| Clue | Source | Date |
|---|---|---|
| Related to a branch of science | ||
| Earth-related | Wall Street Journal | 02 Jun 2023 |
| Re earth science | Eugene Sheffer | 13 Aug 2018 |
| Of a certain earth science | ||
| Like some historical time scales | ||
| Like some historical time scales | ||
| Kind of time | ||
| Certain time |