(gentle music)
Happy New Year, everybody.
I'm Mike Poland, the scientist-in-charge of the
Yellowstone Volcano Observatory
and this is the monthly update for January 1st of 2023.
Seems like a good opportunity to talk about
the kinds of things we observed in Yellowstone
over the course of the past year.
Now in terms of earthquake activity,
it was a pretty average year.
There were about 2,500 earthquakes that were located
in the region during 2022.
Now, over a third of those earthquakes were actually part
of a single long-lived swarm near Grizzly Lake.
That's between Norris Geyser Basin and Mammoth Hot Springs.
There were over a thousand earthquakes
that occurred as part of the swarm,
which started in late July
and extended all the way into the fall.
Now that sounds sort of unusual
but it's not out of the ordinary.
We see actually lots of earthquake swarms
that can last for months.
In fact, in 2017, there was an over three month long swarm
that had 2,400 earthquakes.
And this is not too surprising in the region
given all the faults in the area
and all the water that's moving around in the subsurface.
That's just a recipe for a small earthquakes.
There were a few magnitude threes,
but the vast majority were magnitudes two and below.
The largest earthquake of the year was a magnitude 4.2
and that occurred in the eastern part of the park
back in May, and actually felt by many, many of the people
that are in the Yellowstone region.
That was the largest earthquake since 2017
but we get a magnitude four every now and then
in the Yellowstone region.
Deformation-wise, in terms of how the ground is moving,
we saw a continuation of the sort of activity
that we've seen for the last several years.
The caldera region continued to slowly subside
by about an inch or so per year,
couple of centimeters per year,
not much deformation in the Norris Area.
So it was really sort of a continuation
of the kinds of patterns we've seen for several years now.
Geyser activity, there wasn't a whole lot
of spectacular stuff that happened.
Steamboat Geyser, the tallest active geyser in the world,
erupted 11 times in 2022.
Now this may seem like a lot, but it's a far cry
from what we've seen in year's past.
In 2018, when Steamboat came alive, it had 32 eruptions.
There were 48 each in 2019 and 2020
and there were 20 eruptions in 2021.
So Steamboat may be on the decline right now
but hopefully it's not done giving us a show quite yet.
It was also a good year for field work.
The Yellowstone Volcano Observatory consortium,
all of the scientists from different agencies
that contribute to research in Yellowstone,
got together for the first time in four years in May.
In fact, the morning of that earthquake
that occurred back in May,
the 4.2 in the eastern side of the park.
We talked about the kinds of science
and new insights that have been enabled
by all the research that's been happening in Yellowstone
over the past several years.
There's also been a number of new scientific experiments.
For example, a new continuous gas sensor was installed
near the Mud Volcano area in this past year.
There was lots of water sampling and gas sampling as well
and maintenance of seismic sites,
deployment of new GPS sites.
All of that sort of information will be published
as results become available.
Now being the first of the year,
it's also a time for resolutions, right?
So what might why YVO be resolving to do in the coming year?
Well that's actually detailed in a report
that just came out this past year.
This is the monitoring plan
of the Yellowstone Volcano Observatory
for how we want to better understand what's happening
in the vicinity of Yellowstone National Park.
We talk about the different kinds
of monitoring tools we'd like to install,
the different kinds of data we'd like to collect.
In the coming year,
our hope is to install a new multi-component
monitoring station in Norris Geyser Basin.
Something that would measure earthquakes,
something that would measure ground deformation,
and also infrasound, that's low-frequency sound waves
so we can actually hear what the geyser sound like.
We'd also like to upgrade a lot of the seismic stations
that are in Yellowstone.
Some of them are getting a bit old
and we'd like to get them as modernized as possible
with new equipment.
So that's some of what we hope to do in Yellowstone.
If you're interested in hearing more,
our monitoring plan is available free online.
You can see what we'd like to do over the next decade
in terms of monitoring Yellowstone even better.
Well, that's sort of a quick review
of what's happened throughout 2022.
Now let's talk about specifically what happened in December
in terms of earthquake activity, ground deformation,
and geyser activity.
December was a pretty quiet month
for earthquakes in the Yellowstone region.
The University of Utah Seismograph Stations,
which monitors and operates the Yellowstone seismic network
located only about 70 earthquakes during the month.
The largest was a magnitude 2.5.
It was part of this Grizzly Lake sequence
between Norris Geyser Basin and Mammoth Hot Springs.
Now this sequence actually started back in the summer
and it's a swarm that's been waxing and waning
for many, many months.
There were about 28 earthquakes
during the month of December that contributed to this swarm.
But over the course of the year, there have been
over a thousand earthquakes that have occurred in this area.
The biggest month of this swarm was September
when there were over 500 events that occurred in this area.
Now this is part of a belt of seismicity that runs from
Hebgen Lake all the way into north central Yellowstone.
It's the most seismically active area in the region,
so it's not too much of a surprise
that there's a swarm occurring right here.
And in fact, just a few years ago in 2017,
the Maple Creek earthquake swarm occurred
not too far away right in this area here,
and that swarm saw over 2,400 earthquakes
that occurred over a several month period,
back in 2017.
So not too surprising.
We occasionally get these swarms
and many of them are right in this belt
between Hebgen Lake
and the north central part of Yellowstone.
Turning now to deformation,
this is vertical deformation, at the White Lake GPS station
on the east side of the caldera.
Each one of these blue dots is one day of data.
The whole plot spans two years.
Downward trends indicate subsidence
and upward trends indicate uplift.
And what we're seeing now is a continuation of trends
that have been ongoing since 2015.
That is of overall subsidence of about
two to three centimeters per year.
That's about an inch a year.
But during the summer months,
there are these periods where the subsidence stalls
or even turns to a bit of uplift.
You can see it here in the summer of 2021
and again in the summer of 2022.
And this occurs as groundwater is recharged by snow melt
and the ground sort of soaks it up
like a sponge getting wet
and it sort of puffs up the ground a little bit.
And then once we get into the fall, the subsidence resumed.
So you can see here in October,
the subsidence resumed out here at White Lake.
If we go to the other side of the caldera,
this is a site near Old Faithful
on the Mallard Lake resurgent dome.
The same trends are apparent.
This overall subsidence with the summertime uplift.
And you can see that was there in October
that the subsidence resumed after that summer 2022
pause in subsidence and a small amount of uplift.
Same thing true at Norris Geyser Basin as well.
There wasn't a whole lot of deformation overall at Norris.
A little bit of summertime uplift in 2021
then back to a bit of subsidence,
a little bit of summertime uplift in 2022,
and then back to a small amount of subsidence.
There are a couple of transients in here.
You can see this one in December, January of 2021, 2022,
and then here in November and a little bit in December.
This is caused by winter storms that put a lot of
snow and ice onto the antennas,
and that affects the GPS signal.
But once that snow and ice melts off the antenna,
then we get back to normal measures.
So little storm signals here
but that's all we're seeing there.
Otherwise, sort of normal trends,
not a whole lot of deformation at Norris.
And then finally looking at Steamboat Geyser,
the tallest geyser in the world.
There was one eruption during the month of December
right here on December 6th.
This is the temperature in the outflow channel.
All of this sort of up and down activity
are minor eruptions that culminate in a major.
And after that major eruption,
we see going back down to background temperatures,
basically freezing.
And then minor activity started up again here
on December 18th.
So it looks like Steamboat isn't quite done just yet.
This minor activity may lead to another
major water eruption of the geyser, perhaps early in 2023.
Well, that does it for the Yellowstone Volcano Observatory
update for January 1st of 2023.
Now remember, if you have any questions at all,
please feel free to email us at yvowebteam,
that's all one word, at usgs.gov.
Stay safe, stay healthy.
Have a wonderful new year.
Happy 2023.
We'll see you next time.
Bye-bye.
(gentle music)