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Observations for 2019 September 03

So the second geyser of the day I see in eruption is Churn, from over by the bike rack at Castle. It was a normal eruption, lasting about a minute and about 2-3 meters high. I was over at Grand twenty minutes later when there was a second eruption, just like the first, except maybe even taller. Or it maybe the first looked shorter because I was farther away.

The first geyser I saw erupting was Rift. It continued for several more hours, and during that time there were frequent small, short eruptions by Sput D. Sput F2 was steaming heavily, but I didn't see any indication of steam from Sputnik. There was even a short low-pool eruption of Percolator.

Arrived at Grand Group with Turban in a delay that eventually lasted over 30 minutes. This was followed by a second Turban Delay, this one about 33 minutes long. In both cases the Turban eruption duration was long, 6-1/2 and then seven minutes. The following Turban eruptions were much shorter, with poor overflow and little sign that Grand was trying to erupt. Rift ended three Turban eruptions after that. Finally, six Turban eruptions later, we finally got our eruption, an interval of about 8h18m, which is probably the longest interval of the year.

This activity was reminiscent of activity that's been seen before, when Rift would matter. Grand would stall out until a couple of Turban intervals after Rift had quit. I haven't seen this sort of behavior for years. It will be interesting to see in what mode the group is in tomorrow. Will West Triplet be active, or just overflowing.

Came out again before sunset, and this time Grand was a bit more cooperative. The first Turban interval seen was another Delay, with Grand having a boop at the 35 minute mark. The lighting was from low, as the sun was near the ridge, which made it easy to see any variation in the pool. There were never any good waves, and immediately after the boop, the pool dropped and it took 4 more minutes before Turban finally erupted. This eruption lasted almost 7-1/2 minutes.

Twenty minutes later, overflow was poor but Grand's pool was high, and rising. Turban started, and Grand kept rising, and the overflow started. Over the next two minutes, the pool kept getting higher and the waves kept getting bigger, until it was pouring water off. I expected an explosive start, but it was a normal build up of boils into bursts and then a full eruption. Vent started only 1-1/2 minutes after Grand, and the whole eruption, like the one earlier, lasted less than ten minutes.