WEBVTT

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OK. Hello, everyone. Welcome to
today's seminar Wednesday, March

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15th.

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Uh, everyone at home, please
turn off your cameras and your

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microphones.

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Just a couple quick
announcements today. There is a

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happy hour at 4:00 o'clock this
afternoon at the space bar.

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That I'd sadly won't make it to,
but if anyone's on campus,

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please join the crew that's
gonna walk over there for the

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happy hour.

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Tomorrow morning, there's the
not ready for prime time. Crew

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00:01:01.241 --> 00:01:04.885
is meeting at 10:00 AM in the
Yosemite Room where I think Tim

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Clements is going to present
something, so get in touch with

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Tim. I think is the contact for
that if you're not on the

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mailing list for that.

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Next week at 9:00 AM Pacific
Time, Catherine Paterno's giving

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a talk.

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For the geologic Hazard Science
Center that's going to be on

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teams.

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Uh. And then on March 30th,
there's going to be that's a

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Thursday. There's going to be
all hands.

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That meeting, which is on teams
as well.

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And now I'm going to turn it
over to Catherine to introduce

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the speaker.

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All right. It's a great pleasure
today to introduce Paula Bergey

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Please.

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today. Can you hear me?

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Yes.

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OK.

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Paula was an undergrad at Smith
College in Massachusetts. She

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was then a research assistant at
the Earth Observatory of

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Singapore for 2 years where she
worked with Judith Hubbard on

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the geometry of the Dicom, Mont.

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Beneath Bangladesh and also on
the geometry of the thrust

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faulting in the Himalayas
surrounding the Nepal earthquake

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in 2015.

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She got her PhD in Insar type
studies at Cornell with Rowena

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Lohman. She worked on insar
detection of soil moisture and

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forest disturbances. So these
are basically signals that are

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doppelgangers with deformation.
They're not deformation, but

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they are doppelgangers. And
since 2021, she's been amended.

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Hall in Golden, Co at the in the
landslides project and the

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ground failure Mapping project,
it's great to have her here. She

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also gives great talks.

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So I'm really glad to to to see
Paul here and take it away.

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Paula.

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Great. Thank you so much,
Catherine. I appreciate the the

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introduction and I feel like you
put the, the the bar high so

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high deliver. Alright. Thank you
everyone for being here

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physically and online.

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So my talk today is about these
weird hexagonal features that

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you can see in this image, and I
walked into the earthquake

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Science Center and of course all
the walls are covered with

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hexagonal paintings. So like
this is perfect. They just

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follow me everybody sessions so
feels fitting.

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OK. So yeah, so during my
Mendenhall, I've been working

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with the earthquake triggered
ground failure team, which I

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will talk a little more about
what exactly that is in a bit.

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But specifically with earthquake
triggered liquefaction. So these

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are features that we thought
initially were liquefaction, but

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it turns out that they probably
aren't.

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And that is why I'm calling them
liquid fiction. Liquid fiction

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is not a real thing. It's
something I just thought was

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funny and made-up. So that was
why this talk is called faction

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or Liquefaction.

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I first just want to quickly
acknowledge collaborators, so

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most people at the USGS, Eric
and Kate, are both part of they

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run the earthquake triggered
ground failure model then and

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Sean are both geotech people
that helped with the kind of

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teaching me about liquefaction
and interpreting some of the the

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Geotech data. And Kyle was
actually one of my old lab

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banks, and he's been really
helpful with looking at some of

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the insar stuff that I've been
doing.

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OK, OK, so before.

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I get into to everything. I
think it's important that we're

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all on the same page about what
is liquefaction.

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Uh, so it's essentially, it
sounds to me it sounded like

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fake, but it's very much real
real thing.

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It's essentially when the ground
goes from a solid to a liquid or

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acts like a liquid, and it does
that during earthquakes so.

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What you need the the kind of
ingredients you need to create a

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situation in which liquefaction
is likely to occur is sand sized

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particles. It could be a little
silty, but the dominant size is

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sand. They have to be kind of
loosely packed and water

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saturated.

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So during an earthquake, the
fact that they're loosely packed

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means they can kind of
reconfigure into a denser

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configuration, and what that
means is that the stress or the

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kind of effective pressure is
transferred from the contacts of

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the particles to the surrounding
water. Therefore the ground

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turns into a liquid.

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So the results of liquefaction
are often water and sand being

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ejected onto the surface. As you
can see here, this is surface

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ejecta. This is kind of, I think
the most common feature that

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people think of when they think
of liquefaction is sand boils.

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So I just wanna make it clear
right now that.

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Liquefaction the way that I'm
defining it is a mechanism,

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right? It's how stuff the the
reason why things were ejected

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onto the surface. The actual
observation is this surface

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ejecta, which I think is most
commonly assumed to be because

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of liquefaction. But as we will
discuss, there could be other

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mechanisms to to have the same
kind of observation.

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So this is just an example. If
you've never seen what

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liquefaction looks like.

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Here is the things I mentioned
before sand boils so they look

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00:06:43.720 --> 00:06:47.806
sort of like tiny volcanoes and
this is from the Christchurch

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00:06:47.806 --> 00:06:52.155
earthquake in 2011. There's also
a bunch of just kind of standing

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00:06:52.155 --> 00:06:56.307
water that was ejected out of
the subsurface along with all of

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00:06:56.307 --> 00:06:57.625
that sand. So it is.

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Really, actually not. Not great
for infrastructure, it's one of

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00:07:03.040 --> 00:07:06.005
the the main causes for
infrastructure damage and

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00:07:06.005 --> 00:07:09.741
collapse in susceptible areas
from earthquakes. So that's sort

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00:07:09.741 --> 00:07:11.165
of why we care about it.

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So next, how do we study
liquefaction?

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I'm sure that I'm missing a
bunch of stuff here, but this

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00:07:23.288 --> 00:07:27.181
was sort of my, uh, vague
collection or idea of what? How

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00:07:27.181 --> 00:07:31.275
people study liquefaction. So
there's geology, which is kind

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00:07:31.275 --> 00:07:35.504
of mapping and some modeling,
payless, seismology, things like

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that, remote sensing you can do
change detection with pre and

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post imagery via optical or
insar.

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00:07:42.435 --> 00:07:46.035
Umm, throught sensing datasets
are also used as proxies for

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where we think ground failure
will happen and then the geotech

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world and geotechnical
engineering are probably the

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folks that have done the most
with actually studying

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liquefaction.

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In a very detailed way. So
there's tons of lab based

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00:08:01.202 --> 00:08:02.745
studies going back decades.

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00:08:03.625 --> 00:08:07.051
It focuses on soil mechanics.
You actually do testing, like in

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00:08:07.051 --> 00:08:10.205
the field penetration tests,
which I'll talk about later.

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00:08:11.425 --> 00:08:16.675
I maybe ohh the color does not
look great there these.

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00:08:18.065 --> 00:08:21.724
I'll just turn this. You can see
that there's different colors

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00:08:21.724 --> 00:08:22.015
here.

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I guess now the sports the room,
but.

51126870-83bf-4ff6-a279-31b8662b379e/1192-0
00:08:27.795 --> 00:08:30.535
I can get that. Yeah. OK, so.

51126870-83bf-4ff6-a279-31b8662b379e/1278-0
00:08:31.325 --> 00:08:35.313
I might have over thought this a
little bit, but this is sort of

51126870-83bf-4ff6-a279-31b8662b379e/1278-1
00:08:35.313 --> 00:08:38.566
how I put it together in my
head, so there's kind of

51126870-83bf-4ff6-a279-31b8662b379e/1278-2
00:08:38.566 --> 00:08:42.309
different ways you can study
things spatially, like imagery,

51126870-83bf-4ff6-a279-31b8662b379e/1278-3
00:08:42.309 --> 00:08:46.175
right, temporally, like time,
Siri, time series, or going down

51126870-83bf-4ff6-a279-31b8662b379e/1278-4
00:08:46.175 --> 00:08:49.796
into the subsurface right, like
actually looking at what's

51126870-83bf-4ff6-a279-31b8662b379e/1278-5
00:08:49.796 --> 00:08:53.785
happening underneath the ground.
And this is sort of how I broke

51126870-83bf-4ff6-a279-31b8662b379e/1278-6
00:08:53.785 --> 00:08:57.651
things up. So geology focuses
mainly on subsurface and spatial

51126870-83bf-4ff6-a279-31b8662b379e/1278-7
00:08:57.651 --> 00:09:01.395
analysis, remote sensing mostly
on temporal and spatial and.

51126870-83bf-4ff6-a279-31b8662b379e/1297-0
00:09:01.475 --> 00:09:05.645
Geotech, mostly on subsurface
and temporal, and I've kind of

51126870-83bf-4ff6-a279-31b8662b379e/1297-1
00:09:05.645 --> 00:09:08.995
tried to bring all of these
things together and.

51126870-83bf-4ff6-a279-31b8662b379e/1322-0
00:09:10.805 --> 00:09:14.802
Made some sort of coherent story
about or informed kind of this

51126870-83bf-4ff6-a279-31b8662b379e/1322-1
00:09:14.802 --> 00:09:18.425
work using all three of these
things. All three of these.

51126870-83bf-4ff6-a279-31b8662b379e/1331-0
00:09:19.155 --> 00:09:21.865
Methods and, UM, all three of
these.

51126870-83bf-4ff6-a279-31b8662b379e/1337-0
00:09:24.085 --> 00:09:26.035
Parameters parameter space I
guess.

51126870-83bf-4ff6-a279-31b8662b379e/1339-0
00:09:27.355 --> 00:09:27.685
Alright.

51126870-83bf-4ff6-a279-31b8662b379e/1348-0
00:09:29.065 --> 00:09:32.235
So let's talk about how the
USGS.

51126870-83bf-4ff6-a279-31b8662b379e/1377-0
00:09:32.825 --> 00:09:37.364
Studies ground failure from
earthquakes. So there's, I mean,

51126870-83bf-4ff6-a279-31b8662b379e/1377-1
00:09:37.364 --> 00:09:41.904
a lot of groups do this, but my
specific group models ground

51126870-83bf-4ff6-a279-31b8662b379e/1377-2
00:09:41.904 --> 00:09:45.700
failure triggered by
earthquakes. And the way that

51126870-83bf-4ff6-a279-31b8662b379e/1377-3
00:09:45.700 --> 00:09:47.635
our group defines defines.

51126870-83bf-4ff6-a279-31b8662b379e/1430-0
00:09:49.495 --> 00:09:52.685
Earthquake triggered ground
failure is A1, model is for

51126870-83bf-4ff6-a279-31b8662b379e/1430-1
00:09:52.685 --> 00:09:55.990
landslides, the other is for
liquefaction. I will only be

51126870-83bf-4ff6-a279-31b8662b379e/1430-2
00:09:55.990 --> 00:09:59.523
focusing on the liquefaction
stuff, but I think this might be

51126870-83bf-4ff6-a279-31b8662b379e/1430-3
00:09:59.523 --> 00:10:02.657
useful for those of you who
don't know much about this

51126870-83bf-4ff6-a279-31b8662b379e/1430-4
00:10:02.657 --> 00:10:06.190
model. I'm just gonna. I'm gonna
show you how. Like what goes

51126870-83bf-4ff6-a279-31b8662b379e/1430-5
00:10:06.190 --> 00:10:07.615
into it and how it works.

51126870-83bf-4ff6-a279-31b8662b379e/1437-0
00:10:09.295 --> 00:10:12.655
So here's just an example
earthquake that I pulled.

51126870-83bf-4ff6-a279-31b8662b379e/1456-0
00:10:13.345 --> 00:10:17.573
Uh, and this is the the
earthquake event page. I think

51126870-83bf-4ff6-a279-31b8662b379e/1456-1
00:10:17.573 --> 00:10:20.495
most most of us are familiar
with it.

51126870-83bf-4ff6-a279-31b8662b379e/1536-0
00:10:21.705 --> 00:10:26.097
So we have our, you know, shake
map. Did you feel it, pager? And

51126870-83bf-4ff6-a279-31b8662b379e/1536-1
00:10:26.097 --> 00:10:29.950
then one of those widgets is
this ground failure product

51126870-83bf-4ff6-a279-31b8662b379e/1536-2
00:10:29.950 --> 00:10:34.207
which I show here. So this is
what it actually looks like here

51126870-83bf-4ff6-a279-31b8662b379e/1536-3
00:10:34.207 --> 00:10:38.330
shaking intensity contours here
is the probability of ground

51126870-83bf-4ff6-a279-31b8662b379e/1536-4
00:10:38.330 --> 00:10:41.979
failure. You can see the scale
down here. This is for

51126870-83bf-4ff6-a279-31b8662b379e/1536-5
00:10:41.979 --> 00:10:46.237
landslides and this is for like
what faction. So again this is

51126870-83bf-4ff6-a279-31b8662b379e/1536-6
00:10:46.237 --> 00:10:50.022
the model that I will be
focusing on. But I think right

51126870-83bf-4ff6-a279-31b8662b379e/1536-7
00:10:50.022 --> 00:10:52.455
off the bat you can see
landslides.

51126870-83bf-4ff6-a279-31b8662b379e/1554-0
00:10:52.815 --> 00:10:55.421
No surprise, I mostly in
mountainous regions,

51126870-83bf-4ff6-a279-31b8662b379e/1554-1
00:10:55.421 --> 00:10:59.105
liquefaction tends to happen in
flat regions near coasts, right.

51126870-83bf-4ff6-a279-31b8662b379e/1600-0
00:11:00.605 --> 00:11:04.755
So what actually goes into this
product is predictive variables

51126870-83bf-4ff6-a279-31b8662b379e/1600-1
00:11:04.755 --> 00:11:08.775
and liquefaction inventories. So
the predictive variables are

51126870-83bf-4ff6-a279-31b8662b379e/1600-2
00:11:08.775 --> 00:11:12.536
listed here. The static ones we
have and these are global

51126870-83bf-4ff6-a279-31b8662b379e/1600-3
00:11:12.536 --> 00:11:16.232
variables, right? This is
something that we do for every

51126870-83bf-4ff6-a279-31b8662b379e/1600-4
00:11:16.232 --> 00:11:20.187
earthquakes all over the world
as long as there are above us

51126870-83bf-4ff6-a279-31b8662b379e/1600-5
00:11:20.187 --> 00:11:21.355
certain magnitude.

51126870-83bf-4ff6-a279-31b8662b379e/1609-0
00:11:22.295 --> 00:11:25.835
So we have the S 30 mean annual
precipitation.

51126870-83bf-4ff6-a279-31b8662b379e/1615-0
00:11:27.045 --> 00:11:28.955
Distance from a coast.

51126870-83bf-4ff6-a279-31b8662b379e/1627-0
00:11:30.005 --> 00:11:33.775
Distance from rivers and water
table depth.

51126870-83bf-4ff6-a279-31b8662b379e/1654-0
00:11:34.875 --> 00:11:38.659
And then for you, we also input
the peak ground velocity, but

51126870-83bf-4ff6-a279-31b8662b379e/1654-1
00:11:38.659 --> 00:11:42.443
that's earthquake specific. So
that's the only parameter that

51126870-83bf-4ff6-a279-31b8662b379e/1654-2
00:11:42.443 --> 00:11:44.885
kind of changes earthquake,
earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/1675-0
00:11:46.275 --> 00:11:49.936
And then the other thing that
goes into this is, uh,

51126870-83bf-4ff6-a279-31b8662b379e/1675-1
00:11:49.936 --> 00:11:53.115
liquefaction inventories. So
there have been.

51126870-83bf-4ff6-a279-31b8662b379e/1691-0
00:11:53.515 --> 00:11:58.704
And so these are just points in
space where there have been

51126870-83bf-4ff6-a279-31b8662b379e/1691-1
00:11:58.704 --> 00:12:01.385
liquefaction has been observed.

51126870-83bf-4ff6-a279-31b8662b379e/1698-0
00:12:02.955 --> 00:12:04.705
As a result of an earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/1731-0
00:12:05.395 --> 00:12:08.822
There's about a little over
100,000 liquefaction

51126870-83bf-4ff6-a279-31b8662b379e/1731-1
00:12:08.822 --> 00:12:13.229
observations. There's also non
liquefaction observations and I

51126870-83bf-4ff6-a279-31b8662b379e/1731-2
00:12:13.229 --> 00:12:17.496
put that in quotation marks
because the non loop with action

51126870-83bf-4ff6-a279-31b8662b379e/1731-3
00:12:17.496 --> 00:12:19.665
observations are actually just.

51126870-83bf-4ff6-a279-31b8662b379e/1743-0
00:12:21.135 --> 00:12:25.675
A grid of points around where
liquefaction was observed.

51126870-83bf-4ff6-a279-31b8662b379e/1753-0
00:12:26.875 --> 00:12:29.705
And are assumed to have no loop
affection.

51126870-83bf-4ff6-a279-31b8662b379e/1755-0
00:12:31.285 --> 00:12:31.615
Alright.

51126870-83bf-4ff6-a279-31b8662b379e/1797-0
00:12:33.335 --> 00:12:37.757
We all on board? Yeah. OK,
great. So the actual model is

51126870-83bf-4ff6-a279-31b8662b379e/1797-1
00:12:37.757 --> 00:12:42.490
just a pretty basic logistic
regression model where you have

51126870-83bf-4ff6-a279-31b8662b379e/1797-2
00:12:42.490 --> 00:12:47.611
your predictive variable. I just
put an example of VS 30 here and

51126870-83bf-4ff6-a279-31b8662b379e/1797-3
00:12:47.611 --> 00:12:48.775
whether or not.

51126870-83bf-4ff6-a279-31b8662b379e/1846-0
00:12:49.145 --> 00:12:53.602
A liquefaction was observed at
in that pixel right in that that

51126870-83bf-4ff6-a279-31b8662b379e/1846-1
00:12:53.602 --> 00:12:58.130
pixel contains that point. Let's
actually inventory and then all

51126870-83bf-4ff6-a279-31b8662b379e/1846-2
00:12:58.130 --> 00:13:02.518
those predictive variables have
values for that for that pixel

51126870-83bf-4ff6-a279-31b8662b379e/1846-3
00:13:02.518 --> 00:13:06.906
to take all of those, you put
them together and voila, you can

51126870-83bf-4ff6-a279-31b8662b379e/1846-4
00:13:06.906 --> 00:13:11.225
now predict for every point on
the Earth's surface, like how.

51126870-83bf-4ff6-a279-31b8662b379e/1858-0
00:13:12.095 --> 00:13:15.217
What's the likelihood of of gun
failure? And in this case look

51126870-83bf-4ff6-a279-31b8662b379e/1858-1
00:13:15.217 --> 00:13:15.465
back?

51126870-83bf-4ff6-a279-31b8662b379e/1870-0
00:13:18.015 --> 00:13:22.066
All right. So as with all
models, there are some issues

51126870-83bf-4ff6-a279-31b8662b379e/1870-1
00:13:22.066 --> 00:13:22.645
with it.

51126870-83bf-4ff6-a279-31b8662b379e/1917-0
00:13:23.975 --> 00:13:28.525
On the predictive variable side,
there's a because all of these

51126870-83bf-4ff6-a279-31b8662b379e/1917-1
00:13:28.525 --> 00:13:32.579
variables have to be global,
there's a lack of accuracy,

51126870-83bf-4ff6-a279-31b8662b379e/1917-2
00:13:32.579 --> 00:13:36.703
accuracy, and resolution for
everything, and there's also

51126870-83bf-4ff6-a279-31b8662b379e/1917-3
00:13:36.703 --> 00:13:40.898
other potential predictor
variables that are not currently

51126870-83bf-4ff6-a279-31b8662b379e/1917-4
00:13:40.898 --> 00:13:45.236
included in the data set. So one
example is, so I'm not sure

51126870-83bf-4ff6-a279-31b8662b379e/1917-5
00:13:45.236 --> 00:13:47.725
which you would think you know
if.

51126870-83bf-4ff6-a279-31b8662b379e/1941-0
00:13:48.425 --> 00:13:51.464
The subsurface has to be
saturated with water, so

51126870-83bf-4ff6-a279-31b8662b379e/1941-1
00:13:51.464 --> 00:13:54.929
moisture might be a good
predictor of where liquefaction

51126870-83bf-4ff6-a279-31b8662b379e/1941-2
00:13:54.929 --> 00:13:55.355
occurs.

51126870-83bf-4ff6-a279-31b8662b379e/1952-0
00:13:56.875 --> 00:14:00.425
In terms of the liquefaction
inventory side.

51126870-83bf-4ff6-a279-31b8662b379e/1987-0
00:14:02.105 --> 00:14:06.104
It's actually very hard to have
a complete inventory of every

51126870-83bf-4ff6-a279-31b8662b379e/1987-1
00:14:06.104 --> 00:14:09.974
single place that experience
liquefaction because it's just

51126870-83bf-4ff6-a279-31b8662b379e/1987-2
00:14:09.974 --> 00:14:13.908
physically hard to get to every
place around, especially for

51126870-83bf-4ff6-a279-31b8662b379e/1987-3
00:14:13.908 --> 00:14:15.715
bigger earthquakes and also.

51126870-83bf-4ff6-a279-31b8662b379e/2040-0
00:14:17.375 --> 00:14:20.531
It's most people doing these
kind of going out in the field

51126870-83bf-4ff6-a279-31b8662b379e/2040-1
00:14:20.531 --> 00:14:23.740
and collecting the data aren't
saying every time they take a

51126870-83bf-4ff6-a279-31b8662b379e/2040-2
00:14:23.740 --> 00:14:27.002
step, they're like, OK, got a
mark this as a non liquefaction

51126870-83bf-4ff6-a279-31b8662b379e/2040-3
00:14:27.002 --> 00:14:30.264
point, right? They're really
only caring about where there is

51126870-83bf-4ff6-a279-31b8662b379e/2040-4
00:14:30.264 --> 00:14:33.105
liquefaction and we actually
need both for the model.

51126870-83bf-4ff6-a279-31b8662b379e/2043-0
00:14:33.945 --> 00:14:34.635
Thanks.

51126870-83bf-4ff6-a279-31b8662b379e/2075-0
00:14:36.855 --> 00:14:41.071
So how do we improve it for the
predictive variables? You should

51126870-83bf-4ff6-a279-31b8662b379e/2075-1
00:14:41.071 --> 00:14:44.768
have some new variables, right?
And for the liquefaction

51126870-83bf-4ff6-a279-31b8662b379e/2075-2
00:14:44.768 --> 00:14:48.725
inventory, we need to either add
to the inventory, but also.

51126870-83bf-4ff6-a279-31b8662b379e/2091-0
00:14:50.495 --> 00:14:54.049
Make sure that the data in the
inventory is correct and that is

51126870-83bf-4ff6-a279-31b8662b379e/2091-1
00:14:54.049 --> 00:14:55.605
a point I will come back to.

51126870-83bf-4ff6-a279-31b8662b379e/2150-0
00:14:57.165 --> 00:14:59.904
So that is the reason why I
ended up looking at the

51126870-83bf-4ff6-a279-31b8662b379e/2150-1
00:14:59.904 --> 00:15:03.275
Ridgecrest earthquake in the 1st
place, which will be the focus

51126870-83bf-4ff6-a279-31b8662b379e/2150-2
00:15:03.275 --> 00:15:06.646
of the rest of this talk because
it's a great candidate to test

51126870-83bf-4ff6-a279-31b8662b379e/2150-3
00:15:06.646 --> 00:15:09.754
out new predictive variables.
There's a lot of data that's

51126870-83bf-4ff6-a279-31b8662b379e/2150-4
00:15:09.754 --> 00:15:13.019
available from that earthquake,
and it's currently not in the

51126870-83bf-4ff6-a279-31b8662b379e/2150-5
00:15:13.019 --> 00:15:16.075
liquefaction inventory. So I was
seeing if it was a good.

51126870-83bf-4ff6-a279-31b8662b379e/2155-0
00:15:17.215 --> 00:15:19.105
Candidate as to to.

51126870-83bf-4ff6-a279-31b8662b379e/2161-0
00:15:20.145 --> 00:15:21.595
At the then the story.

51126870-83bf-4ff6-a279-31b8662b379e/2174-0
00:15:22.815 --> 00:15:25.825
That's not what I did at all.
Like even a little bit.

51126870-83bf-4ff6-a279-31b8662b379e/2185-0
00:15:26.825 --> 00:15:29.725
So this is where we just, like,
go on a wild goose chase.

51126870-83bf-4ff6-a279-31b8662b379e/2187-0
00:15:30.725 --> 00:15:31.545
And.

51126870-83bf-4ff6-a279-31b8662b379e/2195-0
00:15:33.325 --> 00:15:36.445
Uh, yeah, you'll see. So.

51126870-83bf-4ff6-a279-31b8662b379e/2250-0
00:15:38.325 --> 00:15:42.706
We did it start with the rustic
right, so we. So here's the the

51126870-83bf-4ff6-a279-31b8662b379e/2250-1
00:15:42.706 --> 00:15:47.020
fault. Rupture is shown in red
shake map contours are shown in

51126870-83bf-4ff6-a279-31b8662b379e/2250-2
00:15:47.020 --> 00:15:51.059
yellow to green and then the
liquefaction probability that

51126870-83bf-4ff6-a279-31b8662b379e/2250-3
00:15:51.059 --> 00:15:55.441
ground failure model that I was
just talking about that's shown

51126870-83bf-4ff6-a279-31b8662b379e/2250-4
00:15:55.441 --> 00:15:57.085
as these two blobs here.

51126870-83bf-4ff6-a279-31b8662b379e/2266-0
00:15:58.885 --> 00:16:03.907
So I ended up looking mostly at
Serials Lake here and this is an

51126870-83bf-4ff6-a279-31b8662b379e/2266-1
00:16:03.907 --> 00:16:06.225
optical image of the lake bed.

51126870-83bf-4ff6-a279-31b8662b379e/2278-0
00:16:06.945 --> 00:16:09.685
It's a dry lake bed, mostly dry
lake bed flya.

51126870-83bf-4ff6-a279-31b8662b379e/2282-0
00:16:10.665 --> 00:16:12.375
And you can see.

51126870-83bf-4ff6-a279-31b8662b379e/2320-0
00:16:13.255 --> 00:16:17.437
God's not the best there, but
people really have messed it,

51126870-83bf-4ff6-a279-31b8662b379e/2320-1
00:16:17.437 --> 00:16:21.759
right? There's a lot of stuff
going on and what's going on is

51126870-83bf-4ff6-a279-31b8662b379e/2320-2
00:16:21.759 --> 00:16:25.941
mining. This is a basin that's
filled mostly with evaporate

51126870-83bf-4ff6-a279-31b8662b379e/2320-3
00:16:25.941 --> 00:16:29.775
minerals, and it's mined for
those evaporate minerals.

51126870-83bf-4ff6-a279-31b8662b379e/2335-0
00:16:31.375 --> 00:16:36.234
This is just a DM for context,
mostly flat, some local

51126870-83bf-4ff6-a279-31b8662b379e/2335-1
00:16:36.234 --> 00:16:37.295
depressions.

51126870-83bf-4ff6-a279-31b8662b379e/2340-0
00:16:38.125 --> 00:16:40.475
And here is our.

51126870-83bf-4ff6-a279-31b8662b379e/2351-0
00:16:42.115 --> 00:16:46.565
Change detection map showing
where surface ejecta was.

51126870-83bf-4ff6-a279-31b8662b379e/2365-0
00:16:46.645 --> 00:16:52.018
Umm. A manifested on the surface
from the Ridgecrest earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/2365-1
00:16:52.018 --> 00:16:53.755
There's a lot, right?

51126870-83bf-4ff6-a279-31b8662b379e/2398-0
00:16:54.925 --> 00:16:58.615
If you're curious about how this
is made, it was extremely

51126870-83bf-4ff6-a279-31b8662b379e/2398-1
00:16:58.615 --> 00:17:02.430
simple. I'll show you. I'm just
gonna show you a few optical

51126870-83bf-4ff6-a279-31b8662b379e/2398-2
00:17:02.430 --> 00:17:06.432
images before the earthquake. So
this is 28 days before 18 days

51126870-83bf-4ff6-a279-31b8662b379e/2398-3
00:17:06.432 --> 00:17:09.435
before, 8 days before, and then
two days after.

51126870-83bf-4ff6-a279-31b8662b379e/2402-0
00:17:10.605 --> 00:17:11.395
You see like.

51126870-83bf-4ff6-a279-31b8662b379e/2462-0
00:17:12.785 --> 00:17:16.649
Like it's very obvious, like you
really just have to difference

51126870-83bf-4ff6-a279-31b8662b379e/2462-1
00:17:16.649 --> 00:17:20.333
the images and like choose a
threshold. So that's how we got

51126870-83bf-4ff6-a279-31b8662b379e/2462-2
00:17:20.333 --> 00:17:23.956
this kind of optical change
detection map. There was really

51126870-83bf-4ff6-a279-31b8662b379e/2462-3
00:17:23.956 --> 00:17:27.640
nothing else that would have
caused that change in that time

51126870-83bf-4ff6-a279-31b8662b379e/2462-4
00:17:27.640 --> 00:17:31.565
period. We looked at a bunch of
variables and it's it was really

51126870-83bf-4ff6-a279-31b8662b379e/2462-5
00:17:31.565 --> 00:17:33.075
caused by the earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/2467-0
00:17:34.115 --> 00:17:35.705
So if we look at some data.

51126870-83bf-4ff6-a279-31b8662b379e/2529-0
00:17:37.275 --> 00:17:42.016
Uh, some details from some of
the areas that saw this surface

51126870-83bf-4ff6-a279-31b8662b379e/2529-1
00:17:42.016 --> 00:17:46.987
ejecta from from the Ridgecrest
earthquake. We can see this area

51126870-83bf-4ff6-a279-31b8662b379e/2529-2
00:17:46.987 --> 00:17:51.729
down here is actually one of the
very few places a field team

51126870-83bf-4ff6-a279-31b8662b379e/2529-3
00:17:51.729 --> 00:17:56.318
actually went and confirmed with
with action or the surface

51126870-83bf-4ff6-a279-31b8662b379e/2529-4
00:17:56.318 --> 00:18:00.983
injector. And that's because the
mining company doesn't love

51126870-83bf-4ff6-a279-31b8662b379e/2529-5
00:18:00.983 --> 00:18:05.725
people coming to their mind. So
there was only like one small

51126870-83bf-4ff6-a279-31b8662b379e/2529-6
00:18:05.725 --> 00:18:07.255
field team had like.

51126870-83bf-4ff6-a279-31b8662b379e/2552-0
00:18:07.335 --> 00:18:10.382
Half a day, and that's all they
got. No one else has really been

51126870-83bf-4ff6-a279-31b8662b379e/2552-1
00:18:10.382 --> 00:18:13.429
there besides that. But they did
confirm this. So we can see pre

51126870-83bf-4ff6-a279-31b8662b379e/2552-2
00:18:13.429 --> 00:18:13.945
earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/2568-0
00:18:14.735 --> 00:18:17.964
Not a bunch of dark stuff. Post
earthquake. All of this stuff

51126870-83bf-4ff6-a279-31b8662b379e/2568-1
00:18:17.964 --> 00:18:19.475
was ejected onto the surface.

51126870-83bf-4ff6-a279-31b8662b379e/2578-0
00:18:20.825 --> 00:18:23.805
If we look to the central
portion of the lake bed.

51126870-83bf-4ff6-a279-31b8662b379e/2591-0
00:18:24.855 --> 00:18:28.879
There's some some weird stuff
going on, right? So we see a

51126870-83bf-4ff6-a279-31b8662b379e/2591-1
00:18:28.879 --> 00:18:29.425
similar.

51126870-83bf-4ff6-a279-31b8662b379e/2617-0
00:18:30.595 --> 00:18:33.951
Kind of material or surface
reflectance post earthquake was

51126870-83bf-4ff6-a279-31b8662b379e/2617-1
00:18:33.951 --> 00:18:37.475
very dark material being ejected
onto the surface, but in this

51126870-83bf-4ff6-a279-31b8662b379e/2617-2
00:18:37.475 --> 00:18:39.545
case it's in this hexagonal
pattern.

51126870-83bf-4ff6-a279-31b8662b379e/2620-0
00:18:40.955 --> 00:18:41.755
Which is weird.

51126870-83bf-4ff6-a279-31b8662b379e/2633-0
00:18:42.785 --> 00:18:45.748
This is not normal. For those of
you who don't know about Flip

51126870-83bf-4ff6-a279-31b8662b379e/2633-1
00:18:45.748 --> 00:18:46.125
faction.

51126870-83bf-4ff6-a279-31b8662b379e/2656-0
00:18:47.345 --> 00:18:51.754
So now I was like, what's going
on here? Let's try to figure

51126870-83bf-4ff6-a279-31b8662b379e/2656-1
00:18:51.754 --> 00:18:56.091
this out. So this is a pre
earthquake image post earthquake

51126870-83bf-4ff6-a279-31b8662b379e/2656-2
00:18:56.091 --> 00:18:56.525
image.

51126870-83bf-4ff6-a279-31b8662b379e/2679-0
00:18:57.285 --> 00:19:01.630
I just outlined a few hexagons
if they weren't like visually

51126870-83bf-4ff6-a279-31b8662b379e/2679-1
00:19:01.630 --> 00:19:05.690
obvious to you. So before the
earthquake, this hexagonal

51126870-83bf-4ff6-a279-31b8662b379e/2679-2
00:19:05.690 --> 00:19:07.115
pattern was present.

51126870-83bf-4ff6-a279-31b8662b379e/2725-0
00:19:09.745 --> 00:19:13.901
So this was not something you
know related at first. I was

51126870-83bf-4ff6-a279-31b8662b379e/2725-1
00:19:13.901 --> 00:19:17.846
like mud cracks, but some mud
cracks. This is very much

51126870-83bf-4ff6-a279-31b8662b379e/2725-2
00:19:17.846 --> 00:19:22.425
related to the mining operation
and specifically it's related to

51126870-83bf-4ff6-a279-31b8662b379e/2725-3
00:19:22.425 --> 00:19:26.581
solution mining. So solution
mining is a technique used to

51126870-83bf-4ff6-a279-31b8662b379e/2725-4
00:19:26.581 --> 00:19:30.245
extract evaporate minerals from
the subsurface and.

51126870-83bf-4ff6-a279-31b8662b379e/2742-0
00:19:31.495 --> 00:19:36.375
Essentially what is done is
fresh water is injected into the

51126870-83bf-4ff6-a279-31b8662b379e/2742-1
00:19:36.375 --> 00:19:37.255
subsurface.

51126870-83bf-4ff6-a279-31b8662b379e/2758-0
00:19:37.535 --> 00:19:43.295
Umm in kind of hexagonal nodes,
right? And that water dissolves

51126870-83bf-4ff6-a279-31b8662b379e/2758-1
00:19:43.295 --> 00:19:45.725
material in the subsurface?

51126870-83bf-4ff6-a279-31b8662b379e/2769-0
00:19:46.425 --> 00:19:50.915
And it is unpumped out of wells
that are.

51126870-83bf-4ff6-a279-31b8662b379e/2778-0
00:19:52.655 --> 00:19:56.445
Located at the center of each
hexagonal node.

51126870-83bf-4ff6-a279-31b8662b379e/2800-0
00:19:59.175 --> 00:20:03.906
So that's what's going on. So
mining clearly influenced where

51126870-83bf-4ff6-a279-31b8662b379e/2800-1
00:20:03.906 --> 00:20:08.256
the adjective manifested. This
is a very good example of

51126870-83bf-4ff6-a279-31b8662b379e/2800-2
00:20:08.256 --> 00:20:09.325
anthropogenic.

51126870-83bf-4ff6-a279-31b8662b379e/2809-0
00:20:10.615 --> 00:20:13.357
Anthropogenically controlled
manifestation of of

51126870-83bf-4ff6-a279-31b8662b379e/2809-1
00:20:13.357 --> 00:20:14.085
liquefaction.

51126870-83bf-4ff6-a279-31b8662b379e/2818-0
00:20:15.605 --> 00:20:18.865
But like, why? Why are we seeing
this?

51126870-83bf-4ff6-a279-31b8662b379e/2851-0
00:20:20.085 --> 00:20:23.397
So the way that we're going to
approach this is we're going to

51126870-83bf-4ff6-a279-31b8662b379e/2851-1
00:20:23.397 --> 00:20:26.552
use those three tools that I
talked about in the beginning,

51126870-83bf-4ff6-a279-31b8662b379e/2851-2
00:20:26.552 --> 00:20:29.812
geology, geotechnical data and
remote sensing in this case in

51126870-83bf-4ff6-a279-31b8662b379e/2851-3
00:20:29.812 --> 00:20:30.075
Star.

51126870-83bf-4ff6-a279-31b8662b379e/2874-0
00:20:31.845 --> 00:20:35.862
Umm, we're gonna use geology to
try to figure out what the

51126870-83bf-4ff6-a279-31b8662b379e/2874-1
00:20:35.862 --> 00:20:40.287
subsurface is composed of. We're
gonna look at geotechnical data

51126870-83bf-4ff6-a279-31b8662b379e/2874-2
00:20:40.287 --> 00:20:41.105
CPT data to.

51126870-83bf-4ff6-a279-31b8662b379e/2883-0
00:20:42.075 --> 00:20:47.825
See how subsurface behaves.
Colors are really really off.

51126870-83bf-4ff6-a279-31b8662b379e/2898-0
00:20:49.065 --> 00:20:54.420
And we're gonna use insar to
understand exactly what is going

51126870-83bf-4ff6-a279-31b8662b379e/2898-1
00:20:54.420 --> 00:20:56.235
on in the subsurface.

51126870-83bf-4ff6-a279-31b8662b379e/2902-0
00:20:57.515 --> 00:20:58.485
So we'll start with geology.

51126870-83bf-4ff6-a279-31b8662b379e/2924-0
00:20:59.405 --> 00:21:04.522
So as I mentioned seriously is
heavily mined. It's been mined

51126870-83bf-4ff6-a279-31b8662b379e/2924-1
00:21:04.522 --> 00:21:09.475
for a really long time, mostly
Borax and soda ash. Curious.

51126870-83bf-4ff6-a279-31b8662b379e/2939-0
00:21:11.355 --> 00:21:16.285
There's a little fun picture of
the mining back in the day and.

51126870-83bf-4ff6-a279-31b8662b379e/2966-0
00:21:17.365 --> 00:21:20.831
Because of that, the US has
actually taken a lot of cores

51126870-83bf-4ff6-a279-31b8662b379e/2966-1
00:21:20.831 --> 00:21:24.655
throughout the lake bed, so we
actually have a pretty good idea

51126870-83bf-4ff6-a279-31b8662b379e/2966-2
00:21:24.655 --> 00:21:27.345
spatially what's going on in the
subsurface.

51126870-83bf-4ff6-a279-31b8662b379e/3030-0
00:21:28.185 --> 00:21:32.239
And if we take a cross section
of that, I actually didn't make

51126870-83bf-4ff6-a279-31b8662b379e/3030-1
00:21:32.239 --> 00:21:35.972
personally make, this is my
recreation of a cross section

51126870-83bf-4ff6-a279-31b8662b379e/3030-2
00:21:35.972 --> 00:21:39.898
that was published in 1979. But
if we look at it, we can see

51126870-83bf-4ff6-a279-31b8662b379e/3030-3
00:21:39.898 --> 00:21:44.017
that in the central portion of
the lake bed, we have very thick

51126870-83bf-4ff6-a279-31b8662b379e/3030-4
00:21:44.017 --> 00:21:47.878
evaporate deposits and they thin
towards the edges. They're

51126870-83bf-4ff6-a279-31b8662b379e/3030-5
00:21:47.878 --> 00:21:49.745
mostly kind of blends shaped.

51126870-83bf-4ff6-a279-31b8662b379e/3038-0
00:21:51.025 --> 00:21:53.845
And between the evaporate
deposits that are the.

51126870-83bf-4ff6-a279-31b8662b379e/3066-0
00:21:55.105 --> 00:22:00.546
Units of interest for mining are
what all the publications on

51126870-83bf-4ff6-a279-31b8662b379e/3066-1
00:22:00.546 --> 00:22:06.250
this call mud and what they mean
by mud is a combination of clay

51126870-83bf-4ff6-a279-31b8662b379e/3066-2
00:22:06.250 --> 00:22:08.445
and clay, silt and moral.

51126870-83bf-4ff6-a279-31b8662b379e/3083-0
00:22:09.195 --> 00:22:12.547
If you actually go in and read
the the logs, the central link

51126870-83bf-4ff6-a279-31b8662b379e/3083-1
00:22:12.547 --> 00:22:13.845
that is almost all clay.

51126870-83bf-4ff6-a279-31b8662b379e/3111-0
00:22:14.885 --> 00:22:18.153
And as you go towards the edges
of the lake bed, it kind of

51126870-83bf-4ff6-a279-31b8662b379e/3111-1
00:22:18.153 --> 00:22:21.422
grades into very fine clay and
very fine sands, things like

51126870-83bf-4ff6-a279-31b8662b379e/3111-2
00:22:21.422 --> 00:22:22.185
that silt too.

51126870-83bf-4ff6-a279-31b8662b379e/3133-0
00:22:24.765 --> 00:22:29.315
If we go back to our whole what
is liquefaction question? If you

51126870-83bf-4ff6-a279-31b8662b379e/3133-1
00:22:29.315 --> 00:22:32.045
remember at the beginning I said
that.

51126870-83bf-4ff6-a279-31b8662b379e/3149-0
00:22:32.855 --> 00:22:37.155
Liquefaction mainly occurs in
loosely packed sand. Sand

51126870-83bf-4ff6-a279-31b8662b379e/3149-1
00:22:37.155 --> 00:22:39.305
dominated environments here.

51126870-83bf-4ff6-a279-31b8662b379e/3155-0
00:22:41.485 --> 00:22:44.055
You can you can tell that.

51126870-83bf-4ff6-a279-31b8662b379e/3185-0
00:22:44.905 --> 00:22:48.033
Is this weird? There is no sand
right in the centre, especially

51126870-83bf-4ff6-a279-31b8662b379e/3185-1
00:22:48.033 --> 00:22:51.113
in the central portion of the
lake bed. So we really would not

51126870-83bf-4ff6-a279-31b8662b379e/3185-2
00:22:51.113 --> 00:22:52.825
expect any local faction to
occur.

51126870-83bf-4ff6-a279-31b8662b379e/3187-0
00:22:53.905 --> 00:22:54.475
Umm.

51126870-83bf-4ff6-a279-31b8662b379e/3262-0
00:22:56.745 --> 00:23:01.101
This is just a 2 if you weren't
already commenced. For whatever

51126870-83bf-4ff6-a279-31b8662b379e/3262-1
00:23:01.101 --> 00:23:05.322
reason, these are two logs, one
from China like which is very

51126870-83bf-4ff6-a279-31b8662b379e/3262-2
00:23:05.322 --> 00:23:09.339
close to where the Ridgecrest
look like ruptured and zeros

51126870-83bf-4ff6-a279-31b8662b379e/3262-3
00:23:09.339 --> 00:23:13.423
like here. They actually have
very different geologies, but

51126870-83bf-4ff6-a279-31b8662b379e/3262-4
00:23:13.423 --> 00:23:17.780
I'm happy to talk about why that
is, but essentially China Lake

51126870-83bf-4ff6-a279-31b8662b379e/3262-5
00:23:17.780 --> 00:23:21.525
does have a lot of sandy
material where again, serious

51126870-83bf-4ff6-a279-31b8662b379e/3262-6
00:23:21.525 --> 00:23:23.295
lake has essentially none.

51126870-83bf-4ff6-a279-31b8662b379e/3272-0
00:23:28.075 --> 00:23:31.223
All right. So that's geology.
Let's talk a little about the

51126870-83bf-4ff6-a279-31b8662b379e/3272-1
00:23:31.223 --> 00:23:31.905
geotech data.

51126870-83bf-4ff6-a279-31b8662b379e/3297-0
00:23:33.965 --> 00:23:39.545
So specifically the data I use
is called CPT data, which is a

51126870-83bf-4ff6-a279-31b8662b379e/3297-1
00:23:39.545 --> 00:23:44.855
cone penetration test and it's a
way to measure subsurface

51126870-83bf-4ff6-a279-31b8662b379e/3297-2
00:23:44.855 --> 00:23:46.475
properties, right?

51126870-83bf-4ff6-a279-31b8662b379e/3341-0
00:23:47.745 --> 00:23:52.161
So during the CBT collection,
you basically take a rod with

51126870-83bf-4ff6-a279-31b8662b379e/3341-1
00:23:52.161 --> 00:23:56.504
sensors, shove it into the
ground and measure how how much

51126870-83bf-4ff6-a279-31b8662b379e/3341-2
00:23:56.504 --> 00:24:01.068
resistance you get to pushing it
into the ground and what the

51126870-83bf-4ff6-a279-31b8662b379e/3341-3
00:24:01.068 --> 00:24:05.926
friction is of the material kind
of passing by along the edges of

51126870-83bf-4ff6-a279-31b8662b379e/3341-4
00:24:05.926 --> 00:24:06.515
the rod.

51126870-83bf-4ff6-a279-31b8662b379e/3379-0
00:24:08.115 --> 00:24:12.029
And the state is not as widely
collected as the the geologic

51126870-83bf-4ff6-a279-31b8662b379e/3379-1
00:24:12.029 --> 00:24:16.071
core is the only data we have is
right here on the edge of the

51126870-83bf-4ff6-a279-31b8662b379e/3379-2
00:24:16.071 --> 00:24:20.178
lake bed. This was all collected
because high school is located

51126870-83bf-4ff6-a279-31b8662b379e/3379-3
00:24:20.178 --> 00:24:21.975
here and they wanted to see.

51126870-83bf-4ff6-a279-31b8662b379e/3387-0
00:24:23.405 --> 00:24:27.995
How the graph would act babe so.

51126870-83bf-4ff6-a279-31b8662b379e/3395-0
00:24:29.335 --> 00:24:31.705
If you remember, if you recall
from this.

51126870-83bf-4ff6-a279-31b8662b379e/3424-0
00:24:33.945 --> 00:24:37.488
A cross section, the edge of the
lake bed is actually the only

51126870-83bf-4ff6-a279-31b8662b379e/3424-1
00:24:37.488 --> 00:24:40.975
place where we really see sandy
material. So if we go back to

51126870-83bf-4ff6-a279-31b8662b379e/3424-2
00:24:40.975 --> 00:24:44.237
where the happened, it would
probably be out there on the

51126870-83bf-4ff6-a279-31b8662b379e/3424-3
00:24:44.237 --> 00:24:45.475
edge of the like that.

51126870-83bf-4ff6-a279-31b8662b379e/3439-0
00:24:46.895 --> 00:24:51.855
It's just just for context. So
here's an example log CPT log.

51126870-83bf-4ff6-a279-31b8662b379e/3458-0
00:24:53.425 --> 00:24:57.169
You don't need to glean a lot of
information from this. Besides,

51126870-83bf-4ff6-a279-31b8662b379e/3458-1
00:24:57.169 --> 00:24:59.935
I'm showing you that code
resistance, friction.

51126870-83bf-4ff6-a279-31b8662b379e/3465-0
00:25:01.055 --> 00:25:03.425
How those two relate to each
other?

51126870-83bf-4ff6-a279-31b8662b379e/3477-0
00:25:05.175 --> 00:25:09.365
Is can be kind of plotted on on
a like an XY axis.

51126870-83bf-4ff6-a279-31b8662b379e/3486-0
00:25:09.895 --> 00:25:14.655
Uh, and over many, many, many
years of.

51126870-83bf-4ff6-a279-31b8662b379e/3512-0
00:25:15.525 --> 00:25:20.678
Many people doing tests, either
lab or in the field, these kind

51126870-83bf-4ff6-a279-31b8662b379e/3512-1
00:25:20.678 --> 00:25:25.268
of divisions between divisions
plotted on this plot have

51126870-83bf-4ff6-a279-31b8662b379e/3512-2
00:25:25.268 --> 00:25:26.235
resulted in.

51126870-83bf-4ff6-a279-31b8662b379e/3532-0
00:25:26.855 --> 00:25:30.304
Umm these categories and the
only and they're listed over

51126870-83bf-4ff6-a279-31b8662b379e/3532-1
00:25:30.304 --> 00:25:34.052
here. I'm not gonna. They're not
super important. Really. Just

51126870-83bf-4ff6-a279-31b8662b379e/3532-2
00:25:34.052 --> 00:25:34.885
the fact that.

51126870-83bf-4ff6-a279-31b8662b379e/3574-0
00:25:35.805 --> 00:25:40.116
Liquefaction is really known to
occur in this sans like

51126870-83bf-4ff6-a279-31b8662b379e/3574-1
00:25:40.116 --> 00:25:45.121
contractive category, which I've
highlighted in green, and if we

51126870-83bf-4ff6-a279-31b8662b379e/3574-2
00:25:45.121 --> 00:25:49.818
just take all of these points
from all the CPT logs and plot

51126870-83bf-4ff6-a279-31b8662b379e/3574-3
00:25:49.818 --> 00:25:52.205
them in terms of total percent.

51126870-83bf-4ff6-a279-31b8662b379e/3598-0
00:25:52.765 --> 00:25:56.198
Uh, there's actually very little
traditionally liquifiable

51126870-83bf-4ff6-a279-31b8662b379e/3598-1
00:25:56.198 --> 00:25:59.981
material, even on the very edge
of the lake bed, where you would

51126870-83bf-4ff6-a279-31b8662b379e/3598-2
00:25:59.981 --> 00:26:01.785
expect there to be more, right?

51126870-83bf-4ff6-a279-31b8662b379e/3669-0
00:26:03.445 --> 00:26:07.134
OK. So from geology, we know
what things are made of. Mostly

51126870-83bf-4ff6-a279-31b8662b379e/3669-1
00:26:07.134 --> 00:26:10.400
evaporates clays and silts,
which are not traditional

51126870-83bf-4ff6-a279-31b8662b379e/3669-2
00:26:10.400 --> 00:26:14.029
liquifiable. The CPT data is
like, Yep, this material isn't

51126870-83bf-4ff6-a279-31b8662b379e/3669-3
00:26:14.029 --> 00:26:17.718
traditionally like a viable it
doesn't behave like sediments

51126870-83bf-4ff6-a279-31b8662b379e/3669-4
00:26:17.718 --> 00:26:21.649
that would look would behave. So
I think from that. Hopefully if

51126870-83bf-4ff6-a279-31b8662b379e/3669-5
00:26:21.649 --> 00:26:25.339
minced you that liquefaction all
of that surface ejecta that

51126870-83bf-4ff6-a279-31b8662b379e/3669-6
00:26:25.339 --> 00:26:28.484
we're seeing that super
extensive surface objective

51126870-83bf-4ff6-a279-31b8662b379e/3669-7
00:26:28.484 --> 00:26:31.810
throughout the lake bed is
probably not related to the

51126870-83bf-4ff6-a279-31b8662b379e/3669-8
00:26:31.810 --> 00:26:32.355
question.

51126870-83bf-4ff6-a279-31b8662b379e/3710-0
00:26:33.975 --> 00:26:38.519
Umm, alright, so let's talk
about insar. Just my favorite

51126870-83bf-4ff6-a279-31b8662b379e/3710-1
00:26:38.519 --> 00:26:43.533
thing. So with the insert data,
we're really only gonna look at

51126870-83bf-4ff6-a279-31b8662b379e/3710-2
00:26:43.533 --> 00:26:48.312
how the ground deforms or moves
before the earthquake, right

51126870-83bf-4ff6-a279-31b8662b379e/3710-3
00:26:48.312 --> 00:26:53.091
leading up to the earthquake,
we're not really going to look

51126870-83bf-4ff6-a279-31b8662b379e/3710-4
00:26:53.091 --> 00:26:54.815
at at after or during.

51126870-83bf-4ff6-a279-31b8662b379e/3751-0
00:26:55.495 --> 00:26:59.202
If you're unfamiliar with
Insight data, everyone's

51126870-83bf-4ff6-a279-31b8662b379e/3751-1
00:26:59.202 --> 00:27:03.129
favorite slide, hopefully
someone out there has never

51126870-83bf-4ff6-a279-31b8662b379e/3751-2
00:27:03.129 --> 00:27:07.273
heard of it in Star stands for
interferometric synthetic

51126870-83bf-4ff6-a279-31b8662b379e/3751-3
00:27:07.273 --> 00:27:11.344
aperture radar, and it's a very
cool way to measure the

51126870-83bf-4ff6-a279-31b8662b379e/3751-4
00:27:11.344 --> 00:27:15.925
displacement of the ground by
essentially kind of interfering.

51126870-83bf-4ff6-a279-31b8662b379e/3782-0
00:27:17.075 --> 00:27:21.186
The the phase of two radar
images taken at 2 separate times

51126870-83bf-4ff6-a279-31b8662b379e/3782-1
00:27:21.186 --> 00:27:25.298
and that phase difference can
relate to how much the ground

51126870-83bf-4ff6-a279-31b8662b379e/3782-2
00:27:25.298 --> 00:27:28.725
has moved between the two. Great
our acts issues.

51126870-83bf-4ff6-a279-31b8662b379e/3802-0
00:27:30.535 --> 00:27:34.857
All right, here's our context
figure. Hopefully you're

51126870-83bf-4ff6-a279-31b8662b379e/3802-1
00:27:34.857 --> 00:27:39.886
familiar here is forgot to put a
skill on this. I'm sorry. This

51126870-83bf-4ff6-a279-31b8662b379e/3802-2
00:27:39.886 --> 00:27:42.165
is the vertical component of.

51126870-83bf-4ff6-a279-31b8662b379e/3836-0
00:27:43.165 --> 00:27:47.899
The secular rate, so this is
just an average rate through

51126870-83bf-4ff6-a279-31b8662b379e/3836-1
00:27:47.899 --> 00:27:52.878
time from 2015 to 2019 mid 2019
before the earthquake. If we

51126870-83bf-4ff6-a279-31b8662b379e/3836-2
00:27:52.878 --> 00:27:55.735
zoom in to where our hexagons
are.

51126870-83bf-4ff6-a279-31b8662b379e/3865-0
00:27:57.045 --> 00:28:01.904
You can see like I was super
surprised at how clear this is,

51126870-83bf-4ff6-a279-31b8662b379e/3865-1
00:28:01.904 --> 00:28:06.524
right. It's very obvious that
very there's very localized

51126870-83bf-4ff6-a279-31b8662b379e/3865-2
00:28:06.524 --> 00:28:11.145
subsidence around the edges of
of each of these hexagons.

51126870-83bf-4ff6-a279-31b8662b379e/3873-0
00:28:12.415 --> 00:28:15.685
So if we go back to our
solution, mining.

51126870-83bf-4ff6-a279-31b8662b379e/3898-0
00:28:16.575 --> 00:28:21.548
Things we can kind of relate
where we're getting injection,

51126870-83bf-4ff6-a279-31b8662b379e/3898-1
00:28:21.548 --> 00:28:26.605
which is the blue dots around
the edges of the the hexagons.

51126870-83bf-4ff6-a279-31b8662b379e/3906-0
00:28:27.345 --> 00:28:31.395
And where fluid is being
extracted, right?

51126870-83bf-4ff6-a279-31b8662b379e/3909-0
00:28:32.565 --> 00:28:33.335
So.

51126870-83bf-4ff6-a279-31b8662b379e/3912-0
00:28:34.615 --> 00:28:35.675
Typically.

51126870-83bf-4ff6-a279-31b8662b379e/3964-0
00:28:38.195 --> 00:28:41.772
At least in the insular world,
and I think the rest of the

51126870-83bf-4ff6-a279-31b8662b379e/3964-1
00:28:41.772 --> 00:28:45.471
world, when you inject fluid
into the subsurface, you do not

51126870-83bf-4ff6-a279-31b8662b379e/3964-2
00:28:45.471 --> 00:28:49.412
expect that surface to go down.
You expect it to either go up or

51126870-83bf-4ff6-a279-31b8662b379e/3964-3
00:28:49.412 --> 00:28:53.171
stay the same or whatever. When
you extract fluid, you expect

51126870-83bf-4ff6-a279-31b8662b379e/3964-4
00:28:53.171 --> 00:28:56.324
the subsurface to get out,
right? We are seeing the

51126870-83bf-4ff6-a279-31b8662b379e/3964-5
00:28:56.324 --> 00:28:57.355
opposite of that.

51126870-83bf-4ff6-a279-31b8662b379e/3975-0
00:28:58.775 --> 00:29:02.618
The ground is actually subsiding
faster around fluid injection

51126870-83bf-4ff6-a279-31b8662b379e/3975-1
00:29:02.618 --> 00:29:02.985
sites.

51126870-83bf-4ff6-a279-31b8662b379e/3977-0
00:29:04.565 --> 00:29:05.025
And.

51126870-83bf-4ff6-a279-31b8662b379e/3985-0
00:29:05.795 --> 00:29:09.315
So what? What? What? Definitely
injecting that.

51126870-83bf-4ff6-a279-31b8662b379e/4114-0
00:29:54.955 --> 00:29:59.142
OK, so this is just because I
think it's cool. It's not super

51126870-83bf-4ff6-a279-31b8662b379e/4114-1
00:29:59.142 --> 00:30:02.115
important to the story, but for
people who.

51126870-83bf-4ff6-a279-31b8662b379e/4138-0
00:30:03.065 --> 00:30:07.780
Appreciate and sorry I I think
you'll appreciate this. So these

51126870-83bf-4ff6-a279-31b8662b379e/4138-1
00:30:07.780 --> 00:30:11.907
again, these are the hexagons
I've now just colored the

51126870-83bf-4ff6-a279-31b8662b379e/4138-2
00:30:11.907 --> 00:30:14.265
surface ejecta material. Red is.

51126870-83bf-4ff6-a279-31b8662b379e/4218-0
00:30:47.875 --> 00:30:48.885
The time series.

51126870-83bf-4ff6-a279-31b8662b379e/4453-0
00:32:14.045 --> 00:32:18.845
So step one is solution. Mining
initiates. I'll talk about this

51126870-83bf-4ff6-a279-31b8662b379e/4453-1
00:32:18.845 --> 00:32:23.570
later, but I don't think it's
just solution mining that causes

51126870-83bf-4ff6-a279-31b8662b379e/4453-2
00:32:23.570 --> 00:32:27.470
this. So this is where
freshwater is being injected

51126870-83bf-4ff6-a279-31b8662b379e/4453-3
00:32:27.470 --> 00:32:31.745
into the subsurface, and briny
water is being extracted.

51126870-83bf-4ff6-a279-31b8662b379e/4564-0
00:33:15.935 --> 00:33:18.967
From the earthquake causes that
collapse and causes the

51126870-83bf-4ff6-a279-31b8662b379e/4564-1
00:33:18.967 --> 00:33:21.025
injection of fluids onto the
surface.

51126870-83bf-4ff6-a279-31b8662b379e/4641-0
00:33:57.385 --> 00:33:57.835
All right.

51126870-83bf-4ff6-a279-31b8662b379e/4764-0
00:34:34.645 --> 00:34:38.105
Like this was one earthquake.
This one area. It's very like

51126870-83bf-4ff6-a279-31b8662b379e/4764-1
00:34:38.105 --> 00:34:41.622
niche environment. Like, who
cares? And this I will actually

51126870-83bf-4ff6-a279-31b8662b379e/4764-2
00:34:41.622 --> 00:34:44.564
go back to kind of the
earthquake triggered ground

51126870-83bf-4ff6-a279-31b8662b379e/4764-3
00:34:44.564 --> 00:34:48.254
model now because it turns out I
do think this has implications

51126870-83bf-4ff6-a279-31b8662b379e/4764-4
00:34:48.254 --> 00:34:51.715
beyond just this earthquake and
implications for the model.

51126870-83bf-4ff6-a279-31b8662b379e/4818-0
00:35:10.205 --> 00:35:14.113
And I'm going to do this by
first discussing the extent of

51126870-83bf-4ff6-a279-31b8662b379e/4818-1
00:35:14.113 --> 00:35:17.425
service ejecta in serials like
versus China like.

51126870-83bf-4ff6-a279-31b8662b379e/4850-0
00:35:29.415 --> 00:35:31.745
So if we go back to our.

51126870-83bf-4ff6-a279-31b8662b379e/4909-0
00:35:53.935 --> 00:35:57.965
Acted or or, uh yeah. Loosely
packed.

51126870-83bf-4ff6-a279-31b8662b379e/4945-0
00:36:09.385 --> 00:36:14.506
But if we look at that, that
kind of optical change detection

51126870-83bf-4ff6-a279-31b8662b379e/4945-1
00:36:14.506 --> 00:36:15.415
stuff here.

51126870-83bf-4ff6-a279-31b8662b379e/5080-0
00:37:11.195 --> 00:37:14.224
Walk through what we see with
the Ridgecrest earthquake and

51126870-83bf-4ff6-a279-31b8662b379e/5080-1
00:37:14.224 --> 00:37:17.305
then compare it to what we see
from the contract earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/5086-0
00:37:18.385 --> 00:37:21.695
So pre event here are hexagons.

51126870-83bf-4ff6-a279-31b8662b379e/5092-0
00:37:22.565 --> 00:37:24.055
A bunch of white stuff.

51126870-83bf-4ff6-a279-31b8662b379e/5116-0
00:37:30.995 --> 00:37:32.015
I've turned very dark.

51126870-83bf-4ff6-a279-31b8662b379e/5147-0
00:37:38.975 --> 00:37:44.033
So the reason for that I this is
kind of my my hypothesis

51126870-83bf-4ff6-a279-31b8662b379e/5147-1
00:37:44.033 --> 00:37:49.005
hypothesis, but I think what's
happening is essentially.

51126870-83bf-4ff6-a279-31b8662b379e/5171-0
00:37:59.955 --> 00:38:01.255
And UM.

51126870-83bf-4ff6-a279-31b8662b379e/5291-0
00:38:53.595 --> 00:38:54.305
Prevent.

51126870-83bf-4ff6-a279-31b8662b379e/5391-0
00:39:40.775 --> 00:39:42.525
Cavity collapse.

51126870-83bf-4ff6-a279-31b8662b379e/5460-0
00:39:59.985 --> 00:40:03.382
It was actually, yes, the
greatest number of liquefaction

51126870-83bf-4ff6-a279-31b8662b379e/5460-1
00:40:03.382 --> 00:40:06.721
observations that are currently
in the USGS liquefaction

51126870-83bf-4ff6-a279-31b8662b379e/5460-2
00:40:06.721 --> 00:40:10.470
inventory that is input into our
model actually comes from this

51126870-83bf-4ff6-a279-31b8662b379e/5460-3
00:40:10.470 --> 00:40:11.115
earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/5639-0
00:41:25.345 --> 00:41:28.775
Cereals like then we do or.
Sorry. So we see a lot more

51126870-83bf-4ff6-a279-31b8662b379e/5639-1
00:41:28.775 --> 00:41:32.635
surface ejecta and serials like
than anywhere else in the area

51126870-83bf-4ff6-a279-31b8662b379e/5639-2
00:41:32.635 --> 00:41:34.535
from the Ridgecrest earthquake.

51126870-83bf-4ff6-a279-31b8662b379e/5729-0
00:42:10.315 --> 00:42:14.144
That could be why and I have not
personally tested it, but we've

51126870-83bf-4ff6-a279-31b8662b379e/5729-1
00:42:14.144 --> 00:42:15.205
been working with.

51126870-83bf-4ff6-a279-31b8662b379e/5762-0
00:42:16.405 --> 00:42:20.726
People some way. Wei song, who's
currently at UT Austin. He

51126870-83bf-4ff6-a279-31b8662b379e/5762-1
00:42:20.726 --> 00:42:25.408
tested this. He removed the data
from the Gujarat earthquake and

51126870-83bf-4ff6-a279-31b8662b379e/5762-2
00:42:25.408 --> 00:42:29.874
that actually did really the
model. So yeah, maybe why things

51126870-83bf-4ff6-a279-31b8662b379e/5762-3
00:42:29.874 --> 00:42:30.595
messed up.

51126870-83bf-4ff6-a279-31b8662b379e/5824-0
00:42:59.285 --> 00:42:59.725
Uh.

51126870-83bf-4ff6-a279-31b8662b379e/5934-0
00:43:43.365 --> 00:43:48.157
How people can exacerbate and
also kind of regulate where

51126870-83bf-4ff6-a279-31b8662b379e/5934-1
00:43:48.157 --> 00:43:51.875
ground failure manifests during
earthquakes.

51126870-83bf-4ff6-a279-31b8662b379e/5951-0
00:43:53.135 --> 00:43:56.689
And maybe should just, I don't
know. I mean, it's it. I don't

51126870-83bf-4ff6-a279-31b8662b379e/5951-1
00:43:56.689 --> 00:43:59.785
think a lot of people have
thought about the idea of.

51126870-83bf-4ff6-a279-31b8662b379e/5973-0
00:44:00.935 --> 00:44:04.801
Can be actually direct where
ground failure occurs from

51126870-83bf-4ff6-a279-31b8662b379e/5973-1
00:44:04.801 --> 00:44:08.391
earthquakes, and this is
potentially an interesting

51126870-83bf-4ff6-a279-31b8662b379e/5973-2
00:44:08.391 --> 00:44:10.255
example showing like maybe.

51126870-83bf-4ff6-a279-31b8662b379e/6003-0
00:44:10.935 --> 00:44:14.281
Especially if you create
situation that all happen

51126870-83bf-4ff6-a279-31b8662b379e/6003-1
00:44:14.281 --> 00:44:18.151
underneath that, but it it.
Yeah. So yeah, who knows? Lots

51126870-83bf-4ff6-a279-31b8662b379e/6003-2
00:44:18.151 --> 00:44:20.645
to think about. So that's all I
have.

51126870-83bf-4ff6-a279-31b8662b379e/6105-0
00:45:13.645 --> 00:45:19.473
I could like, I mean probably
guess very like ARM wave guess,

51126870-83bf-4ff6-a279-31b8662b379e/6105-1
00:45:19.473 --> 00:45:22.105
but yeah, there's unless we.

51126870-83bf-4ff6-a279-31b8662b379e/6110-0
00:45:24.225 --> 00:45:25.075
Figure out.

51126870-83bf-4ff6-a279-31b8662b379e/6160-0
00:45:39.915 --> 00:45:43.275
Yeah, unless I can find other
examples and I'm not sure we can

51126870-83bf-4ff6-a279-31b8662b379e/6160-1
00:45:43.275 --> 00:45:46.475
actually like build a separate
model, but it would be cool.

51126870-83bf-4ff6-a279-31b8662b379e/6276-0
00:46:26.095 --> 00:46:29.477
I might need to stop you never
remember if I can actually see

51126870-83bf-4ff6-a279-31b8662b379e/6276-1
00:46:29.477 --> 00:46:31.715
the chat. Then we can switch to
another.

51126870-83bf-4ff6-a279-31b8662b379e/6373-0
00:47:24.895 --> 00:47:27.085
Right, right. Can you?

51126870-83bf-4ff6-a279-31b8662b379e/6374-0
00:47:26.815 --> 00:47:27.135
Yeah.

51126870-83bf-4ff6-a279-31b8662b379e/6434-0
00:47:32.575 --> 00:47:36.374
Yeah. Yeah. So really nice
talking and it and and actually

51126870-83bf-4ff6-a279-31b8662b379e/6434-1
00:47:36.374 --> 00:47:40.302
also want to say I spent my
first ten years in Singapore. So

51126870-83bf-4ff6-a279-31b8662b379e/6434-2
00:47:40.302 --> 00:47:44.359
hey, nice to hear that you spent
some time there to so I what?

51126870-83bf-4ff6-a279-31b8662b379e/6434-3
00:47:44.359 --> 00:47:48.544
What I was wondering is that you
know what, what can we get from

51126870-83bf-4ff6-a279-31b8662b379e/6434-4
00:47:48.544 --> 00:47:49.575
seismic signals?

51126870-83bf-4ff6-a279-31b8662b379e/6524-0
00:48:19.505 --> 00:48:22.541
Yeah, great question. For a
geotechnical engineer, we're,

51126870-83bf-4ff6-a279-31b8662b379e/6524-1
00:48:22.541 --> 00:48:24.635
I'm, I am a fortunately not, but
I can.

51126870-83bf-4ff6-a279-31b8662b379e/6565-0
00:48:34.145 --> 00:48:37.987
So I don't know if this is this
is just the first thing that

51126870-83bf-4ff6-a279-31b8662b379e/6565-1
00:48:37.987 --> 00:48:42.081
popped into my head is that and
I think this is something Andrew

51126870-83bf-4ff6-a279-31b8662b379e/6565-2
00:48:42.081 --> 00:48:45.735
McGee had mentioned to me at
some point essentially that.

51126870-83bf-4ff6-a279-31b8662b379e/6614-0
00:49:02.525 --> 00:49:05.700
Which is so the ground motion
response at that site where

51126870-83bf-4ff6-a279-31b8662b379e/6614-1
00:49:05.700 --> 00:49:08.875
there is liquefaction in the
subsurface, although it may.

51126870-83bf-4ff6-a279-31b8662b379e/6632-0
00:49:09.565 --> 00:49:14.461
Mess with things on if it you
know objects at the surface of

51126870-83bf-4ff6-a279-31b8662b379e/6632-1
00:49:14.461 --> 00:49:18.475
the actual shaking may actually
be like dampened.

51126870-83bf-4ff6-a279-31b8662b379e/6648-0
00:49:27.495 --> 00:49:29.165
Uh, but I know that that.

51126870-83bf-4ff6-a279-31b8662b379e/6668-0
00:49:33.695 --> 00:49:37.532
Something. Yeah. So I I'm not
sure I have a good answer to

51126870-83bf-4ff6-a279-31b8662b379e/6668-1
00:49:37.532 --> 00:49:40.265
your question, but I will think
about it.

51126870-83bf-4ff6-a279-31b8662b379e/6690-0
00:49:40.955 --> 00:49:44.559
That that, that is a great
attempt. That's a tall order you

51126870-83bf-4ff6-a279-31b8662b379e/6690-1
00:49:44.559 --> 00:49:48.104
just described. And but again,
nice talk. Really enjoy it,

51126870-83bf-4ff6-a279-31b8662b379e/6690-2
00:49:48.104 --> 00:49:48.465
Paula.

51126870-83bf-4ff6-a279-31b8662b379e/6692-0
00:49:49.165 --> 00:49:49.835
Yeah.

51126870-83bf-4ff6-a279-31b8662b379e/6709-0
00:49:50.645 --> 00:49:53.207
By the way, can continue. You
wanna unmute yourself and ask

51126870-83bf-4ff6-a279-31b8662b379e/6709-1
00:49:53.207 --> 00:49:53.805
your question.

51126870-83bf-4ff6-a279-31b8662b379e/6723-0
00:49:55.705 --> 00:49:59.993
Yeah. Hey, I wanted to say good
job on this talk. It was really

51126870-83bf-4ff6-a279-31b8662b379e/6723-1
00:49:59.993 --> 00:50:00.395
great.

51126870-83bf-4ff6-a279-31b8662b379e/6874-0
00:50:39.035 --> 00:50:42.256
Oh, I was just gonna say
something. I didn't actually

51126870-83bf-4ff6-a279-31b8662b379e/6874-1
00:50:42.256 --> 00:50:45.776
mention in the talk. Is that for
the CPT data, we actually

51126870-83bf-4ff6-a279-31b8662b379e/6874-2
00:50:45.776 --> 00:50:49.296
removed the top feel like the
album or like the like short

51126870-83bf-4ff6-a279-31b8662b379e/6874-3
00:50:49.296 --> 00:50:52.995
deposits, so that we were really
only looking at the material

51126870-83bf-4ff6-a279-31b8662b379e/6874-4
00:50:52.995 --> 00:50:56.754
that or the the level that would
be kind of similar throughout

51126870-83bf-4ff6-a279-31b8662b379e/6874-5
00:50:56.754 --> 00:51:00.572
the lake bed. So we didn't even
like I I agree with you that if

51126870-83bf-4ff6-a279-31b8662b379e/6874-6
00:51:00.572 --> 00:51:04.331
you looked at how lucky like the
soil behavior of the material

51126870-83bf-4ff6-a279-31b8662b379e/6874-7
00:51:04.331 --> 00:51:07.195
that was on top, it would have
been it is like.

51126870-83bf-4ff6-a279-31b8662b379e/6959-0
00:51:34.755 --> 00:51:37.235
I have questions about do you
know?

51126870-83bf-4ff6-a279-31b8662b379e/7043-0
00:51:58.935 --> 00:52:02.182
That there was uh pumping
occurring at that time because

51126870-83bf-4ff6-a279-31b8662b379e/7043-1
00:52:02.182 --> 00:52:05.145
that would further increase
liquefaction if they're

51126870-83bf-4ff6-a279-31b8662b379e/7043-2
00:52:05.145 --> 00:52:08.165
increasing poor pressures
already in the subsurface.

51126870-83bf-4ff6-a279-31b8662b379e/7101-0
00:52:09.125 --> 00:52:13.402
Yeah, that's a great question.
OK. So the first question is you

51126870-83bf-4ff6-a279-31b8662b379e/7101-1
00:52:13.402 --> 00:52:17.212
probably then you probably
notice that I kept saying the

51126870-83bf-4ff6-a279-31b8662b379e/7101-2
00:52:17.212 --> 00:52:21.423
Ridgecrest earthquake and not
the Ridgecrest earthquake series

51126870-83bf-4ff6-a279-31b8662b379e/7101-3
00:52:21.423 --> 00:52:25.634
because there were two at the
time 6.47 point one. There is so

51126870-83bf-4ff6-a279-31b8662b379e/7101-4
00:52:25.634 --> 00:52:29.645
planet collected data not quite
over the hexagons but over.

51126870-83bf-4ff6-a279-31b8662b379e/7125-0
00:52:30.365 --> 00:52:35.044
Most of the western edge of the
lake bed on the 5th. So between

51126870-83bf-4ff6-a279-31b8662b379e/7125-1
00:52:35.044 --> 00:52:39.650
the two earthquakes this fallen
one was first, followed by the

51126870-83bf-4ff6-a279-31b8662b379e/7125-2
00:52:39.650 --> 00:52:40.455
larger one.

51126870-83bf-4ff6-a279-31b8662b379e/7201-0
00:53:08.905 --> 00:53:09.355
Sorry.

51126870-83bf-4ff6-a279-31b8662b379e/7215-0
00:53:12.105 --> 00:53:18.975
I did. Ohh yeah. So your second
question? No, I don't know, but.

51126870-83bf-4ff6-a279-31b8662b379e/7266-0
00:53:37.525 --> 00:53:40.237
The site where all those photos
were taken along that kind of

51126870-83bf-4ff6-a279-31b8662b379e/7266-1
00:53:40.237 --> 00:53:40.675
ephemeral.

51126870-83bf-4ff6-a279-31b8662b379e/7279-0
00:53:41.855 --> 00:53:45.060
A drainage that goes right into
to the southern portion of the

51126870-83bf-4ff6-a279-31b8662b379e/7279-1
00:53:45.060 --> 00:53:45.315
lake.

51126870-83bf-4ff6-a279-31b8662b379e/7350-0
00:53:46.475 --> 00:53:50.471
And see what what's still there.
So I'm happy to share pictures

51126870-83bf-4ff6-a279-31b8662b379e/7350-1
00:53:50.471 --> 00:53:54.219
if you're curious and if you
suggestions of where we should

51126870-83bf-4ff6-a279-31b8662b379e/7350-2
00:53:54.219 --> 00:53:58.153
go, happy that I would be very
happy to hear, but that doesn't

51126870-83bf-4ff6-a279-31b8662b379e/7350-3
00:53:58.153 --> 00:54:02.150
actually answer the question and
it is no, I have no idea. They

51126870-83bf-4ff6-a279-31b8662b379e/7350-4
00:54:02.150 --> 00:54:05.647
were not, but I do have
confidence that like my face to

51126870-83bf-4ff6-a279-31b8662b379e/7350-5
00:54:05.647 --> 00:54:09.144
face interactions with folks,
the mind will really help

51126870-83bf-4ff6-a279-31b8662b379e/7350-6
00:54:09.144 --> 00:54:12.829
clarify some of these things,
including the depth at which

51126870-83bf-4ff6-a279-31b8662b379e/7350-7
00:54:12.829 --> 00:54:15.265
they are extracting like what
they're.

51126870-83bf-4ff6-a279-31b8662b379e/7352-0
00:54:16.195 --> 00:54:16.725
Man.

51126870-83bf-4ff6-a279-31b8662b379e/7361-0
00:54:22.005 --> 00:54:22.355
Nice.

51126870-83bf-4ff6-a279-31b8662b379e/7399-0
00:54:25.315 --> 00:54:28.797
This cavity collapse model
should probably be if it goes

51126870-83bf-4ff6-a279-31b8662b379e/7399-1
00:54:28.797 --> 00:54:32.401
all the way to the surface and
the forms of surface, there

51126870-83bf-4ff6-a279-31b8662b379e/7399-2
00:54:32.401 --> 00:54:35.945
should be circular cracks at the
surface that IT company.

51126870-83bf-4ff6-a279-31b8662b379e/7504-0
00:55:09.965 --> 00:55:10.285
Yeah.

51126870-83bf-4ff6-a279-31b8662b379e/7511-0
00:55:14.475 --> 00:55:16.325
The so so.

51126870-83bf-4ff6-a279-31b8662b379e/7693-0
00:56:28.505 --> 00:56:30.975
It's if it's settled more during
the event or not.

51126870-83bf-4ff6-a279-31b8662b379e/7745-0
00:56:51.245 --> 00:56:52.635
The southern part, so yeah.

51126870-83bf-4ff6-a279-31b8662b379e/7828-0
00:57:02.885 --> 00:57:07.181
The most highly upvoted chat
questions from personal Creamer

51126870-83bf-4ff6-a279-31b8662b379e/7828-1
00:57:07.181 --> 00:57:11.477
if evaporate, liquid fiction is
triggered at lower levels of

51126870-83bf-4ff6-a279-31b8662b379e/7828-2
00:57:11.477 --> 00:57:15.773
shaking. Is this something we
need to be concerned about for

51126870-83bf-4ff6-a279-31b8662b379e/7828-3
00:57:15.773 --> 00:57:20.140
communities like Salt Lake City?
I mean, I would say yes, but

51126870-83bf-4ff6-a279-31b8662b379e/7828-4
00:57:20.140 --> 00:57:20.845
also like.

51126870-83bf-4ff6-a279-31b8662b379e/7861-0
00:57:21.885 --> 00:57:27.279
Not like it's not like a super
heart yet. Like probably, maybe,

51126870-83bf-4ff6-a279-31b8662b379e/7861-1
00:57:27.279 --> 00:57:32.590
probably something that's on my
To Do List is to look at areas

51126870-83bf-4ff6-a279-31b8662b379e/7861-2
00:57:32.590 --> 00:57:36.215
that have a lot of evaporate
deposits and.

51126870-83bf-4ff6-a279-31b8662b379e/7890-0
00:57:42.105 --> 00:57:46.830
I dream, I think during the was
it 2020 there was a earthquake

51126870-83bf-4ff6-a279-31b8662b379e/7890-1
00:57:46.830 --> 00:57:49.005
in Salt Lake City, I believe.

51126870-83bf-4ff6-a279-31b8662b379e/8015-0
00:58:35.805 --> 00:58:39.798
So we have a highly upvoted
comment by Alex Branch. Things

51126870-83bf-4ff6-a279-31b8662b379e/8015-1
00:58:39.798 --> 00:58:43.655
like another argument for
finally putting geology and do

51126870-83bf-4ff6-a279-31b8662b379e/8015-2
00:58:43.655 --> 00:58:47.581
it also model real and false.
The faction can be split by

51126870-83bf-4ff6-a279-31b8662b379e/8015-3
00:58:47.581 --> 00:58:51.777
messing up right versus sending
deposits, which can make some

51126870-83bf-4ff6-a279-31b8662b379e/8015-4
00:58:51.777 --> 00:58:52.725
good progress.

51126870-83bf-4ff6-a279-31b8662b379e/8059-0
00:58:54.045 --> 00:58:57.626
And I think we probably only
have time for answer one more

51126870-83bf-4ff6-a279-31b8662b379e/8059-1
00:58:57.626 --> 00:59:01.268
question. So I'll go to the one
by Lisa Challenger, which I

51126870-83bf-4ff6-a279-31b8662b379e/8059-2
00:59:01.268 --> 00:59:04.971
screw your votes. How could
current extreme weather patterns

51126870-83bf-4ff6-a279-31b8662b379e/8059-3
00:59:04.971 --> 00:59:07.885
impact models of potential for
liquid fraction?

51126870-83bf-4ff6-a279-31b8662b379e/8266-0
01:00:28.325 --> 01:00:31.935
Hopefully we'll succeed in by
the time my Mendenhall is over.

51126870-83bf-4ff6-a279-31b8662b379e/8274-0
01:00:35.475 --> 01:00:36.355
That's really cool.