Table 1.
Overview of radiokrypton samples
| Sample | Stratigraphic age (ka B.P.) | 81Kr (pMKr) | 81Kr age* (ka B.P.) | 85Kr (dpm mL−1) | 39Ar (pMAr) | δ86Kr/4 (‰) | Air content (mL kg−1) | CH4 (ppb) | δ18Oatm (‰) |
| Kr-1 | 12.2 ± 0.5 | 101 ± 7 | 3 ± 23 | <0.99 | 28 ± 13 | 3.51 | 110.8 | 477.8 | — |
| 97 ± 7 | <1.15 | ||||||||
| Kr-2 | 49 ± 3.6 | 94 ± 6 | 46 ± 21 | <0.89 | <15 | 2.26 | 104.4 | 521.6 | 0.286 |
| 80 ± 5 | <1.10 | ||||||||
| Kr-3 | 123.5 ± 4.2 | 73 ± 6 | 120 ± 26 | <0.82 | <30 | — | 107.0 | 604.3 | −0.390 |
| 66 ± 5 | <1.31 | ||||||||
| Kr-4 | 79 ± 4.5 | 76 ± 5 | 86 ± 24 | <0.74 | <15 | 2.41 | 104.3 | 484.8 | −0.065 |
| 78 ± 6 | <1.33 | ||||||||
| Atm | 0 | 107 ± 7 | −7 ± 23 | 72.1 ± 3.8 | — | 2.38 | — | 1755.0 | — |
| 97 ± 7 | 70.9 ± 3.7 |
*
Duplicate 81Kr analyses are averaged to calculate the listed 81Kr radiometric ages. pMAr, percent Modern Ar; ppb, parts per billion.