[Geysers] Activity of Spectacle in 1975

[Lynn Stephens]

THIS POST IS FOR THE PERSONAL USE OF THE READERS OF THIS LISTSERV AND IS NOT TO BE USED FOR ANY OTHER PURPOSE,INCLUDING PUBLICATION IN THE SPUT OR TRANSACTIONS. Will Boekel is transferring data from the electronic versions of the OFVC logbooks posted on GOSA's website (geyserstudy.com) to Jake Young's geysertimes.org website.  He is in the process of transcribing the 1975 logbook.  A question about Spectacle Geyser came up recently.  Here's what Rick Hutchinson said about Spectacle in his 1975 report: 

Round
Geyser – Spectacle Geyser – Abuse Spring:  These three
features have exhibited intensified activity but also much greater irregularity
over last year.  Many long frustrating
hours were spent by Marie [Wolf], Sam [Martinez], James [no James listed in Rick's list of acknowledgements; possibly Jim Lenertz, or possibly Jamie Espy?], and me in an attempt to understand the
on-going changes and to determine the average intervals.  For a detailed discussion for this group of
features it is highly recommended that Sam Martinez’s reports for June and July
be read.

            The two key observations that were
produced by our work was, 1) that erosion was significant, and 2) that the
increased activity was associated with a new type of eruption from Round.  Erosion of the sinter was very noticeable
around all three:  the laminar sheets of
the west side of round Geyser’s cone was breaking up by frost and water action
while Abuse was ejecting a wide assortment of rocks and small trash, eruptions
from Spectacle in May and the first half of the summer season were very
destructive to the geyser’s vent.  Sinter
slabs in and around the vent were dislodged, shattered, and abraided [sic] into
small pieces; thus in the process enlarging it a great deal.  In 1974, a porous block of sinter over 16
inches long was cast out and by the end of July, 1975 a large 5 inch thick
sinter slab in the middle of the vent was broken into several pieces.  In September of last year, Round began to
have an occasional eruption from an empty crater around 2 to 4 hours after a
regular full eruption.  These became
common this year an[d] were aptly named by Sam Martinez as “dry
eruptions”.  The “dry eruption”
contributed to the irregularity and with the extra expenditure of energy,
lengthened the intervals between the regular eruptions. Here's what Sam wrote in his July 1975 report: Spectacle Geyser:  Behvaior continued to be irregular and increasingly violent in July.  Although eruptions were not frequent, they were very powerful compared to those in 1974.  By July 31 the large slab of sinter in the center of the crater, which had been about 2 1/2 feet square and five inches thick, had broken up into e or 4 smaller pieces. These pieces were juggled about and throws [sic] further from the vent.     The discharge from each eruption was very much the same as during June but seemed to be expelled faster.  The level after the eruptoin was a few inches below the openning [sic] in the chamber under the surface deposits.  usually a few seconds after the eruption ended there was a period of spraying from under the deposits caused by large bubbles breaking the surface of the water under the ledges around the vent. That's is for historical information for awhile.  I'm leaving for 2-3 weeks in Yellowstone and won't have daily internet access. Lynn Stephens 

 

 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: </geyser-list/attachments/20120626/1ab0f714/attachment.html>