(light upbeat music)
Hi everybody, I'm Mike Poland,
Scientist-in-Charge of the Yellowstone Volcano Observatory
and I'm here today at Steamboat Geyser
in Yellowstone National Park
on a chilly, late spring morning.
Steamboat is the one that's been going off
about once a week or so over the last year plus.
They're really spectacular eruptions.
It just erupted the other day,
so we're seeing the steam phase now.
We're here in the park doing some field work,
our early summer work,
that includes deploying a number of GPS stations
in various places throughout the park,
and also repairing and doing maintenance
on the temperature network in the Norris area.
And you can read about this kind of work
in the May 27th edition of Yellowstone Caldera Chronicles,
on the YVO website.
And I'm happy to report that we've got
the whole Norris temperature network working again,
including the Steamboat logger,
which hadn't been working since late fall
last year due to a malfunction.
So, the Norris temperature network is running,
you can detect now, Steamboat eruptions
by going to the monitoring map on the YVO page.
So, with all of that out of the way,
let's get to the May update for what's happened
over the last month in Yellowstone.
The University of Utah,
which is responsible for the operation and maintenance
to the Yellowstone seismic network,
located 77 earthquakes during the month of May
in the Yellowstone region.
You can see that here, most of them occurred in this band
that's sort of at the East of Hebgen Lake.
This is sort of the hotbed seismicity
in the Yellowstone region.
You might remember, this is where the Maple Creek
earthquake swarm of 2017 and 2018 occurred.
But overall, the seismicity in the Yellowstone area
has been background for the month of May.
In terms of deformation, we're seeing
continued patterns of subsidence in the Caldera.
This is from the White Lake GPS station
over the last two years.
This is showing the vertical deformation.
And this overall downward trend,
is subsidence of the Caldera at a rate
of two or three centimeters per year or so.
The Old Faithful GPS site shows basically the same trend,
slightly less subsidence
and there's this little dip right here
in April, which may be a seasonal effect -
some late winter, early spring weather
affecting the Yellowstone region.
And finally, there's the Norris area,
which had been uplifting since 2015.
This is the last two years of deformation
in the vertical sense, in the Norris area.
And that'd been uplifting, except for this
little bit of subsidence here that occurred in late 2017.
But their uplift trend paused in October of 2018.
And since then, we haven't seen much deformation,
maybe even just a little bit of subsidence.
We'll have to keep our eye on this trend
and see how it evolves overtime.
Wanted to share a little bit of information
with you about Steamboat Geyser.
As you may have heard,
it's continuing its pattern of eruptions.
It actually erupted five times in the month of May,
on May third, May eighth, the 13th, the 20th, and the 27th.
We got the temperature loggers working again
during some May field work.
And this is the temperature record
for the May 20th eruption.
So, all of this variation leading up to the big eruption,
which is right there, is showing minor eruption activity.
So a lot of variations in temperature.
There's the big eruption,
and the temperature immediately drops.
There's a little bit of more minor activity
and then basically, Steamboat goes dry for a couple of days.
And what we're seeing here,
this very thin line without much variation,
is the daily temperature variation.
A couple days after the major eruption of the 20th,
the temperature started to pick up
and we're seeing more variability in that temperature
as minor eruptions begin again.
And you can see very quickly,
it gets back up to this 40 degree centigrade temperature
that it had before the last major eruption.
And this led right into the May 27th eruption.
So, neat temperature data coming from Steamboat
now that we've been able to fix those loggers,
as part of our late spring field work.
There is some neat stuff going on at Steamboat,
of course, and I wanted to show you
some of the pictures from our field work.
We didn't catch the May 20th eruption,
but we did catch the steam phase,
which was still very, very impressive.
This is just from two or three hours
after the major eruption of May 20th.
You can see just how forceful
the steam coming out of the vent is.
There's also a neat spring or pool
nearby Steamboat, called Cistern.
Cistern's wellknown for being very full
and overflowing prior to Steamboat eruptions,
but then just after Steamboat eruptions,
it drains, as you can see here.
This drainage picture was taken on May 21st,
just a day after the Steamboat eruption.
So clearly, there's a lot of connectivity
between some of these features in the Steamboat area.
Finally, just wanted to remind you,
all of this information is available on the YVO website.
We've redesigned it to include more of the volcanoes
in the YVO area of responsibility,
which includes the Four Corners region.
You can always find the monthly update right here
and if you scroll down, you can link directly
to Yellowstone and Caldera Chronicles.
And if you link to Yellowstone,
you'll be able to find our monitoring page
and all of the other information
you've come to expect from YVO.
Okay, thanks everybody.
Hope you have a great June and we'll see you in early July.
Take care.
(light upbeat music)