[Geysers] Trip Summary, July 20-25 (fwd)

[Michael Goldberg]

I was more a tourist than observer on this trip, but there don't seem to 
be all that many reports coming out of the park lately.

Plume: 50-ish minute intervals whenever I was paying attention. 
Eruptions started from an empty crater, preceded by 3-5 minutes of audible 
boiling at depth.  [Note: Plume hasn't been reported since 0659 on
August 2.]

Beehive: 12-17 hour intervals, with mostly 15-20 minute Indicator.
[Note: Beehive has since had a couple of shorter intervals, at least one 
of which featured a mid-cycle indicator.]

Lion: Series of a half-dozen eruptions were more frequent than once per 
day. This being Lion, wide variations around the average are typical.
I didn't watch North Goggles but series of minor eruptions were reported.

Giantess apparently got a lot of people's attention with frequent vigorous 
boiling the morning of July 18.  Then it settled back down to its usual 
sporadic boiling and has not erupted.

Castle: Predictable except for the couple of days it had minor eruptions 
in the morning.

Sawmill Group: mostly in Sawmill mode except for the afternoon/evening of 
July 24.  On one cycle Penta looked promising for a late-cycle eruption 
(following waves on Oval) but everything quit and drained before it got 
the chance.  Penta did erupt the next cycle, then Sawmill took over again.

Weak Penta steam phase eruptions were seen a few times on other days.

Bulger had major eruptions with no observed response from Bulger's Hole.

Grand: Most intervals stayed on the remarkably short end, including one 
that was 5 hours 42 minutes.  But if it didn't go on the early side, it 
could be a long wait.  I think the prediction window (5.5-9.5 hours) got 
used to its full extent.

The eruption capping the shortest interval was unusual in that Vent waited 
over 8 minutes to join in, so it was at full strength near the end of 
Grand's first (and only) burst.

One time I saw a small pool splashing out in the flats below Grand, just a 
bit left of Vent's runoff channel.  Every other time I looked out there, 
the vent was empty and difficult to locate.

Oblong: Intervals of 3.5-6.5 hours whenever I was paying attention.

Daisy: Intervals near 2.5 hours whenever I was paying attention.

Grotto Complex: At least two marathon eruptions, one of which lasted 22-23 
hours and featured impressive activity from Spa.  Rocket majors were 
reported; I didn't catch where there occurred within Grotto's eruptions.

Riverside: Short intervals were 5:3x and long intervals were 6:0x.

Fan and Mortar: A strong Gold Pause event cycle near the 4-day point in 
its interval.  After that it had generally so-so events every 6-12 hours 
for the next couple of days until a very determined event cycle led to the 
July 25, 1131 eruption.

Artemisia: Intervals of 12-20 hours whenever I was paying attention.
Atomizer: I saw a "comeback" major, but aside from that 13-minute 
interval I have no context about its current behavior.

Cauliflower: I caught a 3-ft eruption in the afternoon July 23, and 
another eruption that just roiled the pool surface.

Lone Star: On July 21 I saw:
13:30 arrived.
13:58 major eruption
16:10 minor eruption (d=2min)
16:34 minor eruption (d=5min)
17:15 major eruption

I find the different modes of preplay quite interesting.  Sometimes the 
main vent splashes heavily.  Other times (especially after a minor 
eruption, I think) only the little vents sputter and the main vent is 
quiet until the very last moment.

Michael Goldberg
Michael.Goldberg at uc.edu