Posted on

Observations for 2021 August 31


Busy morning. First I had to go down to check on Fan & Mortar since there had been no reports of any activity or status since sunset yesterday. (Some people can't be bothered to report the obvious while on their way to look at "the sun dress.") From Culvert I could already see that the bridge was wet. The wash zone extended all the way beyond Spiteful and Norris Pool. The vents were completely quiet, so it had been several hours, but it also hadn't been before midnight.

From there, did a quick check on East Sentinel and discovered it too had erupted, and recently. The water in the vent was down about 1/2 meter and calm and clear. The large catch basin was still steaming gently. It looked like the grass to the south was pushed down more. If not a major eruption, it was a pretty powerful minor.

On the way back, as I was rounding the curve below Oblong, a bison started to step out of the trees as I rode past. I was gone before either of us could react.

While tying up my bike, I saw that Bulger was in a strong, major eruption. As I walked down that way, I saw Bulger's Hole start up, too. Height was at least a meter above the rim, and lasted for well over 1/2 minute.

Finally got out to Grand, which was my intention when I got up this morning. Had just set the pack down and wiped down the bench when I saw a large boop from Grand. A couple seconds later the eruption had started. Was another One Burst Grand, but there was just enough breeze that the water jets were visible from West Triplet area.

With nothing much going on, it was a good time to visit Lone Star. We arrived just as the eruption was making the transition from water to steam, probably the time with the longest wait for the next eruption. Decided that we'd rather not kill a few hours there, and returned.

When walking out to the noontime Grand, I noticed a jet of water coming from Penta. Sawmill was in eruption, and Penta was having a weak steam-phase eruption. There were a few more jets of water from the Top Vent, and a lot of noise from the vents, but there had been no water discharge. The Sawmill Group was in a deep drain, with Spasmodic's water levels almost out of sight.

The wait for Grand was a long series of non-descript Turban eruptions and intervals. As the seven hour mark was passed, we had short Turban interval of just under 16 minutes with a short Turban duration. I was wondering if we were going to get a repeat of the other night, but it turns out we got a One Burst Grand eruption with the next Turban eruption start.

By then it had gotten very windy. Stopped by Daisy at the 2-1/2 hour mark, and decided instead to check out East Sentinel. It had recovered from this morning's activity, with the vent discharging water. All the activity was back along the northern rim, with some of the boiling going well over the rim itself.

Returned to Daisy, and it still hadn't erupted. Ended up being an interval well over three hours long.

Finally went out to Grand after sunset. Never saw a Turban eruption, but did wait close to half an hour. It was one of those time when once Turban started, there seemed little doubt that there would be another One Burst Eruption. The only interesting part of the eruption was during the wait, when a bison went through the Sawmill group on its way to the river.