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The glaciers of Alaska, the Canadian Rocky Mountains, the foothills of California, the Atacama Desert and Andes of Chile, they may seem worlds apart. But they are all connected along a geologic front line, the
eastern Pacific Rim. They\'re characters in the ongoing tectonic story of our planet, a story of the relentless subterranean forces that have convulsed our cities, scarred the landscape, and overshadow our future.

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Travel with University of Toronto geologist, Professor Nick Eyles, on a geologic
journey as he explores the Pacific Rim of fire from Alaska to the Andes.

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[MUSIC PLAYING]

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Yakutat, southern Alaska, is one of the most remote places on Earth, and one of the most dangerous. A tectonic intersection
where plates collide, rocks are uplifted and folded into high mountains that reach 6,000 meters above sea level.

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It\'s amazing how big in class these...

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To geologists like Nick Eyles and earthquake specialist Peter Haeussler of the US Geologic Survey, it\'s an opportunity
to explore a tectonic show plate. It\'s a world where ice has the final word, and glaciers sculpt the landscape.

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The size and scale of the Alaskan glaciers is stunning, giant expanses of ice each the size of a large city, a
modern version of the last ice age. It\'s also a changing world. The impact of global warming is clearly evident.

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So the ice is thinning quite
quickly here, isn\'t it?

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Yeah, that\'s right. I guess I had that map that was showing that
the ice was at the mouth of the bay something like 800 years ago.

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The landscape here is operatic in scale. Giant mountains form a high wall that fronts the Pacific Ocean. These mountains are
some of the fastest growing on the planet, forced upwards by crustal impact between the Pacific and North American plates.

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It\'s amazing where you can look from the Pacific Ocean and, presumably, out there a little ways is the Pacific
Plate. And here\'s this Yakutat microplate. And then there\'s North America right there, so good collision.

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The collision is especially intense because the Pacific Plate carries a tectonic passenger, a large piece of crust the size of a small
European country. As it dives down beneath its North American tectonic neighbor, the Yakutat Block slams into the coast of Alaska.

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Rocks that, until recently, lay well below sea level have been folded and uplifted high above the
coast. It\'s a strange surreal world that constantly surprises, where even trees grow on ice.

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On the ground, Nick and Peter are met by guide Nick Cole. Weather conditions in the
aptly named Icy Bay can shift quickly. It\'s not a good place to be on your own.

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Yeah, I\'ve also wondered about these terraces
over there. See those flat surfaces?

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Right, whether they\'re
tectonic or glacial? Yeah.

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The obvious interpretation is that
they are strong uplift events.

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Yeah.

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But they could equally be raised as a result of glacial isostatic.
You know, when you get rid of the ice, as you [? were?] [? told.?]

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So what else would you
look for in the landscape?

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There is an amazing diversity of rock
scattered on this beach, isn\'t there?

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Sure are. Yeah, this is incredible.

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This area is the most tectonically active part of North America.
And we\'ve got all this glacial landscape we\'re looking at.

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This enormous erratic that\'s here.
It\'s really cool.

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And you can be quite specific about
where that\'s from too, can\'t you?

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Yeah, that\'s right. That probably came from at least 100
kilometers on the other side of the mountains here.

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So high uplift, formation of glaciers, the glaciers start cutting deeply
down into the mountains. And they start dragging all this debris out.

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Right, yeah. The glaciers really act like a conveyor belt, really effective at removing material
from the mountains, bringing it outward, and leaving bigger [? attics?] and stuff behind.

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Glacier ice roads carry rock back to the ocean, tearing down the mountains in the
process. Lines of rocky debris, called medial moraines, stretch for tens of kilometers.

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The ice itself is hundreds of meters thick and is pushed by gravity over a slurry of wet sediment and water. There are open crevasses
everywhere as the flow accelerates. Elsewhere, giant folds record compression as the ice slows towards the glacier\'s margins.

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Alaska is slowly growing. Large pieces of crust, carried by the Pacific Plate, collide with North America and
they\'re moved north along major faults, such as the Fairweather Fault and further south the San Andreas Fault.

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These blocks have been in transit for around 200 million years. And
their ultimate fate is to attach, to accrete, to western North America.

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Much of Alaska didn\'t even exist 200 million years ago, probably about the same for British Columbia. About half
of British Columbia didn\'t exist 200 million years ago. It\'s pieces that were somewhere else out in the oceans.

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So there\'s like little open pieces of crust, which have come from long way away, maybe thousands of
kilometers, and ended up colliding with western North America and being stuck on like a jigsaw puzzle.

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That\'s right.

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Turnagain Arm, near Anchorage, illustrates both the scale and the differing speeds of the accretion process.
The vistas that so impress may look fixed and immutable. But the rocks have all come from someplace else.

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Did notice as we drive along these rocks, they\'re highly deformed.
What do they tell us about the past tectonic activity along here?

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Yeah, they sure are. This is part of the accretionary complex that\'s in here. And basically, this larger package of rocks reflect
something like 200 million years of Earth history. So it\'s a really beautiful record of accretion along the southern Alaska margin.

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These rocks right here were probably related to the oldest phase of that accretion. And so a relatively
narrow belt of rocks, but the time span that\'s within it is probably on the order of 120 million years.

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And the next group that\'s kind of outward, the next chapter of Earth history that you see within this, actually reflects probably
only about 20 million years of history. And yet it\'s probably the most volume of the entire Chugach [INAUDIBLE] Mountains.

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This part of the American rim is also earthquake
country, a consequence of the Earth\'s crust on the move.

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The tidal flats in Girdwood, near Anchorage, contain a rich seismic history preserved as ghost forests and in layers of peat and mud below. The last
major quake was in 1964. And its impact on landscapes across southern Alaska provided the key to reading the record preserved in the sediments.

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Oh, wow. Look at these tree roots right here. Those are gorgeous. That is beautiful.
So that would have been the \'64 forest floor, beautiful interlocking roots.

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So you say approximately two meters of subsidence during
the earthquake. So these guys would have been up there.

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Way up there, yeah.

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Growing well above the high tide
area, well above salt water.

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Yep.

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And then they were dropped down and killed.

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Yeah. Yeah, so two meters would have put
them up like that level or something.

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And then the gray shelf on top is all the
marine sediment that flooded over that bank.

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That\'s come in since then, yep.
That\'s exactly right.

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Discoveries here and elsewhere have led to a new scientific discipline called paleoseismology, which calculates
the timing and frequency of past earthquakes. In this way, geologists can assess the risk to modern communities.

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So what are we looking at here, Peter?

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Well, you can see, with a little bit of work here, we\'ve been able to expose this really nice sequence. So up here are
these silts and muds that were deposited since the 1964 earthquake. So all of this has been deposited since then.

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And then this horizon right there, that\'s
March 27, 1964. That\'s 46 years ago.

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And then below that is the forest floor from before the \'64 earthquake. And then,
presumably, we\'ll go downward. And we have roughly 900 years of history below that.

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By studying a sequence like this, it helps you know what to look for in other places for older earthquakes. And so, for example, after seeing this kind of thing, one worker then went back down to Oregon and Washington and
found similar evidence for big earthquakes down there. And since then, there\'s been a strong case made for something like a magnitude nine earthquake in Oregon, Washington, and southern British Columbia in the year 1700.

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The great Alaskan earthquake of March 1964 is the largest ever recorded in North America, 9.2 on the Richter scale.
It had a devastating effect on the city of Anchorage. Coastal cliffs collapsed, carrying houses far out to sea.

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Before the earthquake, there was a big
bluff here, had houses on the top.

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So this whole area must be underlain
by debris from those large landslides.

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Yeah, that\'s right. Sometimes, if you\'re walking around out here, you can see either bricks or pieces of pipe, sometimes a piece of porcelain
that came from the houses that were on the bluff here. There were about 75 houses that were destroyed in that landslide that occurred right here.

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When the earthquake occurred, the epicenter was about 100 kilometers away from here. And the initial traveling of those seismic waves, you can think about a bit
like dropping a pebble in a pond in that the waves sort of travel outward from that. But all earthquakes generate waves that have different speeds to them.

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So the first waves would have hit the Anchorage area roughly 20 to 30 seconds after the earthquake started
in the middle of Prince William Sound. And that initial shaking would have sort of been this big jolt.

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But then a few seconds later, the big shaking would have occurred. And that would have
been so violent that it probably would have been hard to actually stand at that point.

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This is a city built on soft marine sediment. And in 1964, much of its downtown sank when the seemingly solid earth turned to quicksand. Downtown
Anchorage was badly hit. Multi-story buildings took the brunt of the damage. In a matter of minutes, thousands of people were made homeless.

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Before long, the seismic shaking actually subsided. But the effects of the earthquake weren\'t done in that the tectonic tsunami then hit the coast of
Alaska within roughly 20 to 30 minutes of the earthquake. That devastated both Seward as well as Kodiak and some of the villages down in that region.

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One of the saddest stories was at the village of Chenega. The water initially receded from the village. And a lot of people saw fish flopping
around in the tidal flats. They went down to get them. And then the waves came in and killed 33 people there, a third of the community.

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After the earthquake, the tsunamis
happened. And that was done.

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But down at the village of Portage then, within the next couple of days, these very high spring tides came in, inundated
that community, and basically made Portage a place where people could no longer live. It killed the community.

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Right here there was about two meters of subsidence that happened in 1964, which would have been almost instantaneous. And as a result of that, all of a
sudden, the buildings were within the tidal zone. And so after the earthquake, there were high tides that were coming all around this community here.

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So it\'s not just this plot either, is it? You\'ve mapped
it over a much larger area, that area of subsidence.

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Yeah, that\'s right. There was a huge area that was mapped out that
subsided. And this was kind of the axis of where the most subsidence was.

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The tides brought in the silt, which filled in the floor.
And now we feel like giants in a little house here.

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Large earthquakes and the rapid uplift of mountains are all expressions of
tectonic accretion as crust is added to Alaska. And the impact doesn\'t stop there.

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The collisional forces that were unleashed along the rim pushed far inland, deep into the interior of North America.
In Canada, the iconic Rocky Mountains were carved by glaciers into rocks buckled and pushed far to the east.

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Running south along the rim there is other striking evidence of tectonic forces at work. The
infamous San Andreas Fault is one of the most extensively studied fault lines on the planet.

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It\'s a seemingly endless gash in the landscape. The fault is part of the seismic grid that reaches
as far south as Mexico and which makes the region and its cities particularly vulnerable.

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At ground level, it\'s a different picture. The setting of the DeRose winery near Hollister, south of San Francisco, looks
idyllic and hardly precarious. But it sits astride the San Andreas Fault. As the fault moves, so does the winery above it.

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Alphonse DeRose and his father took over the business in the 1980s,
though the vineyard itself and some of its vines date back to the 1800s.

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On average, we have about five earthquakes a day.
But they\'re below a 3.0. So we don\'t feel them.

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Alphonse is philosophic about the geological
pressure cooker beneath his feet.

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So we\'re looking down right
at the San Andreas Fault.

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Yes, and you can get a good idea of the movement by looking at this crack here. We\'ve actually had to lay
cement here a couple of times over the last 10 or 15 years. So it\'s real, real evident of the movement.

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And actually, if you take a look at this wall right here, this wall used to be flush
with that post over there. So over the last 50 years, it\'s moved about 15 inches or so.

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So the buildings are actually being
torn in two. What else is happening?

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Actually, you can see some buckling
on both ends of the building.

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Have you ever had a major
earthquake while you\'ve been here?

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We did have one back in 1989. But the epicenter wasn\'t
here. So I don\'t even think we broke a wine glass here.

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Follow the San Andreas Fault north, and there\'s even more at stake. It travels right
through the heart of San Francisco. And that\'s only one of the city\'s geologic challenges.

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The rocks have been really
highly deformed, haven\'t they?

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Yeah, the process of abducting them up onto the
continent from the sea floor wasn\'t a pretty process.

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Mark Zoback is one of America\'s leading authorities on earthquakes
and an advisor on risk management to the United States government.

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There\'s a fault to the west of the San Andreas, the San Gregorio Fault. That\'s an active fault. The San Andreas is the big player. But as we go east to the Hayward Fault, there are many ideas and many models that suggest that,
over geologic time, the Hayward Fault is going to be the main actor accommodating the motion between the plates. And so it\'s a constantly evolving process, although it takes millions of years for that evolution to occur.

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The Bay Area may be cradled between the San Andreas Fault to the west and the Hayward Fault
to the east, but there are myriads of smaller faults and likely others that remain unknown.

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The city lies above a seismic subway system. The Cal Memorial Stadium at UC Berkeley is especially
at risk, the Hayward Fault running from goalpost to goalpost. Look closely, and the cracks appear.

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The football stadium at Berkeley has a dubious distinction of being built right on top of the Hayward Fault. And the fault pretty much runs along the center line at the stadium.
And as a result of slow creep along the fault, this half of the stadium has moved north relative to that half. And we can see evidence of that movement here in the wall.

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This is a deep crack. You can
see this wall has been offset.

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And on a larger plate tectonic setting, that is North America over here.
This is the Pacific Plate. And we are right on top of a plate boundary.

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The signs of damage can be found all the way around the stadium, such as these deep cracks here. And the building has now been so
severely deformed by fault movement that it requires a comprehensive retrofit involving the use of braces to keep these walls up.

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San Francisco is renowned for its setting, its imposing scale. The Paris of the West, it\'s famed for its street cars, its
hills, and the elegance of its architecture, which at the turn of the last century sought to rival Chicago and New York.

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The city is also known as the scene of one of America\'s worst disasters, which struck early on the morning of April
18, 1906. 28,000 buildings were destroyed. 3,000 people killed, half the population of the city left homeless.

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The earthquake actually nucleated just offshore, very close to Golden
Gate Park. That fault ruptured both to the north and to the south.

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The strong waves from the earthquake hit San Francisco almost immediately. It was so close to the epicenter of the event. The shaking was most intense around the
periphery of the bay where structures were built on soft sediments. The shaking was much less intense up on the hills where the houses were being built on bedrock.

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Down in the streets by the harbor, the earthquake\'s
effects are still evident a century later.

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When this area was violently shaken in 1906, this area collapsed. And you can see that on the street level behind me. The effects are dramatically
seen here in the buildings today where second story windows are almost at street level and entryways are now well below street level.

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Now the shaking itself, of course, is what knocks buildings down. But in the case of San Francisco, the damage was caused first by the shaking but then by the fires. As fires broke out, it
turns out that the water lines were badly damaged. And it was impossible to fight the fires. So in fact, it was the great San Francisco earthquake and fire that really destroyed the city.

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But that was a long while ago. How do San
Franciscans, like Raymond [INAUDIBLE], feel today?

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Living in an area that subsided during the earthquake, and in a house
that might collapse during the next one, that doesn\'t worry you?

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No. No, I could run outside.
I\'m cool with it.

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And you knew the history of
the area when you moved in?

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Oh, yeah. I\'m not really too afraid of it.

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Is the building still settling?

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Yeah, sometimes. But the one apartment I lived in out in North Beach, the whole building shook. And I was
actually watching The Day the Earth Stood Still. And the earthquake came. Yeah, it was really weird.

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Back in 1906, the university campus in the nearby community of Stanford was also badly damaged. Even
the geology building took a hit, the imposing spire of the Memorial Church crashing through the roof.

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The campus is now being steadily retrofitted in preparation for the next
earthquake, an event which Stanford Professor Mark Zoback believes is coming soon.

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There are about six dangerous faults, six capable faults of producing damaging earthquakes in what is considered really the next 30 years is the way we\'ve been looking at it. If you look at the cumulative probability that an earthquake on one of these six faults will cause severe shaking in the San Francisco
area, the cumulative probability is about 60% in the next 30 years, which means it\'s about twice as likely to occur as not to occur. So from the perspective of the people who live here, from the perspective of the people who have to respond to the earthquakes, we have to think of it as just about a sure thing.

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Leaving California, Nick heads south to one of the most earthquake prone regions on the planet, Chile, where thousands of kilometers of coastline are
at risk. Back in 1960, it was the scene of the largest earthquake ever recorded, which triggered a devastating tsunami felt right across the Pacific.

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Northern Chile is one of the driest places on Earth, the Atacama Desert where rainfall can be as low as one millimeter a year. The low lying coast is flanked by imposing volcanic cliffs, which increase the potential
impact of tsunamis, which have been known to be as high as 25 meters. Cities like Antofagasta perch precariously on the narrow strip of land beneath the 1,000 meter high Cordilleras, squeezed between ocean and desert.

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Antofagasta is home to a quarter of a million people. Its prosperity is dependent on its rocks. Minerals
from the giant mines of the Atacama are carried to the coast by rail and shipped around the world.

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Earthquakes are common here. The last, in 1995,
shifted the city 80 centimeters to the west.

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Deep under the coastal strip, the floor of the Pacific Ocean and its underlying crust, the Nazca Plate, is being forced under South America. A never-ending
cycle of stick and slip between the two triggers sequences of large damaging earthquakes. Far inland, recycled ocean crust feeds Andean volcanoes.

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The descending Nazca Plate acts as a giant wedge, each earthquake pushing up the Chilean coast by many meters, abruptly raising it from the ocean.
At Portada, raised marine rocks illustrate the ongoing cycle of earthquakes and uplift, a process that was first interpreted by Charles Darwin.

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Well, these cliffs are really important in what they tell us about the origin of the Andes but also in the history of science. Because in 1834 to 1835,
a very young Charles Darwin sailed along this part of the coastline in the Beagle. He came ashore and noticed these shells, now high above sea level.

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And in 1835, he witnessed a major earthquake, which destroyed the city of Concepcion. And he noticed
that the coastline was uplifted. Shells that were living in the sea were now raised above sea level.

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And he interpreted these rocks here as a result of repeated earthquakes and jacking up of the coastline. It was a major insight into how mountains are
formed and also, for him, into the origin of a dynamic evolving planet, which was, of course, a springboard for his later ideas on evolving species.

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North of Antofagasta, the ruins of the once flourishing port of Cobija are a testament to the destructive force of tsunamis and the continuing vulnerability of coastal settlements. The port was hit by an earthquake in 1868 and then,
less than a decade later, was engulfed by a tsunami when 10 meter high waves crashed through its streets. The community, which had also been hit with a yellow fever epidemic, decided that the place was cursed and best abandoned.

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Moving inland towards the Andes, Nick\'s journey takes him across the Atacama Desert and its Mars-like topography.
The landscape is seemingly sterile, devoid of vegetation. But geologically, it\'s anything but empty.

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The Santa Elena Mine was once the world\'s primary source for nitrates used in the production of both fertilizer and gunpowder and played a key role in fueling the
rival armies facing each other in the trenches of the first World War. The scale of production was immense, so to are the giant heaps of tailings that remain.

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The Atacama Desert still has many mineral resources. But today, it\'s
copper that\'s king and is the backbone of the nation\'s economy.

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The Chuquicamata Mine is the world\'s largest open pit copper mine. Its scale is
simply immense, 4.9 kilometers long, 3 kilometers wide, and a kilometer deep.

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The copper here is found in the giant roots of long dead volcanoes where ancient Pacific crust melted at depth, and magma forced its way to the surface. Deep
waters under great pressure and temperatures gleaned the metal from the hot rock, concentrating it into rich veins of green and turquoise colored minerals.

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Soon to be expanded still further, the pit and its enormous piles of waste rock looms above the former
company town. It\'s deserted now. But the buildings have been kept, a sideshow for the curious tourist.

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About 100 kilometers inland, the landscape changes yet again. Far in the distance, the Andean Mountains dominate the skyline. Massive volcanoes rising 5,000
meters above sea level warn of other forces at play. The impact of all that explosive power, along with the influences of time and climate, is everywhere.

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The landscape appears pummeled, rocks bent and broken, shaped into strange and contorted forms by tectonic collision and erosion. It\'s no
accident that Valley de la Luna, or Valley of the Moon, is named after our lunar cousin and is used as a training ground for astronauts.

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But as so often on Nick\'s journey, there are surprising twists to the geologic plot. The
strangeness of this alien landscape is made all the more dramatic by the presence of salt.

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The salt beds are remnants of ancient lakes long since evaporated. The
deposits add yet another texture to a landscape sculpted by wind.

00:35:30.000 --> 00:35:38.000
The Valley de la Luna is a junction where vanished lakes meet the longest and highest volcanic
mountain chain anywhere on the planet. To a geologist like Nick, it\'s a euphoric experience.

00:35:44.000 --> 00:35:50.999
These are some of the most wonderful, beautiful landscapes
I\'ve seen anywhere on planet Earth. They\'re just fantastic.

00:35:51.000 --> 00:35:59.000
And equally dramatic is the plate tectonic story that these rocks tell us. Because about 100 kilometers below us is the descending floor of the Pacific Ocean, the so-called Nazca Plate. That\'s melting
at those depths under very high pressure and temperature. And the molten rock is rising back to the surface as these giant volcanoes that we see in the distance, making up the main range of the Andes.

00:36:17.000 --> 00:36:25.000
South America is moving this way. The descending plate is moving against it in the opposite direction. And these rocks here are being tortured. And
they\'re being folded into these beautiful shapes that we see today. So they\'re literally in a vice created by these opposing plates moving together.

00:36:50.000 --> 00:36:55.999
It\'s the driest desert on the planet.
And it\'s also the oldest.

00:36:56.000 --> 00:37:04.000
The scale and thickness of the salt beds tell another more ancient story of climatic cycles causing lakes to repeatedly fill and then dry out.
Salt has been mined in this area for thousands of years. The remains and relics of abandoned salt mines are a familiar character in the landscape.

00:37:23.000 --> 00:37:31.000
That process is still at work. Salt continues to accumulate in enormous
evaporating basins, called solars, that cover hundreds of square kilometers.

00:37:42.000 --> 00:37:50.000
This is a barren wasteland today. But 10,000 years ago, it was completely different. And we would\'ve actually been under water, under a fresh water lake. And the
climate here would have been much more humid. There would\'ve been trees growing around there. There would have been large animals, people hunting those animals.

00:37:58.000 --> 00:38:06.000
And then it changed. About 8,000 years ago, it got to the present condition where it\'s
hyper arid, desert. And people began to live in oases. You can see one behind me.

00:38:09.000 --> 00:38:17.000
People lived in close proximity with animals. And that\'s the start of domestication.
So there was a profound effect of climate change on society in these Andean countries.

00:38:26.000 --> 00:38:34.000
Just a few kilometers from the Valley de la Luna and its adjoining solars, there are other indicators of a weathered more fertile past. These deep canyons were cut by ancient rivers. Ash beds within the steep canyon walls
document the 20 million year history of the growth of the Andes. Each chapter is embedded in the rock and records the extraordinary violence of past eruptions in which enormous volumes of ash were hurled into the atmosphere.

00:39:09.000 --> 00:39:17.000
The canyons are also a vital source of water and shade. The springs and adjoining oases have, for millennia, provided a lifeline for the Atacameno
people, who have had to learn how to live with periods of rapid climate change. They\'ve also had to live with the continuing threat of volcanoes.

00:39:42.000 --> 00:39:50.000
Local archaeology suggests that the Atacamenos have been settled in the area for 11,000 years. The
original community of Talabre lay directly below Lascar Volcano, the most active in the Chilean Andes.

00:40:07.000 --> 00:40:15.000
Sotero Armella, a community leader, grew up on the slopes of Lascar and witnessed many eruptions before he and other villagers decided to move to higher ground to avoid the ever
increasing threat posed by lava and ash flows. The narrowness of their escape is captured in stone by the sheer size of the now cooled lava flow that sits menacingly above the village.

00:40:41.000 --> 00:40:49.000
Lascar Volcano may be the most dangerous in Chile. But it\'s simply one of many clustered in a molten
assembly that forms the Andes. Each volcano is fed by magma rising from Pacific crust melting deep below.

00:41:00.000 --> 00:41:08.000
When cooled, magma gels into rocks called andesite and rhyolite, which act like a champagne cork,
preventing the release of gases until the buildup of pressure leads to a catastrophic eruption.

00:41:22.000 --> 00:41:30.000
As a geologist, I\'m just blown away by this view. It\'s so spectacular. We can see the lava flow that\'s come down. We can see its
cooled outer edges and then the gray colored ash. And you can see fingers of the ash flows that have traveled down the lava.

00:41:38.000 --> 00:41:42.999
It\'s preserved because it\'s dry here. Everywhere
else in the world that would get eroded.

00:41:43.000 --> 00:41:48.999
You were working up here during the 1993
eruption. What was it like to be up here?

00:41:49.000 --> 00:41:55.999
[SPEAKING SPANISH]

00:41:56.000 --> 00:42:04.000
Back in April 1993, as luck would have it, I had gone up the far side of the mountain to get my sheep and llamas when I
saw a mushroom-shaped cloud. I put up my hands to shield myself because, suddenly, lots of tiny stones begin to fall.

00:42:14.000 --> 00:42:22.000
At first they were very light, like sponges. But then they started getting
heavier and heavier. And if one of those would hit you, then forget it.

00:42:28.000 --> 00:42:36.000
Given such extremes of temperature and seismic threat, local communities are especially respectful of the
earth and of the power of volcanoes. And all across the Andes, there are ceremonies that ritualize that awe.

00:42:47.000 --> 00:42:52.999
[SPEAKING SPANISH]

00:42:53.000 --> 00:43:01.000
The most important thing you have to have for the offering is cocoa.
We also bring corn, flamingo feathers, incense, quinoa, all that.

00:43:04.000 --> 00:43:07.999
[SPEAKING SPANISH]

00:43:08.000 --> 00:43:13.999
And we make these little llama figurines and
offer those up too. That\'s what we bring.

00:43:14.000 --> 00:43:22.000
As far as alcohol goes, it has got to be 90% proof. And then there
is other drinks, like beer and wine, food, that kind of thing.

00:43:37.000 --> 00:43:45.000
Further south in Patagonia, the climate may be very different and the vegetation more burden, but the deep subterranean forces are the same. The coastal
ferries still stop at Chaiten. It\'s a transit point for local people heading south. The few adventurous tourists who stop by don\'t stay for long.

00:44:13.000 --> 00:44:21.000
In May 2008, the entire town of Chaiten was evacuated shortly
before being engulfed in a wave of wet volcanic ash.

00:44:28.000 --> 00:44:29.000
Hola.

00:44:29.001 --> 00:44:30.999
Only a few people returned.

00:44:31.000 --> 00:44:31.000
Hi, how\'s it going?

00:44:31.001 --> 00:44:32.999
Good. Good to see you.

00:44:33.000 --> 00:44:38.999
Among them, Nicolas La Penna, who runs a
local travel agency and the post office.

00:44:39.000 --> 00:44:41.999
The volcano\'s over there. And
[INAUDIBLE] a bit later.

00:44:42.000 --> 00:44:43.999
So you\'re still living
here after the mud flows?

00:44:44.000 --> 00:44:52.000
Of course.

00:44:54.000 --> 00:45:02.000
The scattered possessions speak of the urgency of the threat,
telling of the sudden death of a once vibrant community.

00:45:11.000 --> 00:45:19.000
This whole eruption was very quick. Basically, within two and a half days, the volcano blew from the first signs of a tremor before it blew at night on
Thursday night, basically. And then Friday morning, when we woke up, there was a 15 kilometer plume over our town, which went to 30 kilometers, basically.

00:45:32.000 --> 00:45:33.999
What was the reaction of the townsfolk?

00:45:34.000 --> 00:45:42.000
Complete surprise because many people here had no idea there was a volcano right next to the town. [INAUDIBLE]
amazing forest, it\'s so dense. It was quite low. It\'s not a high volcano, very well hidden. It blends in very well.

00:45:48.000 --> 00:45:56.000
Luckily, it was very good weather that day. And the major ferries were in the area. So the government basically arranged everything. And we had the largest
civilian evacuation by ocean ever in the history of our country. Something like 3,500 people in 24 hours left town by the ocean. And it was all full of Navy boats.

00:46:09.000 --> 00:46:17.000
And since people here have we\'ll say brothers and family in Chiloe, on the island out there, even they came over, their family
members who were fishermen, and brought them all back, like family, personally to safety. A very, very emotional moment actually.

00:46:33.000 --> 00:46:40.999
Most volcanic eruptions are hot, noisy, and fiery events.
But volcanoes can also be stone cold silent killers.

00:46:41.000 --> 00:46:49.000
What happens is, during a major eruption, huge volumes of fine ash mantle the slopes around the volcano. Weeks, months pass. All that ash,
wetted by intense rain, moves down valley as a lahar, a mud flow. And, as it happened in Chaiten, buries the town under meters of ash.

00:47:08.000 --> 00:47:16.000
Further up the valley, dead trees tell of hot
gases expelled like a shock wave down the slope.

00:47:26.000 --> 00:47:34.000
There\'s a real sense of danger here, isn\'t there? We\'re looking up to the volcano. I
suppose every time that collapses, all the red hot debris is just swept through here.

00:47:35.000 --> 00:47:43.000
Oh, yeah. It\'s a very dangerous place because
Chaiten town is 10 or 12 kilometers from the site.

00:47:46.000 --> 00:47:54.000
Dr. Luis Lara is Chile\'s foremost volcano watcher and has been monitoring the volcano since it\'s reawakening in 2008. Before
that, radiocarbon dating confirms that Chaiten hadn\'t erupted in more than 9,000 years and was presumed to be dormant.

00:48:08.000 --> 00:48:14.999
So this is the side slope for the volcano
collapsing, huge boulders and a lot of ash debris.

00:48:15.000 --> 00:48:22.999
Yes.

00:48:23.000 --> 00:48:31.000
The volcano is still very active, a smoking molten mass where the damage from pyroclastic flows and explosions
is shocking. The dome of the new volcano is forcing its way up through the collapsed crater of the old.

00:48:51.000 --> 00:48:59.000
The growth of the gigantic dome has been extraordinarily
fast. And this is where the danger lies.

00:49:05.000 --> 00:49:12.999
The entire dome here was [INAUDIBLE] during
the last eruption, during the last year.

00:49:13.000 --> 00:49:16.999
So this volcano has yet to
have its first birthday?

00:49:17.000 --> 00:49:18.000
Yeah.

00:49:18.001 --> 00:49:23.999
That\'s amazing.

00:49:24.000 --> 00:49:32.000
There are close to 100 active volcanoes in Chile, of which 20 are thought to be high risk. And it\'s
Dr. Lara\'s unenviable responsibility to monitor their health. He worries what the future may bring.

00:49:42.000 --> 00:49:50.000
What\'s very impressive too is the amount of ash that\'s trapped in this old crater. If these
walls ever get broken, the natural discharge is down slope. Be a huge disaster, wouldn\'t there?

00:49:55.000 --> 00:50:00.999
Yeah, that\'s the big problem
with this kind of volcano.

00:50:01.000 --> 00:50:09.000
After the eruption, the lahar, or mud flow, blocked the course of Chaiten\'s Blanco River, causing it to flood the downtown streets
with water and silt. Despite all of these obstacles, no power, a compromised water system, some people are determined to stay.

00:50:25.000 --> 00:50:33.000
The government maintains that, given the threat of new eruptions,
the town is best abandoned. But Nicolas thinks otherwise.

00:50:35.000 --> 00:50:40.999
What do you think of government suggestions that the town
effectively should be killed and everybody moved somewhere else?

00:50:41.000 --> 00:50:45.999
Well, everyone has different opinions. And every
opinion is worth listening to because there\'s reasons.

00:50:46.000 --> 00:50:54.000
If it was just a flood and say our town was destroyed by a flood, in a week we come back and fix it. But just like you were
saying, it\'s a volcano, a very maybe atypical volcano here in Chile. And we don\'t know its characteristics, what it can do.

00:51:03.000 --> 00:51:11.000
So there\'s caution here too. So there\'s this fine line, I think, here. But
what would you do, Nick, if you were in this situation? Would you just...

00:51:12.000 --> 00:51:14.999
As a geologist? It\'s a
very dangerous situation.

00:51:15.000 --> 00:51:16.000
Yes, yes.

00:51:16.001 --> 00:51:17.999
And it can only get worse.

00:51:18.000 --> 00:51:18.000
Yes.

00:51:18.001 --> 00:51:22.999
Lahar\'s already been through the town. And
what would happen if a pyroclastic flow...

00:51:23.000 --> 00:51:24.000
Sure, it\'s dangerous.

00:51:24.001 --> 00:51:26.999
If the dome collapsed, what do
you think would happen here?

00:51:27.000 --> 00:51:29.999
I don\'t think it would be a good scene
at all. It wouldn\'t be good at all.

00:51:30.000 --> 00:51:31.000
People would be killed.

00:51:31.001 --> 00:51:39.001
Yes, it\'s dangerous.

00:51:45.000 --> 00:51:53.000
But to a geologist like Nick Eyles, what\'s happening at Chaiten is a tiny part of the big picture, the inevitable geologic journey of the Earth. The
volcano may look like a malevolent destructive slag heap. But it\'s part of a tectonic process that is building new land, reconfiguring our planet.

00:52:08.000 --> 00:52:16.000
It\'s been a dangerous journey in many respects. Chaiten Volcano, this is what we have here, is just one of thousands that dot the extremities of the Pacific
Rim. And there\'s about a billion people that live on the Rim in constant fear of volcanic eruptions, major earthquakes, and, of course, tsunamis, tidal waves.

00:52:26.000 --> 00:52:34.000
But on a bigger geological picture, we\'re looking at the transformation of the Earth\'s surface. Because, slowly over time, the
floor of the Pacific Ocean is being destroyed. It\'s being subducted by being pushed down below the surrounding land masses.

00:52:42.000 --> 00:52:50.000
Those land mass are slowly moving inwards. And in about 120 million
years time, instead of a large ocean, there will be a supercontinent.

00:53:03.000 --> 00:53:11.000
This process has been at work since the birth of the planet billions of years in the past, the continents enlarging at the
expense of the oceans. Land and water locked in an eternal collision, a grand battle that defines the course of Earth history.

00:53:36.000 --> 00:53:41.000
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