WEBVTT
Kind: captions
Language: en-US

00:00:01.840 --> 00:00:04.720
Good afternoon.
I’m Jonathan Stewart.

00:00:04.720 --> 00:00:07.520
I’m glad to be joining
you by video today.

00:00:07.520 --> 00:00:11.440
I will be talking about
the GEER response

00:00:11.440 --> 00:00:15.920
for a potential future northern
California earthquake.

00:00:15.920 --> 00:00:20.240
So I am a co-PI of the Geotechnical
Extreme Events Reconnaissance

00:00:20.240 --> 00:00:25.016
Association, GEER. I’ll be making
this video presentation.

00:00:25.040 --> 00:00:30.000
Due to a scheduling conflict,
I’m unable to join you live.

00:00:30.000 --> 00:00:34.240
Thankfully, the live analyst from
GEER who is joining you, to whom

00:00:34.240 --> 00:00:38.640
I’m very grateful, is Robb Moss
from Cal Poly-San Luis Obispo.

00:00:38.640 --> 00:00:41.760
And Robb is a very
experienced of GEER

00:00:41.760 --> 00:00:45.016
and a member of
our steering committee.

00:00:45.040 --> 00:00:48.720
What I’d like to do in this presentation
is really two things – to tell you just

00:00:48.720 --> 00:00:53.840
a few things about GEER, for those
of you who may not be familiar with

00:00:53.840 --> 00:00:59.256
our organization, and then to talk about
some resources that the GEER team

00:00:59.280 --> 00:01:04.236
would likely use when they deploy
for an event in northern California.

00:01:05.840 --> 00:01:08.560
What is GEER?
GEER is a volunteer organization

00:01:08.560 --> 00:01:11.120
of geotechnical engineers,
engineering geologists,

00:01:11.120 --> 00:01:16.120
Earth scientists from a broad
spectrum of backgrounds.

00:01:16.720 --> 00:01:21.200
We respond to geotechnical extreme
events, like earthquakes, within the

00:01:21.200 --> 00:01:26.000
United States and around the world.
And we conduct reconnaissance,

00:01:26.000 --> 00:01:31.176
and we document our observations,
hopefully in a timely way.

00:01:31.200 --> 00:01:36.080
We seek to collect valuable
perishable data that can be used

00:01:36.080 --> 00:01:39.680
to advance research and
improve engineering practice

00:01:39.680 --> 00:01:43.088
due to the development
of improved models.

00:01:44.400 --> 00:01:49.280
As we do our work, we try to form
diverse reconnaissance teams that

00:01:49.280 --> 00:01:54.856
would have the required expertise
given the circumstances of an event

00:01:54.880 --> 00:01:59.040
and would have both experienced
researchers, established experts,

00:01:59.040 --> 00:02:01.600
as well as more junior
researchers who are interested

00:02:01.600 --> 00:02:04.029
in working with
reconnaissance.

00:02:05.200 --> 00:02:08.000
GEER is part of a broader
reconnaissance community

00:02:08.000 --> 00:02:10.856
that is supported by the
National Science Foundation.

00:02:10.880 --> 00:02:16.080
GEER is part of this
CONVERGE organization with

00:02:16.080 --> 00:02:21.576
seven different so-called EERs.
Of these seven, GEER is the first.

00:02:21.600 --> 00:02:26.480
It was founded over 20 years ago
and has responded to a large number

00:02:26.480 --> 00:02:29.840
of events. GEER basically was
the model under which

00:02:29.840 --> 00:02:33.096
these other organizations
were formed.

00:02:33.120 --> 00:02:37.600
Aside from the EERs, there is support
from the reconnaissance enterprise

00:02:37.600 --> 00:02:41.496
through DesignSafe Cyberinfrastructure
at University of Texas.

00:02:41.520 --> 00:02:44.480
And, among other things,
DesignSafe is the repository

00:02:44.480 --> 00:02:48.136
where our data goes
after our work is complete.

00:02:48.160 --> 00:02:51.920
We also are supported by the Natural
Hazards Reconnaissance Facility –

00:02:51.920 --> 00:02:54.320
RAPID – at the University
of Washington, which provides

00:02:54.320 --> 00:02:58.511
equipment and the
expertise on how to use it.

00:02:59.360 --> 00:03:03.680
GEER has responded to over
70 events during its history,

00:03:03.680 --> 00:03:07.120
and the locations are shown here.
You can see it’s truly global,

00:03:07.120 --> 00:03:09.120
and it’s not just earthquakes.
There’s a variety of

00:03:09.120 --> 00:03:12.202
extreme events that
we’ve responded to.

00:03:13.040 --> 00:03:18.456
Part of GEER’s work is
education and outreach.

00:03:18.480 --> 00:03:22.000
Back in the days before COVID,
we would do in-person events,

00:03:22.000 --> 00:03:28.720
either for a major event briefing
or to provide training.

00:03:28.720 --> 00:03:32.696
And this training would usually
be talking about strategies for

00:03:32.720 --> 00:03:40.294
conducting effective reconnaissance
and hands-on equipment training.

00:03:42.000 --> 00:03:46.160
Of course, we also do online events,
especially for the last few years –

00:03:46.160 --> 00:03:49.280
webinars and workshops,
again, related to

00:03:49.280 --> 00:03:53.334
a particular earthquake
or more general training.

00:03:54.160 --> 00:03:58.000
We also do joint training with our
sister organizations, RAPID,

00:03:58.000 --> 00:04:02.560
DesignSafe, and CONVERGE.
And we have sponsored

00:04:02.560 --> 00:04:06.102
special sessions
at major conferences.

00:04:06.800 --> 00:04:09.920
Now, the second part of my remarks,
I just want to comment on some of

00:04:09.920 --> 00:04:15.440
the resources that we would likely
use in a team that is responding

00:04:15.440 --> 00:04:17.600
to a northern
California earthquake.

00:04:17.600 --> 00:04:21.256
It would be much the same for a
southern California earthquake.

00:04:21.280 --> 00:04:24.240
One of the most basic resources
we would use anywhere in the world,

00:04:24.240 --> 00:04:26.526
actually, is the
USGS ShakeMap.

00:04:26.526 --> 00:04:31.280
It gives a very rapid sense of
where shaking is stronger and weaker.

00:04:31.280 --> 00:04:34.936
So here’s one for the
Loma Prieta earthquake.

00:04:34.960 --> 00:04:42.320
A tool from USGS we’ve been
using recently is the near-real-time

00:04:42.320 --> 00:04:45.976
liquefaction map using
liquefaction geospatial models.

00:04:46.000 --> 00:04:51.120
And these models provide liquefaction
probabilities, which are marked

00:04:51.120 --> 00:04:56.320
over here, with hotter colors
indicating higher probabilities.

00:04:56.320 --> 00:05:00.160
And you can basically overlay where
you actually see liquefaction effects

00:05:00.160 --> 00:05:05.680
on these probability maps, and this type
of result is, I think, increasingly going

00:05:05.680 --> 00:05:12.536
to be featured in future GEER
reports, for earthquakes anyhow.

00:05:12.560 --> 00:05:16.400
Now, one thing that’s particular to
urban California – the Bay Area

00:05:16.400 --> 00:05:20.080
and southern California –
is California Geological Survey

00:05:20.080 --> 00:05:24.240
has maps of zones of required
investigation for liquefaction

00:05:24.240 --> 00:05:27.200
and landslides.
Also surface fault rupture.

00:05:27.200 --> 00:05:30.320
So you see here, for example,
the green are liquefaction zones.

00:05:30.320 --> 00:05:35.559
The sort of darker
brown are landslide zones.

00:05:36.320 --> 00:05:43.520
And these would be an extremely
valuable resource to a team that

00:05:43.520 --> 00:05:46.880
is deploying into the field
because it’s where you

00:05:46.880 --> 00:05:50.327
might expect to see
these different hazards.

00:05:51.360 --> 00:05:57.656
One of the things that we do very often
in recent reconnaissance exercises is

00:05:57.680 --> 00:06:03.096
conduct detailed reconnaissance in the
area around a ground motion station.

00:06:03.120 --> 00:06:06.400
Again, if you think about the fact that
we’re trying to use these observations

00:06:06.400 --> 00:06:10.880
to support model development in
the area near a ground motion station,

00:06:10.880 --> 00:06:12.779
you know what the
ground motion was.

00:06:12.779 --> 00:06:15.736
So it’s a better case history than
one where you don’t know it.

00:06:15.760 --> 00:06:22.296
And so we have these locations.
It’s saved in NGA relational databases.

00:06:22.320 --> 00:06:24.000
And these would be ground
motion stations that have

00:06:24.000 --> 00:06:27.280
recorded past earthquakes.
And so this is the type of information

00:06:27.280 --> 00:06:31.736
we would certainly send with
a team going into the field.

00:06:31.760 --> 00:06:36.720
And then the last item I’ll mention,
which is a fairly recent one, GEER has

00:06:36.720 --> 00:06:42.056
begun working with the NGL project –
Next Generation Liquefaction.

00:06:42.080 --> 00:06:47.920
And, in this collaboration,
we can take the NGL database,

00:06:47.920 --> 00:06:53.096
which is a database of case histories
of liquefaction, or non-liquefaction.

00:06:53.120 --> 00:06:56.240
Each case history has,
of course, a location.

00:06:56.240 --> 00:07:00.560
It has an observed field performance.
And it has geotechnical data,

00:07:00.560 --> 00:07:04.720
among other things.
And, by re-occupying these sites

00:07:04.720 --> 00:07:08.880
where there’s been prior observations,
we can really learn something about,

00:07:08.880 --> 00:07:11.440
you know, what kinds of
events would trigger liquefaction

00:07:11.440 --> 00:07:13.416
and what ones would not.

00:07:13.440 --> 00:07:17.200
The map here is a static image,
but in the – in the real database,

00:07:17.200 --> 00:07:21.280
you can zoom in as much as you
want and see rather specifically where

00:07:21.280 --> 00:07:26.616
different observations were made
for the case histories in the database.

00:07:26.640 --> 00:07:28.400
So, with that,
I’ll conclude my remarks.

00:07:28.400 --> 00:07:32.985
I appreciate your attention,
and I wish you a productive meeting.

00:07:34.600 --> 00:07:39.599
[silence]