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Scientists predicted latest quake -

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Scientists predicted latest quake

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TONY JONES: It's now well known that the devastating Boxing Day tsunami was triggered by an immense
undersea earthquake. The waves were generated by the huge volumes of water displaced by the sudden
movement of two great undersea plates in the Earth's crust. The edge of the Indian plate slipped
under the Burma plate. Naturally enough, that terrible fracturing of the Earth was of tremendous
interest to geo-physicists. They're the only people capable of answering the questions - could it
happen again and when? The first major study came, rather surprisingly, from a team of
environmental scientists at the University of Ulster. They were led by Professor John McCloskey.
And they found that the rupture of the Boxing Day, the quake created two hotspots, likely to
generate new quakes. McCloskey's team released its findings only two weeks ago, accurately
predicting the location of the latest earthquake and its magnitude. The only detail the study
missed was the timing. Professor McCloskey joins us now from Derry.

I spoke to John McCloskey a short time ago in Ulster. John McCloskey, thanks for joining us.

PROFESSOR JOHN McCLOSKEY: Thanks.

TONY JONES: Can you begin by explaining for us how the undersea earthquake on Boxing Day created,
effectively, new danger zones and what that means for us now?

PROF JOHN McCLOSKEY: Our research looks at the communication between earthquakes - when an
earthquake happens, basically a plane within the Earth's crust has a displacement on it and that
displacement distorts the whole region of the crust. Let me try and explain. If we had a block of
rubber on the table in front of me here and I pushed my thumb into the side of that block it
wouldn't only distort the surface that I was touching, but it would actually - the distortion would
invade the entire block. Everywhere within the block could feel the forces generated by my thumb
pushing at one side. You can imagine that the December 26 earthquake actually distorted a surface
within the Earth, which was 1,200km long by about 200km wide. This is a phenomenal area. It's twice
the surface area of Ireland, for example. I'm not sure how much that means to you, but it means a
lot to us here.

TONY JONES: So that distortion that happened with a massive rupture on Boxing Day has created
specific new areas which will lead to quakes inevitably. Is that what you are saying?

PROF JOHN McCLOSKEY: What we've done then is that we have been able to calculate the value, or the
amount of force generated everywhere within the crust in the Indonesian region. The next part of
our technique is we look for structures, other earthquake faults in the area which have produced
large earthquakes in the past, and we then calculate how much force has been accumulated or indeed
released on the faults in that area. So this can sometimes increase the stresses or forces on other
faults. Sometimes it releases them. We identified two areas which had significantly increased the
amount of force or stress on them and we then looked for other work which had been done on the
history of earthquakes on these two structures. Of particular use here was the work of the group of
Professor Kerry Sieh of the Californian Institute of Technology, who has done some very detailed
and painstaking work on the history of earthquakes on the Sunda trench subduction zone. This work
showed that area had historically generated earthquakes of a magnitude 8 to 8.5. And therefore, we
identified this as the type of earthquake we were concerned about in the Sunda trench case.

TONY JONES: Can I interrupt there, that area - just to identify where the Sunda trench is, that's
off the northern tip Sumatra, are you saying that this is where you predicted there would be an
earthquake. Is that where it actually happened over the past few days?

PROF JOHN McCLOSKEY: To the south of the rupture of the December 26 earthquake, we calculated that
between 50km and 100km of the crust there had been significantly stressed or the stresses had
increased there. It turns out that the earthquake of Easter Monday nucleated within that relatively
small area of 50km to 100km, which we had pointed out as being significantly stressed. The final
magnitude appears to have settled at 8.7. And that makes it pretty much the type of earthquake that
Kerry Seih was concerned about and we identified as the likely one. So the earthquake here has -
two of the very important characteristics were described in our work on the 17th of March.

TONY JONES: Has the main danger now passed? Has the stress in the Earth's plate, in the Earth's
crust, that you were identifying there, these new stresses, have they now played themselves out
effectively or are we still likely, in your opinion, to see more big quakes in that area?

PROF JOHN McCLOSKEY: I am... Our work suggested there were two earthquake faults in this area which
had experienced significant increases of stress due to the Boxing Day earthquake. Clearly one of
these earthquakes has now happened. The other one has not happened and the stresses there are still
high and they are associated with the same increased risk, and there has been no change in the
situation there. The fault of concern here is that the Sumatra fault at it runs - it more or less
bisects the island of Sumatra along its entire length - and the area that we are concerned, or were
concerned about in the paper published in March, and we continue to be concerned, is the northern,
about 300km of that, which has experienced very significant increases of stress. That, to give us
some idea of what we are concerned about here, in the past this fault has generated earthquakes on
the order of magnitude 7 to 7.5. And while this is very, very much smaller than the 9.3 earthquake
of December, or Easter Monday's 8.7 earthquake, a land-based earthquake - this is a
California-style earthquake, mid-7s and can be very devastating to buildings and people. So this is
a live issue. We are not being alarmist. We are not saying there will be another earthquake. We are
not in the business of earthquake prediction. However, this is - a reporter referred to it this
morning as a hot spot. I think that's a good description. It's an area of increased risk or
increased earthquake probability.

TONY JONES: And this hot spot you're talking about runs directly under the already-devastated city
of Banda Aceh?

PROF JOHN McCLOSKEY: Unfortunately that is the case. The highest stress we have measured is on the
northern part of that fault, which is near the city of Banda Aceh. So the risk in that area has
increased. I should stress again - we are not predicting an earthquake. We have no time variables
within the equations we're using in this case, so we don't have any control on time. I know that
it's very easy, given the fact that we were able to describe the Easter Monday earthquake so
accurately and the paper was only published two weeks before that earthquake, people are - it's
understandable that people will say this was an earthquake prediction. We hold very strongly that
it was not. We have identified an area of increased probability and in this case that increased
probability was translated into an earthquake within that period of time. We don't have any control
on time at all.

TONY JONES: No, that's understood. But what precautions would you recommend now that the
governments and aid agencies, those governments who are already spending huge amounts of money in
Aceh. What precautions should they take in that city, which may still be in serious danger?

PROF JOHN McCLOSKEY: There are some very obvious things. The first precaution I would take is to
make sure that the appropriate authorities within the Indonesian government take the proper advice,
not from an earthquake scientist like me, but from earthquake engineers who understand the
relationship between building control and building design and the vulnerability of buildings to
serious damage and, therefore, loss of life during the type of earthquake that we are concerned
about here. So there are many - we know, for example, that the island of Nias, which suffered such
devastation on Monday, I've heard reports that some of the buildings, which were damaged most
dramatically, were modern 2-storey concrete buildings, which have been built, with apparently
little reference to the Indonesian building codes. These are the type of developments that cause
major damage and major loss of life when an earthquake hits a built-up area. That's the most
important thing. Banda Aceh is being re-built at the minute. It's very important that - earthquakes
of magnitude 7.7 kill very few people in California. This is about building control, it is about
strong and earthquake-proof buildings. I also understand that the traditional Indonesian buildings
have survived very well. Even very close to the epicentre of Monday's earthquake. These are strong
lessons. The earthquake risk is high in this region. Building control, appropriate building for
this type of risk is vital at this stage.

TONY JONES: Can I interrupt you there because you did issue effectively with your previous study
another warning and that was that there could be more tsunamis as a result of the earthquake
potential that you had spotted. Do you believe that danger has now passed?

PROF JOHN McCLOSKEY: Certainly and very thankfully the earthquake of Easter Monday, which was big
enough to trigger a tsunami and earthquakes of magnitude 8 or 8.5 on the Sunda trench have
triggered tsunamis in the past and some of these tsunamis in 1833 and 1861 have been fatal. In this
case, thankfully, the tsunami I understand was very small and didn't cause any fatalities at all.
We are confident now that that particular segment of the fault has had its earthquake and the
chances of another earthquake occurring near there which could generate a tsunami is very, very
remote. So that particular segment we believe does not pose any threat now. However, the subduction
zone stretches for another 3,000km around the south of Sumatra towards Java. I am not expert on the
history of earthquakes in that region, and I think that's a very important matter that we do not
now think that because we've had two large earthquakes that there not be any more. One geological
certainty is there will be large earthquakes in this region. There have been large earthquakes for
all of the near geological past, there will be for the near geological future. The fact that we
have got away without a tsunami on Easter Monday earthquake does not mean there is any less
requirement for this tsunami warning system. There are dense populations living in areas which are
threatened by tsunamis from other earthquakes. Not the ones that our paper referred, to the Banda
Aceh earthquake if it happens will not create a tsunami, it's on land. However, there is a long
subduction zone. Earthquakes on any part of that can generate tsunamis. It's a live issue.

TONY JONES: Do you think it's acceptable that nearly three months after 270,000 people were killed
in the Boxing Day tsunami that there still isn't an Indian Ocean detection system for tsunamis?

PROF JOHN McCLOSKEY: I'm not particularly expert on this. I understand that work is in progress in
installing this. I'm certain that that is not a month's work. I'm not sure how long it takes, but I
believe that work is under way. I'm also heartened by the fact that it seems that while there
wasn't a tsunami on Monday, people behaved correctly in assuming that there would be, given the
size of this earthquake. False alarms are an important part of an earthquake preparedness program.
And people moving away from the sea on to high ground is exactly the type of behaviour which saves
lives and would have saved lives had that earthquake happened. So a tsunami warning system is not
just the high-tech solution which involves seismometers and floats which detect the travelling of
the tsunami across the sea. Very important parts of the system are earthquake preparedness training
for people so that they know what to do, they know what actions are most likely to lead them to
safety given a certain set of circumstances. Portland Oregon, for example, I visited recently. The
streets there are marked with colour codes to tell people how to get to high ground in the case of
a tsunami. This is low-tech, it's very effective, it builds public confidence and saves lives when
a tsunami wave is generated. You don't need a detection system to tell you that the ground is
shaking and you're on low ground. You need to move immediately. And that saves lives. And the
absence of the high-tech solutions, which I believe the high-tech systems are on their way. The
sooner the better, really.

TONY JONES: Professor John McCloskey, thank you for taking the time to talk to us tonight.

PROF JOHN McCLOSKEY: Thank you very much.