welcome to week 7 of the IntroDUCKtion
2020 faculty perspective series
today's roundup of faculty talks will
feature faculty from the school of
journalism and communication
the department of indigenous race and
ethnic studies the department of earth
sciences
the department of biology and cinema
studies
in a moment i will turn the program over
to our presenter
Dr. Thomas Giachetti before that though
i'm going to review a few things that
are important to keeping you on track to
complete your IntroDUCKtion requirements
all students watching this program
should make time to submit your
reflection of the session as soon as
we're done
you can do that at community.uoregon.edu
your reflections on the individual
faculty perspectives programs
don't have to be long but we do want you
we do want you to share
what you've learned generally speaking
taking time to reflect in this way is a
proven way to improve your retention of
material
and is a habit of tons of successful
students
if you're a student who wants to earn a
credit as part of IntroDUCKtion
you need to select all the faculty
perspectives within two full tracks
plus four additional talks and submit
reflections on all twenty
you'll also need to submit a longer
capstone reflection on the entirety of
the programs and what you've learned
finally for those students who are
watching live remember that our faculty
members
answer your questions at the end of at
the last segment and they do that live
on camera
during each one of these programs if
you're a student watching live in zoom
please use the Q&A feature at the bottom
of your zoom screen
to ask our faculty presenter your
questions
so at this time i'm really excited to be
able to introduce you to
our faculty presenter for this session
in this week's environment and climate
change track
Dr. Thomas Giachetti explores what what
can be learned about
an explosive volcanic eruption from the
deposits
it leaves behind welcome Dr. Giachetti
thank you
good afternoon everybody so um my name
is Thomas Giachetti just said i'm an
assistant professor
in volcanology in the department of
sciences here at the university of
um oregon and today since we cannot
really do that
as we would do in normal times i will
try to
have you go outside and see things in
the wild and what we can learn
about volcanoes from the deposit they
leave behind
so a little bit about me one of the
first things you can probably notice is
that
english is not my mother tongue i'm a
french volcanologist i was born raised
and actually educated in france i got my
phd in friends
and i moved to the u.s about
10 years ago nine years ago actually
for work i um got a postdoc
in houston texas and then i moved to
annabelle michigan and i moved to the
university of oregon to start this
position of assistant professor only
five years ago
one thing you need to know about me is
that i'm doing this job really by
patient
all these pictures that you can see
right now on the screen i've had the
chance to take them
either during my studies during my phd
or during my work here at the university
of oregon or even during vacation
like those pictures from hawaii or
stromboli in italy
why did i decide one day to become a
volcanologist
well that's because thanks to i should
say
these guys maurice and catcher craft
that you can see here in the middle of
the screen
who were french volcanologists who
tragically died in 1991 during an
eruption
and i was 12 i was sick maybe the flu in
the middle of winter and i turn on tv
and i see a documentary about their life
with all the pictures that you can see
around them here on the screen
they took these pictures and i quickly
become
amazed by how powerful can be volcanoes
and
even without knowing anything about
geology you can see red you can see
gray you can see lava flow you can see
very big explosion
you can see names from all over the
world the us the
indonesia tanzania here on the screen of
iceland
and so i decided when i was 12 to
try to be a volcanologist and so uh
moving from the north of france where
there's absolutely no volcano to the
central part of france where there are
so many nice volcanoes called the
chandipuri where i did all my studies
and my phd
to the us uh to find a postdoc and as i
told you
a position here at the university of
oregon and i will show you in a moment
why it makes so much sense to have
volcanologists here at the university of
oregon
so when i saw these pictures and
studying my studies i quickly realized
that not only
volcanoes are nice and beautiful and
there's always sound and
and vision and even smell associated to
them
they are also very dangerous more than 5
million persons were affected by
volcanoes in the 20th century
more than 90 000 of them were killed and
as you may remember from your i don't
know
high school classes the earth is divided
the surface of the air is divided in
several large tectonic plates
and so wherever you've got boundaries
between tectonic plates you've got
volcanism so that's what you can see on
the map
here where you see triangles for all the
volcanoes that erupted either during the
last century or sometime
in the last 10 000 years and as you can
see they are not
completely randomly distributed on the
surface of the air but
um but follow boundaries in between
uh plates and you can see that most of
them are actually
located on subduction zones so that's
when one plate is going beneath the
other one and that's where
volcanoes are usually the most dangerous
you can see some pictures of the bar at
the bottom
of some of the surface processes that
these volcanoes subduction zone
volcanoes can produce
on the right you've got lars from
monsantellans which is just three-hour
drive from eugene
and on the left you've got um ashfall
from mon pinatubo in the middle
pyroclastic flow bioclastic surge from
the same eruption of mount pinatubo in
philippines in 1991.
so if you look at the map again you see
a very thick
black line that is crossing the pacific
plate
and so if we look at the cross section
of of the pacific plate
more or less you can see the different
types of volcanoes and different types
of volcanism
that you can get at the surface of the
earth so if we look at this big picture
starting from the left you've got the
subduction zone between two
oceanic plates so that would be
places like japan or new zealand for
example
on the extreme right you've got um a
continental rift so that would be for
example volcanoes like newberry volcano
some of them
some of you maybe don't know newberry
we'll see that in a moment
and in between you've got a continental
subduction zone so like our cascades
volcanoes here in the pacific northwest
you've got the middle mid oceanic ridge
that's where the oceanic crust
is being produced everywhere on earth
that's actually where
more than 75 percent of the magma
produced on earth
is produced beneath kilometers of water
so a volcanism that we have a hard time
to witness because it's really difficult
to go there
and in between um the shield volcano so
that's a type of volcano that is built
for an
hot spot so that would be hawaii of
course
and so as i said before subdictions on
volcanoes are usually the most powerful
and the most dangerous so why do we
study volcanoes
of course to understand why they are why
they can be so dangerous and how to
protect population from these volcanoes
and why do we do it here in oregon well
if you look at this map where you see
eugene here in the middle with this
green dot
and you just trace a circle of 1000
kilometer radius you can see that we've
got
almost all types of volcanism so
starting to the top left with
um subduction zone volcanoes like
monsantelens
so that's a picture from its eruption in
1988
sorry in 1980 on the top right we've got
an hot spot but not through a
continental crust this time but through
sorry not through um or sanicrest but
for a continental crest this time that's
the
yellowstone which is also a national
park on the bottom right we've got
newberry volcano which is again about
three hours drive from eugene i really
encourage you to go there if you can now
or later when you come to oregon
that's really such a nice place beyond
like its
um richness in in in in volcanic
features
and on the bottom left you can see the
juan de fuca midocyanic
ridge so that's a picture that was taken
several hundred meters
uh beneath the c surface that shows
um here what we usually call a black
smoker so that's a hydrothermal
fluid being released at the bottom of
the ocean and making this a very dark
gray
smoke-like feature
so um actually if we look um at eugene
and and the cascades
the united states geological survey or
usgs who is in charge of monitoring
our volcanoes here in the u.s has
classified 12 volcanoes
as having a high to very high threat
potential
seven of these volcanoes in the cascades
that you can see here with the right
uh the white dots on the on the
on the map on the left uh seven of these
volcanoes have erupted over the last
um 250 years and the last major
eruption is only 40 years old actually
this year
and it's the eruption of uh
monsantellans or lowell club
um as it's called by the native uh here
but the big eruption the last very very
big eruption
in the pacific northwest is that of mont
masama
that created cradle lake about 8 000
years ago
so you can see a nice aerial picture of
crater lake on the top left
and a nice picture of the caldera during
the winter on the at the bottom
and what you see on the top right is
what happened during this eruption
so we had a big volcano with a big magma
chamber beneath
and during the eruption it did not start
at the center of the volcano but rather
on the side and
triggered eruption all around
all around the summit and that led to
empty the magma chamber
therefore leaving a big void in the
crest and so
that couldn't hold the roof of the magma
chamber anymore and the roof collapsed
and like a piston more or less and so
that made a big hole that was
then filled with water and that is
creating cradle lake which is actually
the deepest
natural lake in the continental us
so why do we study volcanoes here i just
show you that
how do we do that here at the university
of oregon we've got the chance
to have a center for volcanology
meaning we've got um 11 faculties whose
richard is
whose research story is principally all
partly focused
on volcanoes and their activity and so
that can go from how do you
create magma in the crust or in the
mental how does this magma
is transported through the crust to how
it erupts at the surface and the
consequence of
its eruptions on top of having
11 faculties we've got every year more
than 20 master and phd student and we've
got also postdoc and research scientists
and something that is probably more
interesting for you we've got also a lot
of undergrads
working with us in our labs every single
year so
right now it's a bit tricky of course
with um all the situation to have people
working in a lab but in normal year i
always have two or three
person uh playing with rocks in my lab
or images
and so on so you should definitely ask
me and my colleagues about a potential
um opportunity to work in um in
our lab so in my group in particular
that you can see on the right
so it's me and and free phd student josh
carey and monsie
you can see first that the atmosphere in
our group is pretty
it's pretty fan so on top of doing uh
working hard and trying to produce good
science we also have fan remember i do
this job by patient so
i really want my student also to a fan
when they come to the lab
and they want to just come and work and
we try to
answer some very simple question in a
way
for example why and how does a volcanic
eruption start and stop
what controls the explosiveness of an
eruption whether it will be
effusive or explosive
what causes shifts from one activity to
another
and can we anticipate the continuity of
an eruption meaning
over the few hours two days to some time
months of an eruption
can we predict how it will evolve so all
together we work
on a bunch of volcanoes most of them in
in the cascades because it's really easy
to go there
it's as i said few hour drives from
eugene you can bring back
almost as many sample as you want in a
big track
it's more tricky when you when you study
a volcano that is far away and you need
to
to select which sample you take um to
go back in the plane so we work on
medicine lake uh
volcano in california newberry volcano
and crater lake here in oregon and
monsieur with costa rican actually is
working on poas and toyaba
volcano in costa rica so
how do we approach this question in
general there are many ways to
approach volcanoes remember we
can record and analyze only things we
see at the surface so
most of the processes associated with
volcanic eruption are hidden just
because
they occur in the crest so you can
either use
the deposit they leave behind so what i
do so go in the field map and describe
deposits of past eruption
collect samples and then go back in the
lab to analyze these samples collected
in the field
you can monitor these active volcanoes
or even those that are not
active or not not active at the moment
so that mainly is the role of the usgs
or you can try to reproduce processes
that you cannot see
and that happen in the crest so you can
in the lab and we've got some colleagues
here who do that
at the university of oregon they have
instruments that are able to reproduce
the condition of temperature
pressure composition and so on that
occur in the crest to study what
should happen based on what we know
another way to
also study volcano that is sometimes
standalone
approach or can be complementary to the
other approaches
is numerical modeling or theoretical
approach and so that's what you can see
on the bottom
right of um of the screen here is an
example of a numerical simulation of
what would happen
if a part of a volcano would collapse in
the sea and what kind of waves it would
produce
and so that was a study that we've done
in 2012 and actually this volcano
collapsed in 2018
and killed more than 400 people in
indonesia
so all of these approaches whichever
they are they involve a lot of numer
a lot of instrument they involve physics
math
chemistry engineering you can also of
course be interested in the social and
cultural aspect of volcanoes and that's
another area
volcano that can be studied
so i decided to focus a little bit more
to talk now
on what we can learn from an explosive
version
from the deposit it leaves behind so um
most of the past almost nine years
actually i've been working
at medicine lake volcano in california
so you can see here on the map
on the on the left that it's about four
hours drive from
eugene to the south it's a very nice
place very wild
it's not a national north state park so
um
it's pretty remote um it's hard actually
to find places to stay
around if you don't want to camp for
example and i've been focusing my work
on the last eruption of medicine lake
volcano that is about a thousand years
old
and this eruption started explosively
and released a lot of premises and you
can see
at the bottom this panoramic view of a
quarry
that is currently exploiting these
premises to make
light cement for example or light stones
and the second part
of the eruption was effusive and it led
to the emplacement of lava flows
obsidian flows
that you can see here from the aerial
view on the right of the image
so having a volcano producing both
explosive and
effusive activity is very common with
subduction volcanoes so you can see here
two pictures
on the left is mon sunderland's in 1980
so some of your parents or grandparents
if you live in the pacific northwest
probably remember this
famous eruption and on the right is also
monsante lands about 25 years later
and many of you may know that monsanto
erupted in 1980 without knowing that it
actually also erupted between 2004 and
2008
but this eruption was effusive and so of
course
less impressive less dangerous and
therefore less known
so that shows you that the single
volcano can produce very different types
of activities and you better know
which one you would have um in order to
better assess hazards and and and
mitigate risk
so um medicine lake volcano the last
eruption was
similar except that we had the two
phases during the same eruption on the
left you see again this quarry with all
the premises so very explosive
and on the right you see a closer view
of um
of the obsidian so if we take even a
closer view
of these two products you see permisses
on the left
here and obsidian on the right and to
see it even better
i brought some samples here that you you
can see so this is a premise from
a medicine lake volcano and this is an
obsidian and it might be
very surprising but these two rocks were
actually the exact same magma to begin
with
meaning it's the same chemical
composition it's the same amount of
crystal
except and you can see very clearly uh
with the camera
this one is white ish this one is
blackish this one is full
the palmis is full of tiny voids tiny
vesicles as we call them while this one
is
pretty dense and and and glassy
and actually this one is full of void
it's actually
about 75-80 percent of oil and if you
place it
in a bowl with water it actually floats
and remember
these are two products of the same
volcano during the same eruption
except two phases so how can we
um actually explain these um differences
well if you see on the cross section of
a conduit that is here on the screen in
the center
you start with the same magma at the
bottom this magma is full of
volatiles and so you know volatiles you
know carbon dioxide for example in your
soda
so this is a volatile that is actually
dissolved if you take
when you buy a bottle of soda you don't
see any bubble yet
right and it's because the gas is
dissolved
it's the same for the magma except that
most of the volatile in
in the magma is water what happened when
the magma is rising towards the surface
the pressure is decreasing
and how could you mimic that with your
bottle well decreasing the pressure
would be removing the
lid of your um of your bottle for
example if you squeeze the bottle when
it's
it's closed it's really hard if you open
it it's
more soft it's because you release
pressure so if i give you a bottle of
soda
the same bottle of soda and i shake it
and i ask you can you open it without
putting soda everywhere or can you open
it
putting soda everywhere what would you
do probably
in the first case the explosive case you
would quickly open the bottom
and that you would release the pressure
very very fast and that would lead to a
quick
exhalation of the volatile so that's
when the diesel volatiles turn into tiny
bubbles that then grow
and that rise to the surface and they do
that so quickly in the bottle of soda
that it makes
it's making an explosive eruption while
if you wanted to
um not pour soda everywhere you would
slowly open
your bottle and you you would here for
the shh of the pressure being released
and with the same initial magma in your
case
soda you could make two different types
of eruption that's exactly the same
thing with the magma
in one case on the left it's rising very
very quickly
and so um you're producing explosive
eruption
to simplify and on the right you can
erupt your magma
but in a more less explosive
way so um
to study these processes on the field we
first need sample
and so that's why we go in the field
sometimes you go in the quarry it's
really nice and easy but sometimes you
actually have to dig and so this is a
time lapse of
me and my colleague from university of
hawaii digging in the wild at medicine
lake
and so you must have seen us digging and
standing and looking at the deposit and
and um discussing whether
um what we see in the end we collect
some samples
then we turn whatever we see on the
field so
for example the picture on the left is a
section in the big quarry that i've
shown you before
and you can see that we've made some
kind of stairs
to refresh a bit the outcrop and be able
to see the different layers
and so from the picture on the left
which is about 14 meter
of deposit so 46 feet um
we turn that into a description of the
deposit in the middle
where you can see different layers based
on the size of the
class so that's how we call every tiny
rock the size of the clast
whether they are obsidian or pieces of
obsidian or pieces of premises
the proportion of premises and obsidian
and so on
so then what we do you can see all these
little arrows on the
strat column that's how we call the
picture in the middle there's some
little triangle
each triangle is a sample meaning we've
taken
so many samples throughout the explosive
deposit
because as you can see from the
description in the middle
there are layers it's not all the same
thing all the way from the bottom to the
top it changes
with time because remember here we're
looking at the deposit
so whatever was deposited first is the
beginning of the option and what was
deposited last is the end of the
eruption
so the idea is if we can look at some
properties of these rocks
from the bottom to the top we are
looking at properties of this rock
through time
and maybe we will have some indication
that at some point
towards the end of the explosive phase
this ex
this eruption will turn into something
effusive
so just from the field we've seen that
the explosive phase is not steady but
rather
like pulses uh that was one of the
main finding by dinging a lot of pits
actually i think now we are
150 pits uh dug
uh over the last few years some of them
are very tiny maybe
maybe like i don't know 10 or 15
centimeters some of them
are 14 meters as you can see here so
that requires a lot of time
we've seen also that this explosive
phase was not just
one big plume meaning a volcanic plume
but rather at least two main plumes and
so that's something nobody can tell us
because this eruption took place
about a thousand years ago and except if
you dig into the deposit
you won't be able to have any
information about this eruption
so the picture on the right here shows
you some of the sample collected
and then what we do we go back to our
lab
so in my lab we've got for example the
instrument that you can see on the top
right
and this one is used to measure the size
distribution of particles
so if you take um a sample so what i
call a sample is just not one rock but
it's rather like a big ziploc bag like a
gallon
ziploc bag worth of deposit and you've
got
rocks that are pretty big as the one i
showed you before that permis that is
now all soaked with water
and some of them are very tiny you
barely see them by
eye and the size distribution meaning
how much of the
very fine particle versus the large
particle
you have and how this size distribution
is changing with time
is um something very important that we
want to know
um that will help us to
for example say how violent was the
fragmentation mechanism so the
fragmentation is when the magma is
rising in the conduit
and remember it's one body of of liquid
with some bubbles in it
and that at fragmentation it turns into
particles solid particles which are the
rocks that i just showed you carried in
in a gas
phase and so the fragmentation mechanism
um
depending on whether um how violent it
is it will change the size distribution
of the samples
and so this instrument at the top right
is just something very easy to
understand you've got your particles
that are falling in front of a white
background
and you've got a high speed camera that
is just detecting every single particle
and turn this particle you know the
black images that you see at the
at the bottom into um into a size
then we may want to see in individual
class
like can we see bubbles can we see
bubbles like even tiny bubbles we cannot
see by
eyes to do that we go to some instrument
that we have here
on campus in camcore so it's an
underground facility with
a lot of high-tech instrument including
the two that you have on the
on the left here on the top left is
called an
electronic micro microprobe sorry so
that
tells us the chemical composition of
um of the glass or the the
crystal in the rock and the one on the
bottom left is called a scanning
electron microscope so it's just
um a fancy microscope that allows you to
see
very tiny features in your sample but
the problem with these two instruments
is that they are destructive in the
sense that you need to take your sample
and cut a slice through it and you might
lose
some information about the whole texture
of the clast
and so that's why more and more um in
in the earth sciences we try to use
non-destructive
instrument that allows us to see uh the
sample the structure of the sample in
three dimension
and we use x-ray microtomograph or x-ray
microscope
and actually we just have such
instrument a very
high-tech and expensive instrument that
arrived at
university of oregon and that will be
hosted the night campus so that's the
instrument you can see
on the top left and how does it work
you've got actually a schematic direct
diagram on the top right you just take
an x-ray if you wish of your sample like
you would take an x-ray of your chest
when you go to the doctor sometimes and
instead of taking just one you are
taking hundreds of them
while rotating your sample and itself
and using
algorithm and big computer you can
actually reconstruct the internal
structure
of your sample and this is used in many
different fields
um so if you look at the bottom left for
example you see a carbon fiber rem first
polymer composite and you can see the
scale so 100 micron scale so the
the black bond on the image on the on
the left is more or less the thickness
of one of your hair for example
in the middle you see a piece of of
concrete
with the different components of the
concrete and on the
on the bottom right you see some
pictures um
of of my sample the one that we
collected at medicine lake
and i'll show you in the next video this
sample that is labeled number three and
it's cycle in red
and this is actually the whole sample uh
seen 3d
and with this instrument you can
actually zoom in the
the sample and you can see the whole
texture of the sample so what you see
here and the video will pause for a
second you see in white
what appears in white is the solid part
of the sample so it's the glass
volcanic glass so it's more or less like
a glass you would drink in except it has
a
little bit different composition and the
dark part
is void and so um what we've done we've
passed many of this sample in this
instrument and we've we've discovered
something new
so on the next video you will um
see two samples from the same eruption
one on the left and one on the right the
one on the left is
a normal pemis something we all expected
in in our
field to see so you see big void inside
and you see like tiny void also on the
right is also another premise
but you can tell even if you have not
taken any volcanology class that it is
very different
it seems to be made of different domains
with different textures
you see also big crystal that's the
white thing that is disappearing now
and you see that the boundary between
these grays
these grains of these domains is
actually
um a bright so it means it's more
it's more dense and so that tells us um
many things about the eruption itself
new things about the eruption itself
it tells you that instead of the magma
breaking in tiny pieces and those tiny
pieces
living their own life afterwards some of
them may collide
and may agglomerate and partly sinter
making a whole new sample with zillion
of these tiny
premises so
what we have done for example and it's a
work in progress we have dismantled one
of these
samples so you can see on the left here
the 3d rendering of the sample
and with some slices and we've
we've separated the different textural
domains and we were able to make a size
distribution
of these tiny particles and as i told
you before the size distribution of the
particle can tell you
a lot of information about the
fragmentation processes
so the single process that will
differentiate
an explosive eruption from a diffusive
one so the process
you really want to understand and that
happened in the conduit and
of course that you have absolutely no
way to witness with any kind of
instrument right now at least
so these are some of the some of the
analysis we do
with the samples um that we collect on
the field
so if you're really interested in
volcanoes or
earthquake and in the pacific northwest
um
i could encourage you to consider
registering for my class
volcanoes and earthquake in the fall so
it's a 300 level class but it's actually
open to everybody from freshmen
to seniors and all disciplines sometimes
i've got freshmen in philosophy together
with
senior and geology so this class is
definitely
adapted to everybody and we'll talk
about um
things like i just said how do we form
magma how is it um
how is it um transported through the
crest why do we have earthquake in some
places and why
not in other places we'll talk about um
a lot of things and we'll take a lot of
example from the pacific northwest from
the nice kinder butte here in eugene
oregon maybe a mile from this very room
and it's actually directly related to a
volcano
or to the ghost forest that you can see
on the coast of oregon and washington
that are related to
the last big earthquake in the region
that was about
300 years ago if you want to
learn more about the societal and and
cultural aspect of volcanoes and
earthquake well as freshmen you can also
take the first-year interest group
which is pairing this class of volcanoes
and earthquake with an anthropology
class called origin of storytelling
and we'll look beyond just the science
of learning about volcanoes what we can
learn from
the traces they live buried in memory
so from from books
or letters that were written hundreds of
years ago
and so if you're interested in in
geology in general
volcanology is only a part of what we do
here in the earth sciences department at
the university
of oregon you can see that volcanology
is part of this
of this rectangle on the left but we
study also environmental
geosciences paleontology geophysics and
so on
and so this flyer is available on our
website
of the of sciences with a list of what
kind of
question we tackle what kind of job you
could get with
a career with a diploma sorry in in
geology
so in any case whether you're interested
in volcanoes earthquake or
not at all you must be interested in
something
you don't know it yet but you will
discover it hopefully in the next few
years
and i would encourage you to just stay
and be curious do not hesitate to ask
us your professors about their research
their lab their classes their interests
right now we are able to answer you
by email or by zoom it might take a
little bit more time as usual
uh compared to as usual because of the
the condition
but we are here to help you find your
way
and so with that i'll thank you and i
will give it back to korra now
thank you so much we have some time for
questions and have a few in the hopper
here
um and actually our first question comes
from julia and it sounds like she has
uh she wants some advice from you about
something
sort of semi-related julia says i am
learning french and i'm very interested
in environmental studies
in an international sense would you say
there are good opportunities in france
to study sustainable practices
and which natural areas in france would
you recommend visiting
so yes i mean environment is something
worldwide it's not just in the us
but as i tend to
learn with my colleagues working in
environment is that environment is
really related to policies and these
policies might change a lot
here in in the us you've got like the
city level the county level the state
level the federal level
in france it's different you've got the
french level like the
the the country of france but then
you've got the european level and
everything is changing so if you're
interested in like the
science of environment that's one thing
yes there are definitely opportunity
opportunities in france since it's not
my discipline and i left france almost
nine years ago
i wouldn't be the best person to direct
you to a particular university
but then if you want to visit france
there are so many places it's such a
nice
it's just such a nice country we've got
the mountain we've got the
forest we've got the countryside we've
got big cities you of course know we've
got a lot of history and culture that i
really miss because this year i was not
able to go back to france i as you
usually do and see the families and and
so it's
really sad for me this year but yes we
really enjoy going back to france every
every year and so please email me with
more questions about france if you want
and i'd be pleased to
take time if i find it to answer your
question
thank you for that um so we have some
more related to uh volcanology here
um one of the questions that we have is
do the eruption deposits you've studied
uh like say in in medicine lake offer
any predictability to the size and scope
of
future eruptions of stratovolcanoes in
the pacific northwest
that would help communities prepare
absolutely imagine you're a
volcanologist anywhere in the world
and you're in charge of studying this
volcano that hasn't been erupted in
like at least that anyone can remember
at least two or three hundred years ago
what do you do
how do you know how affinity wraps how
do you do how do you know
whether it erupts explosively or
effusively well you look at past
eruption so you dig into the deposits
and so there's a whole part that i
didn't talk about which is dating a
product of an eruption so i know
i'm not the first one to study that
particular eruption so i know it's about
a thousand years old
but if i was the first one to study it
i would have need to date it and so
if you do that very carefully for one
volcano you can go back in time and you
can start to build
a frequency meaning you know that this
volcano
is erupting almost every 100 year with
small eruption but
once in a millennium it's erupting a
very very big eruption that can cover
the whole region and impact so now it
could impact
um not only people on the ground but
think about also aviation for example
um 2010 a javier cello cooled in iceland
just shut down the whole european
aviation for
more than a week i was taking that so i
can tell you about that
and it was a very modest eruption um in
terms of
didn't kill anybody as far as i know and
and yet
like billions and billions of of um of
impact so yes studying eruption
how they occurred and also how
frequently and where
and what type of deposit they make and
you've seen
some images that i've shown you but some
eruptions just make
lava flows and they are nice you can
actually i've i mean i played with magma
in the lava flow and i was not crazy
many people do that even people who are
not scientists
it's not that dangerous if you know what
to expect and and there are of course
some volcanoes and some eruptions you
don't want to stay
close by so yes studying
eruption like studying earthquake will
help you
understand the frequency and the size of
these events
and it won't tell you that monsanto lens
will erupt
june 12 2025 for example it won't tell
you that
but it will tell you that monsanto lens
is the one
volcano in the cascade right now that is
erupting them more frequently and if you
ask
any of the usgs scientists in charge of
volcanoes in the
in the cascade most of them would tell
you that they would bet the next one to
erupt is again monster lands
maybe an effusive eruption like from
2004 to 2008
or maybe an explosive one like 90 80.
well it's pressed eruptions tell us how
big the next one will be like how much
damage it will do to the surrounding
area or
not not directly not directly but uh
but an eruption that is explosive the
eruption i'm studying
uh for example newberry last eruption
that was also about a thousand years ago
sent ash down to idaho the last eruption
of yellowstone it was almost everywhere
in the continental us
so it's like different magnitude of of
eruption
and you don't know that if you don't
study the deposit and also
whether it formed the caldera for
example crater lake crater lake was 50
times larger than monster lands 1980 for
example
and was like at least 50 times less
large than the last eruption
of yellowstone that's amazing um
one of the things that i was reading
just the other day was actually some
a news story about some work that
one of your colleagues has done a phd
student here in earth sciences has done
around studying the cascade network
what do you know about that research
that dan o'hara has
has published recently and what does
that tell us does it inform the work
that you're doing
so dan has been looking as far as i know
and i still need to read this paper just
that just came out and that he published
he looked at the morphologies of of of
volcanoes and not only the big one that
most of you know and that were uploaded
on my map
a few minutes ago but also all these
tiny satellite vents
for example if you look at newberry
volcano it's actually
the second largest volcano in the
cascades and nobody would know because
it's very flat and chill shape
but it has at least 400 vents
400 tiny volcanoes that are on top of
this big volcano and each of this
volcano produced an eruption
most of them were very tiny with a small
lava flow
but some of them were probably larger so
he studied all of these
um all of these volcanoes their shape
and of course because it went back in
time much further than
i went i'm usually studying very recent
eruption it might be
something weird for you when i said my
eruption is like a thousand years old
but it's still quite young the deposit
is still quite fresh
it was studying eruptions that were like
millions years old
and so of course in millions of years
you have um not only geological events
but also you've got a lot of erosion so
he had to go back in time and correct
for that
and he was trying to as i remember
predict some kind of pattern in terms of
frequency of eruption
but on much longer time scale so with
less resolution
if you wish like less precision and
accuracy because it just cannot do that
because it's left with whatever is
available on the field of course
but it went much further back so that's
one of the very cool thing of our
cluster
is that he can talk to me i can talk to
him we understand each other
we can be complementary and yet we do
things that are very different
and that is something that you may
discover when you come to
to the you or you go to college is that
it's really rare in the us at least to
have a group of scientists studying the
same
topic the same object whether it's
volcano
anything else without overlapping too
much so we don't do exactly the same
thing
but yet being able to to talk to one
another and tackle very big questions or
very big
grants if you wish um together
thank you for that um okay so this is
the last question you talked a little
bit about the classes that
students can take from you there's
another question in here
are are uo students able to study how
communities prepare for
and recover from volcanic eruptions and
other natural disasters
yes yes so um one thing we do in that
class
and we were supposed to do that for
example in the spring before we were
you know with what happened we couldn't
go we go to cascade volcano observatory
so cascade volcano observatory is in
vancouver washington so right next to
portland
and it um is where the usgs
folks are actually monitoring our
volcano so you go for example in a room
that is full of monitors with
seismometers from all the different
volcanoes
and they are the people who will issue a
warning for example for aviation and so
on
and they work together with many
different organizations
an institution across the u.s for
example
whenever you want to monitor a volcano
you need to put instrument
where do you put this instrument is it
like a brew of land management
is it a national forest site is private
land so you need to discuss with
different actors
if there's a disaster then it's female
is taking the lead
but fema doesn't doesn't take the lead
until there is a disaster
and so it's always working with all
these groups and so
um even though we worked a little bit
on that topics um on these topics um
here in the cluster at the university of
oregon
um our colleagues at cv are more
knowledgeable about all these questions
and so that's why
more and more we try to not only us but
also our student
and undergraduate student for classes
have connection with this
um with these folks at cascade volcano
observatory
or um for earthquakes for for example
thank you so much that is all the time
that we have for questions
again for you students please log on to
community.uoregon.edu to complete your
reflection of this program
it's also worth noting that we're at a
critical point in the summer where you
will begin to
get more and more information from
various departments on campus
it's really important that you continue
to check your at you oregon email
account and read those emails
with attention all of the emails that
we're sending you in the coming days and
weeks will have a call to action for you
and taking action on these will be cr
will be critical for your readiness for
the fall
for questions about this or any other
IntroDUCKtion program you can go to our
website
orientation.uoregon.edu you can email us
your questions at orientation@uoregon.edu or you can text those
questions to us at 541-346-1159
thanks to you students who are watching
us live today thank you for your time
and to you Dr. Giachettii thank you so
much for helping our new ducks get ready
for fall
you're welcome
you
