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Observations for 2020 September 04

Decided that there wasn't much point to getting out to Grand as it was getting light, so surprised to find out that it had a well over seven hour interval. That messed up plans for the morning, so didn't really get out til it was close to noon. Mostly got started because there was some minor event at Fan & Mortar, and wanted to see what was going on, but arrived after everything died down.

As it was, Castle started erupting as I was tying down my bike. It had all the earmarks of being a minor eruption, as it was constantly stopping and suddenly restarting. One pause, around the 4-1/2 minute mark lasted for almost a minute. But by 15 minutes it was obvious that the transition to steam had started.

Over at Grand, it was a short, two Turban interval wait with no sign of any delays. The eruption itself as two bursts, which is always welcome.

From there, wandered back down to Fan & Mortar to kill some time. Nothing much happened. On the way back, noticed that Spa was boiling in the northern vent, and near overflow, waited for a bit, and it finally did get to overflow. But within ten minutes, the boiling had quit, and it was back below overflow. Grotto was quiet during all this.

Went out for the afternoon Beehive (they are all afternoon Beehives). From there it was obvious that the fire to the south had flared up, and was getting bigger as we watched. No smell of smoke yet, but expect that to change tonight. Last night we caught whiffs of smoke while waiting for Castle.

The evening Grand was entertaining in multiple ways. I saw Turban in eruption as I was walking up, and when I arrived, West Triplet was in overflow, ending about a minute later. The next interval turned into a Turban Delay,

At around the 28 minute mark, Grand, which had been having waves, booped. Then over the next minute, it had several more, before starting to drop. Turban finally erupted about 6 minutes later, and Grand was low. I made a few notes about the activity, taking about a minute, and when I looked up, Grand was not only full again but having another boil. That lead into an explosive start for Grand.

With the sun low, there were some nice rainbows. And it was a pleasant surprise when Grand quit at the 8m24s mark. Except it really didn't try to refill, and then drained, making this one of the shorter eruptions I've seen.

We waited a bit for a possible afterburst, but Grand gave no sign of that happening. So it was about seven minutes before I got down to WestTriplet. It was in a heavy overflow, with thumping and large waves being generated over the vent. Also, a brochure which had been sitting in the vent area for several days finally started to fall apart, with lots of shreds being circulated by the convecting. None of them were escaping down the runoff.

Over the next six minutes, the thumping and upwelling got stronger, and we started getting small splashes. These quickly built into splashes that I consider to be eruptive activity. Then about three minutes later the splashing got really strong, and continuous, and it was obvious that West Triplet was in a full eruption, the first since 26 Aug. During all this, the remainder of the brochure finally drifted into the vent, and it became part of the shreds being circulated.

It was only three minutes later that Rift started. This seemed to start out slower that the typical Rift eruption, and I wouldn't have been surprised if it had been one of those rare eruptions that never overflow. But it too got stronger as the eruption progressed, and the runoff looked normal.

I've seen Grand have this sort of "low pool eruption" before, but this is the first time I can remember actually seeing West Triplet come out of a dormancy period. Interesting that the eruption started in a way (very gradually) that is much different from normal, and how Rift came alive so much faster than normal.

Went out before midnight for another Grand eruption. The smoke filled the basin, not quite as bad as some of the geyser fogs, but still not pretty. While waiting for Grand, at one point Rift started steaming heavily, and making rumbling noises at depth. This lasted for about four minutes, at a time when Sput D was active. An interesting followup to the earlier eruption.

This Grand eruption had a first burst that lasted 7-1/2 minutes, and the whole eruption was only 9m06s. The second time in a row that we were cheated out of a burst.

Also, the bison have made their reappearance, choosing to use the roads to move around, causing lots of problems.