July Public Lecture — USGS CalVO: It's not just earthquake country!

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Detailed Description

Volcanic eruptions occur int he State about as frequently as the large San Andreas Fault Zone earthquakes. California's "watch list" volcanoes are dispersed throughout the State and future eruptions are inevitable—the likelihood of renewed volcanism is on the order of one in a few hundred to one in a few thousand annually.

With Margaret Mangan, Scientist-in-Charge, USGS CalVO


Date Taken:

Length: 01:25:26

Location Taken: Menlo Park, CA, US


[ Silence ]

[ Music ]

[ Silence ]

- Good evening, again,
for another installment

in our monthly
public lecture series.

Welcome to the
U.S. Geological Survey.

My name is Leslie Gordon,
and it’s always my –

or usually my privilege
to introduce the speakers.

Can you tell I’m out of breath?
Because I ran over here. I was late.


I have a couple of
announcements, as usual.

One, I thought you might be interested.
The local fire department –

the Menlo Park Fire Protection District
is hosting a public free community event

a week from now on learning and
discussing about preparing yourself

and your family to survive
in the event of a disaster.

So whether that’s an earthquake
or a flood or a plane crash.

And it is a week from tonight.
It will be here in this room at 7:00 p.m.

And that’s the – if you
want more information,

either call the fire department
in Menlo Park or corner me.

I also want you to
come back next month.

Next month, geographer Jeff Sloan
will be speaking about New Eyes

in the Sky – Putting Drones to
Work for Scientific Research.

So that’s kind of the latest popular thing.
If you want to learn about how we

are using drones, not only to save time
and money and make it safer

for people to do certain things, do join
us next month on August 25th.

Tonight it is my pleasure to
introduce Dr. Margaret Mangan.

She is a geologist, a volcanologist –
a volcano geologist.

She is also the scientist in charge of the
USGS California Volcano Observatory.

Some of you may know that USGS
operates five volcano observatories,

and Maggie will explain
more of that today.

So Maggie is located here in
Menlo Park, but before she came here,

she started with the
U.S. Geological Survey in 1983

in our headquarters office
just outside Washington, D.C.

Then, in 1990, she moved to our
Hawaiian Volcano Observatory

and spent many years there,
including a stint as the

first woman scientist in charge at
the Hawaiian Volcano Observatory.

In 1998, she moved
here to Menlo Park.

And, as I mentioned, she’s now the head
of the California Volcano Observatory.

Maggie manages a staff of
over 40 scientists and technicians.

She leads the monitoring efforts
at eight threatening volcanoes.

She works with emergency management
authorities at all levels of government.

She’s also a course developer and
instructor for the Federal Emergency

Management Agency –
that’s FEMA –

volcano crisis awareness
training in California.

She has, as a scientist, responded
to numerous volcanic disturbances,

in Hawaii, Alaska, California,
and the Caribbean.

Margaret Mangan holds her Ph.D.
in volcanology from

Johns Hopkins University.

And throughout her career,
she has conducted field, laboratory,

and theoretical studies
to determine conditions

that trigger volcanic eruptions
and control eruption intensity.

She’s published numerous research
articles in prominent scientific journals.

And she is the editor-in-chief
of the Journal of Volcanology

and Geothermal Research.

She is also an elected fellow of the
Geological Society of America.

So please join me in
welcoming Margaret Mangan

to speak about the USGS
California Volcano Observatory.

[ Applause ]

Thank you, Leslie.
That made me sound really fancy.

I’m not, really.

But I do have a very interesting and
lively profession that I’ll pass some on –

some information on
to you today about.

What I’ll be talking about
is the relatively new, or young,

USGS California
Volcano Observatory.

It was established
in February of 2012.

And when we put together the
press release for rolling out

this new observatory of the
U.S. Geological Survey,

Leslie helped me
make this press release.

She said, we got to
get some quotes.

And so we got a quote
from the California Office of

Emergency Services, and we
got one from the state geologist

of the California Geological Society,
and one from our director.

But I put the quote from the
state California – the state geologist

of California, John Parrish,
that he gave us for our press release.

And I’ll read it out loud to you because
it really sets the stage for this talk.

California is the most geologically
diverse state in the nation.

We are known for our
earthquakes, landslides, floods,

but our nearly forgotten
hazard are our volcanoes.

And indeed, to a certain extent,
that was true.

For decades, there have been scientists
here in Menlo Park and elsewhere

throughout the USGS that were
studying volcanoes in California.

But what we hadn’t done as an
organization in the USGS is to

package them up in a – in a coherent
structure – a volcano observatory –

so that the information we had could be
passed on in a systematic and

effective way to civil authorities,
the public, and people who

need to know when
volcanoes are restless.

And hence, the formation
of the newly formed

California Volcano
Observatory in 2012.

As I said, the California
Volcano Observatory

is the baby of volcano
observatories of the USGS.

We’re all part of the
Volcano Hazard Program.

And we run five volcano observatories
and an international arm.

We see them there listed
on the slide there.

The California Volcano Observatory and
the Yellowstone Volcano Observatories

are headquartered here on the
Menlo Park campus, but we also

have the Cascade Volcano Observatory
up in Vancouver, Washington.

That is where our volcanic
disaster assistance program –

our overseas arms –
works out of.

And then, up in Anchorage, we’ve got
the Alaska Volcano Observatory.

And then one of my favorite
observatories, over 100 years old,

is the Hawaiian Volcano Observatory
out there in the Pacific Ocean.

As I said, we’re all part of
the Volcano Hazard Program

of the U.S. Geological Survey.

And we have a simple
aim as part of our program.

And that’s listed in the
lower right-hand corner.

I’ll read it out to you.

The USGS Geological Survey
Volcano Hazard Program

aims to enhance public safety
and minimize societal disruption

through the delivery of
effective long-term and short-term

hazard assessments
and forecasts.

It’s a very simple-sounding aim, but
indeed, it is quite complex to achieve.

There’s a lot of complicated science and
equipment and very smart people of all

walks of life that
contribute to that aim.

And we’ll learn a
little bit about it today.

So, before we go any further, I need to
drill something into your heads here.

And that is that California is
not just earthquake country.

It is also volcano country.

And in fact, if you look at those
bullets I have listed there,

volcanic eruptions occur
about as frequently in our state

as the largest San Andreas
Fault earthquakes.

And in fact, there have been
10 eruptions in the state of

California over the
last 1,000 years.

And the decades of science that we have
done here at the U.S. Geological Survey

tell us that the chances of another
California eruption are on the order of

about 1 in a couple hundred to 1 in a
couple thousand on an annual basis.

The last eruption in the
state of California –

anybody know
where it happened?

Yell it out.

[audience: inaudible responses]

Yay for you.

Very good.
Up in northern California.

Lassen Peak erupted about
100 years ago, from 1914 to 1917.

And in this photograph, which is
given to us courtesy of the

National Park Service, it shows the
little town of Red Bluff in 1915

when that Lassen Peak eruption
had its biggest bang.

We see a large column of ash that
is reaching up to the stratosphere –

up to 30,000 feet.

Now, this is a picture
taken from Red Bluff.

And the distance from Red Bluff
eastward to Lassen Peak

is on the order of
about 60 miles.

Now, our program – our observatory
and our larger program …

[croaking sound in background]
That’s an interesting sound.


- And that’s where we …
- Somebody brought their duck.


- Or it’s a seal.

- Don’t forget to come back.
You’re excused for that.


Yeah. Where was I?

In 2005 – well, really it was 2003
and 2004, our program went through

the process of ranking the threat
levels of all U.S. volcanoes.

The – well, I’m just
going to back up.

Because all those little triangles that you
see on that slide – yellow, red, orange –

those are our volcanoes that have the
potential to erupt again in the future

or are erupting now,
particularly along the Aleutian Arc

where Pavlof just went off
again today – Pavlof Volcano.

And of course, in Hawaii,
the volcano has been erupting

continuously since 1983.

But our program went through
and ranked the threat levels

of all those volcanoes –
all those young volcanoes.

And it turns out that there are
16 young volcanic vents –

volcanoes that are in
the state of California.

And of these, eight have the
most potential to harm or disrupt.

Those eight are shown by
the yellow and red triangles.

You’ll see some green triangles
there that are smaller.

Those are young volcanoes that
are deemed to be low-threat –

deemed through the research that our
geologists and our geophysicists do.

But those eight in the yellow
and red all have a zone of

partially molten rock
deep in their interior.

They’re listed on the
left-hand side of the slide there.

Medicine Lake Volcano
up in Modoc County

at the very northern
end of the state.

That last erupted
900 years ago.

Then we move over
to the beautiful Mount Shasta.

Hopefully you’ve all seen it at least from
the I-5 as you drive fast to the north.

Beautiful stratovolcano.

But a high-threat volcano.

That last erupted about 1,800 years ago,
but science can always be fine-tuned.

And we’re in the process of new
research that may change that date.

May end up to be a little bit older
than we had originally thought

that last eruption was.

As we move a little bit to the south,
we get to Lassen.

A hundred years ago,
it was an eruption.

We move further south
and a little bit west,

and we get to the
Clear Lake Volcanic Field.

Now, some people may not know
the Clear Lake Volcanic Field,

but you may know
Clear Lake in Lake County.

Or you may have heard of the
Geysers steam field geothermal plant

that provides so much
energy for the state.

Well, that lively geothermal field
is heated from molten rock

that is buried within the
Clear Lake Volcanic Field region.

Then we’re going to move a little further
south and to the – to the east again.

And we’re at the
Long Valley Volcanic Region.

Beautiful country just on the eastern
scarp of the Sierra Nevada range.

Just outside Yosemite where
all the crowds are is a beautiful,

beautiful country, and that is
also the location of

Long Valley
Volcanic Center.

We move south to
two desert volcanoes –

Ubehebe Craters in
Death Valley National Park.

Farther south,
Coso Volcanic Field.

Again, a site of an active geothermal
plant because there is heat supplied

from a zone of partially molten
rock deep within the system.

As you go farther south and
almost get to the Mexico border,

you end up at a very strange little
place called the Salton Buttes.

Has anyone ever
visited the Salton Sea?

It’s an incredible otherworldly


But they have the best birding that
I have ever seen, and I’m not a birder,

but my sister is,
and I’ve taken her there.

And she just – her and her husband
just were groveling at the beauty.

But it’s also
a volcanic system.

And again, it has an active geothermal
plant that’s producing a whole lot

of energy because there’s molten rock
under that part of the country.

Again, the red and the yellow triangles
are all volcanoes with molten rock

within their – within their deep guts
and are volcanoes that are ranked

as moderate, high,
or very high threat.

I call them my watch list volcanoes, and
these are the volcanoes that we monitor.

In a little bit, we’ll learn a bit
about volcano monitoring.

But I can’t help showing you this slide
because everybody knows earthquakes

in California, and everybody
knows landslides in California,

but here’s the juxtaposition of
volcanoes with our earthquake

hazard map on the left and our
landslide hazard map on the right.

And again, the triangles are our
watch list California volcanoes.

Now, as you can see,
there are certain volcanic areas

that are subject to
the double-whammy.

They are in zones of
high seismic hazard,

as shown in the bright red to
very hot – white-hot color gradations.

And then, over on the right-hand side,
you see some of those watch list

volcanoes are co-located with
areas of high landslide hazard.

Now, before we get too worried
about volcanic hazards,

I’m going to remind you
that these places are beautiful.

They are incredible natural landscapes
that draw visitors from all around the

world, and we’re very fortunate to live
amongst these babies – my babies.

Up in the right corner – well, let’s start
in the northern part of the state.

If I could work my –
oh, I can work it for a minute.

I have trouble with this mouse,
and I complained about it this morning

when I did the preview, but I was
told to just suck it up, and so I am.


So bear with me.

Medicine Lake Volcano in the northern
part of the state – Modoc County –

you see that on the skyline, there’s
this black – looks like a shadow.

It’s a shield-shaped volcano.

That’s Medicine Lake Volcano,
or part of it.

Medicine Lake Volcano also claims
the Lava Beds National Monument.

That’s part of
Medicine Lake Volcano.

As you move to the south, the beautiful
Mount Shasta – you can’t miss it on I-5.

Beautiful stratocone within the
Shasta Trinity National Forest.

Great recreational area,
but also a high-threat volcano.

As you move further south,
again, on the left-hand side,

you see the
Lassen Volcanic Field.

Now, that peak that erupted 100 years
ago is not what we’re looking at now.

Those were produced
in an eruption 1,300 years ago.

But if you look off to the right-hand side
of that photo, peeking up over that big

mound of lava is Lassen Peak, and that’s
the peak that erupted 100 years ago.

As you move a little further south
and a little bit to the west, again,

the Clear Lake
Volcanic Field.

That’s Mount Konocti –
a wonderful state park.

And you see part of the
lake itself in the foreground.

Now we go to the top of the slide again,
and we look at the eastern scarp

of the Sierras – the Long
Valley Volcanic Region.

We see a
wonderful ski resort.

I’m not a skier,
but I’m told it’s fabulous.

And it’s a
beautiful volcano too.

That is Inyo National Forest as well as
Devils Postpile National Monument –

all an attraction because of
their volcanic beauty.

As we move to the south,
we have those desert volcanoes.

We have Coso Volcanic Field
along the 395 that we see.

We see Red Hill
in the foreground.

And in the background, on the
right-hand side of that photograph,

you see those humps?
Those are lava domes.

All part of the
Coso Volcanic Field.

The other desert volcano is in
the very lower right-hand corner.

A series of overlapping craters
known as Ubehebe Craters

in Death Valley
National Park.

And then finally we get to that very
strange and wonderful place at the

bottom of our state – the Salton Buttes
with its wonderful birding opportunities.

And again,
a moderate-threat volcano.

So don’t lose track
of the beauty and the richness

that they bring to our state
as we go forward.

So why so many
volcanoes in California?

Actually, there’s about 500 –
well, actually, a little over 500

volcanic vents
in the state.

What I showed you on one of
my early slides were just 16,

the youngest of those with the
potential to erupt in the future.

But there are actually 500 vents.
Why so many volcanoes?

And that is because of
the diverse tectonics

that this west coast
of our nation supports.

So we see the state of
California in purple.

And this time,
my babies are in purple –

the purple triangles –
the eight watch list volcanoes.

And then we see
some markers that are

showing us plate boundaries
and plate motions.

I really need the – there we go.
Yay. Okay.

Watch it before it leaves.

Oh, see.
I didn’t even do anything, Leslie.


Well, you see where I’ve
labeled the Gorda Plate?

That little plate is diving underneath
the North American plate.

And that diving plate –
that oceanic crust,

which is high-density with respect
to the continent, which is lower density,

dives down in what we call
subduction zone volcanism.

And we see that in the upper-right
cartoon, I’ll call it, on the slide.

You see the plate –
the oceanic plate in brown

diving down
underneath the continent.

While it dives down, it heats up,
and it pressurizes as it descends.

And in addition, the mantle –
the upper part of the mantle

that we call the asthenosphere,
which is ductile and hot –

I think of it as ductile and highly
viscous, but can flow like peanut butter.

When that plate dives down,
that oceanic plate dives down,

part of that mantle oozes up
and brings its heat with it.

And that heat from deep within the
Earth causes partial melting of the slab,

of the crust – the continental crust
of the North American plate.

Waters are released
as oceanic crust,

and sediments dive down
in that subduction zone.

And the net result is
that magmas are produced.

And that is what those
little red teardrops in my cartoon

are portraying – the creation of
subduction zone volcanoes.

And in this case, it’s the
Cascadia subduction zone.

And it gives rise to our
northern volcanoes –

Medicine Lake,
Shasta, and Lassen.

As we move down in the state,
we’ve got another style of tectonism,

or tectonics,
that is creating volcanoes.

And that’s happening at a little
hub of very active tectonic activity

known as the Mendocino
Triple Junction.

And we see that on the slide,
and it’s pointing to this one point

where a transform fault known as
the Mendocino Transform Fault –

that’s one of those faults that
go like this – is impinging on that

subducting Gorda Plate but also
impinging on the San Andreas Fault.

And the whole shebang is moving
to the north as the gross motion

of the Pacific Plate goes forward
at about 5 to 6 centimeters a year.

So that Mendocino Triple Junction
is the Bermuda Triangle of volcanoes.

And in that cartoon in the middle
on the right-hand side, I’ve got

what I hope will demonstrate why we
have volcanoes at that triple junction.

It gives rise to the
Clear Lake volcanoes.

Because of the Pacific Plate
moving to the north,

that Triple Junction is
moving to the north as well.

And that slab –
that Gorda Plate slab

that is diving down in the northern part
of the state is moving along as well.

These plates are rigid,
and it leaves a void.

And that’s what that dashed
cigar shape is trying to show you.

And the void left by these motions, and
the geometry of these structures allows

that peanut butter mantle – that hot,
ductile mantle to go in and fill it.

And with it, it brings heat.
And that heat causes melting and

the creation of magmas, which give rise
to the Clear Lake Volcanic Field.

And also the
Geysers geothermal field.

So number two of our
tectonic situation in California.

But now let’s go down
to the southern half of the state.

That would be the
Long Valley Volcanic Region

and Ubehebe Crater and
Coso and Salton Buttes.

I heard somebody
say Mammoth.

Mammoth Mountain is part of
the Long Valley Volcanic Region.

Mono-Inyo Craters, Mono Lake,
Devils Postpile – all part.

Now, this has got
another reason for volcanism

in this southern part
of the state.

And the reason for volcanism here
is because there is extension.

The continent is stretching
and thinning because of

the shear that the
San Andreas is causing.

The motion of the Pacific Plate relative
to the North American Plate is causing

a shear that causes the – we call it
the Basin and Range Province.

And it’s shown there
in those diagonal lines.

That whole province is extending,
and the crust is thinning.

And when this crust thins,
look at the bottom cartoon –

you see parts of the crust thin
and drop down.

It’s unsupported.

And when that happens,
it allows that ductile mantle –

that asthenosphere hot mantle
to come a little closer to the surface

where it starts to melt and create
magmas that give rise to these

extensional volcanoes –
the Long Valley Volcanic Region,

the Coso Volcanic Field, the Ubehebe
Craters, and the Salton Buttes.

Now, there’s one other little nugget
that I want to pass on to you about

Salton Buttes, and that is this little place
is getting the double-whammy.

Because it has basin and range extension
that’s allowing the hot mantle

to come close and produce magmas,
but it’s also subjected to extension

from the East Pacific Rise.

That’s a divergent plate boundary
that is stretching and is

actually what created
that Gulf of California.

So we’ve got two processes causing
the extension at Salton Buttes.

So a whole range of
wonderful tectonics giving rise

to these watch list volcanoes and
all the other volcanoes in California.

We have so many tectonic settings,
and we also have the full range

of volcanic types, or volcanic styles,
at the volcanoes in California.

On the right-hand side, the top photo
and the bottom photo are showing you

examples of explosive eruptions
which produce volcanic ash

that reaches in columns
up to the stratosphere

and drift for hundreds of miles
across the landscape.

Near the vent, or the actual hole,
where these materials are ejected from,

there are deadly
pyroclastic flows.

These are hurricanes of
hot rock, gas, and ash

that come racing down the flanks of
the volcano at 60, 70 miles an hour.

And that’s what we see coming down
the flanks of that volcano in Mayon.

These types of eruptions, they’re
damaging, and they’re life-threatening.

We do have them in the – in California
and other places across our nation.

But at the other end of the spectrum, we
have what I call the drive-up volcano.

These kind of eruptions
are effusive eruptions.

And there’s a picture of me and
my field partner at Kilauea Volcano.

And we’re standing there
at the active vent.

And you can see the lava
bubbling up out of the ground.

It’s moving to the background
in the photo to feed lava flows.

These types of eruptions can be
very damaging and very disruptive,

but generally they’re
not life-threatening.

So here in California, we’ve got all
kinds of tectonic reasons for volcanoes,

and we also have all kinds of eruptions
that have occurred in the past.

And will occur
again in the future.

Possibly not in our lifetimes,
but certainly again in the future.

So ...

Let’s think a little bit about what
we can do with this information.

We know we have
a natural hazard in our state.

Can we forecast?
Can we predict the next eruption?

Well, we can to a certain extent.

I’ll talk about two types of forecasting.
One is long-term forecasting.

And then we’ll talk about
short-term forecasting.

So the long-term forecasting is
the job of the geologist –

the boots and hammer-in-your-fist
geologist that goes out across the

landscape and looks at rocks and
creates geologic maps and

discovers the eruptive history
of a volcanic center from its

birth through its teenage years,
and then, maybe a million,

two million years later,
its old age.

The eruptive histories
are incredibly important

in determining the
long-term hazard forecast.

What we see in the – in the photograph
is a colleague of mine named [Arcada]

who is looking at a series of
volcanic ash deposits

from the Mono-Inyo chain in
the Long Valley Volcanic Region.

The cartoon on the left
is a representation of that

Mono-Inyo chain of
craters and volcanic domes.

At the lower part of the cartoon,
we see labeled Mammoth Mountain.

And then,
as we move directly north,

we see a series of blobs in
brown that are the Inyo Craters.

And then we move a bit
further to the north

into the Mono Craters and then
into the beautiful Mono Lake.

Now, the geologist with the boots
and the hammer is able to determine

the eruptive history,
and that’s what we’re seeing

on the right-hand side
of that cartoon.

All the eruptions in the last
10,000 years are plotted in that diagram.

Not only do we have the ages of
these volcanoes from their research,

we also have the
style of eruption.

They can tell if it’s explosive
or if it was effusive

and the intensity of both of
those two types of eruptions

by looking at the deposits
the volcano leaves behind.

So it is this kind of
detailed information –

boots on the ground,
rock hammer in the fist,

that allows us to determine that
eruption within this Mono-Inyo chain

on an annual basis, the likelihood is
between 1 and a few hundred annually.

So that’s part of our
long-term forecasting.

Woo. I got really hot.
Are you guys hot? It’s the light.

Put me in the dark, Leslie.

Now, what I also want to
tell you about is

the role of the geologist
doesn’t stop in the field.

There’s a lot of framework science
that augment what we do in the field.

And this is also part of
long-term forecasting.

It’s science that is done in labs
and through experimentation.

And we’ve got a
beautiful suite of laboratories

here on the
Menlo Park campus.

And you see an array
of them posted in this slide.

What you also see is the result
of research that has come out of

the combination of detailed field
mapping, geologic mapping, eruptive

histories, and experiments of recreating
eruptive conditions in the laboratory.

And that’s shown in that
cartoon on the left-hand side.

It’s showing us
the details of

what lies within Mount St. Helens
in Washington state.

We know from field work and
experiments that there is a hot zone

of so-called basaltic magma down very
deep at a level of about 30 kilometers.

That’s about 18 miles, I think,
if I’ve done the calculation correctly.

We know that it’s
greater than 950 degrees C.

And we also know from these
experiments what it does

while it sits there and decides
if it’s going to erupt or not.

What it does in terms of
crystallizing and degassing

and eventually creating
a low-density magma

that wanders up the volcanic pipe
and eventually is shot out the vent.

So the combination of field work,
laboratory work, and experimentation

are what we use to make our
long-term hazard forecasts.

Now we’re going to move
into the short-term forecasting.

And that’s a story of sensors
and data streams – widgets.

Short-term forecasting
is possible because

magmas take a while
to get themselves to the surface.

And as they’re rising to the surface,
as we see in this cartoon on the left,

the magma breaks rocks to
create its conduit,

it burps up its gas as it depressurizes,
and it deforms the ground surface.

It inflates the ground surface
as it pushes its way up.

And these three things – the gas, the
earthquakes, the ground deformation –

can be measured with
very sensitive instrumentation.

I’ve showed you some of
these instrumentation packets

that are in the field.

24/7 they’re delivering data
to here in Menlo Park.

We partner with our colleagues
in the Earthquake Science Center

for monitoring volcanic earthquakes
in these regions, and that’s a

digital seismometer on the upper
right-hand photograph that you see.

You see Mammoth Mountain
there in the background.

To the left is a
GPS receiver just like

the GPS you have in
your phone or in your car.

There’s a GPS receiver that measures
very small motions of the Earth’s surface

on the order of a centimeter or a few
millimeters as the ground is inflating.

And that instrument is
relaying information to

the Volcano Observatory here 24/7.

The two lower photographs
are showing you gas monitoring –

continuous gas
emission monitoring.

You see that antenna on the
top of a bathroom there at –

Mammoth Mountain is in
the background, so we’re –

again, we’re in the Long
Valley Volcanic Region.

It’s sniffing out volcanic
CO2 in the atmosphere

and relaying that information
to the observatory here.

And on the left,
we see a hydrologic monitor.

It’s measuring temperature,
conductivity – which gives us

information on the amount of chlorine
in the water, and it is measuring depth.

Because volcanoes, they emit gas, but
they also very often disturb hydrologic

systems, and springs change when
magma is moving toward the surface.

These are some of our
real-time monitoring, and they

are what allow us to keep our finger
on the pulse of volcanic systems.

So now let’s see
where we go.

I think I’ll start with
the lower right-hand side.

And I’m going to tell you something
that’s special about volcanic eruptions

compared to other types of natural
hazards or natural disasters,

and that is the
time scale of warning.

That’s what that diagram
is trying to portray.

I have the time scale of warning that
you might get from a flood hazard.

You might get days
predicted by our NOAA friends

or our weather service
that a flood is coming.

Hurricane – you might get
some warning – days before

your area is hit
with a hurricane.

Earthquakes, wildfires –
not so much warning there.

You’re just faced
with the event immediately.

An eruption often gives you months,
weeks, and days of precursor activity –

those volcanic earthquakes,
the ground deformation, the gas,

and the hydrologic disturbances
that tell you something is amiss.

We can see something is amiss
in this seismogram on the left-hand side

from a 2008 eruption in Alaska –
Kasatochi eruption.

This volcano hadn’t
erupted for decades,

but it did have molten
rock deep in its roots.

Over the course of
about 24 hours,

seismic activity –
earthquake activity began to pick up.

And as you go, starting at
about the 11:00 mark –

you can see 11:00 on the
left-hand side of that

top seismogram – you start to
see the earthquake activity pick up.

Each one of those seismograms
are going for 24 hours.

So the top diagram is August 6.
The bottom diagram –

the continuous record
is showing August 7,

starting in with earthquakes that are
just overlapping with each other.

There’s so much earthquake activity.
The ground is shaking.

And providing the clues
that an eruption is on the way.

Anybody see where the eruption started?
It’s kind of counterintuitive, actually.

And since you’re all very polite here,
I won’t point at anybody and ask to –

ask you to read this seismogram,
but I will notice there is

a little yellow sign there
that says, “Eruption onset.”

So there were more than 24 hours
of time to prepare for an eruption.

Eruptions starts, and then
look at the seismogram.

It goes quiet, almost.
Relatively speaking, anyway.

And that’s because, once the
magma comes to the surface,

it’s cleared its pathway.

It’s kind of got an open throat,
and it is just singing.

So that precursory activity actually
allowed the Alaska Volcano Observatory

to notify the National Fish and
Wildlife Service crew that was

on this little island of Kasatochi
where there is nowhere to hide

that they should
come off the island.

And they did. And 10 – about 10 hours
later, the volcano erupted.

The island was coated in pyroclastic
flows and ash, and lives were saved.

This short-term forecasting
requires experience.

It requires that the volcanologist
has seen the seismograms or the

deformation records or the gas records
from other volcanic eruptions.

So, to a certain extent,
there’s a lot of pattern recognition

that goes on to
short-term forecasting.

But these days – I’d say the last decade,
last five years, we’ve gotten increasingly

sophisticated with our science to move
beyond pattern recognition and to start to

model processes that allow us to
more tightly constrain our forecasts.

And that diagram that you see
up in the upper right-hand corner

is one such tool that we can use to
better constrain our forecasting.

This is the result of sophisticated
modeling – a technique called

waveform matching that allows the
seismologist to take a very

busy-looking seismogram and
parse out all those little squiggles

and extract the most
pertinent information.

And that gives rise to that block there.
Well, that block is a volume

at a depth of about 21 to 20
kilometers below a volcano.

And within that block
are these circles.

And the circles
are colored.

Each circle
is a earthquake.

And as you can see, they go from
red to yellow to aqua to dark blue.

That’s a time progression.

So with sophisticated modeling,
we’re able to see the actual movement

over a kilometer space
of volcanic fluids

moving through the
Earth and cracking rocks.

So experience,
the basis of pattern recognition,

and moving into sophisticated modeling
is improving our ability to forecast.

What do we do
with these forecasts?

It’s not good for me to tell Maurizio,
my colleague, a geodesist,

that, mm, looks like an eruption.

We need to tell
people that need to know.

And we have –
all of our observatories –

California Volcano Observatory
as well – have a operation center where

the data flows in,
and that’s what this –

I guess you would call it a hierarchy.
I don’t know.

What would you call that
kind of diagram? It has a name.

But I can’t tell you it right now.

The monitoring networks –
they’re pulling in the real-time data

from the field – deformation,
earthquake, gas emissions –

to the scientists in the operation
room where the data is assessed.

And, if need be, that information
is delivered to the

emergency management and
civil authorities in the region.

And that’s what all those
agencies that are listed there.

Data comes in.
It’s interpreted.

And then we scientists seek to
speak to the people that

take care of people and keep things safe
so they can use our information.

You’ll notice also that we’ve
got an arrow out to the public.

We’re very aware that the
public needs to know as well.

So there’s a fact sheet in
the back that I hope you’ll take.

We have a – maintain a website
and up-to-date volcano information,

not only in California, but throughout
the world, you can find on websites.

The website URL is
on the back of this sheet.

We also do a lot of public lectures
like this one here as well as speak

to the media and try not to get
ourselves in trouble when we do.

I did say that we need –
scientists need to speak to people.

They need to speak to civil authorities.
They need to speak to the fire

department and the police department
and the forest ranger and the public.

And we need to speak in a
way that they can understand.

So we’ve worked very hard
over the years in our program

to get rid of the science-speak
from a lot of our alerting.

We can follow up with all kinds of
grisly details if people want it, but we

do have an alert level system that’s
fashioned after the weather service.

All our volcanos currently in
California are at the normal level.

We go from normal,
advisory, watch, warning,

with increasing
precursory activity.

Those are for
hazards on the ground.

We also have an
aviation alert level scheme.

Because some of those
explosive eruptions

are putting ash
into the stratosphere.

And so we have a separate code
for atmospheric hazards,

and those go from green
to yellow, orange, and red.

Let’s see.

Right now, in the Aleutians,
we have at least one volcano

that’s in the watch mode
and one in the advisory mode.

In Hawaii, Kilauea Volcano
is in the advisory mode,

and I think Mauna Loa
might be as well.

So we use these things.

So this is part – and the final product
of our short-term forecasting.

How do we convey
those long-term forecasts?

The long-term forecasts show up
in the upper left-hand photograph.

You see a geologic map.

That is the basic information
on each volcano.

It’s got all the gory details.

Some people don’t want to
read the big map.

They just want to know
what they need to know.

So that is distilled in
a secondary product

that we can a volcano
hazard assessment.

And that’s in the lower
left-hand part of the diagram.

This volcano hazard assessment is
giving the long-term forecast – what the

potential for eruption is in the future and
what kind of eruption might it be.

Might it be effusive?
Might it be explosive?

How long might it last?
How far may its reach be?

That’s all in this long-term
volcano hazard assessment.

It’s a forecast.

Also in this assessment is
our bread and butter,

and that is the
volcano hazard zone map.

And that’s what we see on the
right-hand side of this diagram.

This one’s for
Lassen Volcanic Center.

The very bullseye in the center
of the map is where Lassen Peak is,

and that’s the location of the
eruption about 100 years ago.

That pink splotch is the area close to
the vent where you could have these

dangerous hurricane-force pyroclastic
flows during explosive eruptions.

Outward from that, you see some
tentacles of red and yellow, and those

are areas that are prone to lahars.
Those are mud flows.

When magma comes toward the surface,
the heat is supplied to any glaciers

or ice and snow
on the volcanic center,

melts it, and starts a mud flow
that follows the drainages.

And then finally, on this hazard map,
the outer dashed line that makes the

circle is the area within which
we know from our

geologic mapping and hazard
analysis studies is prone to

at least 2 inches of volcanic
ash deposit, or ashfall.

Now, during an eruption,
this whole circle wouldn’t be filled.

The whole footprint
wouldn’t be filled.

Of course, the wind is going to
take it in one direction or the other.

The prevailing winds
are to the east.

On a different wind day,
they might go to the west.

So that outer portion of the hazard
map is showing the ash hazard.

And ash is the most
far-reaching and enduring

volcanic hazard in
active explosive volcanoes.

So because we have
these hazard zone maps,

we can get some help from
our geographers here at the

U.S. Geological Survey, and they can
tell us, well, what’s in harm’s way.

They have access to all the geospatial
data and can map it up in GIS and tell us

things about population centers,
about infrastructure, about roadways.

This diagram is showing our watch
list volcanoes, again as triangles.

And the dashed circles
that are around all those triangles

is that 2 inches of volcanic
ash hazard zone criteria.

So anywhere inside those circles
one might expect 2 inches

of volcanic ash should
an explosive eruption occur.

It’s also showing you that,
although these volcanoes are

relatively contained within their
spatial extent in terms of the

cones and the lava flows, the
volcanic ash hazard covers counties.

And in fact, during an explosive
eruption where the ash goes up

into the stratosphere, ash can go for
hundreds, if not a thousand miles,

depending on wind speeds and
the intensity of the eruption.

So what do our geographers –
it looks like I have just a –

well, a few minutes left, and I’ll
keep going until you tell me to shut up.


Let’s see what our geographers tell us
about the northern part of the state.

I call that my trifecta.
It’s Lassen, Shasta, and Medicine Lake.

And those volcano hazard zones –
those ash hazard zones are overlapping.

So that’s my trifecta.

How many people live
within that hazard zone?

Well, the geographers tell us
that the live-work population,

the permanent population,
is a little over 100,000.

You see that on
the diagram then.

That’s not very much when you think
of the entire population of the state.

But we have to consider not only the
live-work population, but we also have

to think about the people that might be
passing through on a temporary basis.

And that’s what this right-hand
side of the diagram is showing.

It’s showing what the geographers
call the transitory populations.

In the upper right, we see that, within
that volcano trifecta, in that hazard zone

of 2 inches of ash, our roads are carrying
over 25 million vehicles annually.

If we look in the bottom part
of the slide – and this should

come to no surprise because
volcanoes are so beautiful –

the transitory population within that
trifecta of overlapping hazard zones

is on the order of
2-1/2 million annually.

And these are people that are visiting
the national forests, the national parks,

the state parks – there’s a
few museums in there.

National parks is Lassen Volcanic
National Park, it’s Lava Beds National

Monument, it is Shasta Trinity National
Forest, it is Modoc National Forest.

And there’s that beautiful
Shasta Lake area – state area.

So we not only consider that there is
a life-work population at risk.

There’s also the
transitory population

that one has to think about
in these local areas.

But I’d submit to you
that it’s not only just

the local areas that
we need to think about.

Not only the permanent people.
Not only the transitory people.

We can also
affect the entire state.

And on the next two slides are going
to show you why I’m saying this.

First and foremost
is the ash hazard.

So this messy map on the left-hand
side was given to me from FAA.

And those lines – the state
is scribbled in there.

You can see California
and southern Oregon

and Nevada and
Arizona labeled.

But those lines are
the jumbo jet routes.

Those jumbo jets traveling
at greater than 18,000 feet.

As you can see, they pass right over
those volcanoes that have the potential

to create a volcanic ash plume that can
be up at 30,000, 35,000, 40,000 feet.

Our friends in geography can
dig into the FAA data and unearth

the facts that are shown in that
histogram on the right-hand side.

That is the flight data –
the count data – daily flights,

number of flights passing
over those volcanic centers.

In this case, it’s Shasta, Lassen,
Medicine Lake, and Long Valley

on a daily basis.

And you can see that Shasta,
Lassen, Medicine Lake –

that trifecta that I like to talk about –
on the order of 200 to 400 flights

passing through that hazard
zone on a daily basis.

If we make the assumption that
most of these are probably jumbo jets

filled with people, those jumbo jets
are 200, up to 500, passengers.

We know how crowded
those things are these days.

That means that there are many
tens if not hundreds of thousands

of people passing
through these – air space.

And volcanic ash
is not good for airliners.

Ash is ingested
in the air intake.

It clogs up the little pores that allows
the air to pass through and deliver

oxygen to the combustion the engine
runs on and can bring down a jetliner.

The pilots and the FAA
and their various other agencies

have gotten very savvy
about looking for volcanic ash.

So they can avoid it,
but it will cause rerouting,

and it also sometimes
causes the close-down of airports.

So big economic disruption
when an explosive eruption occurs

that may have statewide,
even international, consequences.

I’ll show you this slide,
which shows our utilities –

our high-voltage lines
that pass through California.

Two very important features –
I’ll just touch on one of them.

The Pacific DC Intertie –
that is a high-voltage system

that is coming in from Washington
and Oregon – the hydroelectric plants –

and delivering about 4,800 megawatts
to the state of California.

And it’s delivered throughout
the grid from northern,

midsection, and all the
way down to L.A.

4,800 megawatts is
about 4 million people,

if you – if you
deliver that to homes.

Volcanic ash does not like –
well, let’s turn it around.

High-voltage lines
do not like volcanic ash.

When volcanic ash is wet,
it is very, very conductive.

And in that lower right-hand side of the
slide, you see flashover that’s occurred

when only a slight dusting of wet
volcanic ash has hit those insulators.

In fact, it’s only 3 millimeters.

But still, the potential for
explosive volcanic eruptions

to disrupt that power grid that
feeds through the state is quite real.

Another thing – you know, in California,
we’re always concerned about water.

And the volcanic systems in the state
can disrupt our water delivery systems.

So again, a volcanic eruption
up there in, let’s say,

Modoc County can
affect the entire state.

And that’s because that trifecta
is an important watershed.

It’s the upper
Sacramento River.

It is Lake Shasta and Trinity Lake –
important reservoirs.

It’s the Pit River, which again,
is another important water source

for the entire state.
That has the potential to be

disrupted by an eruption of Lassen,
Shasta, Medicine Lake.

Again, not just a local problem
for those northerners.

It’ll affect the entire state.

You can – you can talk also
about natural gas delivery.

About 90% of our natural gas comes
from the Malin hub, which is coming

down from natural gas fields in Canada,
the geographers tell me.

That’s fed into our system.

And again, those pipelines and
the above-ground connectors

and metering stations are all in
that northern California trifecta.

So two more slides,
and thank you for bearing with me.

Because I do enjoy talking,
maybe too much.


California – yes, it is earthquake
country, and we must be aware of that.

But it’s also volcano country.

And the likelihood of an eruption
in the state of California

is on the order of 1 in a few hundred
to 1 in a few thousand annually.

There are eight volcanoes in the state
that we monitor that we have

the ability to identify the precursors
of said future eruption.

We also have the ability to communicate
this to emergency response people,

to civil authorities, and to the public in
a way that’s clear and hopefully useful.

Our program is working
very hard to modernize

all of our volcano
monitoring networks.

In the state of California, there are
at least four of the volcanoes that do not

have either modern instrumentation
or enough instrumentation.

And that’s the case
throughout the nation.

And so very quietly, while earthquake
early warning is going forward,

we volcanologists have been
working since 2006

on the National Volcano
Early Warning System.

So we are gradually building
our network infrastructure.

We’re gradually building our
scientific knowledge that allow us

to understand the
long-term hazards –

the long-term forecasts – those
boots-on-the-ground studies that we do.

As well as becoming increasingly
sophisticated with the modeling

that help us understand the processes
that lead to volcanic eruptions.

And this is – we’re out of these now,
but it does describe a coherent program

that goes beyond any one
of our five observatories.

It is a nationwide effort
to develop an early warning system

that is effective
and successful.

I guess those two things
go hand-in-hand.

It also is a program –
this National Volcano

Early Warning System is an effort
to really reach out to stakeholders.

And that series of photographs
on the right-hand side are meetings

that we’ve held in the California
with the Office of Emergency Services,

with the California Geological Survey,
with the Department of Transportation –

I forget who else in mixed in here –
trying to help them understand

what’s in their district and what the
impact and likelihood might be.

This final slide are the
people of the observatory.

These are my colleagues.

I love every one of them.

I am the manager of them,
and they all cause headaches,

[laughter] but they are incredibly
dedicated scientists.

High-quality science with
enough quirkiness to them

to be enjoyable to work with.

And these are the
people that are

watching over your
California volcanoes.

So I will take some easy questions.

Or I’ll just leave. Whichever you prefer.

[ Applause ]

- As usual – someone knows the drill –
we have two microphones,

one in each aisle, and I ask you
to please get up, get in line,

and stand at one
of the microphones.

Because not only do we want to hear
your questions, but we have people

watching online, and they want to
hear your questions as well.

So please do get up and
use one of those microphones.

If that is a great difficulty for you,
just wave me down,

and I’ll bring you
a microphone.

So go ahead with
your first question.

- Have you talked to Caltrans at all
about how long it might take

to reopen I-5 after
a 2-inch ashfall?

- I have given a couple lectures
to various Caltrans regions.

The trouble with volcanic ash is that it –
it’s deposited, and that makes roads

impassable for a
couple different reasons.

One is, ash is gritty. And it gets into
mechanical parts and erodes metals.

So your car may not work.

But it also creates very slick conditions
and poor visibility on the road surfaces.

But once the eruption stops,
there’s ash all over the place.

And the winds blow it back
and forth and back and forth.

So it can go on for weeks,
if not months, of cleanup.

So it’s a long recovery process.


- Yes. You talked about
being able to model

a rising magma pocket and, you know,
then that cube that you showed.

Have you been able to, with your on-the-
ground sensors, triangulate with enough,

you know, data points and watch in
real time as the thing actually rises?

- That is what we can do
with a good – with a good network.

- Okay, thanks.

[ Silence ]

- Sir?
- Yes. I’ve got two quick ones.

Mount St. Helens, which is
a mere 36 years ago –

well within our lifetimes –
that was pretty spectacular.

That’s not likely to happen again
in our lifetimes, I wouldn’t think.

That’s probably out
there a ways, I guess.

You have something like that happen.
You have certain magnitude earthquakes

that happen – the bigger they are,
the less frequently they happen.

I imagine it would be the
same thing with volcanoes.

- Yeah. You have a big blow-out.
- Yeah.

- A hundred years later –
100,000 years later, you have

another of that magnitude.
- Yeah.

This won’t happen in our
lifetimes again – not that mountain.

- Well.

In California’s history,
there have been very large eruptions,

but in the last 10,000 years,
there has been nothing that matches

what happened at
Mount St. Helens in 1980.

- Yeah.

- That’s good news.
- Yeah.

- Question number two.

- Let me ask you this way.

We have earthquake faults up and
down the state around different areas.

Is it possible that some of these
earthquakes can cause a volcano?

Or is it the
other way around?

- That is an awesome question.
- Yeah.

- It’s a really good question
because I – I even fed you

that question because I talked
about the double-whammy.

And that is, some of the volcanoes
are in zones of high seismic hazard.

And across the globe, there have
been times where a volcano

was just on its tipping point
that have been triggered by

a large regional fault-type
tectonic earthquake.

Places we think about that in
California are Clear Lake

Volcanic Field because the San Andreas
Fault zone runs up through it.

Down at Salton Buttes,
the San Andreas –

southern end of the San Andreas Fault
zone runs into the Salton Buttes area.

And then, over in eastern California,
there’s a big fault system

that runs through the
Long Valley volcanic system.

Gave rise to a very large
earthquake in the 1800s –

the old Owen Valley

So there is the potential
for a double-whammy.

- Yeah. Thank you.
- Okay. Sir?

- I don’t see – or maybe
Long Valley is part of this –

Mammoth Lakes?
Is that …

- Mammoth Lakes is the town
that is nestled in the

Long Valley volcano region.
- Okay. Okay.

I wasn’t quite sure.
Okay, thanks.

- You mentioned the trifecta
at the north end of the state.

And I noticed that
Medicine Hat, I think, is a …

- Medicine Lake?
- Medicine Lake – thank you –

is a, you know,
low-slope shield volcano.

Whereas, like, Shasta is
a much pointier –

so if they both have similar formation
mechanisms in terms of the

subduction zone, why are
their lavas so different to cause,

you know, high-slope
versus low-slope volcanoes?

- Good question.

And I tricked you with Medicine Lake –
that photograph I showed you.

There’s a lot of that effusive type of
eruption that creates that gentle shield,

very similar to what we
see in Hawaii, at Medicine Lake.

But not in that photo
are the larger deposits

of explosive volcanism
at Medicine Lake as well.

So Medicine Lake has
that end member –

effusive and very
explosive as well.

It’s heavier on the effusive end, but it
does have explosive volcanism as well.

Mount Shasta, that beautiful
stratovolcano, that kind of volcano

is many, many explosive
eruptions to produce it.

But it also – around and about and down
on the lower slopes and into the forest,

you’ll see the products of effusive
eruptions that occurred at Shasta.

And the same is true
for Lassen as well.

Just what made the pretty
picture is what you got. [laughs]

- Thanks.

- I have a less serious
question for you.

I saw the photo of you and your
colleague walking on the lava field

at Kilauea, and it looks like one of
the people in the photo is maybe

dangling something on a string.
- Ah.

- And I’m curious if this is a sensor
or if this is maybe something for fun,

like you’re cooking a steak
or something like that.


- Never accuse us
of having fun.

We are serious scientists of the
federal government. [laughter]

- So it’s a steak.

- Actually, I am in the front,
and my colleague,

Christina Heliker,
is in the back.

And what she has dangling – we call
it the dead rat photo. [laughter]

What she has dangling
from a stainless steel cable

that’s about that fat
is a piece of lava.

We actually just sampled
that lava flow –

that active, bubbling area that
you see as kind of orange and red.

So we take the cable,
and on the end of the cable

is this metal hook
that looks like this.

And we throw it in, and then
it’s really hard to get out.

You’ve got to pull.
There’s two of us pulling because

the lava – even though it looks
kind of fluid, it’s very viscous still.

And so you yank it up,
and as soon as that hook hits the air,

the lava clenches to
this brilliant black glass.

And that is a sample of lava
right out of the vent that we use

to help us keep track of the
plumbing inside the volcano.

So that’s a serious endeavor.
And it’s also kind of exciting, but …

- Thank you.

- Sir?
- Yeah, a question about the

Long Valley called there.
Around 1980, very late ’70s,

lots of earthquake swarms there, but …
- Yes, indeed.

- So what’s going on now?

- Well, I showed a slide in the preview
talk I did for my colleagues here at noon

that showed that system in terms of
its history of unrest since 1980.

And as you said,
from 1980 through –

really through the – 1998, periods
of very strong unrest.

Now, we all know what unrest is now.
It’s earthquakes, ground deformation –

in this case, uplift of the ground surface
on the order of about 80 centimeters.

So, like, a yardstick worth
over those years total.

As well as the emission
of volcanic gases.

And in this case, it’s a
carbon dioxide gas coming out.

I wet my feet – after leaving Hawaii,
I took my baby steps in California

volcanoes with my good friend and
mentor Dave Hill, who was

the scientist that was in charge
of leading the monitoring effort

during that
very restless time.

I started following
in his footsteps in 1998.

And in about 2000, that unrest stopped
and Dave retired, and I appreciated

him keeping things quiet for me
as I took over the reins.

But it’s been relatively quiet since.
There have been earthquake swarms that

raise our eyebrows a little bit, but most
of them are not felt by the townsfolks.

They’re usually
under magnitude 3.

The ground is uplifting,
has been uplifting

from about 2010 at a rate of
about 2 centimeters a year.

So it’s still bubbling along, but nothing
like the ’80s and ’90s, thank goodness.

- The Salton Buttes.

Could you more
closely define the location?

- Salton Buttes – well, all you
have to do is look on Google Earth.

And look for the Salton Sea.
Salton Sea is a huge sea.

When you stand on one shore, you look
across, you don’t see the other side.

It looks like an ocean.

But, on the southeast side of the shore of
Salton Sea are five little obsidian buttes.

And those are the Salton Buttes.
It’s in Imperial County.

This is a strange name, but the
Sonny Bono Wildlife Refuge is there.


So you could Google that, and that’ll
give you directions to the place.

But it is a fantastic,
as I said, otherworldly place

where you can see birds
and a strange manmade sea.

I won’t tell you the story of that,
but it involves a bunch of

silly things happening.
So look it up.

Go home and look it up.
- Thank you.

- The creation of the Salton Sea.

Yeah. So Imperial County, the
Salton Sea, you’ll find the Salton Buttes.

- [inaudible]
- It is. Yes. Yes, that’s true.

Okay. Who’s next?
And then I’m going to ask a question.

- You said that there were numerous
volcanoes around the United States that

have no monitoring equipment or
antiquated monitoring equipment.

If one of those volcanoes was to
start to become active, obviously

the deformation and gas detectors
wouldn’t catch that.

But would the seismic equipment
in other places be sensitive enough

to alert somebody so you
can send somebody,

or a drone, or somebody
out there to –

somewhere in Arizona or
New Mexico or somewhere,

where one of these things
is likely to happen?

Nobody’s really
watching that closely?

- Yes. The nation’s seismic network
can pick up, in a – you know,

it would probably be a
rudimentary signal,

but it would give information
that something’s going on.

And our program – we maintain
a cache of ready-to-go equipment.

We can go out with our portable
seismometers and we can set up

GPS receivers and take
measurements in short order.

But we don’t like to play
catch-up with active volcanoes.

We want the instrumentation
on the ground in the first place

so that we have quality information
coming in at the get-go.

- How long does your
field gear out there last?

If you put in good equipment,
you know, GPS and gas monitoring?

- You know the worst
thing that happens,

or what diminishes the lifetime
of a sensor is actually theft.

That’s not the case in Alaska
where I’ve worked before

because there’s
nobody around.

But having things walk
away is a – is a problem.

The – I would say the sensors
that do degrade the quickest

are those that are
in hot places.

So some of the things that
we use to measure hot gases

or temperature are things that
need to be replaced frequently.

A seismometer – a seismometer
out in the Long Valley Volcanic region,

it can be there for decades and
be a good working instrument.

It may be kind of antiquated in giving us
analog data instead of digital data, which

reduces our ability to model the data as
quantitatively as we like, but it lasts.

- Is the expense in the gear or
the sort of footing to put it in?

- I would say there’s an upfront cost –
a seismometer of the sort we use

and its telemetry materials to get the
data out is on the order about $15,000.

The real – the real cost,
though, is in the maintenance.

You’ve got to keep these things going.
And that’s the real cost.

Okay. Can I ask a question, Leslie?
- Thanks.

- Okay. Let’s see.
I’m going to ask that gentleman

with the black-and-white shirt there –
and you have on glasses,

and you’re holding a phone,
it looks like.

Why are you here tonight?

- [inaudible]

- Is that all you’re going to tell me?

It’s heartening to see folks
come and hear science.

So I’m just asking.

- Well, I was just hoping Pat [Gruner]
would show up tonight.

Is Pat Gruner here?

So there you go. See?
She’s here.

- Well, who is he?
What’s he doing here?

- No, Pat. That’s a she.
She’s over there.

- She. Hi.
Why are you here, Pat?


This is the last victim.
I won’t – I won’t bother anybody else.

Tell me why you’re here, Pat.
I’m glad you are.

- Because these two
guys brought me here.

- Oh, really?

Under protest?

- No. I was interested in the subject.
- I’m very glad.

Well, thank you so much for coming out.

It is a really a fun thing for me to do,
and I hope you enjoyed it.

[ Applause ]

- And we look forward to
seeing you all next month.

- Don’t forget.
Take one as you leave.

[inaudible background conversations]

[ Silence ]