[Geysers] Shoshone Geyser Basin, 05 July

[jacross]

I visited Shoshone Geyser Basin on 05 July.  Findings are as follows:

I saw two eruptions of Frill Spring.  For at least 23 minutes prior to the 
first eruption, the pool was heavily agitated and the pool burst to 1-3 feet, 
gathering strength as the eruption approached.  The little drinking fountain 
vent next to the crater was in a powerful steam/spray eruption to 4 feet, 
while the little hole next to it sputtered.

After the first eruption, water drained several feet down in the crater.  It 
slowly rose, boiling violently.  When it reached overflow 18 minutes later, 
the second eruption occurred.  It was about 20-25 feet high.

After the second eruption, events proceeded as before, but when the third 
eruption seemed imminent, 22 minutes later, the boiling suddenly stopped and 
the crater went completely quiet.  The water drained down 2.5 feet.  Over the 
next few hours it rose slowly, with at least one powerful roiling overflow but 
no further eruptions.

Typically Frill Spring erupts in series every 5 days, with series lasting 
around 8 hours and around 15-20 minutes between individual eruptions.  This 
activity was distinctly different.  It probably represents an aborted series.

Bead Geyser was nicely active, with intervals of 70-100 minutes and durations 
of just under 2 minutes.

Double Geyser was active, with two intervals of ~60 and 80 minutes.

Other geysers seen active were: Trailside, Soap Kettle, Little Bulger's side 
vent, Minute Man, Minute Man's Pool (minors to 4 feet), Gourd and Shield, Iron 
Conch, Mangled Crater, Knobby, and an unnamed geyser south of Flake Spring.

The Hydra is almost certainly active (fresh wash) but was not seen.

Meander Geyser was dormant.  I have not seen it erupt for a few years now.

Union Geyser and all vents to the east were drained to alarming depths.  The 
water level in Union is at around -6 feet in the main cone, -4 feet in the 
north cone.  Sea Green pool is at -4 feet and was actually periodic (though I 
do not regard this as a positive sign).

Vents north and west of Union were active at fair levels, with flow from one 
ponding on the trail.

Slosh Geyser is probably dormant (no recent wash), though it is hot, clear, 
and splashed a little during long pauses in Knobby's activity.

Lion Geyser may have been active but was not seen.

Jeff Cross
jacross at lamar.colostate.edu