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[ Silence ]
>> And I was installing GPS measurements,
and trying to convince local authorities
that a earthquake hazard should be higher up on their list.
[ Silence ]
>> They were able to provide a likely scenario in that
that scenario actually did happen,
means that probably more attention should be paid
to scientists when they talk to authorities about hazards.
[ Silence ]
>> Are able to measure the position of benchmarks
that we install in blocks, with a precision of a millimeter.
We repeat those measurements over time.
So if those benchmarks move because there is deformation
in the Earth's crust in preparation
for an earthquake, then we can see that.
[ Silence ]
If you want to know the probability of an earthquake
on a given fault, it's very important
to know how fast a strain, elastic energy if you want,
is building up on that fault
to be released in future earthquake.
And that's where we are measuring essentially
with this technique.
[ Silence ]
This technique has been out there for about 15 years
at the level of precision that we have today.
The difference now is that we're able
to analyze much more data much more quickly
than we were before.
So we'll also be re-measuring the benchmark
that we have installed in the past on that fault,
and be able to look at the difference before
versus after the earthquake, and learn about the mechanics
of this particular event.
After an earthquake it takes months, years perhaps,
for the whole area of the Earth's crust around the fault
within say, 100 kilometers
around the fault, to fully recover.
And this recovery process is very important
because it's telling us a lot
about the mechanical properties of the Earth's crust.
So we have to jump at every opportunity we have to do that.
We can only do that when there is an earthquake.
It's kind of a laboratory.
It's a natural laboratory.
So when the earthquake happened, we run out there to be able
to measure those mechanical properties;
something you cannot do there easily in the lab.