LF-23-9800 K-feldspar (J = 0.000427) Total gas age = 0.89 ± 0.01Ma

step

T

(° C)

⁴⁰Ar/³⁹Ar

³⁷Ar/³⁹Ar

³⁶Ar/³⁹Ar

³⁹Ar

(mol)

S³⁹Ar

(%)

⁴⁰Ar*

(%)

Age ± 1s

(Ma)

1

450

26.21

2.54E-01

7.41E-02

6.63E-15

2.60

16.5

3.32 ± 0.09

2

500

5.882

2.51E-01

1.70E-02

1.05E-14

6.70

15.0

0.68 ± 0.05

3

550

2.023

3.02E-01

6.41E-03

8.67E-15

10.1

7.10

0.11 ± 0.06

4

600

2.551

8.65E-01

6.59E-03

8.67E-15

13.5

25.5

0.50 ± 0.04

5

650

2.094

4.77E-01

6.17E-03

5.10E-15

15.5

14.1

0.23 ± 0.07

6

700

2.409

1.49E-01

6.16E-03

9.69E-15

19.3

24.7

0.46 ± 0.03

7

750

2.287

1.65E-01

5.45E-03

8.67E-15

22.7

29.8

0.53 ± 0.04

8

800

2.270

7.41E-02

4.32E-03

1.94E-14

30.3

43.8

0.77 ± 0.02

9

850

1.499

1.46E-01

1.45E-03

6.56E-14

56.0

71.8

0.83 ± 0.01

10

875

1.652

2.25E±00

1.54E-03

2.65E-14

66.4

80.6

1.03 ± 0.02

11

900

1.617

4.72E-01

1.42E-03

2.96E-14

78.0

75.7

0.94 ± 0.01

12

925

1.747

1.18E±00

1.75E-03

1.56E-14

84.1

74.3

1.00 ± 0.02

13

950

1.796

1.22E±00

2.00E-03

1.17E-14

88.7

71.0

0.98 ± 0.03

14

975

1.804

1.62E±00

1.99E-03

9.95E-15

92.6

72.6

1.01 ± 0.03

15

1000

1.922

2.67E±00

2.47E-03

6.38E-15

95.1

70.2

1.04 ± 0.05

16

1050

1.881

4.33E±00

2.47E-03

6.12E-15

97.5

74.9

1.09 ± 0.05

17

1100

2.076

7.13E-01

2.46E-03

2.04E-15

98.3

66.8

1.07 ± 0.15

18

1400

3.478

3.22E-01

7.26E-03

4.59E-15

100

38.8

1.04 ± 0.07