[Geysers] Fascinating Vixen

[M.A. Bellingham]

Hello Gazers -

Late last fall I couldn't make sense of the Vixen intervals just
before road closing, which continued through this spring.  I set out
to learn what I could to maximize my time there, and learn the
pre-eruptive behavior so I wouldn't have to wait around for 90 minutes
(like waiting for Vixen prior to Oct. 2013… first gurgle is X minutes
until eruption, and so on).

What I found was a very interesting pattern, which is still
continuing, with some variants, as of July 4th.

As far as I know, Vixen has not had cyclic behavior since 1984
(Paperiello, “Report on the Norris Geyser Basin for 1984”).  It might
have happened - - infrequent reports calling it “erratic” might be due
to limited observations and not seeing the 'big picture'.  We may
never know; for example, a mention in 1927 states "some days quite
dormant and others a spurting spit-fire." (I am going to continue
looking at historic accounts with a new eye and see what I can find.)
I myself have been guilty of only staying for a few hours and then
leaving for Whirligig, but generally the behavior and intervals would
remain consistent from week to week. Although Norris features change,
once you figured it out, it was good for a while, so I do not think it
has done this in the last two decades.   If you know otherwise, I
would be happy to be wrong and have more information!

This activity "basically" includes a rest period as the pool slowly
fills from low in the tube, followed by an eruption from a very very
full platform. The longest rest-refill period in these last 2 weeks
was about one hour (shorter than it was earlier in the season). This
is followed by a group of "medium" intervals, say 20-30 minutes,
shortening as we go along to, for example, 15, 12, 10, 8 minute
intervals.  At some point the bubbles indicating a pending eruption
begin ASAP after the end of the previous and game on!  Short intervals
continue for quite a while, about 2-5 minutes apart, depending on
duration. Some brief duration eruptions are in the same minute, others
are of longer duration, but the similarity is that the restart action
begins quickly after the end of the previous.  All this time the pool
is slowly lowering and the eruptions do not start from the full
platform.

In discussion with several gazers who have sat through this
cycle with me, we haven't yet agreed on which is the start and which
is the end of the cycle.  That's a discussion about geyser series
behavior that we can hash out… when the roads close!!
At this point I have seen about 1200 eruptions this season, around 20
visits, with many “closed” sets.  Statistically, I know that isn't
huge, but it's definitely fun once you understand the pattern.

Stop in and see it!!  If you want to be helpful, getting data on the
LONG intervals is, to me, more important than enjoying the frequent
eruptions, but when those kick in, it is the fun reward for staying!
Closed intervals are great, of course, but if you see just one (or
none), a comment about the length of time it was NOT in eruption and
the pool level on the platform while you were there would also
be helpful.  During past eruption-behavior changes, good observations
on GeyserTimes have really helped narrow down the day (or in one case,
half a day) of when dramatic changes occurred, even if the observer
didn't stay long.

Help if you can, it's for the historic record.  Thanks.
And PS!  If you want to see this, I'd get down there, you never know how long it
will last!   It is Norris, after all.

MA

M.A. Bellingham
mabellingham at gmail.com