| Eruption | Duration | Interval |
|---|---|---|
| 02 Oct 2018 @ 1025 ie | 16d 3h 16m | |
| 16 Sep 2018 @ 0709 | 6m | |
| 16 Sep 2018 @ 0703 ie | 104d 20h 10m | |
| 03 Jun 2018 @ 1053 ie | 42y 8d 14h 6m | |
| 04 Jun 1976 @ 2047 | 18d 6h 54m | |
| 17 May 1976 @ 1353 | 13d 18h 29m | |
| 03 May 1976 @ 1924 ie | 281d 23h 33m | |
| 26 Jul 1975 @ 1951 | 100d 9h 26m | |
| 17 Apr 1975 @ 1025 | 7m | |
| 17 Apr 1975 @ 1018 | 8m | |
| 17 Apr 1975 @ 1010 | 9m | |
| 17 Apr 1975 @ 1001 | 8m | |
| 17 Apr 1975 @ 0953 | 9m | |
| 17 Apr 1975 @ 0944 | 9m | |
| 17 Apr 1975 @ 0935 | 9m | |
| 17 Apr 1975 @ 0926 | 7m | |
| 17 Apr 1975 @ 0919 | 1d 15h 32m | |
| 15 Apr 1975 @ 1747 | 31s | 9m |
| 15 Apr 1975 @ 1738 | 1d 6h 50m | |
| 14 Apr 1975 @ 1048 | stm12water23 | 8m |
| 14 Apr 1975 @ 1040 | 32s | 19h 29m |
| 13 Apr 1975 @ 1511 | stm15s/water17s | 9m |
| 13 Apr 1975 @ 1502 | stm13s/water23s |
| Interval Count | 22 |
| Min | 6m |
| Max | 42y 8d 14h 6m |
| Mean | 1y 356d 17h 14m |
| Median | 9m |
| Note ID | Start Time (US/Mountain) | End Time (US/Mountain) | Entrant | Note |
|---|---|---|---|---|
| 7599 | 13 Mar 1984 @ 1800 | --- | research-mab | 3-13-84 Additional observations on Geyser Hill: the funnel shaped vent of “Inverted Geyser” east of Arrowhead Spring can not be found. It seems highly probable that it may have been destroyed by a violent rupture of the sinter sheet around 1m in diameter. Accurate measurements & a review of records on Inverted will be made later to test this theory. |