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>> Earth, a four-and-a-half-

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billion-year-old planet, still

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evolving. As continents shift

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and clash, volcanoes erupt and

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glaciers grow and recede, the

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earth's crust is carved in

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numerous and fascinating ways,

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leaving a trail of geological

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mysteries behind.

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In this episode, the 450-

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million-year-old geological

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history of New York City is

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explored. A metropolis

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pockmarked with strange rocks,

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haunted by footprints of

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ancient giant reptiles, and

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lined with a vast curtain of

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solidified lava. Scientists

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investigate the evidence for

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fiery volcanoes, massive

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floods and ice sheets four

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times as high as the Empire

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State building. The clues to

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understanding New York City's

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geological past provides a

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window into the formation of

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the earth itself.

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S01x05 New York
Original Air Date on March 10, 2009

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== sync, corrected by elderman ==
@elder_man

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The investigation into New

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York City's geological history

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begins here, with Manhattan's

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rocky outcrops. These rocks

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are clues to how the land was

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made and how its geology

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helped it become a dense,

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thriving, pulsating city.

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They're scattered all over

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Manhattan, poking through the

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surface of parks and through

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the concrete between the

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buildings. Some, squashed

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between two apartment blocks,

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are the size of a whale.

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They are the extraordinary

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survivors of ancient times.

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Most importantly, they are the

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surface tips of the bedrock in

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which Manhattan's buildings

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are anchored. Gigantic

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skyscrapers stand in two

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clusters, in downtown and

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midtown. In the section

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between, the buildings are

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lower. The clues to the shape

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of Manhattan's familiar

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skyline are the rocks beneath

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the surface.

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A leading expert

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on the rocks in New York is

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geologist Charles Merguerian.

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>> The entire history of the

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development of the earth's

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crust is emblazoned in the

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rocks beneath us. The rocks

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here in New York City harbor

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an ancestry that dates back

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over a billion years of time.

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>> Merguerian is searching for

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evidence to show how the

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city's bedrock was made.

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At Inwood Hill Park in Upper

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Manhattan, he's found an

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extremely hard piece of the

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bedrock known as Manhattan

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schist. To the untrained eye,

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it's just a piece of rock, but

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to Merguerian, this is his

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first clue.

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>> The rocks that we're

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looking at right here are

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rocks of the Manhattan schist

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formation and the--these rocks

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are very severely deformed,

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and the structures here in

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this rock is a structure that

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comes up like this, bends

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around and comes back down on

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itself as such, and in

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three-dimensional view, it's a

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structure that looks something

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like this. A very, very tight

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fold with a plunge towards the

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south here. These are rocks

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that were very, very strongly

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deformed over protracted

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periods of time. And it's the

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same bedrock that occurs over

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much of New York City.

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>> This tight fold in the rock

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suggests New York's

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bedrock was formed under great

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pressure. To confirm this

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hunch, Merguerian takes a

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sample to the lab for detailed

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analysis. Radiometric dating

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proves this rock is about 450

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million years old. But the

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rock has even greater secrets

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to tell.

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It contains a kaleidoscope of

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minerals, which opens a window

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into the ancient world.

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>> To me, minerals are like

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the instrument cluster in your

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car, they tell you everything

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about how your car is running.

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>> Merguerian uses a

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microscope with polarized

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light to view the minerals.

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>> The examination tells us

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the former depth regime,

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how deep the rocks were, they

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tell you the age of the rocks,

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they tell you everything you

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want to know about the

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development of the earth's

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crust.

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>> What's striking about these

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samples is that the minerals

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inside are elongated.

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It is a clue that these rocks

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must once have been crushed by

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massive forces. And the colors

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support this theory. Under the

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polarized light, the sample

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from Inwood Hill Park shows up

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blue. This comes from a

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mineral called kyanite, which

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forms at great depths. It's

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conclusive evidence that this

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rock was compressed deep under

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the surface. Rocks forged at

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these depths are much harder,

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ideal for a city's

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foundations. But what gigantic

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weight was on top?

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Merguerian believes there is

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only one answer.

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The rock was once buried under

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the crushing weight of a chain

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of massive mountains.

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>> The minerals that we find

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in the bedrock units of New

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York City tell us that the

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rocks of New York City were

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formerly buried when they were

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formed, under very high

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pressures, and that those

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high pressures indicate that

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these rocks formerly were

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produced at depths of 20

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to 25 miles, and probably the

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mountains were as high as the

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Alps are today.

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>> But even the most

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impressive mountain chains

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can't survive the ravages of

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time. The Rocky Mountains, for

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example. Millions of years

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ago, they soared nearly six

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miles into the sky. Today,

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erosion has halved their size.

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The same process happened in

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New York. Rain, wind and ice

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wore the ancient mountains

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almost flat. But the

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microscopic crystals found in

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the rock in Manhattan testify

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that they existed in the past.

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How did the mountains form?

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The answer lies in the way the

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earth's crust moves.

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A network of

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interlocking individual

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pieces makes up the earth's

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surface. Geologists call them

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tectonic plates. Over millions

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of years, they collide and

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break apart to form different

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continents. 450 million years

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ago, the earth's surface

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looked completely different.

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North America was much further

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to the south.

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>> MERGUERIAN: North America

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was tilted 90 degrees clockwise

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from its present orientation and

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it was straddling the equator.

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As such, the climate was

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tropical, the east coast of

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North America was really

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experiencing Club Med

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conditions.

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>> The weather may have been

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awesome, but the ancient East

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Coast was heading for trouble.

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The plate beneath it was

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moving. The East Coast was on

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a collision course with

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ancient West Africa. 450

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million years ago, they

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collided. The impact unleashed

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geological chaos. Under

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intense compression, the land

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was forced upwards to form a

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soaring range of mountains.

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>> The collision that took

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place is the most fundamental

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and impressive

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mountain-building event to

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affect the east coast of North

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America.

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>> Today, all that remains are

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their stumps, stumps that form

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the bedrock of modern-day New

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York. The collision that built

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up the ancient mountains also

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folded the bedrock into dips

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and rises. These folds are

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responsible for the shape of

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Manhattan's skyline.

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The city boasts two clusters

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of skyscrapers in downtown and

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midtown. Here, the hard

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bedrock that formed deep

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underground was forced up.

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It is now close to the surface

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and provides solid anchorage

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for the high-rise buildings.

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In the dip in the middle the

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rock was folded down.

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The area is filled with loose

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sediments, less suitable for

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skyscrapers.

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>> MERGUERIAN: When the bedrock

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is at the earth's surface

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where it's actually exposed,

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then it's pretty easy

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to build tall buildings 'cause

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you can root them directly

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into solid rock.

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However, in areas where the

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bedrock is deep and covered by

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glacial sediment, in those

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cases, it's very difficult to

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build tall buildings because

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you need to root those

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buildings either into solid

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rock or build concrete

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abutments called caissons that

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can support tall buildings.

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>> New York's deep history is

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beginning to take shape.

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Building up from tiny crystals

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in the rock, scientists

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revealed how New York's

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bedrock was formed under the

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crushing weight of a massive

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ancient mountain range.

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The result was hard Manhattan

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schist, a perfect foundation

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for the city's skyscrapers.

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But New York City still had a

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long way to go.

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The colliding plates created

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an enormous landmass - the

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last great supercontinent,

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called Pangaea. New York was

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now trapped in the center...

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but somehow it made it back to

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the coast. Hidden beyond the

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city's streets is evidence of

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huge volcanic eruptions, mass

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extinctions and continents

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torn into pieces. Clues that

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could explain how New York

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became one of the world's

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great maritime cities.

290
00:10:56,066 --> 00:10:57,599
[]Investigators are piecing

291
00:10:57,667 --> 00:10:59,134
together how New York City's

292
00:10:59,235 --> 00:11:01,437
unique geology was formed.

293
00:11:03,473 --> 00:11:05,207
Much of its early success as a

294
00:11:05,275 --> 00:11:06,709
trade and commerce center is

295
00:11:06,743 --> 00:11:09,278
owed to its deep-water harbor

296
00:11:09,379 --> 00:11:11,547
and its location at the coast.

297
00:11:14,484 --> 00:11:16,618
But 450 million years ago,

298
00:11:16,653 --> 00:11:18,821
things were different.

299
00:11:18,888 --> 00:11:21,023
The area of New York City was

300
00:11:21,091 --> 00:11:23,192
landlocked, embedded in the

301
00:11:23,293 --> 00:11:24,093
heart of a huge

302
00:11:24,194 --> 00:11:27,062
supercontinent. How did it get

303
00:11:27,097 --> 00:11:29,098
to the coast? The

304
00:11:29,199 --> 00:11:31,000
investigation fast-forwards

305
00:11:31,101 --> 00:11:35,004
250 million years. In a quarry

306
00:11:35,105 --> 00:11:37,006
in New Jersey, 25 miles

307
00:11:37,073 --> 00:11:38,741
northeast of Manhattan,

308
00:11:38,808 --> 00:11:40,743
paleontologist Paul Olson

309
00:11:40,810 --> 00:11:42,478
unearths the first of a string

310
00:11:42,545 --> 00:11:44,446
of clues that could explain

311
00:11:44,514 --> 00:11:46,181
how New York City reached the

312
00:11:46,249 --> 00:11:49,451
coast. A giant fossilized

313
00:11:49,552 --> 00:11:50,719
footprint.

314
00:11:50,787 --> 00:11:51,987
>> This is the footprint,

315
00:11:52,022 --> 00:11:53,155
actually the mud that filled

316
00:11:53,189 --> 00:11:54,556
in the footprint, of a

317
00:11:54,657 --> 00:11:57,359
four-footed crocodile relative

318
00:11:57,427 --> 00:11:58,360
that was the dominant

319
00:11:58,428 --> 00:12:00,262
carnivore during the late

320
00:12:00,363 --> 00:12:02,331
Triassic. You can see the toes

321
00:12:02,365 --> 00:12:04,633
here have little pads on them

322
00:12:04,701 --> 00:12:06,335
and here's the handprint, and

323
00:12:06,369 --> 00:12:08,437
these animals would have been,

324
00:12:08,471 --> 00:12:09,738
in this case, about the size

325
00:12:09,806 --> 00:12:11,807
of a modest crocodile, but

326
00:12:11,908 --> 00:12:13,509
some of them became much, much

327
00:12:13,543 --> 00:12:16,078
larger, the size even of a T.

328
00:12:16,112 --> 00:12:18,080
Rex.

329
00:12:18,181 --> 00:12:20,449
[ROARS]

330
00:12:20,517 --> 00:12:21,784
>> The footprints are from a

331
00:12:21,818 --> 00:12:23,419
huge crocodile-like creature

332
00:12:23,453 --> 00:12:25,621
called Postosuchus.

333
00:12:25,722 --> 00:12:26,899
It first appeared on the earth

334
00:12:26,923 --> 00:12:30,626
around 230 million years ago.

335
00:12:30,693 --> 00:12:32,795
Then, some 30 million years

336
00:12:32,829 --> 00:12:34,897
later, its footprints suddenly

337
00:12:34,964 --> 00:12:37,266
vanished. But Postosuchus

338
00:12:37,333 --> 00:12:40,436
wasn't alone. Half of all land

339
00:12:40,470 --> 00:12:42,004
animals perished at the same

340
00:12:42,072 --> 00:12:44,907
time. The fossil evidence

341
00:12:45,008 --> 00:12:46,048
proves it to be one of the

342
00:12:46,076 --> 00:12:47,810
biggest mass extinctions ever

343
00:12:47,877 --> 00:12:49,545
recorded.

344
00:12:49,612 --> 00:12:50,913
>> The evidence for this mass

345
00:12:50,980 --> 00:12:52,614
extinction is that we have

346
00:12:52,715 --> 00:12:54,716
lots and lots of fossils right

347
00:12:54,818 --> 00:12:57,086
in this area. And what you see

348
00:12:57,153 --> 00:12:58,687
is especially in the--in the

349
00:12:58,721 --> 00:13:00,622
reptile footprints, you see

350
00:13:00,723 --> 00:13:03,092
one group of forms, the forms

351
00:13:03,159 --> 00:13:03,792
that are related to

352
00:13:03,893 --> 00:13:06,061
crocodilians, disappear.

353
00:13:08,731 --> 00:13:09,998
>> Whatever caused the mass

354
00:13:10,100 --> 00:13:11,433
extinction must have been a

355
00:13:11,534 --> 00:13:14,236
catastrophic event.

356
00:13:14,270 --> 00:13:15,904
Olsen had a hunch that the

357
00:13:16,005 --> 00:13:17,372
mass extinction was somehow

358
00:13:17,440 --> 00:13:19,274
related to New York's return

359
00:13:19,342 --> 00:13:22,911
to the coast.

360
00:13:22,979 --> 00:13:23,979
The ancient area

361
00:13:24,080 --> 00:13:25,914
of New York sat of a line of

362
00:13:25,982 --> 00:13:28,250
great weakness, the plate

363
00:13:28,351 --> 00:13:30,085
boundary where two continents

364
00:13:30,153 --> 00:13:31,320
joined to form the

365
00:13:31,354 --> 00:13:33,355
supercontinent Pangaea.

366
00:13:33,456 --> 00:13:36,158
And it was unstable, prone to

367
00:13:36,259 --> 00:13:38,794
earthquakes and volcanoes.

368
00:13:38,895 --> 00:13:40,963
Olsen's quest - to find the

369
00:13:40,997 --> 00:13:42,164
evidence for the natural

370
00:13:42,265 --> 00:13:43,532
disaster that finished off

371
00:13:43,633 --> 00:13:45,901
Postosuchus 200 million years

372
00:13:45,969 --> 00:13:48,971
ago.

373
00:13:49,072 --> 00:13:50,906
A band of dark rock above

374
00:13:50,974 --> 00:13:52,074
the footprints in the New

375
00:13:52,175 --> 00:13:55,444
Jersey quarry caught his eye.

376
00:13:55,512 --> 00:13:57,779
It was basalt, the smoking gun

377
00:13:57,814 --> 00:14:02,251
Olson was looking for.

378
00:14:02,352 --> 00:14:05,354
Basalt is a volcanic rock.

379
00:14:05,421 --> 00:14:07,356
It forms when hot lava erupts

380
00:14:07,423 --> 00:14:11,260
onto the surface and cools.

381
00:14:11,327 --> 00:14:13,262
Did the volcanoes that forged

382
00:14:13,329 --> 00:14:15,063
this basalt trigger the mass

383
00:14:15,165 --> 00:14:17,232
extinction and also rip

384
00:14:17,267 --> 00:14:21,803
Pangaea apart? On its own, the

385
00:14:21,905 --> 00:14:23,071
evidence at the quarry was

386
00:14:23,173 --> 00:14:25,073
unconvincing. The layer of

387
00:14:25,175 --> 00:14:27,809
basalt is only a few feet thick.

388
00:14:30,513 --> 00:14:31,980
To prove mass lava

389
00:14:32,048 --> 00:14:33,682
flows caused this global

390
00:14:33,716 --> 00:14:35,717
catastrophe, scientists needed

391
00:14:35,785 --> 00:14:37,886
corroborative evidence.

392
00:14:41,357 --> 00:14:42,991
High above the Hudson River,

393
00:14:43,059 --> 00:14:44,693
geologist Matt Gorring follows

394
00:14:44,761 --> 00:14:47,796
another lead. He's studying

395
00:14:47,864 --> 00:14:49,798
the Palisades, a dramatic

396
00:14:49,899 --> 00:14:51,700
geologic feature that hugs the

397
00:14:51,801 --> 00:14:53,435
Hudson River, beginning across

398
00:14:53,536 --> 00:14:55,604
mid Manhattan and running into

399
00:14:55,705 --> 00:14:58,874
northeast New Jersey.

400
00:14:58,942 --> 00:15:00,876
They too are made of basaltic

401
00:15:00,944 --> 00:15:03,345
rock, the same rock implicated

402
00:15:03,446 --> 00:15:05,080
in the mass extinction of land

403
00:15:05,148 --> 00:15:07,983
animals. But the Palisades are

404
00:15:08,051 --> 00:15:09,418
on an altogether different

405
00:15:09,519 --> 00:15:11,520
scale.

406
00:15:11,554 --> 00:15:13,589
>> The Palisades are a sheet

407
00:15:13,623 --> 00:15:17,426
of basaltic magma, about 1,000

408
00:15:17,527 --> 00:15:19,428
feet thick, it's about 40

409
00:15:19,529 --> 00:15:20,762
miles long, so it's a

410
00:15:20,797 --> 00:15:21,663
very prominent set

411
00:15:21,698 --> 00:15:22,965
of cliffs that run all the way

412
00:15:23,066 --> 00:15:24,210
up the west side of the Hudson

413
00:15:24,234 --> 00:15:27,336
River.

414
00:15:27,403 --> 00:15:29,338
>> Here is proof of massive

415
00:15:29,405 --> 00:15:33,609
volcanic activity. Hot lava

416
00:15:33,710 --> 00:15:35,077
flooded out of ruptures in the

417
00:15:35,144 --> 00:15:36,578
earth's crust and covered

418
00:15:36,613 --> 00:15:38,046
ancient North America in a

419
00:15:38,147 --> 00:15:42,584
mile-deep sheet. The lava

420
00:15:42,619 --> 00:15:45,487
cracked as it cooled. The

421
00:15:45,521 --> 00:15:46,788
vertical ruptures formed

422
00:15:46,889 --> 00:15:51,226
regular pencil-shaped columns.

423
00:15:51,294 --> 00:15:52,527
These distinctive rock

424
00:15:52,595 --> 00:15:54,029
formations have been known to

425
00:15:54,063 --> 00:15:55,931
geologists since the 19th

426
00:15:55,965 --> 00:15:59,568
century.

427
00:15:59,602 --> 00:16:00,969
Intriguingly, they

428
00:16:01,037 --> 00:16:02,504
appear on both sides of the

429
00:16:02,572 --> 00:16:04,973
Atlantic, in North and South

430
00:16:05,041 --> 00:16:08,777
America, Europe and Africa.

431
00:16:08,878 --> 00:16:10,512
Geologists suspected that

432
00:16:10,613 --> 00:16:11,880
their presence pointed to the

433
00:16:11,948 --> 00:16:13,515
spot where Africa and Europe

434
00:16:13,616 --> 00:16:17,586
separated from America.

435
00:16:17,687 --> 00:16:18,954
But that was just an unproven

436
00:16:19,022 --> 00:16:23,225
theory, until the 1950s, when

437
00:16:23,293 --> 00:16:24,526
scientists developed a

438
00:16:24,594 --> 00:16:26,295
revolutionary technique called

439
00:16:26,329 --> 00:16:29,698
paleomagnetism. Now, they

440
00:16:29,766 --> 00:16:30,866
could study the magnetic

441
00:16:30,933 --> 00:16:34,670
properties of rocks.

442
00:16:34,704 --> 00:16:36,672
Many rocks, including basalt,

443
00:16:36,706 --> 00:16:38,407
have a distinctive magnetic

444
00:16:38,508 --> 00:16:40,876
signature, formed as the rock

445
00:16:40,977 --> 00:16:44,112
is born. Tiny crystals inside

446
00:16:44,147 --> 00:16:45,681
the rock act like compass

447
00:16:45,782 --> 00:16:47,649
needles. When the magma that

448
00:16:47,684 --> 00:16:49,651
forms the rock is fluid, the

449
00:16:49,686 --> 00:16:51,153
crystals align to the earth's

450
00:16:51,220 --> 00:16:53,689
magnetic field, pointing north.

451
00:16:56,326 --> 00:16:57,959
As the rock solidifies,

452
00:16:58,027 --> 00:16:59,928
the crystals freeze, forever

453
00:16:59,962 --> 00:17:01,697
locked in that fixed magnetic

454
00:17:01,764 --> 00:17:05,400
alignment. As continents move

455
00:17:05,468 --> 00:17:06,968
and the rocks travel, the

456
00:17:07,036 --> 00:17:08,837
crystals end up pointing in a

457
00:17:08,871 --> 00:17:09,971
different direction than

458
00:17:10,039 --> 00:17:13,375
north. Gorring and his team

459
00:17:13,409 --> 00:17:14,676
investigate the magnetic

460
00:17:14,744 --> 00:17:17,045
signature of the Palisades.

461
00:17:20,583 --> 00:17:22,317
To get a sample, they bore

462
00:17:22,385 --> 00:17:23,218
into the rock with a

463
00:17:23,286 --> 00:17:25,120
water-cooled drill.

464
00:17:29,692 --> 00:17:30,926
They measure the exact

465
00:17:30,960 --> 00:17:32,461
orientation of the crystals

466
00:17:32,495 --> 00:17:35,030
today with a compass.

467
00:17:35,131 --> 00:17:36,598
When they offset this reading

468
00:17:36,666 --> 00:17:38,400
with magnetic north, they can

469
00:17:38,468 --> 00:17:39,601
calculate the original

470
00:17:39,669 --> 00:17:41,670
location of the rock.

471
00:17:41,704 --> 00:17:44,673
>> Uh...14.

472
00:17:44,741 --> 00:17:46,141
One of the useful things

473
00:17:46,209 --> 00:17:47,476
that you can do with this rock

474
00:17:47,510 --> 00:17:48,410
is you can take it back in the

475
00:17:48,511 --> 00:17:49,945
lab and measure its magnetic

476
00:17:50,046 --> 00:17:51,780
orientation, and that magnetic

477
00:17:51,848 --> 00:17:53,315
orientation will be

478
00:17:53,416 --> 00:17:54,783
when this rock crystallized or

479
00:17:54,851 --> 00:17:56,418
solidified 200 million years

480
00:17:56,452 --> 00:17:58,520
ago. So this rock would

481
00:17:58,621 --> 00:17:59,665
have minerals that would be

482
00:17:59,689 --> 00:18:00,522
pointing in some other

483
00:18:00,590 --> 00:18:01,990
direction other than north

484
00:18:02,058 --> 00:18:05,694
today.

485
00:18:05,728 --> 00:18:06,995
>> When scientists compared

486
00:18:07,096 --> 00:18:08,563
the magnetic orientation of

487
00:18:08,598 --> 00:18:10,132
the Palisades with the other

488
00:18:10,233 --> 00:18:11,666
basalt outcrops around the

489
00:18:11,768 --> 00:18:13,668
Atlantic, they discovered they

490
00:18:13,736 --> 00:18:15,036
formed at approximately the

491
00:18:15,104 --> 00:18:17,939
same latitude. Not only did

492
00:18:17,974 --> 00:18:19,608
the rocks have the same age,

493
00:18:19,675 --> 00:18:21,309
they were also born at the

494
00:18:21,411 --> 00:18:24,312
same location. For example,

495
00:18:24,414 --> 00:18:26,748
200 million years ago, New York

496
00:18:26,783 --> 00:18:29,017
and Morocco were neighbors.

497
00:18:34,056 --> 00:18:35,590
The geologists had all the

498
00:18:35,658 --> 00:18:38,059
proof they needed. They

499
00:18:38,127 --> 00:18:39,661
could now confidently piece

500
00:18:39,762 --> 00:18:43,498
together what happened.

501
00:18:43,566 --> 00:18:45,467
It began with a global

502
00:18:45,501 --> 00:18:48,103
volcanic disaster.

503
00:18:48,137 --> 00:18:49,471
>> About 200 million years

504
00:18:49,505 --> 00:18:51,006
ago, North America and

505
00:18:51,040 --> 00:18:52,374
Africa began to pull apart

506
00:18:52,408 --> 00:18:54,676
from each other.

507
00:18:54,777 --> 00:18:56,378
There were gigantic lava

508
00:18:56,412 --> 00:18:58,380
outpourings. These lava flows

509
00:18:58,414 --> 00:19:00,682
erupted along very long

510
00:19:00,750 --> 00:19:02,317
cracks in the earth's crust,

511
00:19:02,385 --> 00:19:03,318
that would have produced

512
00:19:03,386 --> 00:19:04,753
fountains of lava extending

513
00:19:04,854 --> 00:19:06,288
thousands and thousands of

514
00:19:06,322 --> 00:19:08,590
feet into the atmosphere.

515
00:19:10,593 --> 00:19:11,560
They covered an almost

516
00:19:11,594 --> 00:19:13,395
inconceivably large area,

517
00:19:13,463 --> 00:19:16,131
roughly four million square

518
00:19:16,232 --> 00:19:18,300
miles, from southwestern

519
00:19:18,367 --> 00:19:20,936
France to southwestern Brazil,

520
00:19:20,937 --> 00:19:23,104
from New York to central Mali

521
00:19:23,206 --> 00:19:24,940
in Africa. This area was

522
00:19:25,007 --> 00:19:27,209
covered in ponded lava flows

523
00:19:27,276 --> 00:19:28,910
that in some places ended up

524
00:19:28,945 --> 00:19:31,379
being nearly a mile thick.

525
00:19:35,017 --> 00:19:36,685
>> Volcanic eruptions led to

526
00:19:36,752 --> 00:19:38,620
soaring temperatures.

527
00:19:38,654 --> 00:19:40,255
Half of the plants and animals

528
00:19:40,289 --> 00:19:43,358
died. Postosuchus didn't stand

529
00:19:43,392 --> 00:19:47,662
a chance.

530
00:19:47,730 --> 00:19:49,564
As enormous forces

531
00:19:49,665 --> 00:19:51,833
tore Pangaea apart, a giant

532
00:19:51,934 --> 00:19:53,201
sea formed between the

533
00:19:53,302 --> 00:19:55,570
separating land masses - the

534
00:19:55,638 --> 00:19:58,540
Atlantic Ocean. The city of

535
00:19:58,608 --> 00:20:01,543
New York was now at the coast.

536
00:20:06,516 --> 00:20:08,083
200-million-year-old

537
00:20:08,150 --> 00:20:09,684
footprints beneath a layer of

538
00:20:09,719 --> 00:20:11,620
basalt and the Palisades

539
00:20:11,687 --> 00:20:14,122
towering above the Hudson

540
00:20:14,156 --> 00:20:16,124
provide evidence that Pangaea

541
00:20:16,158 --> 00:20:17,993
split apart to create the east

542
00:20:18,060 --> 00:20:21,329
coast of North America.

543
00:20:21,397 --> 00:20:23,131
But the story of New York City

544
00:20:23,165 --> 00:20:25,800
was far from over. After being

545
00:20:25,902 --> 00:20:27,702
built by fire, the region was

546
00:20:27,803 --> 00:20:29,437
about to be overcome by

547
00:20:29,505 --> 00:20:32,340
another destructive force.

548
00:20:38,436 --> 00:20:39,637
[]Scientists are piecing

549
00:20:39,704 --> 00:20:41,071
together the story of New

550
00:20:41,173 --> 00:20:42,606
York's violent geological

551
00:20:42,707 --> 00:20:45,709
past.

552
00:20:45,777 --> 00:20:47,711
250 million years ago,

553
00:20:47,813 --> 00:20:49,780
the Atlantic Ocean opened up,

554
00:20:49,815 --> 00:20:51,515
leaving the area of New York

555
00:20:51,616 --> 00:20:54,718
on the coast. But the maritime

556
00:20:54,786 --> 00:20:57,955
city still had a long way to go.

557
00:21:03,128 --> 00:21:04,628
There was no deep Hudson

558
00:21:04,696 --> 00:21:07,331
River channel. It was nothing

559
00:21:07,399 --> 00:21:11,602
but a small stream. What

560
00:21:11,703 --> 00:21:13,771
forces transformed it into the

561
00:21:13,805 --> 00:21:15,706
wide river capable of carrying

562
00:21:15,807 --> 00:21:18,542
heavy freighters far inland?

563
00:21:22,247 --> 00:21:23,714
A clue to how the Hudson

564
00:21:23,782 --> 00:21:25,516
Valley was created is the

565
00:21:25,617 --> 00:21:27,151
strange boulders that are

566
00:21:27,219 --> 00:21:27,985
scattered throughout

567
00:21:28,053 --> 00:21:30,788
Manhattan's Central Park.

568
00:21:30,856 --> 00:21:32,256
Some of them weigh several

569
00:21:32,357 --> 00:21:35,793
tons. But they're strangers to

570
00:21:35,861 --> 00:21:37,895
these parts, totally unlike

571
00:21:37,963 --> 00:21:40,331
the surrounding rocks.

572
00:21:42,534 --> 00:21:44,235
Geologist Charles Merguerian

573
00:21:44,302 --> 00:21:45,870
investigates where they came

574
00:21:45,971 --> 00:21:48,239
from.

575
00:21:48,340 --> 00:21:49,673
>> This boulder is a boulder

576
00:21:49,708 --> 00:21:50,975
from the Palisade sheet on

577
00:21:51,042 --> 00:21:52,243
the other side of the Hudson

578
00:21:52,310 --> 00:21:53,878
in New Jersey. You can see

579
00:21:53,979 --> 00:21:55,779
it's very nicely polished.

580
00:21:55,881 --> 00:21:57,248
Compositionally, it is totally

581
00:21:57,349 --> 00:21:58,392
different than the surrounding

582
00:21:58,416 --> 00:21:59,583
bedrock, which is Manhattan

583
00:21:59,618 --> 00:22:01,252
schist, and the Manhattan

584
00:22:01,319 --> 00:22:02,486
schist here is very rich in

585
00:22:02,520 --> 00:22:03,888
mica. This rock has no

586
00:22:03,989 --> 00:22:04,955
light-colored mica in it

587
00:22:04,990 --> 00:22:07,892
whatsoever. The Palisade sheet

588
00:22:07,959 --> 00:22:09,393
is located to the west and

589
00:22:09,427 --> 00:22:10,895
north of us.

590
00:22:14,799 --> 00:22:16,500
>> The Palisades run for 40

591
00:22:16,534 --> 00:22:19,870
miles along the Hudson River.

592
00:22:19,971 --> 00:22:22,039
Something immensely powerful

593
00:22:22,073 --> 00:22:23,507
must have moved the boulders

594
00:22:23,575 --> 00:22:27,411
such a great distance.

595
00:22:27,512 --> 00:22:29,980
Merguerian knows the answer

596
00:22:30,048 --> 00:22:31,782
is ice.

597
00:22:34,619 --> 00:22:35,686
Scientists have

598
00:22:35,754 --> 00:22:37,254
noticed a similar phenomenon

599
00:22:37,322 --> 00:22:39,156
4,000 miles away in

600
00:22:39,224 --> 00:22:43,227
the Swiss Alps. As huge

601
00:22:43,261 --> 00:22:44,662
glaciers grind their way

602
00:22:44,696 --> 00:22:46,297
across the landscape, they

603
00:22:46,331 --> 00:22:48,332
gouge out lumps of rock and

604
00:22:48,400 --> 00:22:50,067
carry them along in the base

605
00:22:50,135 --> 00:22:53,337
of the ice. These rocks act

606
00:22:53,405 --> 00:22:55,339
like sandpaper and carve out

607
00:22:55,407 --> 00:22:58,242
deep scratches. When the ice

608
00:22:58,310 --> 00:23:00,044
melts, it leaves the boulders

609
00:23:00,145 --> 00:23:04,248
behind. Merguerian is

610
00:23:04,316 --> 00:23:05,783
convinced the same thing

611
00:23:05,884 --> 00:23:08,319
happened in Central Park.

612
00:23:08,420 --> 00:23:09,954
Ice moved the Palisade

613
00:23:10,055 --> 00:23:11,221
boulders and carved out

614
00:23:11,323 --> 00:23:12,656
grooves in the bedrock

615
00:23:12,691 --> 00:23:14,692
underneath.

616
00:23:14,793 --> 00:23:15,960
>> This bedrock exposure in

617
00:23:16,061 --> 00:23:17,494
Central Park shows the

618
00:23:17,562 --> 00:23:19,496
profound effects of glaciation

619
00:23:19,597 --> 00:23:20,397
in the form of these

620
00:23:20,432 --> 00:23:22,566
spectacular glacial grooves

621
00:23:22,600 --> 00:23:24,702
that move up the outcrop and

622
00:23:24,769 --> 00:23:27,338
show this pattern where

623
00:23:27,405 --> 00:23:29,673
glaciers grabbed huge boulders

624
00:23:29,741 --> 00:23:31,408
and those huge boulders acted

625
00:23:31,476 --> 00:23:33,143
like tools to produce these

626
00:23:33,211 --> 00:23:34,211
scratches.

627
00:23:37,148 --> 00:23:38,849
>> To Merguerian, the rocks in

628
00:23:38,883 --> 00:23:40,317
Central Park are compelling

629
00:23:40,418 --> 00:23:42,152
evidence that New York once

630
00:23:42,220 --> 00:23:45,689
was covered in ice.

631
00:23:45,757 --> 00:23:47,324
Over millions of years,

632
00:23:47,425 --> 00:23:49,026
growing and receding ice has

633
00:23:49,060 --> 00:23:50,294
repeatedly turned North

634
00:23:50,328 --> 00:23:51,862
America into a frozen

635
00:23:51,930 --> 00:23:53,297
wilderness.

636
00:23:57,502 --> 00:23:58,869
But the grooves on the rocks

637
00:23:58,937 --> 00:24:00,604
in New York don't tell the

638
00:24:00,672 --> 00:24:03,774
full story. The destruction

639
00:24:03,875 --> 00:24:05,776
caused by the ice points to a

640
00:24:05,844 --> 00:24:07,945
gigantic glacial event that

641
00:24:08,046 --> 00:24:09,313
would dwarf the future

642
00:24:09,381 --> 00:24:11,215
metropolis.

643
00:24:13,685 --> 00:24:14,485
To find out the

644
00:24:14,552 --> 00:24:16,220
extent of the ice, Merguerian

645
00:24:16,321 --> 00:24:18,055
traveled to Bear Mountain,

646
00:24:18,123 --> 00:24:20,024
some 50 miles north of New

647
00:24:20,058 --> 00:24:21,392
York City.

648
00:24:24,596 --> 00:24:25,662
Once again, the

649
00:24:25,764 --> 00:24:28,632
clue was in the rocks. He

650
00:24:28,700 --> 00:24:30,567
found glacial marks similar

651
00:24:30,635 --> 00:24:34,271
to those in Central Park.

652
00:24:34,372 --> 00:24:35,516
>> What we're looking at here

653
00:24:35,540 --> 00:24:37,074
are chatter marks. Chatter

654
00:24:37,108 --> 00:24:38,842
marks are very diagnostic

655
00:24:38,910 --> 00:24:40,811
features of glacial erosion,

656
00:24:40,879 --> 00:24:43,013
they're produced by boulders

657
00:24:43,081 --> 00:24:44,248
embedded in the base of a

658
00:24:44,282 --> 00:24:46,083
thick sheet of glacial ice.

659
00:24:46,184 --> 00:24:48,018
Those boulders impinged on

660
00:24:48,086 --> 00:24:49,353
this bedrock surface,

661
00:24:49,454 --> 00:24:51,889
polishing it, smoothing it off

662
00:24:51,923 --> 00:24:53,457
and then plucking pieces of

663
00:24:53,558 --> 00:24:55,359
rock off as the glacial ice

664
00:24:55,427 --> 00:24:56,994
moved over with the boulders

665
00:24:57,062 --> 00:25:00,631
embedded in the base.

666
00:25:00,732 --> 00:25:02,032
>> T gouges in the rocks

667
00:25:02,067 --> 00:25:04,435
could mean just one thing.

668
00:25:04,502 --> 00:25:05,602
The glacier must have been

669
00:25:05,703 --> 00:25:08,338
thousands of feet thick.

670
00:25:08,406 --> 00:25:09,506
>> In this case, although

671
00:25:09,574 --> 00:25:10,774
we're standing at an elevation

672
00:25:10,842 --> 00:25:12,709
of about 1280 feet above sea

673
00:25:12,777 --> 00:25:14,978
level, the glacial ice sheet

674
00:25:15,046 --> 00:25:16,747
covered Bear Mountain as if it

675
00:25:16,781 --> 00:25:20,317
weren't even there.

676
00:25:20,418 --> 00:25:21,685
>> Scientists have found

677
00:25:21,753 --> 00:25:23,220
identical chatter marks on

678
00:25:23,254 --> 00:25:25,155
nearby peaks up to a mile

679
00:25:25,223 --> 00:25:27,291
above sea level. It was

680
00:25:27,325 --> 00:25:29,326
unmistakable proof.

681
00:25:29,427 --> 00:25:31,161
A glacier at least one mile

682
00:25:31,229 --> 00:25:33,230
thick ground its way across

683
00:25:33,298 --> 00:25:35,232
these mountains.

684
00:25:37,402 --> 00:25:39,503
Did this same ice sheet also

685
00:25:39,604 --> 00:25:41,872
plow through Central Park?

686
00:25:41,940 --> 00:25:43,674
Another nearby rock face

687
00:25:43,775 --> 00:25:45,976
provided the answer.

688
00:25:46,044 --> 00:25:46,977
>> The feature that we're

689
00:25:47,045 --> 00:25:48,089
looking at here are a series

690
00:25:48,113 --> 00:25:49,580
of sub-parallel glacial

691
00:25:49,614 --> 00:25:51,115
scratches and grooves and

692
00:25:51,149 --> 00:25:52,316
these are, again, are

693
00:25:52,383 --> 00:25:54,218
produced by the glacial ice

694
00:25:54,319 --> 00:25:56,053
sheet dragging boulders across

695
00:25:56,121 --> 00:25:57,521
this very durable granite

696
00:25:57,589 --> 00:25:59,490
surface, it's kind of polished

697
00:25:59,524 --> 00:26:01,158
the surface. And, in addition,

698
00:26:01,226 --> 00:26:02,292
it's produced these rather

699
00:26:02,327 --> 00:26:04,595
subtle but--but--but obvious,

700
00:26:04,696 --> 00:26:06,130
when the lighting is right,

701
00:26:06,231 --> 00:26:07,698
striae or grooves in the

702
00:26:07,765 --> 00:26:09,233
bedrock. Now if we measure the

703
00:26:09,334 --> 00:26:16,106
orientation of these,

704
00:26:16,141 --> 00:26:20,310
these--these come out about

705
00:26:20,411 --> 00:26:23,046
north 20 degrees west, just

706
00:26:23,148 --> 00:26:24,882
about identical in orientation

707
00:26:24,949 --> 00:26:26,150
to the striae that we measured

708
00:26:26,217 --> 00:26:29,653
at Central Park.

709
00:26:29,687 --> 00:26:31,488
>> It's significant evidence

710
00:26:31,556 --> 00:26:32,556
that the ice sheet that

711
00:26:32,590 --> 00:26:34,057
covered Bear Mountain also

712
00:26:34,125 --> 00:26:35,592
flowed over the surface of

713
00:26:35,660 --> 00:26:38,695
Central Park. Proof that New

714
00:26:38,763 --> 00:26:40,330
York City was covered by a

715
00:26:40,398 --> 00:26:42,332
glacier four times higher than

716
00:26:42,400 --> 00:26:44,968
the Empire State Building.

717
00:26:45,036 --> 00:26:45,969
>> MERGUERIAN: Just imagine

718
00:26:46,037 --> 00:26:48,238
glacial ice, a huge thick ice

719
00:26:48,306 --> 00:26:49,940
sheet over a mile thick,

720
00:26:50,008 --> 00:26:52,042
exerting tremendous pressure

721
00:26:52,110 --> 00:26:54,011
on the surface and sculpting

722
00:26:54,045 --> 00:26:55,579
the surface into the landscape

723
00:26:55,647 --> 00:26:59,416
that we see today.

724
00:26:59,484 --> 00:27:00,684
>> The ice sheet's crushing

725
00:27:00,752 --> 00:27:02,486
weight bulldozed everything in

726
00:27:02,554 --> 00:27:04,188
its path and cut through the

727
00:27:04,222 --> 00:27:05,489
remains of the ancient

728
00:27:05,557 --> 00:27:08,825
mountains. Before the ice

729
00:27:08,860 --> 00:27:10,127
arrived, the waters of the

730
00:27:10,228 --> 00:27:11,662
Hudson River had gently cut

731
00:27:11,763 --> 00:27:13,297
down through the landscape to

732
00:27:13,331 --> 00:27:17,201
form a V-shaped valley. But a

733
00:27:17,235 --> 00:27:19,002
mile-thick glacier takes no

734
00:27:19,070 --> 00:27:22,239
prisoners. It gouged out the

735
00:27:22,307 --> 00:27:23,574
sides and the bottom of the

736
00:27:23,675 --> 00:27:24,775
river valley and turned it

737
00:27:24,842 --> 00:27:29,213
into a U-shaped riverbed.

738
00:27:29,314 --> 00:27:30,781
The Hudson River was now

739
00:27:30,848 --> 00:27:35,485
navigable for big ships.

740
00:27:35,553 --> 00:27:37,054
The picture of modern-day New

741
00:27:37,121 --> 00:27:39,590
York was almost complete.

742
00:27:41,759 --> 00:27:43,493
Long grooves in the rocks in

743
00:27:43,561 --> 00:27:45,462
Central Park showed scientists

744
00:27:45,496 --> 00:27:47,130
that a vast ice sheet flowed

745
00:27:47,198 --> 00:27:48,732
over the eroded remains of

746
00:27:48,766 --> 00:27:51,668
these mountains. And marks and

747
00:27:51,736 --> 00:27:53,270
glacial striations on Bear

748
00:27:53,304 --> 00:27:55,138
Mountain proved this ice sheet

749
00:27:55,206 --> 00:27:56,773
was at least four times higher

750
00:27:56,841 --> 00:27:58,942
than the Empire State Building.

751
00:28:02,180 --> 00:28:03,280
When the ice melted,

752
00:28:03,314 --> 00:28:05,449
it left a vast ridge of debris

753
00:28:05,483 --> 00:28:06,850
blocking the Hudson River from

754
00:28:06,951 --> 00:28:10,320
the Atlantic. The final

755
00:28:10,388 --> 00:28:12,122
challenge for geologists was

756
00:28:12,223 --> 00:28:13,657
to find out how the ridge was

757
00:28:13,725 --> 00:28:15,726
destroyed and how New York's

758
00:28:15,760 --> 00:28:18,729
harbor opened to the oceans.

759
00:28:27,964 --> 00:28:29,764
[]New York today boasts one of

760
00:28:29,799 --> 00:28:31,533
the largest natural harbors in

761
00:28:31,567 --> 00:28:34,002
the world. But it wasn't

762
00:28:34,036 --> 00:28:36,738
always that way. Towards the

763
00:28:36,839 --> 00:28:38,573
end of the last Ice Age, the

764
00:28:38,641 --> 00:28:40,108
port's wide entrance was

765
00:28:40,209 --> 00:28:44,212
blocked. 16,000 years ago, the

766
00:28:44,280 --> 00:28:45,947
melting glaciers left behind a

767
00:28:46,015 --> 00:28:49,484
220-foot-high wall of debris.

768
00:28:49,552 --> 00:28:50,852
The ridge stretched from Long

769
00:28:50,920 --> 00:28:52,654
Island to Staten Island and

770
00:28:52,722 --> 00:28:53,922
forced the Hudson River

771
00:28:53,990 --> 00:28:55,123
through a narrow, more

772
00:28:55,191 --> 00:28:59,294
westerly course to the ocean.

773
00:28:59,395 --> 00:29:01,630
What powerful forces destroyed

774
00:29:01,664 --> 00:29:04,733
this rock jam? The prime

775
00:29:04,800 --> 00:29:07,202
suspect was a flash flood.

776
00:29:10,573 --> 00:29:12,440
But scientists needed evidence

777
00:29:12,475 --> 00:29:14,342
to prove that such a flood had

778
00:29:14,377 --> 00:29:18,079
happened. In the 1960s,

779
00:29:18,114 --> 00:29:19,814
fishermen made an unexpected

780
00:29:19,849 --> 00:29:21,016
find at the mouth of the

781
00:29:21,083 --> 00:29:24,085
Hudson River. They dredged up

782
00:29:24,120 --> 00:29:26,354
a giant mammoth tusk from the

783
00:29:26,389 --> 00:29:28,723
depths of the sea floor.

784
00:29:28,758 --> 00:29:31,393
[TRUMPETS]

785
00:29:34,463 --> 00:29:36,364
Herds of these giant beasts

786
00:29:36,432 --> 00:29:37,599
roamed the plains of North

787
00:29:37,633 --> 00:29:39,367
America before they became

788
00:29:39,468 --> 00:29:41,002
extinct at the end of the

789
00:29:41,103 --> 00:29:43,338
last Ice Age.

790
00:29:47,910 --> 00:29:48,843
Finding the odd

791
00:29:48,911 --> 00:29:50,645
mammoth tusk here and there's

792
00:29:50,713 --> 00:29:52,981
not so surprising. But since

793
00:29:53,015 --> 00:29:54,349
the initial discovery,

794
00:29:54,383 --> 00:29:56,117
scientists have found hundreds

795
00:29:56,185 --> 00:29:58,186
more tusks and bones in the

796
00:29:58,287 --> 00:30:00,722
mouth of the Hudson River.

797
00:30:00,790 --> 00:30:02,357
It was as though a violent

798
00:30:02,391 --> 00:30:03,925
torrent swept the mammoths

799
00:30:03,993 --> 00:30:05,894
away and dumped their remains

800
00:30:05,928 --> 00:30:08,630
off the coast. And there were

801
00:30:08,698 --> 00:30:11,099
more clues nearby.

802
00:30:13,836 --> 00:30:15,837
Huge boulders resting on the

803
00:30:15,905 --> 00:30:20,175
sandy sea floor, some of them

804
00:30:20,242 --> 00:30:24,179
as big as cars. The boulders

805
00:30:24,246 --> 00:30:25,286
must have been part of the

806
00:30:25,348 --> 00:30:27,015
ancient moraine that once ran

807
00:30:27,083 --> 00:30:28,817
between Long Island and Staten

808
00:30:28,884 --> 00:30:33,621
Island. Geologist David Franzi

809
00:30:33,656 --> 00:30:35,156
knows that only a raging

810
00:30:35,191 --> 00:30:38,259
torrent could have shifted them.

811
00:30:38,294 --> 00:30:39,374
>> Based on the size of the

812
00:30:39,462 --> 00:30:41,529
boulders that we see here, we

813
00:30:41,564 --> 00:30:42,607
know that that flood must have

814
00:30:42,631 --> 00:30:45,333
discharged on the order of 1.5

815
00:30:45,368 --> 00:30:48,903
million cubic feet per second.

816
00:30:49,004 --> 00:30:50,472
That's three times larger than

817
00:30:50,539 --> 00:30:51,706
the largest Mississippi River

818
00:30:51,741 --> 00:30:54,075
flood ever recorded.

819
00:30:54,176 --> 00:30:55,744
>> And all that water had to

820
00:30:55,811 --> 00:30:58,246
come from somewhere.

821
00:30:58,280 --> 00:31:00,014
Scientists began looking for

822
00:31:00,082 --> 00:31:01,716
the source of this flood, a

823
00:31:01,817 --> 00:31:03,418
flood powerful enough to

824
00:31:03,452 --> 00:31:05,353
transport huge boulders all

825
00:31:05,454 --> 00:31:07,455
the way to the sea.

826
00:31:07,523 --> 00:31:08,456
>> Rocks to a geologist are

827
00:31:08,524 --> 00:31:10,425
like pages in a history book.

828
00:31:10,459 --> 00:31:12,994
For us, erosion oftentimes

829
00:31:13,062 --> 00:31:14,172
rips some of the pages out of

830
00:31:14,196 --> 00:31:15,797
our history book, so it's the

831
00:31:15,831 --> 00:31:17,365
job of the geologist to put

832
00:31:17,433 --> 00:31:18,800
together a fragmentary record

833
00:31:18,834 --> 00:31:20,435
into a coherent history of the

834
00:31:20,469 --> 00:31:21,269
events that happened in the

835
00:31:21,370 --> 00:31:23,905
past.

836
00:31:24,006 --> 00:31:25,640
>> 300 miles north of the

837
00:31:25,708 --> 00:31:27,876
city, in upstate New York,

838
00:31:27,910 --> 00:31:29,244
Franzi tracked what might have

839
00:31:29,278 --> 00:31:30,879
been the flood's path to an

840
00:31:30,913 --> 00:31:32,614
unusual grove of trees on

841
00:31:32,648 --> 00:31:34,516
Covey Hill in the Adirondack

842
00:31:34,550 --> 00:31:37,986
Mountains.

843
00:31:38,087 --> 00:31:41,256
The trees are jack pines.

844
00:31:41,357 --> 00:31:42,824
They are rare in this area,

845
00:31:42,892 --> 00:31:44,259
where the soil is usually

846
00:31:44,360 --> 00:31:48,263
fertile and deep. But on Covey

847
00:31:48,330 --> 00:31:49,964
Hill, their presence shows

848
00:31:49,999 --> 00:31:51,266
that there is no more than a

849
00:31:51,333 --> 00:31:53,268
few inches of soil on top of

850
00:31:53,335 --> 00:31:55,503
the bedrock.

851
00:31:55,538 --> 00:31:56,504
>> The jack pine is

852
00:31:56,539 --> 00:31:57,705
essentially rooted right

853
00:31:57,773 --> 00:31:58,606
out on the top of a rock's

854
00:31:58,641 --> 00:32:00,642
surface here. This is a bare

855
00:32:00,709 --> 00:32:02,410
sandstone surface, very little

856
00:32:02,445 --> 00:32:04,446
mineral soil, and it's subject

857
00:32:04,547 --> 00:32:05,747
to prolonged periods of

858
00:32:05,815 --> 00:32:07,549
dryness during the summertime.

859
00:32:07,616 --> 00:32:09,184
Jack pine's adaptations make

860
00:32:09,251 --> 00:32:10,618
it able to survive here where

861
00:32:10,719 --> 00:32:14,789
no other tree species can.

862
00:32:14,824 --> 00:32:16,958
>> What happened to the soil?

863
00:32:19,395 --> 00:32:20,929
The jack pines continue to

864
00:32:20,963 --> 00:32:22,664
grow at the entrance of a long

865
00:32:22,765 --> 00:32:26,768
gorge over 300 feet wide.

866
00:32:26,836 --> 00:32:28,603
Usually, gorges like this are

867
00:32:28,671 --> 00:32:30,004
cut down over thousands of

868
00:32:30,039 --> 00:32:32,140
years, but in this case, the

869
00:32:32,208 --> 00:32:34,042
missing topsoil points to a

870
00:32:34,109 --> 00:32:36,411
sudden flood event. A raging

871
00:32:36,479 --> 00:32:38,213
torrent must have ripped away

872
00:32:38,314 --> 00:32:40,114
the soil and cut deep into the

873
00:32:40,149 --> 00:32:42,317
rock.

874
00:32:46,021 --> 00:32:47,589
>> In a helicopter, Franzi

875
00:32:47,656 --> 00:32:52,093
follows the gorge west.

876
00:32:52,127 --> 00:32:53,728
Eventually, it opens into a

877
00:32:53,762 --> 00:32:56,130
vast, empty basin located

878
00:32:56,198 --> 00:32:57,232
next to one of the Great

879
00:32:57,299 --> 00:33:00,134
Lakes, Lake Ontario.

880
00:33:00,236 --> 00:33:02,003
>> It doesn't take much of a

881
00:33:02,037 --> 00:33:03,104
stretch of the imagination

882
00:33:03,138 --> 00:33:04,873
here to imagine this valley

883
00:33:04,940 --> 00:33:07,942
filled with water and then

884
00:33:08,043 --> 00:33:09,210
with these hills poking up

885
00:33:09,311 --> 00:33:11,846
through as islands.

886
00:33:11,947 --> 00:33:14,215
>> 16,000 years ago, this

887
00:33:14,283 --> 00:33:16,050
basin was filled with two

888
00:33:16,118 --> 00:33:18,820
billion cubic miles of water -

889
00:33:18,854 --> 00:33:21,189
a huge lake geologists call

890
00:33:21,223 --> 00:33:23,591
Lake Iroquois. It formed at

891
00:33:23,659 --> 00:33:25,760
the end of the last Ice Age.

892
00:33:28,998 --> 00:33:31,032
As glaciers receded, the melt

893
00:33:31,100 --> 00:33:32,734
waters slowly filled up the

894
00:33:32,768 --> 00:33:35,837
lake. The ice dams holding the

895
00:33:35,938 --> 00:33:38,740
waters weakened. Eventually,

896
00:33:38,774 --> 00:33:40,675
the dams collapsed, causing

897
00:33:40,743 --> 00:33:42,176
sudden and devastating

898
00:33:42,211 --> 00:33:45,113
flash floods.

899
00:33:45,214 --> 00:33:46,258
>> Lake level dropped on the

900
00:33:46,282 --> 00:33:49,651
order of 70 feet and about 160

901
00:33:49,685 --> 00:33:50,952
cubic miles of water were

902
00:33:51,020 --> 00:33:52,287
released into the Champlain

903
00:33:52,388 --> 00:33:53,755
Valley, catastrophically.

904
00:33:53,822 --> 00:33:55,023
That floodwater would have

905
00:33:55,124 --> 00:33:56,591
coursed down the Champlain

906
00:33:56,659 --> 00:33:58,359
Valley, through the Hudson

907
00:33:58,427 --> 00:33:59,794
Valley and ultimately out into

908
00:33:59,828 --> 00:34:02,363
the Atlantic Ocean.

909
00:34:02,464 --> 00:34:03,731
>> The torrent raced towards

910
00:34:03,799 --> 00:34:05,800
New York City, 300 miles to

911
00:34:05,868 --> 00:34:07,702
the south, then took the

912
00:34:07,736 --> 00:34:10,905
straightest course to the sea.

913
00:34:11,006 --> 00:34:12,507
The floodwaters smashed into

914
00:34:12,541 --> 00:34:14,509
the ancient moraine, the huge

915
00:34:14,543 --> 00:34:16,177
pile of debris blocking the

916
00:34:16,278 --> 00:34:17,645
direct exit of the Hudson

917
00:34:17,713 --> 00:34:20,081
River.

918
00:34:23,552 --> 00:34:25,186
>> The bridge we see behind me

919
00:34:25,254 --> 00:34:26,431
spans the channel that was cut

920
00:34:26,455 --> 00:34:28,690
by the flood event. When the

921
00:34:28,724 --> 00:34:30,091
flood wave came through, it

922
00:34:30,159 --> 00:34:31,960
was of sufficient intensity to

923
00:34:31,994 --> 00:34:33,161
over-top the dam and very

924
00:34:33,228 --> 00:34:35,263
rapidly cut the channel.

925
00:34:37,866 --> 00:34:39,334
>> The gap that was created by

926
00:34:39,368 --> 00:34:42,070
the flood still exists. It's

927
00:34:42,137 --> 00:34:43,905
now a tidal strait called

928
00:34:43,973 --> 00:34:48,443
the Narrows. Today, the gap is

929
00:34:48,510 --> 00:34:49,911
spanned by the Verrazano

930
00:34:49,979 --> 00:34:52,447
Bridge. The channel is deep

931
00:34:52,514 --> 00:34:53,781
enough for even the biggest

932
00:34:53,816 --> 00:34:56,150
ocean-going ships. It's the

933
00:34:56,185 --> 00:34:57,952
most important entrance to New

934
00:34:57,987 --> 00:34:59,821
York City's harbor.

935
00:35:03,626 --> 00:35:05,426
Mammoth tusks and huge

936
00:35:05,494 --> 00:35:06,794
boulders at the mouth of the

937
00:35:06,862 --> 00:35:08,429
river showed scientists that

938
00:35:08,530 --> 00:35:10,264
there was a torrent big enough

939
00:35:10,332 --> 00:35:11,532
to blast a hole through the

940
00:35:11,600 --> 00:35:14,235
ancient moraine. And a channel

941
00:35:14,269 --> 00:35:15,603
leading towards the Great

942
00:35:15,638 --> 00:35:17,271
Lakes revealed the source of

943
00:35:17,339 --> 00:35:19,707
the flood. It was this flood

944
00:35:19,808 --> 00:35:21,409
that created the Narrows and

945
00:35:21,443 --> 00:35:23,544
gave New York a wide entrance

946
00:35:23,612 --> 00:35:27,582
to its port. A unique geology

947
00:35:27,616 --> 00:35:29,450
laid down the foundations for

948
00:35:29,518 --> 00:35:31,252
New York City.

949
00:35:34,256 --> 00:35:35,790
But the same forces that

950
00:35:35,891 --> 00:35:37,225
constructed it may

951
00:35:37,259 --> 00:35:38,960
also have sown the seeds for

952
00:35:38,994 --> 00:35:41,529
New York's destruction.

953
00:35:47,784 --> 00:35:49,017
[]Scientists have pieced

954
00:35:49,052 --> 00:35:50,519
together the half-billion-year

955
00:35:50,587 --> 00:35:53,956
history of New York City.

956
00:35:54,023 --> 00:35:56,291
Huge mountains, volcanic

957
00:35:56,326 --> 00:35:58,327
eruptions and glacial ice

958
00:35:58,395 --> 00:36:00,863
shaped the area. But New

959
00:36:00,964 --> 00:36:03,132
York's story doesn't end here.

960
00:36:06,236 --> 00:36:08,137
The geology that created one

961
00:36:08,204 --> 00:36:09,471
of the greatest cities on

962
00:36:09,506 --> 00:36:11,607
earth also has the potential

963
00:36:11,674 --> 00:36:15,778
to destroy it.

964
00:36:15,845 --> 00:36:17,146
Experts have been studying the

965
00:36:17,213 --> 00:36:19,415
potential threat to the city.

966
00:36:19,516 --> 00:36:20,416
>> We're standing here in

967
00:36:20,517 --> 00:36:21,784
Lower Manhattan on one of our

968
00:36:21,851 --> 00:36:23,152
major thoroughfares, Canal

969
00:36:23,219 --> 00:36:24,787
Street. And it's important,

970
00:36:24,854 --> 00:36:27,289
because in 1821, a Category 2

971
00:36:27,323 --> 00:36:29,324
hurricane raised the water

972
00:36:29,392 --> 00:36:31,226
level at the Battery 13 feet

973
00:36:31,294 --> 00:36:33,695
in one hour and, literally,

974
00:36:33,763 --> 00:36:35,764
the Hudson River met the East

975
00:36:35,865 --> 00:36:38,300
River and Canal Street was

976
00:36:38,401 --> 00:36:39,935
covered by water and Manhattan

977
00:36:39,969 --> 00:36:41,670
was actually two islands for

978
00:36:41,738 --> 00:36:43,872
three hours, until the water

979
00:36:43,940 --> 00:36:47,776
receded.

980
00:36:47,844 --> 00:36:49,511
>> New York City is vulnerable

981
00:36:49,579 --> 00:36:50,946
because of its position on the

982
00:36:51,047 --> 00:36:54,850
coast.

983
00:36:54,918 --> 00:36:56,318
Long Island stretches

984
00:36:56,386 --> 00:36:58,053
northeast at a right angle

985
00:36:58,121 --> 00:37:00,689
from the New Jersey shore.

986
00:37:00,790 --> 00:37:02,124
New York City is nestled

987
00:37:02,192 --> 00:37:03,959
behind the western end of Long

988
00:37:04,027 --> 00:37:06,295
Island. Normally, the island

989
00:37:06,329 --> 00:37:07,496
protects the city from the

990
00:37:07,564 --> 00:37:09,765
sea, but when hurricanes

991
00:37:09,866 --> 00:37:11,567
threaten, the opposite is

992
00:37:11,601 --> 00:37:14,136
true. Long Island becomes a

993
00:37:14,204 --> 00:37:16,138
dangerous liability.

994
00:37:18,408 --> 00:37:20,375
Hurricanes racing north along

995
00:37:20,410 --> 00:37:21,677
the beaches of the Atlantic

996
00:37:21,744 --> 00:37:23,479
coast pile up huge bulges

997
00:37:23,546 --> 00:37:25,581
of water in front of them.

998
00:37:25,682 --> 00:37:28,951
They're called storm surges.

999
00:37:29,018 --> 00:37:30,018
Hitting the right-angled

1000
00:37:30,119 --> 00:37:31,386
junction at Long Island,

1001
00:37:31,488 --> 00:37:32,821
the winds funnel the storm

1002
00:37:32,856 --> 00:37:34,957
surge in through the Narrows,

1003
00:37:35,024 --> 00:37:36,592
the gap between Long Island

1004
00:37:36,659 --> 00:37:38,460
and New Jersey.

1005
00:37:38,495 --> 00:37:40,128
>> This is the place, at the

1006
00:37:40,230 --> 00:37:42,130
actual apex of the right angle

1007
00:37:42,198 --> 00:37:43,665
in New York where all the

1008
00:37:43,733 --> 00:37:45,000
water being pushed by a

1009
00:37:45,034 --> 00:37:45,834
hurricane would be

1010
00:37:45,935 --> 00:37:47,569
concentrated. And in the

1011
00:37:47,637 --> 00:37:49,137
distance is the Verrazano

1012
00:37:49,205 --> 00:37:51,106
Bridge, and all that water

1013
00:37:51,140 --> 00:37:52,207
is gonna go through the

1014
00:37:52,275 --> 00:37:53,742
passage we call the Narrows

1015
00:37:53,776 --> 00:37:55,177
and it's gonna be accelerated

1016
00:37:55,211 --> 00:37:56,945
towards New York City, where

1017
00:37:57,013 --> 00:37:58,680
it will rise to abnormal

1018
00:37:58,748 --> 00:38:00,315
heights.

1019
00:38:05,755 --> 00:38:07,222
>> Experts believe that in the

1020
00:38:07,290 --> 00:38:09,224
United States, New York is

1021
00:38:09,292 --> 00:38:11,360
the third most vulnerable city

1022
00:38:11,394 --> 00:38:13,295
after Miami and New Orleans

1023
00:38:13,396 --> 00:38:16,565
to a hurricane disaster. If it

1024
00:38:16,633 --> 00:38:18,033
was hit today, the

1025
00:38:18,134 --> 00:38:20,669
consequences would be serious.

1026
00:38:20,737 --> 00:38:22,838
>> New York City is hit by

1027
00:38:22,906 --> 00:38:25,541
hurricanes only infrequently.

1028
00:38:25,575 --> 00:38:29,278
Like, in 1821 and in 1893 and

1029
00:38:29,312 --> 00:38:32,714
in 1938. However, the point is

1030
00:38:32,749 --> 00:38:34,449
that the hurricane that will

1031
00:38:34,484 --> 00:38:36,118
eventually hit New York City

1032
00:38:36,219 --> 00:38:38,854
again will be catastrophic,

1033
00:38:38,922 --> 00:38:40,122
and what is going to happen

1034
00:38:40,189 --> 00:38:41,367
when the utilities are knocked

1035
00:38:41,391 --> 00:38:42,858
out? What is going to happen

1036
00:38:42,926 --> 00:38:44,560
when salt water reaches into

1037
00:38:44,661 --> 00:38:46,995
the subways and ruins the

1038
00:38:47,030 --> 00:38:48,297
electrical system? We're

1039
00:38:48,364 --> 00:38:49,631
talking about unbelievable

1040
00:38:49,666 --> 00:38:51,099
amounts of money to restore

1041
00:38:51,200 --> 00:38:52,734
the infrastructure. We're

1042
00:38:52,835 --> 00:38:54,736
talking about setbacks and

1043
00:38:54,804 --> 00:38:56,204
delays in commerce and

1044
00:38:56,306 --> 00:38:58,373
banking and transportation,

1045
00:38:58,474 --> 00:38:59,841
a catastrophe that's never

1046
00:38:59,943 --> 00:39:01,843
been seen.

1047
00:39:04,581 --> 00:39:06,081
>> Storm surges are not the

1048
00:39:06,115 --> 00:39:07,482
only threat to New York's

1049
00:39:07,550 --> 00:39:10,752
future.

1050
00:39:10,853 --> 00:39:12,654
Earthquakes are also part of

1051
00:39:12,755 --> 00:39:14,489
the vast geological forces

1052
00:39:14,557 --> 00:39:16,358
that shape this area.

1053
00:39:16,392 --> 00:39:18,894
They are still at work today.

1054
00:39:21,297 --> 00:39:23,198
Some could change the city

1055
00:39:23,299 --> 00:39:25,033
in an instant.

1056
00:39:27,470 --> 00:39:31,206
November 4th 1884. New York

1057
00:39:31,274 --> 00:39:32,741
City was shaken by an

1058
00:39:32,842 --> 00:39:34,109
earthquake that lasted ten

1059
00:39:34,177 --> 00:39:36,812
seconds. The Brooklyn Bridge

1060
00:39:36,846 --> 00:39:39,915
swayed and people panicked.

1061
00:39:39,983 --> 00:39:42,284
The earthquake showed 5.5

1062
00:39:42,385 --> 00:39:45,554
on the Richter scale.

1063
00:39:45,655 --> 00:39:49,191
January 17th 2001, New York

1064
00:39:49,292 --> 00:39:52,661
City was struck again.

1065
00:39:52,729 --> 00:39:53,895
This time the quake was

1066
00:39:53,963 --> 00:39:57,065
relatively small, only 2.4,

1067
00:39:57,133 --> 00:39:58,600
but it struck right under

1068
00:39:58,701 --> 00:40:01,770
125th Street.

1069
00:40:01,804 --> 00:40:04,706
>> The earthquake in 2001 is

1070
00:40:04,774 --> 00:40:06,174
the first earthquake that we

1071
00:40:06,242 --> 00:40:08,610
could confidently locate in

1072
00:40:08,711 --> 00:40:11,780
Manhattan, that's its claim to

1073
00:40:11,848 --> 00:40:14,349
fame, it was felt widely.

1074
00:40:24,260 --> 00:40:25,594
>> It's impossible to study

1075
00:40:25,695 --> 00:40:27,029
the cause of the quakes at the

1076
00:40:27,063 --> 00:40:30,432
surface.

1077
00:40:30,500 --> 00:40:31,233
The evidence is

1078
00:40:31,300 --> 00:40:33,702
buried beneath the city.

1079
00:40:36,506 --> 00:40:37,606
Deep within New York's

1080
00:40:37,674 --> 00:40:40,208
bedrock, seismologist Leonardo

1081
00:40:40,243 --> 00:40:41,877
Seeber studies the cause of

1082
00:40:41,978 --> 00:40:44,613
these quakes.

1083
00:40:44,681 --> 00:40:46,415
[HORN BLARES]

1084
00:40:48,851 --> 00:40:50,686
In a subway tunnel 100 feet

1085
00:40:50,753 --> 00:40:51,987
beneath the bedrock under the

1086
00:40:52,055 --> 00:40:53,488
East River, there is a

1087
00:40:53,523 --> 00:40:56,525
ready-made laboratory. Here,

1088
00:40:56,592 --> 00:40:58,260
Seeber can study the rocks up

1089
00:40:58,327 --> 00:41:01,763
close and personal.

1090
00:41:01,798 --> 00:41:03,432
It is the same bedrock

1091
00:41:03,499 --> 00:41:05,867
Manhattan is built on.

1092
00:41:05,968 --> 00:41:07,703
But Seeber fears it isn't as

1093
00:41:07,770 --> 00:41:11,206
solid as once was thought.

1094
00:41:11,240 --> 00:41:14,943
>> New York area is considered

1095
00:41:14,977 --> 00:41:17,879
a seismic zone, meaning there

1096
00:41:17,980 --> 00:41:20,048
is a cluster of known

1097
00:41:20,116 --> 00:41:21,316
earthquakes that have occurred

1098
00:41:21,417 --> 00:41:23,952
in this area. So we are, as

1099
00:41:24,053 --> 00:41:26,121
geologists, very eager to

1100
00:41:26,155 --> 00:41:27,689
discover which faults

1101
00:41:27,790 --> 00:41:29,024
are responsible for these

1102
00:41:29,058 --> 00:41:31,860
earthquakes.

1103
00:41:31,961 --> 00:41:33,161
>> The majority of earthquakes

1104
00:41:33,229 --> 00:41:34,596
occur at the boundaries

1105
00:41:34,664 --> 00:41:36,131
between separate sections of

1106
00:41:36,232 --> 00:41:37,499
the earth's crust, the

1107
00:41:37,600 --> 00:41:39,201
tectonic plates on which the

1108
00:41:39,235 --> 00:41:42,971
continents sit. But New York's

1109
00:41:43,039 --> 00:41:45,040
earthquakes are different.

1110
00:41:45,108 --> 00:41:46,508
The city is firmly in the

1111
00:41:46,576 --> 00:41:48,243
middle of a tectonic plate,

1112
00:41:48,311 --> 00:41:49,511
halfway between the

1113
00:41:49,612 --> 00:41:51,379
mid-Atlantic ridge to the east

1114
00:41:51,414 --> 00:41:52,948
and the San Andreas Fault to

1115
00:41:53,015 --> 00:41:57,018
the west.

1116
00:41:57,053 --> 00:41:58,587
Seeber is anxious to

1117
00:41:58,654 --> 00:42:01,690
discover what's going on.

1118
00:42:01,758 --> 00:42:03,058
As he examines the walls of

1119
00:42:03,126 --> 00:42:04,693
the tunnel, he comes across a

1120
00:42:04,761 --> 00:42:08,196
possible clue. The long

1121
00:42:08,231 --> 00:42:09,598
fractures in the rock are

1122
00:42:09,699 --> 00:42:11,399
fault lines that formed when

1123
00:42:11,467 --> 00:42:14,035
pressure built up. As the

1124
00:42:14,137 --> 00:42:15,937
tension was released, the rock

1125
00:42:15,972 --> 00:42:18,673
cracked and shifted. This is

1126
00:42:18,775 --> 00:42:20,375
felt on the surface as an

1127
00:42:20,409 --> 00:42:21,743
earthquake.

1128
00:42:21,778 --> 00:42:22,744
>> SEEBER: This is an example

1129
00:42:22,779 --> 00:42:25,147
of a very small fault, but

1130
00:42:25,214 --> 00:42:28,049
it's a fault that probably did

1131
00:42:28,117 --> 00:42:29,017
generate some small

1132
00:42:29,051 --> 00:42:31,119
earthquakes. When one of these

1133
00:42:31,154 --> 00:42:32,120
faults generates an

1134
00:42:32,155 --> 00:42:34,222
earthquake, we think that

1135
00:42:34,323 --> 00:42:36,124
perhaps other faults of the

1136
00:42:36,225 --> 00:42:37,492
same family can generate

1137
00:42:37,593 --> 00:42:41,396
earthquakes.

1138
00:42:41,464 --> 00:42:42,764
>> These faults in New York's

1139
00:42:42,832 --> 00:42:44,399
bedrock are evidence that the

1140
00:42:44,467 --> 00:42:46,501
area was hit by earthquakes in

1141
00:42:46,602 --> 00:42:50,572
the past. But Seeber has no

1142
00:42:50,606 --> 00:42:51,873
way of knowing if the faults

1143
00:42:51,941 --> 00:42:53,375
are still active and

1144
00:42:53,409 --> 00:42:58,180
dangerous.

1145
00:42:58,281 --> 00:43:00,115
If a large earthquake hit New

1146
00:43:00,183 --> 00:43:02,184
York today, the consequences

1147
00:43:02,285 --> 00:43:05,453
would be catastrophic.

1148
00:43:05,555 --> 00:43:06,598
>> A large proportion of New

1149
00:43:06,622 --> 00:43:07,889
York City buildings are simply

1150
00:43:07,924 --> 00:43:09,090
not built to withstand

1151
00:43:09,158 --> 00:43:10,792
earthquake shaking.

1152
00:43:10,827 --> 00:43:12,527
We worry about transportation

1153
00:43:12,562 --> 00:43:14,095
tunnels, in particular,

1154
00:43:14,163 --> 00:43:16,364
tunnels that traverse rivers

1155
00:43:16,465 --> 00:43:18,099
where parts of the tunnels are

1156
00:43:18,167 --> 00:43:19,634
rooted in solid rock and other

1157
00:43:19,702 --> 00:43:21,069
parts are resting on soft

1158
00:43:21,103 --> 00:43:22,737
sediment. The oscillation

1159
00:43:22,805 --> 00:43:23,471
of these two different

1160
00:43:23,539 --> 00:43:24,906
materials could cause severe

1161
00:43:25,007 --> 00:43:27,008
cracking and fracturing.

1162
00:43:27,109 --> 00:43:28,510
The infrastructure

1163
00:43:28,578 --> 00:43:30,478
would be severely damaged, it

1164
00:43:30,513 --> 00:43:32,047
would take tens of years to

1165
00:43:32,148 --> 00:43:33,582
repair the damage caused by

1166
00:43:33,616 --> 00:43:36,718
such a large event.

1167
00:43:36,752 --> 00:43:37,719
>> With the evidence

1168
00:43:37,753 --> 00:43:39,654
geologists have collected, the

1169
00:43:39,755 --> 00:43:41,289
story of the creation of New

1170
00:43:41,357 --> 00:43:44,860
York City can now be told.

1171
00:43:44,927 --> 00:43:46,761
The city's bedrock was formed

1172
00:43:46,829 --> 00:43:48,029
under a chain of mountains

1173
00:43:48,130 --> 00:43:51,266
over a mile high. Volcanoes

1174
00:43:51,300 --> 00:43:53,268
and lava fields over millions

1175
00:43:53,302 --> 00:43:55,470
of square miles split up the

1176
00:43:55,571 --> 00:43:57,172
ancient supercontinent and

1177
00:43:57,206 --> 00:43:58,807
created the east coast of

1178
00:43:58,841 --> 00:44:01,376
North America. Glacial ice,

1179
00:44:01,477 --> 00:44:02,677
four times as high as the

1180
00:44:02,745 --> 00:44:04,579
Empire State building, carved

1181
00:44:04,647 --> 00:44:06,915
out the deep Hudson River.

1182
00:44:06,949 --> 00:44:08,817
A catastrophic flash flood

1183
00:44:08,851 --> 00:44:10,085
broke through the moraine to

1184
00:44:10,119 --> 00:44:12,187
form the Narrows and opened up

1185
00:44:12,288 --> 00:44:13,855
New York City's harbor to the

1186
00:44:13,923 --> 00:44:15,824
oceans.

1187
00:44:20,029 --> 00:44:20,929
Looking ahead to the

1188
00:44:21,030 --> 00:44:23,164
distant future, geologists see

1189
00:44:23,199 --> 00:44:24,933
more challenging times for the

1190
00:44:25,001 --> 00:44:28,737
city. In 40,000 years,

1191
00:44:28,804 --> 00:44:29,915
they predict this region will

1192
00:44:29,939 --> 00:44:31,740
be engulfed by another ice

1193
00:44:31,807 --> 00:44:35,277
sheet. And in 250 million

1194
00:44:35,378 --> 00:44:37,379
years, the Atlantic will start

1195
00:44:37,480 --> 00:44:40,115
to shrink again. Europe and

1196
00:44:40,182 --> 00:44:42,117
Africa will eventually crash

1197
00:44:42,184 --> 00:44:44,619
back into the American coast.

1198
00:44:44,654 --> 00:44:46,254
The fossilized remains of the

1199
00:44:46,289 --> 00:44:47,722
once great city of New York

1200
00:44:47,757 --> 00:44:49,457
will become just another layer

1201
00:44:49,558 --> 00:44:51,726
of rock in a vast new mountain

1202
00:44:51,761 --> 00:44:54,829
range. A footnote in the

1203
00:44:54,897 --> 00:44:56,998
immense, ever-changing story

1204
00:44:57,033 --> 00:44:58,649
of planet earth.

1205
00:44:58,673 --> 00:45:05,573
== sync, corrected by elderman ==
@elder_man