[Geysers] Some info from the upper basin

[Paul Strasser]

Linda and I spent the last week in Yellowstone, and I want to fill you in on
some geyser activity.

 

First, two gazers (Karl Hoppe and Dave Leeking) independently went up to
Norris to check on Steamboat's recovery from the 5/23 eruption.  Both
reported that Steamboat was having minor activity, primarily south vent
(with some vertical jetting) and a little under half of minors were
concerted.  No great claims of impending majors can come from this, but
prior to their observations the only 3rd-hand info I got was that about ten
days earlier there was no minor activity at all.  If I was in the park, I'd
probably check it out every week or so (or try and convince someone ELSE to
check it out.) It has recovered to the point where modest yet decent minor
activity is occurring, suffice to say.  

 

Grand changed abruptly on 6/21.  The T4Q that occurred at 2257 was not an
outlier, but seemed to indicate that something different was up.  All
eruptions I'd seen (or had been recorded) since I arrived were one bursts.
After the four-burst eruption, there were no one-bursts seen at all.  The
durations were also longer (12m09s, 11m14s,12m42s,appox 13 min 10s, and
finally a 9m55s) than seen before.   A few intervals (in mid-day, of course)
were longer - one because of a D9 on 6/23 and a Rift-assisted 8h45m on the
24th.  There is no way of knowing if this trend will continue, but I'd
prefer 8-hour multi-burst intervals rather than 6h30m intervals with only
one-bursters.

 

Giant and Grotto were, um, interesting.  When I arrived Grotto was in the
midst of a long period (15 eruptions!) between marathons.  It then had a 21
hour marathon followed by a very short recovery eruption that quit appox
0610 (we were at Giant; this time is +/- 10 minutes).  At 0820 a Marathon
started, which ended sometime before 0018 on the 24th.  Grotto's recovery
eruption started at 0945, and as its duration reached the 2h45m mark we
thought it might be another Marathon.  But no, it quit at 1243.  I'm not too
familiar with 3 hour recovery eruptions of Grotto.

 

Giant's hot periods were very frequent, usually every 82-120 minutes.
Typically, there were two or three "lousy" hot periods (durations of 1m40s
to 4.5 minutes) followed by a longer, more powerful one.  However, this was
somewhat misleading.  The "powerful" hot periods may have been long in
duration, sometimes over ten minutes (typically 8-9), but for most of this
time Mastiff was MIFBOF (stupid anagram meaning "Mastiff Is Flat But
OverFlowing")  In nearly all these long hot periods, the time when Mastiff
was boiling to 1-3 feet lasted about four minutes - regardless of the total
hot period length.  

 

There were only two hot periods that truly got my attention.  One was the
"almost eruption" noted by Scott earlier this week that had a duration of 15
m 10s.  This was a very strong hot period, with Turtle to two feet, Cave to
2-3 feet, and very strong surging in Giant.  (The duration was the total
time Feather was on before it stopped - after Mastiff dropped there was no
pause in Feather; however, Feather's Satellite did stop for about five
seconds before continuing to play).  This hot period took place 4h 38m after
the 21-hour marathon.

 

The other hot period of note was 40 minutes after the end of the 12th
non-marathon Grotto.  Its duration of exactly 8 minutes wasn't unusual.  But
Mastiff surged 2-3 feet for about 7m30s.  This was far more Mastiff activity
seen in any other hot period (other than the "almost eruption".)

 

Other than those two hot periods, Giant seemed to have little inclination to
change its mode of behavior seen in the last few months.  The long hot
periods are sometimes quite benign in nature- Linda called them "extended
3-minute hot periods" to give you an idea of their look&feel.  To me, the
most interesting change is the amount of discharge from Turtle.  It
overflows and/or boils heavily on almost every hot period, and along with
the greater activity in Cave (and less exciting activity in Mastiff)
indicates that the energy on the platform is a bit on the south side.
Perhaps we should call Turtle "Giant's Thief." Or not.

 

One final note re Giant. The 3-hour recovery Grotto eruption seemed to
affect the Giant platform almost as much as a marathon.  It was quite dead,
even though hot periods took place 1 hr 5 m and 4 hr 20 minutes after the
end of this odd Grotto eruption.  (this was one of the rare times that the
interval between events on the platform was well over 2 hours).

 

A few other matters.  Great Fountain had one of the measliest eruptions I've
ever seen on 6/20.  With a near-full moon and ideal viewing conditions we
were anticipating a great show.  At 2250 it started.  It may have hit 30
feet, but that would be generous.  It was so awful that we were all laughing
at the sheer awfulness of the display.  Moral:  you don't need great
eruptions for great memories.

 

Slightly more sobering note.  The lightning storm on 6/21 was the most
intense I've seen at OF in 30 years.  Many gazers watched it coming, with
dazzling lightning forks approaching from the southwest for about 20
minutes.  When the strokes got within about 4 miles (and a smell of ozone in
the air) many of us moved from our vehicles (where we were watching the
show) to the Ham's store.  Several gazers down basin took shelter in the
POES (pit of eternal stench, AKA the Outhouse).  The point of the above is
to illustrate that it was obvious that a storm was coming.  Unlike a
rainstorm a few evenings later that basically came out of nowhere, this one
gave many minutes warning that something serious was coming.  When it hit,
it was like the developed area to Castle was ground zero.  There was
sometimes zero delay between lightning and thunder (sometimes the thunder
started before the bolt was finished with its flickering business).  We saw
several hit at or near Castle, one that might have even struck the Ham's
store, many behind us, many in front of us, several overhead, and one very
large one that illuminated the entire area and struck near the OF benches.
Within five seconds of this strike, three Protectives who were eating at the
Ham's Fountain ran to their cars, turned on their sirens, and drove at very
high speeds up the bikepath.  This was the strike that hit the visitors
waiting at the benches.  

 

Although I have enormous sympathy for the injuries sustained (the last I
heard about the boy most seriously hurt was "cautious optimism") I do wonder
what else would have motivated them to walk to the VC.  

 

Congrats, of course, to Mike and Cynthia.  Those who have been through this
can understand how someone can simultaneously look so completely happy yet
completely exhausted.  It does get better.  Really.

 

Paul Strasser

 

  _____  

From: geysers-bounces at wwc.edu [mailto:geysers-bounces at wwc.edu] On Behalf Of
TSBryan at aol.com
Sent: Friday, June 24, 2005 7:43 PM
To: geysers at wwc.edu
Subject: Re: [Geysers] Geyser report Wednesday June 22

 

In a message dated 6/23/2005 8:29:56 PM Mountain Standard Time,
siegmund at mosquitonet.com writes:

Could you tell us when these were in relation to each other? I can think
of a few theories current in the late 80s and early 90s that would love
for this hot period to have happened early in the 2h59m Daisy interval.

Sorry -- the Daisy interval of 2h 59m was between 0800 and 1159, and the
long hot period started at 1423 -- which happened to be 7 minutes after the
Daisy of the shorter interval.

 

Scott

-------------- next part --------------
An HTML attachment was scrubbed...
URL: </geyser-list/attachments/20050625/14ef953a/attachment.html>