| Date: | 2021-12-14 |
| Time: | 0718 E |
| Geyser: | Castle |
| Webcam: | No |
| Initial: | No |
| Major/Minor: | Major |
| Duration: | |
| Time Entered: | 2021-12-15 08:49:36 |
| Time Updated: | 2021-12-16 14:00:46 |
| Time Uploaded: | 2021-12-16 14:00:47 |
| Entrant: | aferrara |
| Observer: | |
| Submitted to: | GeyserTimes for Android |
| Comments: | ~10min spike on logger. Ambiguous logger reading, following eruptions indicate this was a major. |