[Geysers] Potts Basin

[Ralph Taylor]

Carolyn Loren wrote:


Yesterday, 7/23, a large feature near the lakeshore erupted to Oblong size
(but light muddy) each 7-12 minutes with several big bursts each time:  at
1102, 1109, 1110-11, (missed a probable 1120 but saw residual steam), 1131
weak, 1132 strong again, 1141 weak, 1144 strong.  The latter were seen
closer (I was paddling) so perhaps all big bursts were preceded by smaller
boils.
 
>From the fence near the road, the feature is in line and beyond the series
of green pools; only a smaller amount of boiling was seen from there between
1408 and 1430 (but when I was on the lake a number of people were watching
from the fence when I arrived, and stayed a while, so perhaps the display
started a good while before I was in sight).  From the lake, the feature's
location is between a small perpetual spouter a few feet from shore and two
substantial runoff channels that enter the lake and have yellow-green
thermophiles in them. 

Jim Holstein also reported eruptions about a week ago.  I investigated the
area and concluded that the feature that erupted then (and from Carolyn's
description, seems to be still active) is an established hot spring in the
middle of the old roadbed (!).  It is #17 on our maps of the Potts area, and
had no previous known eruptive history.  There are two well-sintered runoff
channels from #17 to the lake, but when I investigated Jim Holstein's
report, there were two additional new channels washed in the gravel and
substantial additional erosion around the sintered channels.  Some rocks and
gravel were also scattered about.
 
In the ten years that Bronco and I have studied the area there have been
numerous instances of springs activating for one season, sometimes for only
a few eruptions.  The lake level is quite low for this time of year, about
what we would normally expect in late August.  We frequently see features
heat up and sometimes erupt in August as the lake level drops.
 
I deployed a logger on #17 on 16 July (the day following Jim Holstein's
report) and downloaded it on 19 July.  On the 19th I saw no sign of an
eruption, and the logger showed no sign either.  It will be very interesting
to see the logger trace (assuming it survived!) of the time at which Carolyn
saw the eruptions.  
 
I am out of the park until 4 August, and will not be able to get to Potts
Hot Spring Basin for a few days after that.
 
Ralph Taylor
 
 
 
 
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