<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv=Content-Type content="text/html; charset=us-ascii"> <meta name=Generator content="Microsoft Word 11 (filtered medium)"> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place"/>  <style>  </style> </head> <body lang=EN-US link=blue vlink=purple id="role_body" bottomMargin=7 leftmargin=7 topmargin=7 rightMargin=7> <div class=Section1> Linda and I spent the last week in <st1:place w:st="on">Yellowstone</st1:place>, and I want to fill you in on some geyser activity.<o:p></o:p> <o:p> </o:p> 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.  <o:p></o:p> <o:p> </o:p> 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.<o:p></o:p> <o:p> </o:p> 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 <st1:place w:st="on">Marathon</st1:place> 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 <st1:place w:st="on">Marathon</st1:place>.  But no, it quit at 1243.  I’m not too familiar with 3 hour recovery eruptions of Grotto.<o:p></o:p> <o:p> </o:p> 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.  <o:p></o:p> <o:p> </o:p> 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.<o:p></o:p> <o:p> </o:p> 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”.)<o:p></o:p> <o:p> </o:p> 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.<o:p></o:p> <o:p> </o:p> 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).<o:p></o:p> <o:p> </o:p> 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.<o:p></o:p> <o:p> </o:p> 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.  <o:p></o:p> <o:p> </o:p> 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.  <o:p></o:p> <o:p> </o:p> 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.<o:p></o:p> <o:p> </o:p> Paul Strasser<o:p></o:p> <o:p> </o:p> <div> <div class=MsoNormal align=center style='text-align:center'> <hr size=2 width="100%" align=center tabindex=-1> </div> From: geysers-bounces@wwc.edu [mailto:geysers-bounces@wwc.edu] On Behalf Of TSBryan@aol.com Sent: Friday, June 24, 2005 7:43 PM To: geysers@wwc.edu Subject: Re: [Geysers] Geyser report Wednesday June 22<o:p></o:p> </div> <o:p> </o:p> <div> <div> In a message dated 6/23/2005 8:29:56 PM Mountain Standard Time, siegmund@mosquitonet.com writes:<o:p></o:p> </div> <blockquote style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt; margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'> 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.<o:p></o:p> </blockquote> </div> <div> 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.<o:p></o:p> </div> <div>  <o:p></o:p> </div> <div> Scott<o:p></o:p> </div> </div> </body> </html>