ICLR Friday Forum: Linking strain and seismicity for earthquake hazard estimation (Nov 2012)

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thank you.
Well, anyway, it's just from Environment Canada, a hybrid store number joining us today, discussing her research in the booth.
Just go.
So, I actually I'm going to start by saying that the title is kind of completing Originally, I was a lot of time talking about you have measurements, deformation, changes in motion in eastern Canada.
Very new and interesting work and how it hasn't over.
Some events have superseded that talk about other, like the B C, which I will touch on and and seven kinds of going to prison in Italy.
Theories on that.
In a brief outline, I will finish with, um, uh, work with work on deformation and earthquakes in eastern Canada.
And I will cut on that, but more time, probably on the other again.
Thank you for attending.
And thank you for having me.
There are a lot of fun for me, and then I'm gonna start by talking about what earthquake is, what we know about it.
And then when I move into earthquake forecasting of it and thats we'll talk again a little bit about that.
And I'm not finished with nation Canada.
This, of course, is the Haitian quick is we know that it killed 1000 people.
Damages I like to show to talk about this.
Like when I talk about this quake hazard, because this early, into the intense January 12 not three months later, we had a quick of the almost exact same magnitude.
Magnitude seven in Southern California just felt in San Diego and it killed nobody.
And as a matter fact, most you probably don't even have mostly art respect times probably never even heard of.
Or remember the Eastern earthquake of 2010 in California and the reason that we can prevent it, we can prevent death.
But we have to have do that.
And we have to know a bit more about what those risks are in place courses the quake of 1906 I use this image with my students in, uh, natural passes on how the earth moved.
And of course, we talk a lot about you, and I'd like to point out to them that the great terrific was supposed to occur before this when I was a teenager.
I don't tell them how many years ago that was because they wouldn't be impressed.
I know that I was told this was certainly happen again before the year 2000 that we would see it again.
And of course it happened happened because we aren't really all that good at forecasting recurrence when how often the large events occurred.
Um is easy and maybe even to get a good average on that.
But the variation in that average in a lot of variability.
So we could say the non average earthquake occurs every 100 or 121 150 years.
We may know that the average number we may know that pretty well, but the variability on that 100 years could be as much a plus mine.
One.
Yes, forecasting Earthquakes are predicting that good.
This is the friend I was quick and tsunami of last year 2011.
And again, this is approximately a magnitude nine progressive.
It's still, but it killed 20,000.
We know that the tsunami killed most of those people and caused we want to think about forecast in half.
We know a lot about you won't know about, has a map.
We will use them, but and has a Messer are an exceptional tool.
I feel kind of looking to build a better has exceptional tool for planners.
Engineers for building codes for building police don't fall down, but forecast is different.
Forecast is gonna provide you a probability of an earthquake occurring at a specific location over a fixed period of time forecast.
In very in time, we could have a forecasted a matter of days a week.
Short term forecasting.
We can have forecast that are a matter of years, tens of your spot years or tens of years, 5 to 10 years.
Or we can have four cats which were effectively again.
I have a map which are really a your time frame.
Historically, many attempts have been made to do earthquake forecasting.
However, today we are as close as we ever will be.
And the reason is that we, in my opinion and the reason is that today we collect more information about where and when they occur into small event.
We used to rely on forecasting be done using large man.
We would say that we know how often a magnitude six occurs.
We're gonna look for particular kinds of signals before that magnitude 78 and we are going to then try forecast that very hard to do, and it was extraordinary.
Unsuccessful, because we have very foreign statistics.
On magnitude six, we have very poor statistical magnitude seven or a magnitude eight because they occur so infrequently.
However, we have lots of information about magnitude three of them because they had personal office, they incurred 100,000 more often, then a magnitude five for that, so we can collect a lot of statistics that we can use.
Those statistics tell us something about earthquake forecasting about when the next picture likely example of that again, we could be record today, 500,000 earthquakes per year worldwide and 10,000 in Southern California alone.
Those air small events, not nobody feels.
But I'm gonna say this again that most of those small events are going to be used as a sensor for the larger events that are coming.
We're gonna assume that those small events are telling us something about the underlying seismicity there, acting as a Spencer underlying strips.
They're acting as a stress sensor.
They're telling us where stresses are increasing or decreasing.
It's not a simple problem is a complicated list, but it's the first order of zeros order effect, you can assume that says misty rate changes.
Changes in the number of events we have are a reaction to changes.
As a result, we're gonna use those to suggest where upcoming events might happen, because those also react the same stresses.
It's just that it takes so again.
This is a forecast map we made over 10 years ago.
Now it was the forecast earthquakes from 4010.
That's the one on the left and, um, again grid again.
It's like it's the forecast.
Raising magnitude five from 4010 and all those red and orange and yellow lots of locations where are expected to happen over the next 10 years.
And you look at that map over plotted on it all.
The earthquake off magnitude five graders have happened in the 10 years following 2000 and you will also notice that there are only two number seven and eight there.
39 place on that plot, 39 races and magnitude five, and all of them are on or near the national air.
We specified, which was, incidentally, 10 kilometers, so within 10 kilometers they all fall within one of those That's not bad.
There's a fair number of false positive, the problem with anyone.
And yet with any respect for casting technique, this or any other is the issue of false.
Okay, you're always gonna forecast some earthquakes that never and you can see that we do have a relatively high false positive right here, about 20%.
But you'll also notice that again we only have two misses.
But in addition, there's a very large part of that map which we say there aren't gonna be.
And that is a benefit to a method like this, because it can tell you where you need to put your resources in the next 5 to 10.
Where should you be upgrading death?
Where should you be reinforcing your schoolroom?
OK, where should you be doing those kinds of things over the next intermediate with intermediate term over the next intermediate term?
And again we think that this was reasonably successful.
If you look at it from that perspective on the right, you have a had a map of the reason for this up again.
What engineers used to build a building with probability exceeding a certain acceleration due to gravity.
And again you'll learn that there are lots of colored areas on.
This is what we use for building codes.
This means that sometime in the next 50 years, there's a 10% chance that Los Angeles good experience and acceleration a jump that's about 80% of 10% chance that in 50 years that's what I would tell you that I So the real issue there is.
What they use it for is used to build buildings that would fall down when that eight, when that 80% of grabbing holds up its building code record.
So this is again that's saying that outline what we've done here and to remind you that what we want to do here is what we are doing here is assuming again.
It's that first line that's most important, that small earthquakes are acting in the centers for the large events.
Acting's a center for the stress changes that occur prior to the large events.
So again, to make this map, we only use earthquakes of magnitude three and above.
Okay, so again, we used there are approximately 25,000 or so that occurred in the last three that we have recorded, I should say, in the last 30 years in California, Magnitude three in a bus.
That's what we use for to create that.
Yet Christie published this prediction back here, too.
Today we submitted it in two dozen.
Didn't actually make press into 2002 huh?
Commentary on publication In today's world, the last 12 years have changed.
So, um, I have learned a lot over the last 10 15 years.
Um, for California, I would change almost nothing.
It turns out you have experimented e I have experimented with other separate using magnitude to about you don't gain much.
So I looked at the information that you get from using different, uh, different magnitude.
Different scale, different sizes.
Way we've been these down into a grid, for example, about 10 plumbers to help.
It turns out there are looking at other no nothing.
I've changed up nothing anyway in California.
What I have learned is that the first probably I have learned, although looking in other areas like Canada, is that is that there are a couple of things that matter a lot here.
One is that you need to be collecting data pretty completely If you have holes in your data, that's it.
Strictly a database estimation technique.
So if you have holes in your data, you won't do well.
For example, the reason we have to Mrs number seven and eight is because we don't collect data in the so the networks are sparks with Finn on the coast, and that means we didn't collect.
We don't we haven't collected enough data.
Allow us to properly look att those areas so that something has to be done if you can actually published.
This really isn't about the public.
You would include in an error estimation associated with what your network coverage looks like.
Second, I have learned that in some places like eastern Canada, which arm which arm or slow moving than California, which which tectonic rates are much slower, the plate motions must lower.
The stress rates are much lower that you have to you larger, larger been larger areas and larger times that to really see anything.
But I learned that the Taconic area makes a difference.
You have to tailor it to the particular physics, but other than that it hasn't know significantly changed much.
What about like Sandra strikes that time generation.
What about that?
Versus subduction?
Like, you know, I guess there's different nuances in terms of having smaller quakes.
So there again in place.
But I had a student who did a lot of work with Taiwanese catalog, for example.
And in Taiwan, you could do quite a good job of this.
Well, two problems with abduction, but I want you to quit a good job because the data is again pretty good.
You don't have to use magnitude threes.
They produce enough events that the smaller the magnitude you go, the more noise you get that will be that good at collecting small, small data, small magnitude it and get more noise dropped on smaller magnitude.
So in Taiwan, you're better off collecting up.
They have enough earthquakes of magnitude.
For that.
You're gonna do this with a magnitude.
For me is one of the things that the other problem productions noisy because a three dimensional, so so the conduction.
Don't look at it.
This is a two dimensional map, right?
And in some ways, like Taiwan, you have really have to do a three dimensional map.
Which student isn't against a job with it in someone like Western Canada.
Our problem is that we don't collect.
We don't have enough networks networks out over the ocean subduction plate.
And as a result, we don't collect data from deep enough yet to do.
There's a lot of errors, a lot of Miss data with death in Western Canada and that one of the problems with deductions on it you're gonna have to do is we're gonna do this on a regular basis of a place like that.
I have to have better that.
Any other questions?
Yeah, well, just maybe in terms of the GPS technology and there's even a cougar can Japanese at all these GPS readings of pressure build up in that seductions?
Your place?
Another staying.
The second biggest area buildup is off the northern Island.
Sapporo.
Is that normal?
Like, how about that technology in terms of forecasting, using GPS technology, actually using GPS technology at the end of the talking you want, uh, maybe a little.
There was a whole different topics.
This is a forecast.
That expression is to pull, I think, um, back in 4 2005 This is the forecast I did back then.
This is actually Excuse me.
You know, points on the, um top.
Matt is noisy again, using some of the techniques I learned I d noises for the bottom one is much less noisy.
And the math we've been using the technique and the massive been using based in Canada ever since.
You could see in general again the Blue circle show you locations of earthquakes that were forget that occurred after the forecast started.
The yellow and orange again are our forecast locations, locations where was forecast and again interestingly again, there's the location of the Ottoman earthquake in 2010 and we do a forecast that correctly as well have a more Children that anybody wants to see it.
But I left out of this talk, but we do forecast that auto quite well.
And we also again produced no false negative except the one and Husbands Day and that one in Lake Huron and Georgian men.
And that one occurred that scenario where again, we just don't collect anything we don't have.
Until very recent years, we haven't had networks up in that area, so we don't have a good record.
There is about it again.
Wouldn't missing about 12 Quick, which again is about the same rate we're getting for California.
2 40 Nothing.
12 again.
This is just a discussion of where we are today, with those mass produced 10 years ago.
And I like to tell people that 10 15 years ago, when when those mats were produced, we were told we went to publish it.
You don't want to do that.
Nobody forecasters done.
And now, today, 12 years later, there are actually agencies and organizations out there that not only take our forecast, but others based forecasts of other forecast techniques used the same idea.
Small earthquakes tell us something about fingers.
They made you the mask differently, but that's a possibility.
They used the same principle.
They're gonna use that seismicity data to make their own four cats and their Intel agencies like the Collaborative for the Study of Earthquake Predictability out in California, which actually evaluate those forecasts one against the other.
Now, enough of the mouth that you can't even put together a group of different forecasts and see which one how they perform relative to each other.
Some people get a contest.
I like to see that as an opportunity to need to figure out which ones are doing better.
And then why that better?
What?
What's different about them that makes them better Halfway improve all.
Not everybody needs that.
Is there a possibility?
Ensemble?
There are two possible ensemble modeling in this.
Wanted to do yet to stack them all up on average amount and tried to sometime like there's actually a model that was produced statistical models of larger over a couple 100 years.
And then and do these techniques on those and compare them to potential.
Yes, there is.
Yes.
Did the U.
S Geological Survey start were active program on forecast?
No, I would say that the U.
S so the U.
S has really hasn't done anything with forecasting.
A number of them participate in this collaborative, which is run by the Southern California with Quick Center, which is affiliated with us.
But us, You, um they run this predictability study and there's no worldwide actually group that doesn't say anything, but, um, the U.
S.
Use themselves not taken part in that.
Say they're none of them.
Come to the meetings and talk and discuss this little formal program.
I will talk a little bit about that possibility.
A couple.
Well, Tom Jordan was just Lucy Jones.
Actually, that's appropriate question, because Tom Jordan effectively is the head of the Southern California center.
Lucy Jones was the head of the U.
S.
G.
S for many, many years.
She's a woman, effectively Bob for the great shakeout.
California published a paper a few years ago in one of the leading journals that basically said gave you that second statement did other than suddenly considered earthquake forecasting things like geodetic medicaments and electrical signals signals.
But so far none of them has qualified at a good forecasting technique.
And I have have terrified praise their course.
The our focus, focus.
Almost all the community that doesn't like forecasting today is on community based methods that are enabled by high performance.
Exactly what I told you.
They publish that in 2010.
This exponential increase in data has allowed us to do do what is the basis for our method and what I really think.
It's the physical basis for all of these messages.
And that is to say that seismicity is some measure of stress.
So we're actually gonna try and think about it, and I'm just a little bit about Operation Quick forecast because that's directly related to this idea.
A lot.
So for that problem with a curtain, the club with a quick predictability again look at the base methods tried to prepare them.
Um, they also believe that that agency exists over looked at.
This agrees that short and intermediate term model demonstrates some probability game how much that is still up for arguing.
But there's some probably gain some information you're getting in forecasting future relative to the long term time Independent hasn't so those we call the time independence 50 years, their constant over that 50 years.
We're talking about some kind of time dependent model that you could update on a regular basis.
That's what an operation was with.
And the goal is provide the public with considered useful information on that time dependent size and the challenges associate with my pain.
The real impetus behind what's moving that that program forward today is the lack of nine so that her book occurred in April 2009.
It was a magnitude 6.3.
Italy is subject to earthquakes of this, not not an unusual occurrence there.
They're not rare.
Events on day almost always caused a fair amount of damage.
In this particular case, there were 300 dead, $2 billion in damages, 20,000 buildings destroyed, 40,000 homes people.
How many did you could see?
The sheer magnitude of that devastation?
Howard was a problem here.
Another 2009 before the earthquake occurred from almost January on seismic activities increased.
They had what were called foreshocks or swarms swarms of smaller events, but that people could feel okay and that worried them.
Now again, Italy is prone to swarm.
This is not an unusual problem.
Many of those forms occur and no large earthquake occurs afterwards.
What didn't help the problem was there was a technician who works for the local laboratories who liked to make those traditions thanks, save some rain on emissions and certainly rate on the missions have been studied in the past, especially with earthquakes.
The reason We don't have a lot of rain on mongers out, too.
Look for a quick look for precursor to potential like spikes and right on gas before the earthquake occurs is that rain on gas will be released by a lot of things like high rainfall rate on is effectively something that's absorbed in the groundwater.
And so if you have changes in water in the ground water, the local water table, you can have changes and right on to get it off a lot of false positive.
Nobody considers a reliable method forecasting, however.
He did have his instrument and you like to do this work.
And he issued predictions and even evacuated the school, I believe, and they they were almost all false alarms.
He did again predict one before the earthquake happened, but the earlier, too, were false alarms.
But again, there was a lot of widespread National commission for the prevention of, UM, predictable protection issues.
Studies there was supposed to, and they study the possibility of any larger quick, and they came out with a statement that said, There's no reason to say that low magnitude could be considered for castrating strong event in an airport Large event did occur.
A year ago, seven other experts were indicted on manslaughter charges for allegedly failing to warn residents Traditionally before that, we settled little in 2000 and nine.
Now I like to point out there are two problems with to leave.
But I think what is that?
It is general government policy to state that is not possible.
You go to any website for the USGS, they will tell you that.
OK, it.
Despite the fact there are agencies and people who do do this believe that there is some probability gains of information to be gotten.
Something I think that we have, they do that, in my opinion, is because once they say that publicly, they will have to put together a program to do it.
And that's not an easy job.
I'm incredibly sympathetic, Okay, I don't want I don't a lot of the public and tell them where when I think earthquakes are going to occur because communication with the public is not my The last thing I want to do is cause a panic or cause the average human beings house prices to go down okay or anything else that, you know, things have happened in the past, so this is a big concern of government.
They need to figure out how to communicate that risk in the proper reasonable way so that the correct behaviors occur on the public by the public, and so is results.
They generally take the policy that there isn't any real way to forecast respect.
So therefore we don't know anything.
I would say again, I want to hear what the judge said about him.
He's basically felt that they were give possible thing.
They gave in exacting, completely contradictory information.
And it's certainly true that they did not communicate again properly.
They tried to reassure the public rather than give the public reasoned information, and I think that was a mistake they made last month.
Those seven were convicted and sentenced to prison, Um, in Italy and I would say that I think it for my personal view.
People act the press before.
I think that quick forecasting is incredibly difficult.
We're told all the time it can't be done and therefore to convict people who were trying to do the best they knew how at the time, and put him in prison for that is is that fair?
But, um, again, also in LA Cola and I didn't have 300 die, So I have to say that you like we're pretty far away.
See that what really happened?
We know that four trucks are one of those problems that have long been recognized and study study.
This potential swarms foreshock, small events which occurred before big events.
We do know scientifically that there have been places where we see those.
Hey, where were you after the fact?
When we go back and look, we see that there were four shocks.
They do not occur all the time.
They also are very hard.
They're particularly pretty before you can see a form.
But until that big event occurs, you don't know for sure that itwas they were precursors.
They were a four shot to a main shop, so you never know with certainty before they happen.
We know that less than half of the larger quick study date had detectable for shock, and less than 10% worldwide are followed by something larger within 10 kilometers in three days.
So again, it's a very hard forecast to make when you're sitting there in Italy, seismic forms are relatively common, and they haven't very very often, and there's no larger like afterward.
So again they hadn't really taken into account the statistics.
But the offense that even if they had said there is an increased probability event, they would have said it is a small percentage increase, 1% less than 1% a couple of percent.
Something on the order.
There's an increased likelihood, but that increases is very small.
What the public would have done with that what what might have been.
None of that would have been thinking like, um, uh, make sure your emergency kids make sure you've got water.
Make sure you've got a charge cell phone.
Make sure you've got a radio.
I'll make sure you've got canned goods.
Those kinds of things are what should Nobody would have been evacuated based on that, even on that kind of, Even if we've done been able to do for Captain, we certainly think I really think that that forget consistent with this understanding was not communicated properly to the public.
And and then the other problem was that there were all these amateur predictions out there.
It's a raid on gas prediction out there as well.
That doesn't help the communication process.
It only confuses the public and make some more work.
The point here is that operational looks like forecasting is gonna be done properly, is gonna have to quantify the increased probability and how you communicate it again.
Most modern societies mandate requiring some way that the best available, available science used made quick hazard.
If that means there's a sum like this, there's a possibility that you could provide more information about the near term, intermediate term and long term seismic hazard.
Then you should do that again.
Mo.
People don't use most governments don't use seismicity base forecasting techniques.
Thio add to their information.
Get the information they have on the quick.
But we think that that will change.
I think I think it's gonna have to change.
For example, the USGS has proposed a program prototype operational quick forecasting in Southern California.
This would be along the lines of watching the committee as it developed and then issuing figuring out how to issue warnings which were something like There is an increased probability in the next two weeks, a 1% increasing the probability of quicken the next two weeks, something like that.
It would almost certainly be short days and low, probably again on the order of 1% the short term forecast.
It is very difficult with short term forecasting to come up with a higher probability, you can look out to the 3 to 5 to 10 years.
You can do better with your probability.
You can do better with your increased, but because there's such a variability in in inside missing because the numbers go up and down so much than the actual probability gain you get again.
This is that for cash for Toronto that I told you we did a couple of years ago.
This was a five years I got out of a human standing in trucks, and so again, and you can see from the Green Star.
That's where the Ottawa earthquake occurred.
If you done about again 2005 and again, you can see this again based on improved data, improved ability to clean the data the last few years.
But again, you can see that there's increased red squares or increase probability and the probability that for all the way out of ST Lawrence, you're Ottawa Montreal.
But we do want to think about mitigating loss and count in Canada.
We have to think about where those gonna occur near our biggest city.
On the right, I show you a plot of the thank you.
Contribution to seismic risk in Canada from urban centers that uber its first Montreal There are significant, probably for earthquakes of magnitude 56 in Montreal, and it's an older city with older infrastructure.
The actual damage that wouldn't that wouldn't would not be small.
Your majors and the map of the left shows my guys did in 2005.
Eastern Canada Update is to be part of the updated seismic for Eastern Canada.
Maybe, maybe already.
So again, you can see this is again an acceleration, a massive of spectra acceleration for, um, Easter can all done Christie Big City.
Although it has greater, greater PGA, it's also because no one lives around there.
That's all about all that all about.
Okay, I would I would help again a lot more people there and there's significant hasn't in Ottawa, You see there and again, uh, Toronto has must let because there's less seismic risk here.
But that has about almost the same because it's closer to the center left.
This is the result of the micro Donations study in Eastern Canada, done by various Mona's A D in 2010.
Many public This is where we go out, we try and figure out what is the ground conditions.
You wanna know how these earthquakes or what kind of damage that's gonna cause you got?
You have to know what the buildings are built.
Ground shaking is a function not just of the size of the earthquake and how close it is.
But what kind of soil?
That building sitting up.
So these Air Micro the nation that he was trying in which various studies, the ground conditions all over.
Okay.
And we are working on those from Montreal and this is an early results from words by the same project to Canadian Research Network for Spectra acceleration in Montreal.
From those micro donations you can you can make after a potential ground shaking this case, this is peaks acceleration for self defense in on the left and on the bottom is thes values have changed over the years.
We've collected more data shows here that 2012 11 Pete special acceleration is actually gonna be lower than we estimated.
That measure major changing right now.
A lot of it is additional data choir again.
I need it acquired on the ground about Have you seen that brand new research about a week old big grand attenuation much farther.
And that's never not a surprise.
Really resemble in when the new manager what occurred in the early 18 hundreds of here?
Um, Thea uh, the shaking was felt.
That wouldn't happen.
A bunch of the ground the harder around hard rock type is passing through.
That's a first.
These are fake maps amendment.
So this is, for example, from the class for good now called the stable for now.
But I spent a lot of time as a child.
I was in jail time.
We felt that emotional.
When this occurred in 2002 it was a magnitude five and again northern Vermont, well on the New York side New York Vermont border starting and the colors colors.
Here are the intensity How much shaking was possibly a intensity five, which meant that people were shaken up pretty good.
That would have been some damaged with significant.
And, um, this is an actual shape now, okay, from it was pretty some matters, but the goal of my research with Gail and people of various to take those locations of future events that I create that I've come up with from my forecast and then make virtual or estimated theoretical shape map for places like Montreal using the information that Gail absence has been the commission has about how the ground response to those and, um this, for example, is the location of potential place but hasn't quite locations near Montreal for the title.
Um, I did this actually, um, possible locations or sex of locations.
And what I don't know in what really isn't here is that we think the largest events that might occur of those which were strung together.
So if you Yeah, I do.
So if you look at this here, for example, and this set here, we believe that these are the most likely locations to string together to a larger events string needs together.
And these, well, these, we think are either noise or simply small, isolated events which will not turn out to be larger and more damaging.
And Family module was here his closest to these two at their largest.
So the idea is to take these two next, create rupture model again.
Using my technique, I created potential rupture mall over potential size actual vault links that might be associated with these again.
Mike look probabilities, how likely they are to her.
That's a different question.
But if they heard in the next five years, it is.
If they could next five years.
We think this is the likely size again.
Wait is directly related to magnitude.
So you can take these guys, these areas, the actual facial length of these faults, and you can estimate what the magnitude is that it will be.
So you do that and you've got to create, in theory, a shake map.
It looks like from here a shake map for Montreal that would look like this based on the others.
How what kind of shaken up would you get it The way I was student this week?
Doing that was unfortunate.
She's not finished finished before she showed up here.
I hope to show it to you, but she's working on those now together for a poster I'm getting next month in December in um, presentation of the conference there to show what kind of ground shaking we would get in Montreal.
They if this was actually happened in the next five years and of course will associate a probability That brown shit.
Let me be the first time we met.
We've done that for you.
Actually, we've done that anywhere in the world.
This is the map you can see of all historic large events in eastern Canada.
Um um again, the 72 Grand Banks event in 1929.
We know that there's been 5.56 point two against the 5.9 dragon event which happened out here again.
These are all off concern.
And again, these relatively large 9 to 5 and above trust events which have all occurred here in Montreal and again are in locations associated with those two that I just showed you.
This is the Queen Charlotte Islands over number 2012.
It was about a man to 7.7.
It was a trusted in that, actually, it has surprised much of the faulting in the Queen Charlotte's in strength holding old.
But the nature of this thrust event, I think one of the reasons why there was not initially concerned about a tsunami again tsunami generation isn't as expected from this part of of the Western coast as an earthquake.
Down as the automatic response quick down by the cove.
I would this recruit her down by the river island?
We would have been community would immediately looked at immediately would have been much more concerned about the possible.
It's not that they weren't concerned.
I don't mean to say that, but probably I cannot say, Of course, what people were thinking at the time.
But I think it would be wise to the public.
Um, this is a forecast.
We used up all Kylie before this one.
I apologize.
I have not.
I could not find my hard drive this morning.
Um, the mess I have with the actual geography on it.
Coastline of it.
I do have the moment.
The way we did this in 2004 night gave this talk.
I think that following here, here in the in this particular workshop series this is a map again, a potential seismic locations.
And this is the noisy nous that I talked about associate with production.
So I am, you know, full disclosure here.
I didn't come up.
I didn't cut this so that you feel the noise.
It is noisy and deductions on.
That's the reason that we're stacking a boulder with with death.
So in order to do a proper forecasts, using you really have to do in three dimensions.
And look, it slices through all of these so they clean up.
But when you get further up north, you don't have a conversion.
Two more strikes, the regime or something more two dimensional like California.
And you don't have that noise problem in the north.
And so again, this is the location of that 7.7 Queen Charlotte Islands earthquake in October.
And you can see we did accurately forecast the location of that here.
Even with this two dimensional retorted, this is the island.
No.
Go back.
What, um, tip of the island like this?
Yes.
Thank you.
Victoria is down on the bottom here.
So they wouldn't.
It would be, if I recall correctly, you talking about presented here about the forecast Waas Exactly where your great king and then you were less concerned over the years.
You?
Yes.
That's exactly right in the laboratory.
We see, um, this particular model shows that this sort of variety of events here these will change as I do this every year or two.
A king and the data accumulated.
Um, he's not move around.
It has historically found that moving anomalies usually mean not reliable, not any persistent sizes in one location that's telling us this stress change.
Building up.
Um, so while there there's always concern it resembled a place like Delta Richmond, there hasn't been any persistent suggestion suggestion that there's a persistent locations here.
We go back to teaching Canadian side again.
Just a show you one more time with the lines up again between Ottawa Montreal, and they're here to the North Pole.
Um, I do that because I was gonna talk a little bit just to finish about what time?
Just finishing GPS velocity.
So we do actually record.
Um, we have a network that records GPS.
These are the stations here.
They're not all extra counselor in the US and everyone you can put these together and you can create a map.
Nice clean map when you do.
A lot of work on that paper was a lot of work.
Which shows you, um, the horizontal motion did not relate any head.
Everything that's not related to the plate plate Motions attracted the horizontal motion in eastern along the eastern seaboard, Eastern Canada like way believe, probably do the up up the uplift, associating with the place.
That's the big signal horizontal post.
So this is not up signal could get that very easily.
That's big.
This is small, and it's hard to get out.
And this is really the first publication that suggested a clear, coherent, and you could actually pull this for the GPS emotion out.
What?
Pretend up.
Pull that.
David Eaten once told me that they believed that most of the rebounding well, maybe compared to what it used to be.
You still get as much as 68 millimeters per year from I should say that some GPS you can create what we call stream out.
This was created by the middle of 2012 in California.
Not, um, can.
And this is actually hard, pretty hard to do.
This is the first time anybody ever used GPS data use GPS, so vector data to create a map of what the deformation field on the ground ought to be.
How how the ground is twisting and turning as those plates.
Yeah, and again, it's not a simple calculation.
Do we know about our map from this and did the same thing.
So we created a whole strain map for mass here on the bottom of how the earth here in Eastern Canada might be talking, twisting and turning as a result of that GPS.
Now, my post op, who actually did this would like to remind me it's not very much needed there, and there's not really enough years.
So he needs a lot more work.
Probably Phillip Fremont error.
Okay, but again, pretty excited.
You'll see that we could do it.
And season in general, you could see that that train doesn't match up pretty well here along the Ottawa Punctured Robin.
And all this, Mrs Just this thing that occurs between Ottawa Montreal course again, Just a bit.
You need to the east, into the north and then up the ST Lawrence.
You see that some of that value is higher here, where you wouldn't expect it to be against The ground is moving in response.
Miss Agnes is occurring in response to the whatever is making the ground toward.
But they're related to each other.
And you could see that for the first time, this one here is a knifing in the most unreliable to the edge of that network.
If you remember that GPS network that we looked at show you.
Do you remember this is down here is the engine that network?
And so it is.
This may just be an edge effect from the capital.
I'm not sure that this is a true thing.
If you wanna met enough, I could make a map of seismicity rate changes with the p I anomalies that I made before I can make it to scale using magnitude four and 9 to 3, just as I did earlier.
And if I plot goes up against this, Okay, you can see that, For example, I get that same long wavelength pattern running north and south again.
I just cleaned of it running north, northwest, southeast between Ottawa and Montreal and again, in this case, I made a score.
I don't get this anomaly here.
I get a small one here still, whether this is either as big as it appears to be here or if it's there at all.
So we need more data.
We have new GPS, relatively new GPS stations, which I've been collecting day that here in the Toronto area over the last six or seven years and that we will add in that.
You see if we could actually get a better what we believe be a more accurate.
So this is, of course, within the North American plate.
Feed your inspirational reading regular decompression from the glacier and potentially associate it straight on what people generally reason we see back reason we see all this here is because there's some kind of weaker area here, so that, you know, there's a lot of a lot of movement going on at the end of the plate.
A lot of pushing and shoving, instructing, straining and shoving the engines of the place.
Eventually, that all kind of get transferred to the center of the blade.
I mean, it's a big thing.
But eventually, over time, some of those dresses work their way, tunneling into the into the plate itself to the center of the plate, and the way we do sometimes get a few big ones like the new Maverick Quick, the early 18 hundreds, for example, or moderate sized events, which we get here along, um, the ST Lawrence Seaway.
Many people believe that the ST Lawrence Seaway is a relic Um, week film, a relic expansion or resting area in the relative risk area that occurred under one of the old plate tectonics.
Things they pull apart and crash together, pull apart, patched together.
So it's an old, weak zone and that the earthquake cluster there need to occur in orders or relieved the relative motion.
The place of the edges, they again.
Are they clustered in me?
There is because that it's a weaker area, right?
And some people and double down by new matters.
That is actually what's called the real foot risk there another what they think that didn't didn't finish or got back together again in one way too much of a technical term.
So that's, of course, within a plate, explaining now, taking the technology for, Let's say, Western camp with Japanese example right get in terms of So what?
How far we'll probably we've seen California map, which, which is a detail.
We actually look up gonna magnify that.
Figure it out.
How close are we doing that?
So I have to say that I haven't thought with colleagues.
I know out Western Canada.
They do some of the finest work in the world.
They have some of the best quality and, well, what they're universally admired for that work.
They, for example, from identified with now called episodic tremors.
Um, for the first time ever, because they, um they were the first to ever see that because they have that exceptional TV network there.
The biggest.
So the biggest stumbling block to read a map like this out there is a number of stations and how dense they are.
So here you look.
But if I look back again here we have com effectively 34 stations 34 30.
A couple dozen stations here in eastern Canada.
And I told you that as it is vicious, you have to take that.
That's maybe not quite enough.
Okay, that produce a nice nearly a person can't get anyone.
Here is what they do in California.
They have a similar problem on the West Coast.
If you want to produce a dense strength, you have a fair number of stations and, um, and a particular density of stations to get that and that that currently doesn't think so.
Well, at least not probably to the now, If you wanted a longer spatial scales you could certainly produce something like this again.
How accurate would be that they would be much more.
They would be much more expert in telling you that answering that question the, um uh, bigger, more interesting thing out west is that they certainly do a good job to look for, uh, rate changes.
Changes in how fast place we're moving to help pass The plates are moving relative German, whether they're locked or not locked everywhere, and he changes in that locking.
Those are the kinds of things that they can prison.
And that is the kind of thing that really, the Japanese also have looked for done.
So we can do that.
Those kinds of things with the Japanese did on the West Coast.
We can't do strain that Probably particularly well, although I would never think that during their pretty good what they do subduction zones up because I had to do with bodies of water, you know, like you have to actually have all these sort of GPS detectors, like, you know, you have your other you go sort of ease the abduction.
He actually have the entire Pacific Ocean.
Kind of like, How does it work.
What just seduction zone?
So let's go with the first order rule is that if you want to see, um with GPS, if you wantto see and motion and activity that occurs physical physical source that occurs over a scale that say 30 kilometers wide and 30 kilometers deep, you need spacing of 30 kilometers on your on your network, at least or smaller.
So So the that shallow you go after the denser.
The seller of the affected denser, dense with the network has to be want deeper stuff.
You can get away with longer wavelengths because it creates a bigger spatial signal on the surface.
If you push it from further down, you're gonna get more and you push for the time you get a bigger expression, wider expression on the surface of the earth.
That means you could get away with less.
And so, for example, the subduction zone ones under Vancouver Island They have a very nice network, I think itself and there they measure.
That's where they made a good deal of the uplift and the relative motion.
And then they have ah ah network that is a bit less desert back into British Columbia again?
Because the signal tails off, Sir, what you get?
Um, that, of course, there are no GPS incidents out in the ocean.
There are such a thing as ocean bottom GPS receivers, and it is possible to What you do is you dumb one on the bottom of nothing.
You put one on the bottom, the ocean, and then you have a little antenna that rose up to the service and that antenna, and that intended is what records the GPS, satellite locations, intelligence.
It really tells you where the antenna is.
But if you know how just and the GPS is when you know where you know where the Internet, how much moving the issue is their expensive, their present.
To deploy their to maintain and GPS data, you have to have a lot of measurement in order to banging noise down.
GPS is very noisy.
That's something they don't tell you when they feel right in your little handheld GPS. 00:58:06.008 --> 00