[Geysers] Question re "muddy" Steamboat

[Bill Johnson]

I'm relatively new here, and have experience of Steamboat only from seeing 
a bunch of minors (my first ones nearly 40 years ago when I was but a tad) 
and doing some reading, so my apologies if this has been covered 
previously, but:

In the recent photos of the major, it is quite obvious that the column from 
the (presumably) south vent is at least slightly muddy.  The Bruce Chase 
photos show not only a distinct color difference between the two columns, 
but also some really grungy brown stuff at the base of the right-hand 
column.  However, I have never seen anything in Scott Bryan's book or any 
other source alluding to muddy discharge during a major.  The classic 
photographs (like the one on the previous edition of TSB's book) don't show 
any discoloration to speak of, but of course that isn't definitive because 
of the way color balance is done.

Is this a known phenomenon?  Would value input from experienced Steamboat 
followers.

-- Bill Johnson
Los Alamos National Laboratory
(mwjohnson at lanl.gov)