n=11   1.28 7.1       17.9 2.5
plateau     n=10 steps A-J 1.14 7.3     89.5 18.6 1.2
                       
Isotopic ratios corrected for blank, radioactive decay, and mass discrimination, not corrected for interferring reactions.                      
Individual analyses show analytical error only; mean age errors also include error in J and irradiation parameters.                      
Analyses in italics are excluded excluded from mean age calculations.                      
Correction factors:                      
(39Ar/37Ar)Ca = 0.00070±0.00005                      
(36Ar/37Ar)Ca = 0.00026±0.00002                      
(38Ar/39Ar)K = 0.0119                      
(40Ar/39Ar)K = 0.0002±0.0003                      

Last Updated on 9/8/99
By Chris Henry