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WWW.MY-SUBS.CO

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>> Earth--a unique planet--

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restless and dynamic.

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Continents shift and clash.

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Volcanoes erupt, glaciers grow

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and recede.

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Titanic forces that are

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constantly at work, leaving a

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trail of geological mysteries

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behind.

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This episode explores Everest,

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the highest mountain on planet

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Earth.

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In order to unlock its secrets,

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a daring mission is undertaken

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to bring back rocks from

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the summit.

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This journey of discovery into

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the formation of Everest will

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uncover ancient fossils,

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hidden crystals, epic weather,

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and immense structures etched

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into the mountains...All part

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of the incredible story of...

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S02x08 Everest
Original Air Date on January 19, 2009

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-- Sync, corrected by elderman --
-- for MY-SUBS.com ---

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The Himalayas stretch 1,500

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miles across Asia.

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They're home to 14 of the

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tallest mountains on the planet.

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And one rises above all

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others...

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Everest.

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At 5 1/2 miles tall, Everest is

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the highest mountain in the

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world.

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In order to figure out how

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this giant mountain was made,

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geologists need evidence--

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rock samples from Everest.

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It's a dangerous mission, and

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only a few people are willing

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to undertake it.

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Kenton Cool is one of the

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world's best high-altitude

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climbers, and he will embark on

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this geological mission to the

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summit of Everest.

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His instructions from geologists

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are to collect rock samples from

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3 places: One from the summit

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and two from lower down.

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These incredibly rare samples

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will give investigators

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crucial evidence.

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Kenton is at Everest base camp.

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Pitched on jagged rocks at

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17,500 feet, this camp is over

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3 miles above sea level.

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>> Sorting out the last of the

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items I need to take on our

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summit push, and I've just been

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to collect a load of ziploc

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bags, which I hope to put all

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the samples in.

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>> Over the next 5 days, he will

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climb 12,000 feet--the

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equivalent vertical height

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of 8 Empire State buildings.

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Kenton starts his mission from

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base camp.

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He negotiates the Khumbu

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Icefall, a frozen river with

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crevasses thousands of feet

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deep.

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It's a treacherous ascent, as

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all this glacial ice is

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constantly moving, and looming

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ice towers threaten to collapse.

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Kenton now has the most

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dangerous section ahead of him.

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At 21,000 feet, he is alread

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higher than Mount McKinley.

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He has a sheer ice climb up the

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side of Everest.

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[wind howling]

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Winds reach speeds in excess of

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100 miles an hour and

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temperatures drop

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to -40 degrees.

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Since leaving base camp, kenton

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Has climbed for 4 days.

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At 26,000 feet, he reaches the

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point which joins Everest and

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its neighboring mountain,

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Lhotse.

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>> So here we are. This is the

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south col, one of the highest

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camps in the world--7,950

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meters, so high that nothing can

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actually live here.

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>> From this camp, Kenton will

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leave at 3 a.m., climb through

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the night, and aim to arrive at

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the summit in the morning.

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>> It's pitch-black, about 3:00

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in the morning.

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>> Timing is crucial and the

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weather must be ideal.

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The window for ascent is narrow.

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There are only around 12 days of

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the year when climbers can make

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it to the summit.

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Kenton must take this

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opportunity.

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He now ventures into what

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climbers call the death zone.

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Oxygen is needed to make the

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climb, as the air is 3 times

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thinner than at sea level.

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One in 10 people die climbing

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Everest, and most fatalities

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occur during this final stage.

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>> [breathing heavily]

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One more.

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>> Kenton finally reaches the

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top of Everest.

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>> 8,850 meters.

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We are the highest people in

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the world.

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>> This is the view from the

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highest place on planet earth.

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For most climbers, the summit is

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the ultimate goal...

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but for Kenton, his mission has

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only just begun.

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He heads just below the summit

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to find an exposed outcrop

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of rock.

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Kenton's first sample is a gray

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limestone.

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It's soft and easy to break off.

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This is a sample of the highest

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rock in the world.

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One down, two to go.

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Kenton descends further to

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collect the next sample.

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Just below the summit, the rock

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changes.

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Climbers call it the "yellow

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band" due to its distinctive

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color.

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The rock is dramatically

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different from the summit--

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much harder and yellow in

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color.

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This is a layer of marble.

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>> [grunts]

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All right, there we go.

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There's a lot of the yellow

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band.

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Right, so that's that.

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That's the yellow band.

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We've collected samples from

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here.

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It's not been very easy.

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We're getting out of here.

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It's beginning to snow.

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>> But he has one more to go.

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Kenton starts the long descent

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to where he'll get the next

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piece of evidence.

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He enters into the Western Cwm,

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a huge, u-shaped valley which

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has been carved by the Khumbu

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Glacier--a frozen river of ice

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that has relentlessly pushed

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downward over the past million

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years.

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Rock and debris in the glacier

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have ground away at the rock

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underneath,

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Revealing the base of Everest.

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Kenton needs to take his final

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sample from this area of

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distinctive white rock--

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granite.

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>> So here we are in

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the Western Cwm on Everest,

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about 6,400 meters.

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I'm actually stood underneath

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one of the easier outcrops to

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get to.

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This is a big sort of granite

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cliff above me.

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>> This white rock is full of

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crystals.

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It's extremely hard and

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different again from the summit

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limestone and the marble.

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>> Yeah, we have quite a nice

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sample of the granite there.

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>> With the 3 precious samples

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safely packed away, Kenton takes

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them to the University of

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Oxford.

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Here they will be analyzed by

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the world's leading authority on

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Everest, Mike Searle.

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>> So, Mike, this is your

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summit rock.

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Now, that is from the top

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of the world.

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>> Well, this sample, Kenton,

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is probably one of the most

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important samples of the whole

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Expedition, so it's literally

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worth its weight in gold

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geologically.

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This came from the summit of

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Everest, right there.

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The next rock down that you

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collected was from the yellow

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band.

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And even further down is

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another rock, a granite.

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>> Almost a complete picture

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of Everest.

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>> That's right, yes.

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>> Fantastic.

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>> These 3 rocks are the major

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components which make up

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Everest.

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>> All that effort to get up to

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the summit was, I can tell you,

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was absolutely worth it to get

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the sample.

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>> Good, good. I hope so.

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>> For the next step is we want

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to find out what's in it.

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>> The summit rock is cut into

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a thin section...

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so thin, light can pass

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through it.

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>> Ok, let's have a look at this

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slide of the limestone that's

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from the summit of Everest.

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>> The highest rock sample in

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the world reveals its secret.

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>> That looks interesting.

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What's that?

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We've got a section here

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through a crinoid stem.

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Crinoid is a sea lily.

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>> From fossil records, the

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section can be dated.

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It is over 400 million years

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old.

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The sea lily is evidence that

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the summit rock of Everest was

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formed in an ancient marine

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environment.

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>> So, from seeing this

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evidence, we can categorically

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say that this rock would have

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started life at the bottom of

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the sea floor, and then I've

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collected it from the very, very

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top of the world, from the

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summit of Everest itself.

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That's just amazing.

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>> But a mystery is revealed:

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How had rock with marine fossils

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in it ended up on the top

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of Everest?

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The mission to collect rock

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samples from Everest has

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uncovered two clues as to how

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it formed.

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Samples show that the mountain

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is made from 3 distinctive

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types of rock.

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Rock from the summit of Everest

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contains marine fossils, proving

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it started life on the bottom

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of the sea.

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To figure out how sea floor

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came to be on top of the

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highest mountain in the world,

289
00:11:06,495 --> 00:11:08,096
geologists need to find

290
00:11:08,130 --> 00:11:09,764
evidence that is millions of

291
00:11:09,832 --> 00:11:13,668
years old, going back way

292
00:11:13,769 --> 00:11:15,737
before the Himalayas were even

293
00:11:15,771 --> 00:11:18,206
formed.

294
00:11:20,267 --> 00:11:22,735
>> 400 million years ago, no

295
00:11:22,770 --> 00:11:26,105
trace of the Himalayas existed.

296
00:11:26,173 --> 00:11:28,674
The sea lily,  now fossilized on

297
00:11:28,709 --> 00:11:30,710
the summit of Everest, is proof

298
00:11:30,778 --> 00:11:32,712
that there was once water where

299
00:11:32,780 --> 00:11:37,884
now this great mountain stands.

300
00:11:37,985 --> 00:11:39,585
But to figure out whether this

301
00:11:39,620 --> 00:11:41,888
was just a shallow inland sea

302
00:11:41,989 --> 00:11:45,358
or a great ocean, geologist

303
00:11:45,425 --> 00:11:47,326
Mike Searle travels to the

304
00:11:47,427 --> 00:11:49,529
Himalayas.

305
00:11:49,596 --> 00:11:52,064
He begins the investigation at

306
00:11:52,166 --> 00:11:54,567
the Ghar Khola river.

307
00:11:54,601 --> 00:11:55,868
It flows down from the high

308
00:11:55,969 --> 00:11:57,870
Himalayas and carries with it

309
00:11:57,938 --> 00:12:00,573
an intriguing clue.

310
00:12:00,641 --> 00:12:01,841
>> The rock I've got in my hand

311
00:12:01,909 --> 00:12:03,576
at the moment may look a bit

312
00:12:03,644 --> 00:12:05,278
boring and insignificant.

313
00:12:05,379 --> 00:12:07,079
It's just a pebble taken from

314
00:12:07,114 --> 00:12:09,582
the river, but it's actually

315
00:12:09,650 --> 00:12:12,185
a key clue as to the formation

316
00:12:12,219 --> 00:12:13,653
of the Himalayas and the

317
00:12:13,754 --> 00:12:15,388
evolution of the rocks.

318
00:12:15,489 --> 00:12:17,824
It's almost by magic that when

319
00:12:17,858 --> 00:12:19,826
you smash a rock like this open,

320
00:12:19,860 --> 00:12:22,495
what it reveals inside is an

321
00:12:22,563 --> 00:12:24,630
absolutely beautiful fossil, and

322
00:12:24,665 --> 00:12:26,299
this fossil is what we call an

323
00:12:26,400 --> 00:12:29,735
Ammonite.

324
00:12:29,770 --> 00:12:31,804
>> This ancient creature is part

325
00:12:31,905 --> 00:12:33,806
of the squid family.

326
00:12:33,907 --> 00:12:35,541
It's proof of a complex

327
00:12:35,642 --> 00:12:39,378
ecosystem found in a deep ocean.

328
00:12:39,446 --> 00:12:41,147
>> A giant squid swimming around

329
00:12:41,181 --> 00:12:43,549
in the seas that once lay

330
00:12:43,617 --> 00:12:45,618
between India and Asia, and this

331
00:12:45,652 --> 00:12:46,886
is some of the key evidence

332
00:12:46,920 --> 00:12:48,187
that we've got that there was

333
00:12:48,288 --> 00:12:49,655
a major ocean between the

334
00:12:49,723 --> 00:12:52,091
continents.

335
00:12:52,159 --> 00:12:53,726
>> But to find marine fossils

336
00:12:53,794 --> 00:12:56,028
in the high Himalayas and on

337
00:12:56,096 --> 00:12:57,997
the summit of Everest, some

338
00:12:58,031 --> 00:13:00,099
immense geological force must

339
00:13:00,167 --> 00:13:01,467
have pushed the ocean floor

340
00:13:01,568 --> 00:13:04,537
upwards above the water.

341
00:13:04,571 --> 00:13:06,439
Figuring out how this happened

342
00:13:06,473 --> 00:13:07,840
has taken geologists over

343
00:13:07,908 --> 00:13:09,942
a hundred years.

344
00:13:10,010 --> 00:13:11,310
The first lead in this

345
00:13:11,378 --> 00:13:12,745
investigation came from an

346
00:13:12,813 --> 00:13:14,580
unlikely place...

347
00:13:14,648 --> 00:13:18,184
Antarctica.

348
00:13:18,218 --> 00:13:20,920
In 1910, the renowned Antarctic

349
00:13:20,988 --> 00:13:23,923
explorer Robert Scott began his

350
00:13:24,024 --> 00:13:26,025
ill-fated expedition to the

351
00:13:26,093 --> 00:13:28,094
South Pole.

352
00:13:28,128 --> 00:13:29,929
After reaching the pole, Scott

353
00:13:30,030 --> 00:13:34,367
and 5 of his team died.

354
00:13:34,401 --> 00:13:36,469
When the bodies were discovered,

355
00:13:36,503 --> 00:13:37,904
among their equipment were

356
00:13:38,005 --> 00:13:39,305
carefully wrapped and labeled

357
00:13:39,406 --> 00:13:42,408
fossils.

358
00:13:42,476 --> 00:13:44,777
The fossils were part of an

359
00:13:44,845 --> 00:13:46,479
ancient plant called

360
00:13:46,513 --> 00:13:50,583
Glossopteris, and specimens are

361
00:13:50,684 --> 00:13:52,385
preserved at the British

362
00:13:52,419 --> 00:13:54,687
Antarctic survey.

363
00:13:54,788 --> 00:13:55,688
>> Glossopteris is a type of

364
00:13:55,756 --> 00:13:57,223
plant known as seed fern.

365
00:13:57,291 --> 00:13:58,591
And from many different lines

366
00:13:58,692 --> 00:14:00,059
of evidence, such as roots and

367
00:14:00,127 --> 00:14:02,762
leaves and preserved trunks,

368
00:14:02,863 --> 00:14:04,230
Paleontologists think that

369
00:14:04,298 --> 00:14:06,132
Glossopteris was actually a type

370
00:14:06,233 --> 00:14:08,768
of tree.

371
00:14:08,869 --> 00:14:11,037
>> Soon this humble tree fossil

372
00:14:11,104 --> 00:14:14,440
was found across the globe...

373
00:14:14,474 --> 00:14:20,646
in India, South America, Africa,

374
00:14:20,747 --> 00:14:26,018
Madagascar, and Australia.

375
00:14:26,119 --> 00:14:28,487
Geologists now had a puzzle:

376
00:14:28,555 --> 00:14:30,489
How had this one species of

377
00:14:30,590 --> 00:14:32,825
plant spread between continents

378
00:14:32,859 --> 00:14:35,227
separated by thousands of miles

379
00:14:35,295 --> 00:14:36,829
of ocean?

380
00:14:36,863 --> 00:14:37,863
>> Glossopteris is a very

381
00:14:37,931 --> 00:14:38,931
important fossil because it

382
00:14:38,999 --> 00:14:40,566
could not have dispersed over

383
00:14:40,667 --> 00:14:41,600
vast distances.

384
00:14:41,668 --> 00:14:42,768
It couldn't have just been

385
00:14:42,869 --> 00:14:44,003
dispersed by the wind or by

386
00:14:44,037 --> 00:14:46,038
birds across oceans.

387
00:14:46,139 --> 00:14:47,773
>> If Glossopteris couldn't

388
00:14:47,874 --> 00:14:50,209
cross oceans, then scientists

389
00:14:50,310 --> 00:14:53,045
were left with one conclusion:

390
00:14:53,146 --> 00:14:55,781
When these trees were alive

391
00:14:55,849 --> 00:14:59,085
250 million years ago, the

392
00:14:59,152 --> 00:15:01,087
continents were all joined

393
00:15:01,154 --> 00:15:02,888
together.

394
00:15:02,990 --> 00:15:03,956
They were part of a

395
00:15:03,991 --> 00:15:05,725
Supercontinent geologists call

396
00:15:05,792 --> 00:15:07,693
Gondwanaland.

397
00:15:07,728 --> 00:15:09,428
Glossopteris was able to spread

398
00:15:09,496 --> 00:15:14,066
across this ancient landmass.

399
00:15:14,167 --> 00:15:17,636
But then Gondwana was split up

400
00:15:17,704 --> 00:15:20,072
by violent tectonic forces,

401
00:15:20,140 --> 00:15:21,540
Which pushed the continents

402
00:15:21,641 --> 00:15:24,643
apart, and 80 million years ago,

403
00:15:24,711 --> 00:15:26,912
India broke away from the

404
00:15:26,980 --> 00:15:28,781
Supercontinent.

405
00:15:28,815 --> 00:15:30,282
It traveled north and

406
00:15:30,350 --> 00:15:35,187
eventually smashed into Asia.

407
00:15:35,288 --> 00:15:37,089
To get the full picture,

408
00:15:37,157 --> 00:15:38,924
geologists now knew they must

409
00:15:38,992 --> 00:15:40,292
get an exact date for this

410
00:15:40,360 --> 00:15:41,627
collision.

411
00:15:41,695 --> 00:15:43,195
Once again, they turned to

412
00:15:43,263 --> 00:15:45,264
marine fossils.

413
00:15:45,365 --> 00:15:47,199
>> We know the age of collision

414
00:15:47,267 --> 00:15:50,069
of India and Asia from several

415
00:15:50,103 --> 00:15:51,637
factors, but the most important

416
00:15:51,738 --> 00:15:54,206
one is the age of the youngest

417
00:15:54,274 --> 00:15:56,642
marine fossils that are

418
00:15:56,743 --> 00:15:58,911
preserved along that collision

419
00:15:59,012 --> 00:16:00,279
belt.

420
00:16:00,380 --> 00:16:01,981
And the age of those fossils is

421
00:16:02,015 --> 00:16:03,382
very precisely dated--

422
00:16:03,483 --> 00:16:06,619
50.5 million years.

423
00:16:06,653 --> 00:16:09,021
>> 80 million years ago, India

424
00:16:09,089 --> 00:16:10,656
left Gondwana.

425
00:16:10,724 --> 00:16:13,459
50.5 million years ago,

426
00:16:13,493 --> 00:16:16,362
it hit Asia.

427
00:16:16,396 --> 00:16:18,764
India traveled 4,000 miles in

428
00:16:18,832 --> 00:16:22,568
just 30 million years, very fast

429
00:16:22,636 --> 00:16:25,037
in geological time.

430
00:16:25,105 --> 00:16:27,473
>> India was drifting northwards

431
00:16:27,541 --> 00:16:29,308
across the Indian Ocean at very

432
00:16:29,409 --> 00:16:31,944
rapid plate tectonic speeds,

433
00:16:32,012 --> 00:16:33,813
and we're talking here between

434
00:16:33,847 --> 00:16:36,282
10 and 12 inches per year,

435
00:16:36,316 --> 00:16:38,551
which is very rapid.

436
00:16:38,585 --> 00:16:40,052
>> It's this speed that goes

437
00:16:40,120 --> 00:16:41,921
some way to explain the unique

438
00:16:41,955 --> 00:16:43,856
size of the Himalayas,

439
00:16:43,957 --> 00:16:47,126
Because, as with any smash,

440
00:16:47,227 --> 00:16:48,961
the faster the collision,

441
00:16:49,029 --> 00:16:52,298
the bigger the wreck.

442
00:16:52,399 --> 00:16:54,600
The investigation has now

443
00:16:54,668 --> 00:16:56,735
uncovered clues to prove India

444
00:16:56,770 --> 00:16:59,238
and Asia were once separate.

445
00:16:59,306 --> 00:17:02,041
Ammonites are evidence that

446
00:17:02,142 --> 00:17:04,043
an ocean once existed between

447
00:17:04,111 --> 00:17:06,245
India and Asia.

448
00:17:06,313 --> 00:17:08,581
Glossopteris fossils prove that

449
00:17:08,615 --> 00:17:10,049
India was once part of a

450
00:17:10,117 --> 00:17:11,417
Supercontinent called

451
00:17:11,485 --> 00:17:14,687
Gondwanaland.

452
00:17:14,788 --> 00:17:16,222
>> The next part of the

453
00:17:16,256 --> 00:17:17,690
investigation is to discover

454
00:17:17,757 --> 00:17:20,326
how this intercontinental smash

455
00:17:20,427 --> 00:17:22,661
gave rise to the tallest

456
00:17:22,696 --> 00:17:24,598
mountain in the world.

457
00:17:30,682 --> 00:17:32,316
>> Geologists piecing together

458
00:17:32,384 --> 00:17:33,784
the story of how Everest was

459
00:17:33,852 --> 00:17:37,221
made have shown that 400 million

460
00:17:37,322 --> 00:17:40,224
years ago, a wide ocean existed

461
00:17:40,325 --> 00:17:44,228
where the Himalayas now stand.

462
00:17:44,295 --> 00:17:47,598
India was part of Gondwanaland

463
00:17:47,699 --> 00:17:50,134
until 80 million years ago, when

464
00:17:50,235 --> 00:17:52,069
violent tectonic forces threw

465
00:17:52,137 --> 00:17:53,871
the planet into turmoil and

466
00:17:53,938 --> 00:17:55,706
split up this ancient landmass,

467
00:17:55,774 --> 00:17:59,710
pushing India northwards.

468
00:17:59,778 --> 00:18:02,045
50 million years ago, India

469
00:18:02,147 --> 00:18:05,215
collided with Asia, and for the

470
00:18:05,250 --> 00:18:07,317
next 30 million years, this

471
00:18:07,419 --> 00:18:09,686
intercontinental smash began to

472
00:18:09,754 --> 00:18:11,588
shape the world's highest

473
00:18:11,623 --> 00:18:14,057
mountains.

474
00:18:16,528 --> 00:18:18,262
Traces of the first stage in

475
00:18:18,329 --> 00:18:19,963
this process can still be seen

476
00:18:20,064 --> 00:18:22,766
in the Himalayas today.

477
00:18:22,801 --> 00:18:24,701
The best way to spot them is

478
00:18:24,769 --> 00:18:26,403
from the air.

479
00:18:26,438 --> 00:18:27,871
>> Because the high Himalayas

480
00:18:27,906 --> 00:18:30,073
are so incredibly inaccessible--

481
00:18:30,141 --> 00:18:31,341
I mean, just look at that view

482
00:18:31,409 --> 00:18:33,076
out there--there's a sea of

483
00:18:33,178 --> 00:18:33,877
mountains.

484
00:18:33,912 --> 00:18:35,679
All of them are over 20,000

485
00:18:35,713 --> 00:18:36,547
feet.

486
00:18:36,614 --> 00:18:37,714
There must be hundreds of them,

487
00:18:37,816 --> 00:18:39,249
and those are impossible

488
00:18:39,317 --> 00:18:40,884
mountains for a mere mortal

489
00:18:40,952 --> 00:18:42,886
to climb.

490
00:18:42,987 --> 00:18:45,556
>> This is geology on a massive

491
00:18:45,623 --> 00:18:47,458
scale.

492
00:18:47,525 --> 00:18:49,159
The distinctive formations come

493
00:18:49,194 --> 00:18:51,528
into view.

494
00:18:51,629 --> 00:18:55,966
Huge folds of rock, clearly seen

495
00:18:56,000 --> 00:18:58,001
on the sides of the mountains.

496
00:18:58,069 --> 00:18:59,169
>> All of these folds that

497
00:18:59,237 --> 00:19:00,471
we're seeing right here on

498
00:19:00,538 --> 00:19:02,272
Dhaulagiri and Tukuche peak

499
00:19:02,340 --> 00:19:03,540
were formed during the first

500
00:19:03,608 --> 00:19:04,808
part of the Himalayan

501
00:19:04,909 --> 00:19:06,810
mountain-building process,

502
00:19:06,878 --> 00:19:08,111
so when India first collided

503
00:19:08,179 --> 00:19:10,080
with Asia, the first thing to

504
00:19:10,114 --> 00:19:11,748
happen was the northern margin

505
00:19:11,816 --> 00:19:13,884
of India started buckling and

506
00:19:13,918 --> 00:19:15,819
folding, and those folds are

507
00:19:15,920 --> 00:19:17,621
just so spectacular.

508
00:19:17,655 --> 00:19:18,522
When you look out the window

509
00:19:18,556 --> 00:19:20,290
here, they're just unbelievably

510
00:19:20,391 --> 00:19:22,893
impressive.

511
00:19:25,663 --> 00:19:27,664
>> Like a giant train wreck,

512
00:19:27,732 --> 00:19:30,667
India collided with Asia.

513
00:19:30,735 --> 00:19:32,469
The land and ocean floor that

514
00:19:32,570 --> 00:19:34,638
lay between literally folded up

515
00:19:34,672 --> 00:19:37,641
under the enormous pressure.

516
00:19:37,675 --> 00:19:39,676
But folds are only part of the

517
00:19:39,744 --> 00:19:41,578
story.

518
00:19:41,646 --> 00:19:42,946
Alone, they don't explain the

519
00:19:43,014 --> 00:19:45,749
Himalayas' vast size.

520
00:19:48,453 --> 00:19:49,953
Back on the trail, Searle is on

521
00:19:50,021 --> 00:19:52,189
the hunt for further clues.

522
00:19:52,223 --> 00:19:54,024
>> This is what makes the whole

523
00:19:54,092 --> 00:19:55,926
trip really worthwhile.

524
00:19:56,027 --> 00:19:58,862
We've just spent 5 days hiking

525
00:19:58,930 --> 00:20:00,864
up through the jungle, through

526
00:20:00,932 --> 00:20:03,233
the forest, pouring with rain.

527
00:20:03,301 --> 00:20:05,302
And up there, finally, are the

528
00:20:05,403 --> 00:20:07,404
high Himalayas.

529
00:20:07,505 --> 00:20:12,309
I just love those mountains.

530
00:20:12,377 --> 00:20:14,478
look at those peaks up there.

531
00:20:14,512 --> 00:20:18,782
They are absolutely beautiful.

532
00:20:18,850 --> 00:20:20,784
>> Searle points to an

533
00:20:20,852 --> 00:20:22,953
intriguing, giant scar which is

534
00:20:23,021 --> 00:20:24,688
revealed on the face of one of

535
00:20:24,756 --> 00:20:26,323
the mountains.

536
00:20:26,391 --> 00:20:28,125
It's evidence of the next

537
00:20:28,192 --> 00:20:29,993
dramatic phase in the building

538
00:20:30,028 --> 00:20:32,563
of the Himalayas.

539
00:20:32,664 --> 00:20:34,464
>> This is a sketch of what we

540
00:20:34,566 --> 00:20:36,300
are actually seeing in front of

541
00:20:36,401 --> 00:20:38,168
us, with the big mountain of

542
00:20:38,202 --> 00:20:40,671
Dhaulagiri here and the big

543
00:20:40,738 --> 00:20:42,940
folds on the peak of Tukuche to

544
00:20:43,041 --> 00:20:45,742
the right, with this enormous,

545
00:20:45,810 --> 00:20:47,311
great fault that is

546
00:20:47,378 --> 00:20:49,046
magnificently exposed, right

547
00:20:49,113 --> 00:20:51,214
along the base of Dhaulagiri,

548
00:20:51,316 --> 00:20:53,116
coming right down to the Kali

549
00:20:53,184 --> 00:20:54,952
Gandaki river valley at the

550
00:20:55,019 --> 00:20:56,820
bottom.

551
00:20:56,854 --> 00:20:58,589
>> The fault is a fracture

552
00:20:58,656 --> 00:21:00,090
running right through the

553
00:21:00,124 --> 00:21:01,224
mountains.

554
00:21:01,292 --> 00:21:02,392
>> Well, the first step into

555
00:21:02,460 --> 00:21:04,661
forming the Himalayas is that

556
00:21:04,729 --> 00:21:06,496
the rocks are folded into giant

557
00:21:06,598 --> 00:21:07,931
folds.

558
00:21:08,032 --> 00:21:09,566
And when that process continues,

559
00:21:09,601 --> 00:21:11,401
the rock can no longer fold, so

560
00:21:11,469 --> 00:21:14,137
they become overturned folds.

561
00:21:14,205 --> 00:21:15,572
And when that process continues

562
00:21:15,607 --> 00:21:17,741
even further, that overturned

563
00:21:17,775 --> 00:21:20,143
fold actually moves along

564
00:21:20,211 --> 00:21:22,646
a very discrete fault plane,

565
00:21:22,680 --> 00:21:24,147
and that's exactly what we see

566
00:21:24,215 --> 00:21:26,883
throughout the whole Himalayas.

567
00:21:26,951 --> 00:21:30,587
So rocks are formed by folding

568
00:21:30,688 --> 00:21:33,590
and thrusting.

569
00:21:33,691 --> 00:21:35,225
>> Rocks can only be bent

570
00:21:35,326 --> 00:21:36,860
so far.

571
00:21:36,928 --> 00:21:38,795
Once rock has been bent beyond

572
00:21:38,863 --> 00:21:41,331
its limits, it breaks and causes

573
00:21:41,399 --> 00:21:43,333
a fault.

574
00:21:43,434 --> 00:21:45,702
The process of faulting puts

575
00:21:45,770 --> 00:21:47,871
different rock types one on top

576
00:21:47,939 --> 00:21:50,340
of the other.

577
00:21:50,441 --> 00:21:53,443
>> Faults are juxtaposed rocks

578
00:21:53,511 --> 00:21:55,078
of two different types.

579
00:21:55,146 --> 00:21:57,714
So the big, huge fault that cuts

580
00:21:57,782 --> 00:21:58,882
through the tops of the

581
00:21:58,983 --> 00:22:00,317
high Himalayas, the top of

582
00:22:00,351 --> 00:22:01,885
Everest, are rocks that are

583
00:22:01,986 --> 00:22:07,858
putting limestones over marble.

584
00:22:07,892 --> 00:22:10,060
>> This is exactly what was

585
00:22:10,161 --> 00:22:11,895
revealed by Kenton's rock

586
00:22:11,996 --> 00:22:14,164
samples from Everest--

587
00:22:14,265 --> 00:22:16,767
limestones at the summit lying

588
00:22:16,801 --> 00:22:18,869
on top of the hard marble of

589
00:22:18,936 --> 00:22:21,605
the yellow band...

590
00:22:21,673 --> 00:22:23,774
Evidence that the top of Everest

591
00:22:23,875 --> 00:22:25,876
was initially created by folding

592
00:22:25,943 --> 00:22:28,045
and faulting.

593
00:22:28,112 --> 00:22:29,680
But this only explains part of

594
00:22:29,747 --> 00:22:31,248
the story.

595
00:22:31,315 --> 00:22:32,783
To create a mountain the size

596
00:22:32,850 --> 00:22:34,785
of Everest, geologists knew

597
00:22:34,852 --> 00:22:35,986
that there must have been

598
00:22:36,054 --> 00:22:37,688
another, more powerful

599
00:22:37,755 --> 00:22:39,156
mountain-building process

600
00:22:39,223 --> 00:22:41,558
at work.

601
00:22:41,626 --> 00:22:44,027
Clues to exactly what this

602
00:22:44,128 --> 00:22:47,831
process was can be found in the

603
00:22:47,899 --> 00:22:51,034
Ghalemdi Khola River.

604
00:22:51,135 --> 00:22:54,204
>> This river is a giant

605
00:22:54,272 --> 00:22:56,106
garbage chute, bringing all

606
00:22:56,207 --> 00:22:57,841
these boulders eroded off the

607
00:22:57,942 --> 00:22:59,843
high Himalayas to the north and

608
00:22:59,911 --> 00:23:01,945
sweeping them down in great

609
00:23:02,046 --> 00:23:03,580
floods, down to the plains of

610
00:23:03,681 --> 00:23:05,315
India to the south.

611
00:23:05,349 --> 00:23:06,917
So this was a great place to

612
00:23:06,951 --> 00:23:09,052
come to sample all the rocks

613
00:23:09,120 --> 00:23:11,054
that make up the high mountains

614
00:23:11,122 --> 00:23:12,589
to the north.

615
00:23:12,657 --> 00:23:14,324
>> As any detective knows, some

616
00:23:14,392 --> 00:23:15,859
of the best finds are made by

617
00:23:15,927 --> 00:23:17,861
sifting through garbage.

618
00:23:17,962 --> 00:23:19,596
This time it's garbage from the

619
00:23:19,664 --> 00:23:21,398
Himalayan peaks.

620
00:23:21,466 --> 00:23:24,234
>> This is exactly the rock I've

621
00:23:24,302 --> 00:23:25,669
been looking for.

622
00:23:25,737 --> 00:23:27,671
This is a beautiful example of

623
00:23:27,705 --> 00:23:30,974
a Kyanite Gneiss, which is

624
00:23:31,042 --> 00:23:33,844
composed of these beautiful,

625
00:23:33,878 --> 00:23:37,681
blue-bladed crystals of Kyanite.

626
00:23:37,782 --> 00:23:40,951
>> Kyanite is a gemstone, and

627
00:23:41,018 --> 00:23:42,586
it gives a clue as to how these

628
00:23:42,687 --> 00:23:44,421
rocks formed.

629
00:23:44,522 --> 00:23:46,389
>> This mineral is very specific

630
00:23:46,424 --> 00:23:48,759
to a geologist, and it tells us

631
00:23:48,793 --> 00:23:51,528
that this rock has been buried

632
00:23:51,596 --> 00:23:54,064
to depths of about 30 miles or

633
00:23:54,165 --> 00:23:56,600
more, under high temperature

634
00:23:56,667 --> 00:23:59,536
and high pressure.

635
00:23:59,604 --> 00:24:01,338
>> Rock was not only pushed

636
00:24:01,439 --> 00:24:03,073
upwards by the collision, but

637
00:24:03,174 --> 00:24:05,075
also down towards the earth's

638
00:24:05,143 --> 00:24:07,244
molten core.

639
00:24:07,311 --> 00:24:08,979
Heat and pressure changed the

640
00:24:09,080 --> 00:24:10,714
rock and formed Kyanite

641
00:24:10,782 --> 00:24:12,816
crystals.

642
00:24:12,884 --> 00:24:14,417
Another boulder in the river

643
00:24:14,452 --> 00:24:16,319
gives a further clue as to what

644
00:24:16,354 --> 00:24:18,155
was going on at these great

645
00:24:18,222 --> 00:24:19,890
depths.

646
00:24:19,957 --> 00:24:21,057
>> This white rock is

647
00:24:21,092 --> 00:24:22,793
a himalayan granite.

648
00:24:22,860 --> 00:24:24,161
Most of the highest peaks of the

649
00:24:24,228 --> 00:24:25,729
Himalayas are actually formed

650
00:24:25,797 --> 00:24:27,063
of this rock.

651
00:24:27,098 --> 00:24:28,532
And, of course, the base of

652
00:24:28,599 --> 00:24:29,800
Everest is formed of exactly

653
00:24:29,901 --> 00:24:31,535
the same.

654
00:24:31,602 --> 00:24:32,969
The presence of these white

655
00:24:33,004 --> 00:24:35,972
streaks tell me that this rock

656
00:24:36,007 --> 00:24:38,074
was actually partially molten,

657
00:24:38,142 --> 00:24:39,876
at the highest temperatures,

658
00:24:39,911 --> 00:24:40,911
During the Himalayan

659
00:24:41,012 --> 00:24:43,513
mountain-building process.

660
00:24:43,548 --> 00:24:45,282
>> The rock was pushed so far

661
00:24:45,349 --> 00:24:47,017
beneath the earth's surface that

662
00:24:47,084 --> 00:24:48,819
it reached heat in excess of

663
00:24:48,920 --> 00:24:51,087
4,000 degrees fahrenheit and

664
00:24:51,189 --> 00:24:53,657
began to melt.

665
00:24:53,724 --> 00:24:55,826
Once it was molten, it was able

666
00:24:55,927 --> 00:24:58,428
to move and flow.

667
00:24:58,462 --> 00:25:00,363
>> Well, you can think of the

668
00:25:00,431 --> 00:25:01,798
Himalayas more as a conveyor

669
00:25:01,833 --> 00:25:04,434
belt system taking Indian plate

670
00:25:04,468 --> 00:25:06,636
rocks, pushing them down deep

671
00:25:06,737 --> 00:25:08,104
in the crust.

672
00:25:08,206 --> 00:25:10,473
They are altered by heating and

673
00:25:10,575 --> 00:25:13,210
increasing pressure, eventually

674
00:25:13,277 --> 00:25:15,645
melting to produce granite and

675
00:25:15,746 --> 00:25:17,848
then forced back up to the

676
00:25:17,915 --> 00:25:20,383
surface along these giant

677
00:25:20,484 --> 00:25:22,752
sheer planes.

678
00:25:22,820 --> 00:25:25,288
>> 20 million years ago, this

679
00:25:25,356 --> 00:25:27,290
amazing conveyor belt system

680
00:25:27,358 --> 00:25:29,125
was at work.

681
00:25:29,193 --> 00:25:31,394
As India pushed northwards,

682
00:25:31,462 --> 00:25:33,563
a liquid band of buoyant rock

683
00:25:33,664 --> 00:25:35,365
was forced towards the surface

684
00:25:35,399 --> 00:25:37,767
and cooled, forming a solid

685
00:25:37,835 --> 00:25:41,104
layer of granite--a process

686
00:25:41,138 --> 00:25:43,306
called "channel flow."

687
00:25:43,407 --> 00:25:45,642
>> Granites are very buoyant

688
00:25:45,676 --> 00:25:46,943
rocks, so when they're formed

689
00:25:47,044 --> 00:25:49,179
by partial melting of the crust,

690
00:25:49,213 --> 00:25:51,047
normally they're pushed up

691
00:25:51,115 --> 00:25:53,116
through the crust to form

692
00:25:53,217 --> 00:25:54,584
mountain ranges like you see in

693
00:25:54,685 --> 00:25:56,686
the Sierra Nevada or Yosemite

694
00:25:56,754 --> 00:25:58,822
National Park, for example.

695
00:25:58,856 --> 00:26:01,224
The Himalayas are different.

696
00:26:01,325 --> 00:26:03,693
These granites are flowing

697
00:26:03,761 --> 00:26:05,962
almost horizontally from where

698
00:26:06,030 --> 00:26:07,497
they formed--the southern part

699
00:26:07,598 --> 00:26:10,100
of the Tibetan Plateau--to form

700
00:26:10,134 --> 00:26:11,701
the high peaks of the Himalayas.

701
00:26:11,769 --> 00:26:12,869
And it's this conveyor belt

702
00:26:12,970 --> 00:26:14,871
system that keeps the high

703
00:26:14,939 --> 00:26:17,040
Himalayas actively up lifting

704
00:26:17,108 --> 00:26:20,410
to this day.

705
00:26:20,478 --> 00:26:22,112
>> The mountains were repeatedly

706
00:26:22,146 --> 00:26:25,515
jacked up to epic proportions.

707
00:26:25,583 --> 00:26:28,785
It's this unique process which

708
00:26:28,886 --> 00:26:30,053
accounts for the Himalayas'

709
00:26:30,154 --> 00:26:33,156
immense size.

710
00:26:33,257 --> 00:26:36,026
Kenton Cool's mission to Everest

711
00:26:36,060 --> 00:26:38,061
uncovered an unusually thick

712
00:26:38,162 --> 00:26:40,530
band of granite...

713
00:26:40,598 --> 00:26:43,800
proof that Everest's awesome

714
00:26:43,868 --> 00:26:46,169
size is due to the process of

715
00:26:46,237 --> 00:26:49,339
channel flow.

716
00:26:49,440 --> 00:26:52,242
Geologists investigating how

717
00:26:52,310 --> 00:26:53,610
Everest was built have

718
00:26:53,711 --> 00:26:56,513
discovered folds and faults,

719
00:26:56,614 --> 00:26:57,981
proof of the initial

720
00:26:58,082 --> 00:27:00,417
mountain-building process.

721
00:27:00,451 --> 00:27:02,953
White stripes of granite

722
00:27:02,987 --> 00:27:04,587
indicate the rock was melted at

723
00:27:04,622 --> 00:27:07,524
over 4,000 degrees, forming a

724
00:27:07,591 --> 00:27:08,892
giant conveyor belt of

725
00:27:08,993 --> 00:27:13,430
mountain-building power.

726
00:27:13,464 --> 00:27:15,732
But the Himalayas were set to

727
00:27:15,800 --> 00:27:17,534
become part of a geological

728
00:27:17,601 --> 00:27:19,970
battle between catastrophic

729
00:27:20,004 --> 00:27:23,640
forces and powers which would

730
00:27:23,708 --> 00:27:25,375
challenge the very height of

731
00:27:25,443 --> 00:27:27,145
Everest.

732
00:27:30,741 --> 00:27:33,075
>> 400 million years ago, the

733
00:27:33,110 --> 00:27:35,111
Himalayas started out life at

734
00:27:35,178 --> 00:27:38,180
the bottom of an immense ocean.

735
00:27:38,281 --> 00:27:40,483
50 million years ago, they were

736
00:27:40,550 --> 00:27:43,486
thrust into the skies as India

737
00:27:43,553 --> 00:27:47,123
smashed into the Asian landmass.

738
00:27:47,190 --> 00:27:49,525
Since that time, tectonic

739
00:27:49,559 --> 00:27:51,293
forces have created the tallest

740
00:27:51,394 --> 00:27:54,296
mountain in the world.

741
00:27:54,397 --> 00:27:55,664
But what of the immediate

742
00:27:55,766 --> 00:27:57,666
future?

743
00:27:57,734 --> 00:28:00,569
Will Everest continue to rise

744
00:28:00,670 --> 00:28:03,038
or will this giant soon be cut

745
00:28:03,106 --> 00:28:05,407
down?

746
00:28:05,475 --> 00:28:07,209
John Galetska is investigating

747
00:28:07,277 --> 00:28:08,577
whether the processes which

748
00:28:08,645 --> 00:28:10,179
built Everest continue

749
00:28:10,213 --> 00:28:12,381
to this day.

750
00:28:12,482 --> 00:28:14,583
He has traveled to the remotest

751
00:28:14,651 --> 00:28:16,819
regions of Nepal and India,

752
00:28:16,853 --> 00:28:18,654
setting up gps stations which

753
00:28:18,688 --> 00:28:20,389
he hopes will provide him with

754
00:28:20,490 --> 00:28:24,026
the answer.

755
00:28:24,127 --> 00:28:25,728
>> All right, I've come as far

756
00:28:25,762 --> 00:28:28,597
as I can by car, and I've got

757
00:28:28,665 --> 00:28:30,399
a 3-hour walk straight up

758
00:28:30,467 --> 00:28:32,935
the slope.

759
00:28:38,608 --> 00:28:42,311
>> [speaks foreign language]

760
00:28:42,379 --> 00:28:44,780
>> Just like a gps in a car,

761
00:28:44,848 --> 00:28:46,849
yhis station is able to pick up

762
00:28:46,883 --> 00:28:48,384
signals from satellites and

763
00:28:48,418 --> 00:28:50,286
monitor any movement of the

764
00:28:50,320 --> 00:28:51,987
ground.

765
00:28:52,022 --> 00:28:54,356
>> The gps station has been

766
00:28:54,391 --> 00:28:56,492
operating continuously for the

767
00:28:56,560 --> 00:28:59,895
last 5 years, so every second

768
00:28:59,930 --> 00:29:03,098
of every day of every month of

769
00:29:03,133 --> 00:29:05,634
every year, it's taking a data

770
00:29:05,669 --> 00:29:06,735
sample.

771
00:29:06,770 --> 00:29:10,406
And what it's looking for is

772
00:29:10,473 --> 00:29:14,043
changes in the position of where

773
00:29:14,110 --> 00:29:15,644
the station is, but how it's

774
00:29:15,679 --> 00:29:17,847
moving, the velocity of this

775
00:29:17,914 --> 00:29:19,815
station, believe it or not, and

776
00:29:19,850 --> 00:29:22,918
even changes in velocity.

777
00:29:22,953 --> 00:29:24,753
>> The readings from the gps

778
00:29:24,855 --> 00:29:27,590
show that India is still moving,

779
00:29:27,691 --> 00:29:30,693
about two inches every year.

780
00:29:30,760 --> 00:29:33,395
50 million years after its

781
00:29:33,463 --> 00:29:35,698
initial collision, it is still

782
00:29:35,765 --> 00:29:37,132
on its relentless journey

783
00:29:37,200 --> 00:29:39,134
northwards, pushing underneath

784
00:29:39,236 --> 00:29:40,402
Asia.

785
00:29:40,470 --> 00:29:42,304
And as it does so, Everest

786
00:29:42,372 --> 00:29:45,474
continues to be pushed higher.

787
00:29:45,575 --> 00:29:47,643
But there is a dark consequence

788
00:29:47,744 --> 00:29:51,747
to this mountain-building...

789
00:29:51,815 --> 00:29:54,283
earthquakes.

790
00:29:54,384 --> 00:29:55,851
>> So what's going on here in

791
00:29:55,919 --> 00:29:57,720
the Nepali Himalaya, we've got

792
00:29:57,754 --> 00:30:00,122
the Indian tectonic plates sort

793
00:30:00,190 --> 00:30:02,758
of ramming into Asia.

794
00:30:02,826 --> 00:30:05,027
In this case, India is losing

795
00:30:05,095 --> 00:30:06,762
out, it's being forced under

796
00:30:06,830 --> 00:30:08,230
Asia

797
00:30:08,265 --> 00:30:09,732
But it's unfortunate that

798
00:30:09,799 --> 00:30:11,734
they're locked frictionally, and

799
00:30:11,801 --> 00:30:13,769
eventually, over the course of

800
00:30:13,803 --> 00:30:16,639
hundreds of years, that strain

801
00:30:16,740 --> 00:30:18,073
is accumulated and then

802
00:30:18,108 --> 00:30:20,009
released suddenly in a giant

803
00:30:20,076 --> 00:30:21,644
earthquake.

804
00:30:21,711 --> 00:30:23,512
>> The Himalayas have seen 15

805
00:30:23,546 --> 00:30:25,281
major earthquakes in the past

806
00:30:25,348 --> 00:30:27,082
100 years.

807
00:30:27,150 --> 00:30:29,385
The most recent to hit was in

808
00:30:29,452 --> 00:30:34,290
Pakistan--October 8, 2005.

809
00:30:34,357 --> 00:30:38,360
The quake devastated the region.

810
00:30:38,461 --> 00:30:40,829
Galetska's readings show that

811
00:30:40,897 --> 00:30:42,197
another earthquake is on

812
00:30:42,265 --> 00:30:44,199
its way.

813
00:30:44,301 --> 00:30:45,801
Kathmandu, the capital of

814
00:30:45,835 --> 00:30:47,569
Nepal, lies in the center of

815
00:30:47,637 --> 00:30:49,838
the danger zone.

816
00:30:49,906 --> 00:30:51,473
>> When that earthquake

817
00:30:51,574 --> 00:30:54,743
happens--not if--when that

818
00:30:54,844 --> 00:30:56,478
earthquake happens, it's going

819
00:30:56,579 --> 00:30:58,847
to be several minutes of terror.

820
00:30:58,949 --> 00:31:00,282
There will be strong shaking in

821
00:31:00,350 --> 00:31:02,584
Kathmandu, there will be just

822
00:31:02,652 --> 00:31:06,455
collapsed structures.

823
00:31:06,489 --> 00:31:09,658
You will see landslides on all

824
00:31:09,726 --> 00:31:11,093
these mountains.

825
00:31:11,127 --> 00:31:12,561
It's going to be complete

826
00:31:12,629 --> 00:31:15,397
devastation.

827
00:31:15,498 --> 00:31:18,400
26 million people in Nepal,

828
00:31:18,501 --> 00:31:20,135
50 million people along the

829
00:31:20,203 --> 00:31:22,404
whole arc of the Himalayan

830
00:31:22,505 --> 00:31:24,306
range--all of these people

831
00:31:24,407 --> 00:31:27,276
will be affected.

832
00:31:30,780 --> 00:31:33,048
>> These devastating earthquakes

833
00:31:33,149 --> 00:31:34,950
are the result of a very active

834
00:31:35,051 --> 00:31:38,854
mountain belt--further evidence

835
00:31:38,922 --> 00:31:41,056
that Everest is being actively

836
00:31:41,124 --> 00:31:42,691
pushed upward.

837
00:31:42,759 --> 00:31:44,059
But there is a second force

838
00:31:44,127 --> 00:31:45,694
at work in these mountains--

839
00:31:45,762 --> 00:31:47,196
erosion.

840
00:31:47,230 --> 00:31:48,330
>> There's a constant battle

841
00:31:48,398 --> 00:31:50,199
going on in nature here between

842
00:31:50,233 --> 00:31:52,234
the uplift of the Himalayas and

843
00:31:52,335 --> 00:31:54,903
the down-cutting of erosion.

844
00:31:54,938 --> 00:31:57,473
>> Erosion in the Himalayas is

845
00:31:57,540 --> 00:31:59,641
ferocious.

846
00:31:59,676 --> 00:32:01,577
A clue as to the reason why

847
00:32:01,644 --> 00:32:03,579
lies in a small village 300

848
00:32:03,646 --> 00:32:05,647
miles east of Everest,

849
00:32:05,682 --> 00:32:08,584
Cherrapunji.

850
00:32:15,825 --> 00:32:17,226
It's the wettest place on

851
00:32:17,293 --> 00:32:19,661
planet earth, averaging over

852
00:32:19,763 --> 00:32:24,033
432 inches of rain each year.

853
00:32:24,134 --> 00:32:26,301
This place is 12 times wetter

854
00:32:26,369 --> 00:32:28,570
than Seattle, and the reason for

855
00:32:28,671 --> 00:32:30,572
all this rain?

856
00:32:30,673 --> 00:32:34,510
The monsoon.

857
00:32:34,577 --> 00:32:36,512
[thunderclap]

858
00:32:36,579 --> 00:32:38,781
>> The Indian monsoon system is

859
00:32:38,848 --> 00:32:40,482
an almost unique system on the

860
00:32:40,517 --> 00:32:42,684
planet, and the ultimate driving

861
00:32:42,752 --> 00:32:44,420
force is the high mountains

862
00:32:44,487 --> 00:32:45,954
And the high Himalayas and the

863
00:32:46,056 --> 00:32:48,157
Tibetan plateau, which is by

864
00:32:48,224 --> 00:32:50,426
far the largest area of high

865
00:32:50,493 --> 00:32:52,594
elevation on the planet today.

866
00:32:52,662 --> 00:32:54,797
And that causes this massive

867
00:32:54,864 --> 00:32:56,298
high-pressure system during the

868
00:32:56,332 --> 00:32:58,767
summer months, which results in

869
00:32:58,868 --> 00:33:01,503
the sucking in of all the warm,

870
00:33:01,571 --> 00:33:05,340
moist air from the Indian ocean.

871
00:33:05,408 --> 00:33:07,676
>> This seasonal weather system

872
00:33:07,710 --> 00:33:10,245
blows in across India.

873
00:33:10,313 --> 00:33:12,414
Clouds build and rise as they

874
00:33:12,515 --> 00:33:14,349
hit the high mountains and form

875
00:33:14,417 --> 00:33:16,485
heavy rains, which fall across

876
00:33:16,519 --> 00:33:18,520
India.

877
00:33:18,621 --> 00:33:20,155
Those rains reach their maximum

878
00:33:20,223 --> 00:33:21,423
on the southern slopes of

879
00:33:21,491 --> 00:33:23,625
The Himalayas.

880
00:33:23,693 --> 00:33:24,793
>> During the height of the

881
00:33:24,894 --> 00:33:26,528
summer monsoons, some of these

882
00:33:26,596 --> 00:33:29,431
rivers are able to rise by 20 or

883
00:33:29,499 --> 00:33:33,402
30 feet in one storm, so where

884
00:33:33,436 --> 00:33:34,903
I'm standing now, the levels of

885
00:33:34,971 --> 00:33:37,773
The river will be way up over

886
00:33:37,807 --> 00:33:39,541
here.

887
00:33:39,609 --> 00:33:42,778
>> Each year, 264 cubic miles

888
00:33:42,879 --> 00:33:45,114
of fresh water--enough to fill

889
00:33:45,148 --> 00:33:47,382
Hoover Dam's Lake Mead 30 times

890
00:33:47,417 --> 00:33:49,685
over--pours down the slopes of

891
00:33:49,752 --> 00:33:51,587
the mountains.

892
00:33:51,654 --> 00:33:53,422
This water feeds some of the

893
00:33:53,490 --> 00:33:55,424
largest rivers in the world:

894
00:33:55,525 --> 00:33:58,327
The Ganges, the indus, the

895
00:33:58,394 --> 00:34:01,396
Irrawaddy, and the Yangtze.

896
00:34:01,431 --> 00:34:02,965
The Himalayas are the water

897
00:34:03,066 --> 00:34:05,667
tower of Asia, supplying fresh

898
00:34:05,702 --> 00:34:07,336
water to a fifth of the world's

899
00:34:07,403 --> 00:34:10,139
population.

900
00:34:12,976 --> 00:34:14,710
But all this water is having a

901
00:34:14,777 --> 00:34:16,078
dramatic effect on the

902
00:34:16,146 --> 00:34:20,082
mountains.

903
00:34:20,150 --> 00:34:22,584
Fast-flowing rivers cut

904
00:34:22,619 --> 00:34:25,587
steep-sided valleys.

905
00:34:25,622 --> 00:34:27,222
High in the mountains, rain

906
00:34:27,257 --> 00:34:29,992
turns to snow, feeding glaciers

907
00:34:30,059 --> 00:34:31,360
which carve into the upper

908
00:34:31,427 --> 00:34:33,262
slopes.

909
00:34:33,329 --> 00:34:35,731
All these forces are at work

910
00:34:35,798 --> 00:34:38,066
today, wearing away at the

911
00:34:38,134 --> 00:34:41,236
Himalayan peaks.

912
00:34:41,271 --> 00:34:43,906
Because the monsoon is so

913
00:34:43,973 --> 00:34:46,175
powerful, geologists suspect

914
00:34:46,276 --> 00:34:48,076
that Everest and the Himalayas

915
00:34:48,144 --> 00:34:49,811
are being worn away perhaps

916
00:34:49,879 --> 00:34:51,613
more quickly than any other

917
00:34:51,714 --> 00:34:54,783
mountain belt in the world.

918
00:34:54,884 --> 00:34:58,921
Since 2004, a powerful new

919
00:34:58,988 --> 00:35:00,389
technique has emerged that can

920
00:35:00,456 --> 00:35:01,924
actually measure how fast a

921
00:35:01,991 --> 00:35:04,660
mountain is being worn away.

922
00:35:04,761 --> 00:35:07,462
It uses high-energy particles

923
00:35:07,497 --> 00:35:09,498
from space.

924
00:35:09,566 --> 00:35:10,832
>> At present, we're all being

925
00:35:10,900 --> 00:35:13,101
bombarded by cosmic rays.

926
00:35:13,136 --> 00:35:15,037
They come from distant parts of

927
00:35:15,104 --> 00:35:16,905
the galaxy.

928
00:35:16,940 --> 00:35:18,473
>> When these particles hit a

929
00:35:18,575 --> 00:35:20,375
rock surface, a chemical change

930
00:35:20,410 --> 00:35:22,110
happens.

931
00:35:22,212 --> 00:35:24,213
It's like a kind of cosmic

932
00:35:24,314 --> 00:35:26,949
sunburn.

933
00:35:27,050 --> 00:35:29,952
Erosion from rivers and glaciers

934
00:35:30,053 --> 00:35:32,020
expose rock surfaces to these

935
00:35:32,055 --> 00:35:34,690
cosmic rays.

936
00:35:34,757 --> 00:35:36,658
And just like sunburn, the

937
00:35:36,693 --> 00:35:38,760
longer the rock is exposed, the

938
00:35:38,861 --> 00:35:40,495
greater the damage to its

939
00:35:40,597 --> 00:35:42,497
surface.

940
00:35:42,565 --> 00:35:44,233
By measuring the amount of

941
00:35:44,334 --> 00:35:46,335
cosmic sunburn in the rocks,

942
00:35:46,402 --> 00:35:48,403
geologists can figure out how

943
00:35:48,504 --> 00:35:50,239
quickly rivers and glaciers are

944
00:35:50,306 --> 00:35:52,741
cutting into the mountains.

945
00:35:52,775 --> 00:35:54,109
But working this out needs

946
00:35:54,143 --> 00:35:56,245
very precise science.

947
00:35:56,312 --> 00:35:57,579
>> the concentrations that we're

948
00:35:57,614 --> 00:35:59,214
Trying to measure are so small,

949
00:35:59,249 --> 00:36:00,682
they're equivalent to putting a

950
00:36:00,750 --> 00:36:01,783
pinch of salt in an

951
00:36:01,884 --> 00:36:03,151
Olympic-size swimming pool and

952
00:36:03,219 --> 00:36:04,486
measuring one or two grains of

953
00:36:04,520 --> 00:36:05,787
that salt.

954
00:36:05,888 --> 00:36:07,789
>> After years of research,

955
00:36:07,857 --> 00:36:09,424
Owen has discovered the maximum

956
00:36:09,525 --> 00:36:13,061
speed of erosion...

957
00:36:13,129 --> 00:36:16,598
1.1 inches per year.

958
00:36:16,699 --> 00:36:18,800
That's 6 times faster than

959
00:36:18,868 --> 00:36:20,335
the Rocky Mountains and faster

960
00:36:20,403 --> 00:36:21,870
than anywhere else on the

961
00:36:21,971 --> 00:36:23,972
Planet.

962
00:36:24,040 --> 00:36:26,074
>> All mountains suffer from

963
00:36:26,142 --> 00:36:27,309
erosion.

964
00:36:27,343 --> 00:36:28,910
They're built up by tectonic

965
00:36:28,978 --> 00:36:30,679
forces, and erosion wipes them

966
00:36:30,713 --> 00:36:32,147
down again.

967
00:36:32,248 --> 00:36:33,782
The Alps, the Rocky Mountains,

968
00:36:33,816 --> 00:36:36,518
the Andes all have erosional

969
00:36:36,619 --> 00:36:38,954
potential, but nowhere has such

970
00:36:38,988 --> 00:36:40,989
huge erosional potential as the

971
00:36:41,090 --> 00:36:41,890
Himalayas.

972
00:36:41,958 --> 00:36:43,992
The erosion here is far greater

973
00:36:44,093 --> 00:36:45,694
than anywhere else, and the

974
00:36:45,728 --> 00:36:47,429
main reason for that is the

975
00:36:47,463 --> 00:36:48,730
summer monsoon.

976
00:36:48,798 --> 00:36:49,965
[thunder]

977
00:36:49,999 --> 00:36:51,533
>> The battle in nature between

978
00:36:51,601 --> 00:36:53,735
uplift and erosion continues,

979
00:36:53,803 --> 00:36:56,271
but the question remains:

980
00:36:56,372 --> 00:36:58,640
Which one is winning?

981
00:36:58,708 --> 00:37:02,377
Is Everest shrinking or growing?

982
00:37:02,445 --> 00:37:05,180
In 1999, a team of geologists

983
00:37:05,248 --> 00:37:07,349
set out to answer this question.

984
00:37:07,383 --> 00:37:09,818
They placed a small gps station

985
00:37:09,886 --> 00:37:14,456
near to the summit of Everest.

986
00:37:14,557 --> 00:37:16,558
After two years of monitoring,

987
00:37:16,626 --> 00:37:18,627
the team had their answer.

988
00:37:18,728 --> 00:37:21,263
Everest was, in fact, still

989
00:37:21,297 --> 00:37:23,832
growing--a quarter of an inch

990
00:37:23,900 --> 00:37:25,734
every year.

991
00:37:25,835 --> 00:37:27,302
The world's tallest mountain

992
00:37:27,370 --> 00:37:30,372
Is still getting taller.

993
00:37:30,473 --> 00:37:31,807
The investigation into the

994
00:37:31,841 --> 00:37:32,941
growth and movement of the

995
00:37:33,009 --> 00:37:34,376
Himalayas has revealed the

996
00:37:34,444 --> 00:37:36,278
following evidence:

997
00:37:36,379 --> 00:37:39,081
Gps data shows a very active

998
00:37:39,115 --> 00:37:40,349
mountain belt that is still

999
00:37:40,383 --> 00:37:44,086
uplifting; cosmic ray dating

1000
00:37:44,120 --> 00:37:45,721
proves that the Himalayas are

1001
00:37:45,755 --> 00:37:47,289
being eroded faster than

1002
00:37:47,390 --> 00:37:53,028
anyplace else on earth.

1003
00:37:53,096 --> 00:37:55,030
Geologists now have the tools

1004
00:37:55,098 --> 00:37:57,132
to predict Everest's future.

1005
00:37:57,200 --> 00:37:58,834
It, and the Himalayan Mountain

1006
00:37:58,935 --> 00:38:01,837
chain, will continue to rise.

1007
00:38:01,904 --> 00:38:03,672
Aided by new technology,

1008
00:38:03,740 --> 00:38:05,407
discoveries are still being

1009
00:38:05,475 --> 00:38:07,542
made in the Himalayas, and

1010
00:38:07,577 --> 00:38:09,778
recently, one reveals that the

1011
00:38:09,846 --> 00:38:11,646
rise of these mountains was so

1012
00:38:11,681 --> 00:38:13,348
immense that it might have

1013
00:38:13,416 --> 00:38:15,117
changed the very course of

1014
00:38:15,218 --> 00:38:17,219
Earth's history and plunged the

1015
00:38:17,286 --> 00:38:19,688
entire planet into a deep

1016
00:38:19,756 --> 00:38:20,671
freeze.

1017
00:38:22,822 --> 00:38:25,223
>> Everest, 50 million years

1018
00:38:25,291 --> 00:38:27,392
in the making.

1019
00:38:27,460 --> 00:38:29,327
Today the Himalayas stand as

1020
00:38:29,395 --> 00:38:31,696
the biggest, highest, and most

1021
00:38:31,764 --> 00:38:33,131
active mountain range on the

1022
00:38:33,232 --> 00:38:34,933
Planet.

1023
00:38:34,967 --> 00:38:36,301
They are mountains of

1024
00:38:36,402 --> 00:38:39,571
superlatives: The deepest

1025
00:38:39,605 --> 00:38:41,506
Valley, falling over 20,000

1026
00:38:41,574 --> 00:38:44,109
vertical feet; the highest

1027
00:38:44,143 --> 00:38:46,511
Plateau; the longest sheer

1028
00:38:46,612 --> 00:38:50,048
rock face; hundreds of peaks

1029
00:38:50,149 --> 00:38:51,616
higher than anywhere else on

1030
00:38:51,684 --> 00:38:53,852
Earth, and many have never even

1031
00:38:53,953 --> 00:38:56,955
been named.

1032
00:38:57,023 --> 00:38:59,124
The formation of the Himalayas

1033
00:38:59,191 --> 00:39:00,625
has changed the entire

1034
00:39:00,660 --> 00:39:03,294
landscape, an epic evolution

1035
00:39:03,396 --> 00:39:04,929
from ocean to immense

1036
00:39:04,997 --> 00:39:07,565
mountain range,

1037
00:39:07,633 --> 00:39:10,201
and created one of the world's

1038
00:39:10,302 --> 00:39:12,837
most important weather systems--

1039
00:39:12,938 --> 00:39:15,106
The monsoon, which supplies

1040
00:39:15,141 --> 00:39:16,841
fresh water to one-fifth of the

1041
00:39:16,942 --> 00:39:20,045
world's population.

1042
00:39:20,112 --> 00:39:23,048
[thunderclap]

1043
00:39:23,115 --> 00:39:25,316
>> The Himalayas and Tibet

1044
00:39:25,418 --> 00:39:26,751
are really exciting places to

1045
00:39:26,786 --> 00:39:28,053
work for a geologist.

1046
00:39:28,120 --> 00:39:29,287
This is because it's such an

1047
00:39:29,321 --> 00:39:30,422
an active and dynamic

1048
00:39:30,489 --> 00:39:31,690
environment.

1049
00:39:31,757 --> 00:39:33,391
Not only that, it's a very

1050
00:39:33,426 --> 00:39:37,028
important area climatically.

1051
00:39:37,096 --> 00:39:38,630
>> Scientists investigating the

1052
00:39:38,664 --> 00:39:40,198
Himalayas have uncovered some

1053
00:39:40,266 --> 00:39:42,033
surprising results...

1054
00:39:42,101 --> 00:39:43,735
[thunder]

1055
00:39:43,803 --> 00:39:45,737
discoveries which would suggest

1056
00:39:45,805 --> 00:39:47,272
that the rise of the Himalayas

1057
00:39:47,306 --> 00:39:49,808
might have had an impact on the

1058
00:39:49,842 --> 00:39:54,679
climate of the entire planet.

1059
00:39:54,714 --> 00:39:56,915
The discovery came about almost

1060
00:39:56,982 --> 00:39:58,883
by accident, while scientists

1061
00:39:58,918 --> 00:40:00,719
were studying a process called

1062
00:40:00,820 --> 00:40:03,354
chemical weathering.

1063
00:40:03,422 --> 00:40:05,990
Every time it rains, carbon

1064
00:40:06,058 --> 00:40:07,726
dioxide in the atmosphere

1065
00:40:07,793 --> 00:40:10,962
dissolves to form acid rain.

1066
00:40:10,996 --> 00:40:12,464
When the rain falls, it eats

1067
00:40:12,531 --> 00:40:14,466
away at rock surfaces.

1068
00:40:14,533 --> 00:40:16,167
This weathering process takes

1069
00:40:16,202 --> 00:40:18,369
co2 out of the atmosphere and

1070
00:40:18,437 --> 00:40:21,106
locks it away in the rocks.

1071
00:40:21,173 --> 00:40:22,273
>> as that rock is interacting

1072
00:40:22,374 --> 00:40:23,241
With the atmosphere, it pulls

1073
00:40:23,275 --> 00:40:25,276
down carbon dioxide, and that

1074
00:40:25,344 --> 00:40:27,378
leads to a negative greenhouse

1075
00:40:27,446 --> 00:40:28,346
effect, if you like,

1076
00:40:28,380 --> 00:40:29,714
An icehouse effect.

1077
00:40:29,749 --> 00:40:31,349
So you get more weathering,

1078
00:40:31,383 --> 00:40:33,017
you pull down that carbon

1079
00:40:33,085 --> 00:40:34,452
dioxide out of the atmosphere,

1080
00:40:34,520 --> 00:40:37,188
and that leads to cooling.

1081
00:40:37,289 --> 00:40:39,524
>> The more co2 there is in

1082
00:40:39,558 --> 00:40:41,092
the atmosphere, the warmer the

1083
00:40:41,193 --> 00:40:42,927
global temperatures.

1084
00:40:43,028 --> 00:40:45,530
Take co2 out of the atmosphere

1085
00:40:45,564 --> 00:40:48,967
and temperatures are reduced.

1086
00:40:49,001 --> 00:40:51,636
Then scientists discovered

1087
00:40:51,704 --> 00:40:53,605
a major coincidence.

1088
00:40:53,639 --> 00:40:56,908
The dramatic rise of the

1089
00:40:56,976 --> 00:40:58,810
Himalayas over the past 20

1090
00:40:58,878 --> 00:41:00,812
million years coincided with

1091
00:41:00,913 --> 00:41:02,714
the gradual fall of global

1092
00:41:02,815 --> 00:41:05,717
temperatures, which led to the

1093
00:41:05,785 --> 00:41:10,822
start of the last major ice age.

1094
00:41:10,923 --> 00:41:12,524
The pieces of the puzzle fell

1095
00:41:12,558 --> 00:41:14,626
into place.

1096
00:41:14,693 --> 00:41:17,362
As the Himalayas uplifted, they

1097
00:41:17,463 --> 00:41:19,464
had acted like an ever-growing,

1098
00:41:19,532 --> 00:41:21,633
giant sponge and absorbed

1099
00:41:21,734 --> 00:41:23,835
massive amounts of co2 from

1100
00:41:23,903 --> 00:41:26,271
the atmosphere.

1101
00:41:26,338 --> 00:41:28,740
>> The uplift of the Himalayas

1102
00:41:28,808 --> 00:41:30,742
and Tibet leading to the draw

1103
00:41:30,843 --> 00:41:32,477
down of carbon dioxide from the

1104
00:41:32,545 --> 00:41:34,479
atmosphere by these weathering

1105
00:41:34,547 --> 00:41:36,614
processes was probably one of

1106
00:41:36,649 --> 00:41:38,383
the major factors in leading to

1107
00:41:38,450 --> 00:41:40,285
The cooling that culminated in

1108
00:41:40,386 --> 00:41:42,453
the ice age that started about

1109
00:41:42,555 --> 00:41:43,488
two and a half million years

1110
00:41:43,556 --> 00:41:45,757
before present.

1111
00:41:45,825 --> 00:41:47,759
>> A cooling effect which was

1112
00:41:47,827 --> 00:41:50,361
so intense that 2.5 million

1113
00:41:50,396 --> 00:41:52,564
years ago, it contributed to a

1114
00:41:52,665 --> 00:41:55,567
global deep freeze,

1115
00:41:55,668 --> 00:41:57,635
an ice age that affected the

1116
00:41:57,670 --> 00:42:00,672
entire planet and had a dramatic

1117
00:42:00,739 --> 00:42:05,743
impact on all life on earth.

1118
00:42:05,845 --> 00:42:07,178
[thunderclap]

1119
00:42:07,213 --> 00:42:09,013
And geologists are sure that

1120
00:42:09,048 --> 00:42:10,548
the Himalayas will continue to

1121
00:42:10,583 --> 00:42:12,483
exert an immense influence on

1122
00:42:12,518 --> 00:42:14,853
our planet, as these mountains

1123
00:42:14,954 --> 00:42:17,488
are still growing.

1124
00:42:17,556 --> 00:42:19,390
As India pushes northwards

1125
00:42:19,491 --> 00:42:21,659
under Asia, the building cycle

1126
00:42:21,727 --> 00:42:24,128
continues, more mountains will

1127
00:42:24,230 --> 00:42:25,463
form.

1128
00:42:25,497 --> 00:42:27,398
Over the next 10 million years,

1129
00:42:27,499 --> 00:42:29,868
300 miles of land will be forced

1130
00:42:29,935 --> 00:42:31,736
under Asia.

1131
00:42:31,770 --> 00:42:33,872
The entire range will grow

1132
00:42:33,939 --> 00:42:36,107
even taller.

1133
00:42:36,141 --> 00:42:38,776
Out in this vast wilderness of

1134
00:42:38,878 --> 00:42:41,479
icy peaks, geologists are still

1135
00:42:41,513 --> 00:42:43,581
making discoveries.

1136
00:42:43,682 --> 00:42:44,949
>> For geologists, it's exciting

1137
00:42:45,017 --> 00:42:46,284
in terms of the science because

1138
00:42:46,318 --> 00:42:47,418
you get to areas where few

1139
00:42:47,519 --> 00:42:49,020
geologists have been before.

1140
00:42:49,054 --> 00:42:50,421
>> As the research continues

1141
00:42:50,489 --> 00:42:51,956
at Everest and across the

1142
00:42:52,024 --> 00:42:54,058
Himalayas, it is a wonder what

1143
00:42:54,159 --> 00:42:55,860
secrets they might tell us in

1144
00:42:55,961 --> 00:42:59,163
the future.

1145
00:42:59,231 --> 00:43:00,865
The evidence for Everest's

1146
00:43:00,966 --> 00:43:02,667
incredible geological journey

1147
00:43:02,701 --> 00:43:04,402
has been revealed:

1148
00:43:04,436 --> 00:43:06,938
Ammonites, evidence that an

1149
00:43:06,972 --> 00:43:09,073
ocean once existed between India

1150
00:43:09,141 --> 00:43:10,508
and Asia, and that the

1151
00:43:10,576 --> 00:43:12,610
continents collided 50.5

1152
00:43:12,678 --> 00:43:14,779
million years ago;

1153
00:43:14,880 --> 00:43:17,782
Folds and faults--proof of the

1154
00:43:17,883 --> 00:43:19,250
initial mountain-building

1155
00:43:19,318 --> 00:43:22,954
process; granite--evidence of

1156
00:43:22,988 --> 00:43:24,522
a giant conveyor belt of

1157
00:43:24,590 --> 00:43:26,057
mountain-building power which

1158
00:43:26,091 --> 00:43:28,059
pushed Everest to its immense

1159
00:43:28,127 --> 00:43:30,528
height;

1160
00:43:30,596 --> 00:43:33,164
Gps data reveals that the

1161
00:43:33,265 --> 00:43:34,632
Himalayas are the most active

1162
00:43:34,667 --> 00:43:37,001
mountain range on the planet,

1163
00:43:37,069 --> 00:43:40,405
and Everest is still growing.

1164
00:43:43,175 --> 00:43:44,709
Everest today stands as the

1165
00:43:44,777 --> 00:43:47,345
highest place on planet earth.

1166
00:43:47,446 --> 00:43:49,180
But in millions of years to

1167
00:43:49,281 --> 00:43:51,549
come, there will perhaps be

1168
00:43:51,617 --> 00:43:53,284
another mountain big enough to

1169
00:43:53,352 --> 00:43:55,353
challenge this giant--

1170
00:43:55,454 --> 00:43:57,521
living proof that the earth is

1171
00:43:57,522 --> 00:43:58,522
never at rest.

1172
00:43:58,523 --> 00:44:00,023
-- Sync, corrected by elderman --
-- for MY-SUBS.com ---