00:00This was an earthquake of magnitude 6.8,
00:04which is pretty big for Morocco.
00:07There's been nothing bigger than 6.0
00:10within 500 km of this since at least 1900.
00:14So this is, locally speaking, this is very big.
00:18Geologically speaking,
00:19it's not a surprise to have an earthquake like this.
00:21It's just that they're infrequent.
00:22Africa and Europe are colliding.
00:25Most of the action is further north,
00:27close to the Mediterranean.
00:30But the high Atlas Mountains are uplifted
00:33because of this collision between Africa and Europe.
00:35It's still continuing.
00:36So there are some earth movements beneath those mountains.
00:39And that's just what happened last night.
00:42And it will continue to happen.
00:44But these events on this scale are infrequent.
00:48And they're maybe once a century or even less frequent.
00:53It's done a lot of damage to buildings,
00:55particularly because it was in a mountainous region
00:58and it was a shallow earthquake.
01:01The initial rupture happened at a depth of a little bit less than 20 km.
01:05Had it been at 40 or 80 km,
01:08the shaking at the surface would have been much less.
01:10But it was shallow.
01:12Hence the amount of damage.
01:13I dare say the death toll will continue to rise as well.
01:18And I think many of the buildings in the area are quite old
01:21and certainly haven't been constructed to modern seismic resilience standards.
01:27If you build cheaply, buildings fall down more easily.
01:31They'll have to think very seriously.
01:33Now, they know that earthquakes of this size can occur in the region.
01:36Is it worth investing in earthquake-resilient buildings?
01:40But there may not be a quake this big in the same area for another century.
01:44So it's a very difficult decision to have to make.
01:47There will be aftershocks.
01:48There was a magnitude 4 point something aftershock about an hour after the initial earthquake.
01:53All the other aftershocks so far have been smaller.
01:56They will be worrying for people who are close enough by to feel them.
02:00But they will tend to be weaker.
02:02Normally they would not do much damage,
02:05except you've got buildings already structurally unsound because of the original earthquake.
02:09So there could be some more building collapse.
02:13And certainly rescuers are putting their lives at risk,
02:16crawling into rubble if there's an aftershock.
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