Original subtitles

Since its creation, the Earth has never stopped changing.

Colossal forces have hurled ocean floors upwards and made them into towering mountain ranges.

Incredible collisions have created entire continents.

These tectonic forces are still at work today.

We see them in volcanic eruptions, earthquakes, and tsunamis.

Tectonics sculpt our landscapes, change our climates, dry up our oceans, and can destroy life.

The history of Oceania is like the history of the Earth itself.

The smallest of the continents has known the best and the worst of times.

The beginnings of life itself and also much of its destruction.

Antarctica was attached for millions of years to Oceania's largest landmass, Australia,

which is for now the most geologically stable place on the planet.

Its neighbor, New Zealand, is not so lucky.

It's in the middle of a tectonically explosive region called the Ring of Fire.

It's all part of the endless voyage of the continents.

Oceania is an enormous archipelago.

It includes more than 25,000 islands, some almost as old as the Earth itself.

Four and a half billion years ago, the Earth was a ball of liquid matter.

There was no surface.

Any solid ground was constantly melting back into the cauldron of the Earth's burning core.

Scientists had long believed that the first bits of solid crust only appeared when the

Earth had cooled down enough.

But a recent discovery in Western Australia has turned this concept on its head.

Simon Wilde of Curtin University of Technology and Perth has been studying crystals that

were formed when our planet was very young.

During the formation of the first bits of solid matter, crystallized minerals were formed.

These minerals were soon subjected to the most intense volcanic activity in our planet's

history.

These ancient crystals are called zircons, and it's amazing that the ones Simon has

found have survived until today.

They are the oldest existing matter on Earth.

Their structure can reveal billions of years of history.

They are, in fact, the Earth's first historical record.

Zircon requires a granitic rock to grow in, and so it tells us that rocks of granite composition

were around 4.4 billion years ago, which is very interesting because previously people

didn't believe that continental crust existed at this time, about 150 million years since

the formation of the solar system.

So this has really changed our view of the early Earth.

Instead of being a hot boiling magma ocean and meteorites banging into it, what we believe

now by 4.4, the Earth had cooled sufficiently to have continents, oceans, and some form of

atmosphere.

It may well be a CO2-rich atmosphere, but there was an atmosphere nonetheless.

This is known as the Dark Ages, because there was no rock record.

Now with the discovery of these crystals, we are actually shining light on those Dark Ages.

The oldest existing crystal on our planet was found in Western Australia.

In the two billion years since the formation of the Earth, small islands of crust began

to emerge on the fiery surface of the planet.

When these islands joined up, they formed the first pieces of continental land called

Kratons.

The Pilbara region of Western Australia is one of those ancient continental islands.

It is one of the most geologically stable areas in the world.

For billions of years, the Pilbara has protected geological treasures that would have been

destroyed anywhere else.

Few know the Pilbara better than Martin van Crenendonk, who's one of the few persons to

have mapped it.

He has spent ten years searching out the rocks that tell the history of Oceania and our planet.

One of the greatest stories about Earth's history is how our planet changed from a very

primitive, nasty place where it was very difficult for life to get a foothold to this modern

world with its beautiful blue skies and oxygenated atmosphere, where life is very complex and

abundant.

And we've been studying those rocks over the last few years, and it turns out they have

answers to some of these very important questions about how did life evolve and how did we get

here.

Martin has found astonishing things in the Pilbara.

It was here that he discovered rock formations that may hold the key to understanding how

life on Earth evolved from bacteria to us.

Look at these little beauties.

Aren't they gorgeous?

These structures in the rocks here in front of me are called stromatolites.

These are structures formed by colonies of living microorganisms.

The intriguing thing about these rocks is that although they look a little bit like sedimentary

structures you'd see on the beach, you know, normal ripples, which everybody recognizes,

these little wavelets when the water moves over the sand, these are actually quite different.

When you look at them in three dimensions, they are actually cone shaped.

They actually start from a flat level and then start growing upwards, sometimes over

tens or even hundreds of meters.

And it's these kinds of observations which make us distinguish or help us distinguish

between, you know, physical geology and something that's actually got the signature of early

life.

And don't forget, these rocks are 3.4 billion years old.

These rocks may be inanimate today, but three and a half billion years ago they were very

much alive.

Although the world they lived in was nothing like the world around us today.

At that time there was little solid ground and most of what was there was volcanic.

The oceans were full of iron and were green.

The sky was orange, an atmosphere of methane, ammonia and carbon monoxide.

Not a place for human beings.

But it all changed around a billion years ago when the stromatolites colonized the oceans.

Two billion years ago something completely different happened.

There was a change in the atmosphere from being rich in carbon dioxide and other gases

like sulfur dioxide coming mostly from volcanoes to an atmosphere that was building up more

and more oxygen.

And oxygen is not a naturally forming free molecule.

It's a molecule that's produced by life processes, by photosynthesis.

Photosynthesis uses our beautiful sunlight energy and water to make body parts carbon

and then gives off O2.

The stromatolites transformed the atmosphere and left a record of their achievement carved

into the rocks.

But this is it right here.

This is a transition where we see the real change from early earth into more modern earth.

At this point, right in this little outcrop section behind me, these rocks pulled a story

that's as important as the time when the dinosaurs when extinct on earth from that giant meteorite

about 65 million years ago.

These rocks are two and a half billion years and record the first time when an early, very

sulfurous, gaseous kind of earth changed forever into a cool, much more modern earth.

And that contact is right down here where you have deposits of banded iron formation

grading up through red-colored iron-rich and gray shirts and then bang right there where

I can put my fingernail on the contact.

You have the change to modern earth.

And this outcrop is probably the most exciting one I've ever seen in my 25 years of doing

geology.

It just encapsulates in, you know, a few tens of centimeters this fundamental change when

earth irreversibly became modern.

But the oxygen that was freed by the stromatolites three billion years ago did not help what

life existed at the time.

Quite the opposite, in fact.

When life became more complex and started giving off oxygen, it's actually a pollutant

to most of the earlier forms of life.

They can't thrive with oxygen.

Life evolved to adapt to that new chemical reality.

And in fact, because it's harder to make life with oxygen around, life became more sophisticated.

But that evolved slowly over time and only because they actually had to get smarter to

live with this pollutant called oxygen around and evolve a more complex way of living.

Those stromatolites transformed more than terrestrial life.

They also changed the nature of the seas.

The oxygen they gave off turned the oceans from green to red.

Deposits of rust lay quietly on the ocean floor until huge tectonic forces thrust them

above the surface.

These impressive red mountains are now over a kilometer high.

They are made up of layers of what geologists call banded iron.

These are the remains of the massive amounts of rust that lay on the ocean floor.

At Shark Bay on the west coast of Australia, the descendants of the ancient stromatolites

who reigned over the world's oceans two billion years ago can still be seen.

A drive of just a few kilometers takes Martin van Cronendonk several billion years back

in time.

Shark Bay is a haven for a very special type of limestone, an unusual living rock made

up of alternating layers of crystallized minerals and blue-green algae.

These structures are called thrombolytes and they're a type of living rock made by colonies

of microorganisms.

An amazing thing about them is they just grow like a tree year by year adding layer upon

layer in these beautiful cone shapes because they're actually growing up towards the light

to get the food energy that they need from sunlight.

And these structures would have covered hundreds of kilometers of the sea bed because there

was nothing to graze on them.

They were the only living life forms and they covered the entire oceans and just pumped

out this enormous volume of oxygen that eventually changed our planet.

Day after day the thrombolytes at Shark Bay absorb the molecules of water surrounding

them, decompose them and release oxygen.

This is the same process used long ago by their ancestors, the stromatolites.

To the northeast of Shark Bay is the Hammersley Range.

Its massive deposits of iron have attracted prospectors who are digging into the mountains

to expose layers of banded iron.

If there's enough iron in these core samples, the red hills of Hammersley oxidized by ancient

stromatolites will be gutted and stripped of their minerals.

One company alone operates 12 mines in the region.

The company has built entire towns and constructed a private railway over 1400 kilometers long.

A hundred million tons of iron ore a year is taken from the Hammersley Range.

Much of it goes to Asia to build cars and cities.

Two and a half billion years ago the Pilbara region barely survives the violent volcanic

activity around it.

But as the earth cools, other small islands join Pilbara.

This ever-widening raft of crust becomes Australia.

As time passes all the other emerging land masses join into a single supercontinent,

Gondwana.

Australia finds itself welded to Antarctica.

This collision of Australia with Antarctica occurs on Australia's south coast, yet the

events' consequences reach as far as the middle of the Australian outback.

Near the border of the Northern Territory in South Australia, a new mountain range rises

up, the Peterman Mountains, with peaks as high as the Alps.

After 550 million years of erosion, this is all that remains.

This impressive natural wonder is Australia's most famous landmark, Ayers Rock, also known

by its aboriginal name Uluru.

Uluru began its existence as a huge sand dune.

Over time the dune was cemented into a sandstone island.

Tectonic forces lifted Uluru, turning it every which way.

Some horizontal layers even ended up being vertical.

Like an iceberg, only the tip of Uluru is visible.

Although it rises to a height of 350 meters, its base extends six kilometers below the

surface.

In the open air, its smooth surface has prevented it from being eroded by wind and water.

Collisions between the continents caused a number of cataclysms that transformed southern

Australia forever.

Jim Gilling of the South Australian Museum is both a geologist and a paleontologist.

Jim is returning to the site of an exceptional discovery he made in the middle of Australia's

south coast.

At the foot of the dry Iriakara Hills, Germanist team found traces of an ocean floor that

dried up hundreds of millions of years ago.

When you go back 550 to 560 million years, you're looking at a shallow sea floor with

some distance to the west and open ocean to the east.

While it's an ocean, sediment keeps accumulating and it keeps a record of everything that's

happened during the time of that ocean.

But one day a sea floor will be pushed up into giant folds and pushed into mountains.

As Gondwana formed, the landscape constantly changed.

550 million years ago, the collision of great land masses gave rise to the Flinders Ranges,

the largest mountain chain of South Australia.

Over time, many of its peaks have eroded and revealed a marine world that existed more

than 500 million years ago.

If the Flinders Ranges had never existed, we wouldn't be here because the only way of

actually seeing these layers would be to drill down into the earth, perhaps 500 metres, perhaps

5000 metres, because every layer would be buried.

It's only when these layers are buckled up and thrust through to the surface that we

can see the frayed edges of the sedimentary layers.

Jim and his team have dug up dozens of pieces of ancient seabed.

Put together, this marine jigsaw puzzle takes us back 560 million years.

We can see the undulations of a vanished sea preserved in sandstone.

But the most extraordinary discovery is a rare trace of ancient animal life.

OK, it's a nice surface.

It's very reminiscent of the bed we have over on the west side.

Mary Drozer is a professor of earth sciences at the University of California Riverside.

She's been working with Jim for more than 10 years.

The two researchers believe that the translucent marine animals of Idiakara mark the beginning

of a completely new stage of life on earth.

But if you get down on your hands and knees, you can see earth's first experiment in terms

of an animal marine community.

One of them had backbones.

Preservation of soft-bodied organisms is really rare.

So when you think about preservation of dinosaurs, what do we get?

We get the bones.

We don't get their soft parts.

What we see here is we're actually getting soft-part preservation.

It's like preserving a worm in rock.

That's just unimaginable.

But this was a very special window in terms of preservation.

And what's so cool about it is that it's earth's first experiment with animal life.

The Idiakara ecosystem brought to life by tectonic movement continues to surprise the

researchers.

Here's another one.

Look at that.

You can see in the light the first time in 560 million years.

So if you look at something like this guy here, this is spragina.

It's pretty common during this time.

And when you look at it, it almost appears to have a head and a body behind.

Now we're not sure.

Some people have suggested that actually that's an anchor and it stood up in the seafloor.

So we don't really understand it.

But certainly it's got quite a developed and complex body.

This trace fossil here you can see is just a millimeter in width.

This would have been a small organism.

We have no idea what made it.

But we can see the furrows on the edge that it would have been moving through the sediment.

So these trace fossils are really important because it's the oldest unequivocal evidence

of bilaterians.

And bilaterians, we are interested in bilaterians because we are bilaterians.

We are bilaterally symmetrical.

And we think in terms of all advanced organisms other than corals and sponges as being bilaterians.

And it gives a bit of cushioning effect too.

Many scientists believe that the Idiakara marine animals were our most distant cousins.

They were annihilated by tectonic movements and environmental changes.

But their existence on Earth lasted for more than 40 million years.

Two hundred and fifty million years ago, about one thousand kilometers from the Flinders

ranges, tectonics gave birth to the Blue Mountains.

These mountains were sculpted by tectonic forces over a period of millions of years.

The steep rock faces and deep valleys are home to several unique species including millions

of giant kangaroos.

They are here because of a tectonic movement that may have been the most important event

in the history of Australia.

Paleontologist Ann Musser works at the Australian Museum.

As she makes her way to the bottom of this cave, she is traveling deep into the history

of marsupials.

She has discovered that the genolin caves in the Blue Mountains are literally marsupial

graveyards.

Caves are perfect traps.

You don't really see the holes.

If you're a kangaroo, you're hopping over the top of the surface.

You might not see it.

You go right down through tubes, through holes, through caves, and you can't get back out

again.

Oh my gosh, it's just a little young rump.

The ancestors of these animals made an extraordinary journey.

It is really exciting to be working on these unique Australian marsupials.

Your ancestors came from Asia.

150 million years ago, Asia, Antarctica, and India are all still part of the supercontinent

of Gondwana.

At this time, the marsupials are being driven out of Asia by mammals and dinosaurs.

Their survival is only assured when the Antarctica Australian block breaks off from Gondwana.

Those who miss the boarding of this tectonic life raft do not survive.

However, not all the marsupial species are saved.

Sometime after 50 million years, Australia, as we know it now, broke away from Antarctica,

and it took with it that cargo of marsupials.

And the ancient platypus and other sorts of monotremes often went, the Antiquity and

the Rock, the animals on it were to evolve in isolation and become completely unique.

This is the southern edge of the Niddlebar Plain, a 1200 kilometer long line of coastal

cliffs.

It was formed when tectonic forces tore the Australian Antarctic block apart.

These formations of granite are echoed in Antarctica, the other side of a continental

wound that is never healed.

After reaching the southernmost point on Earth, Antarctica became the coldest of the continents.

Over the millennia, it was covered with thick ice which has prevented researchers from knowing

the exact nature of the underlying mantle.

This frozen world is larger than all the land masses of Oceania combined.

Just to say, Antarctica was completely transformed by tectonics after its separation from its

Australian sister.

In Tasmania, southeast of Australia, the rift left spectacular evidence.

At Cape Pillar, the two continental plates separated in an explosion of lava that accumulated

on the Tasmanian sedimentary floor.

Over time, the sea cooled the lava, which has remained in place ever since.

These columns of magma resemble the pipes of the world's biggest organ and are a striking

reminder of the separation of the two continents.

Since it broke off from Antarctica, the plate that Australia rests upon has been moving

northward at a rapid pace, six centimeters per year, making it the fastest moving plate

on the planet.

And it's not a peaceful voyage.

North of the continent, the Australian and the Pacific plates are colliding.

The perimeter of the Pacific plate is referred to as the Ring of Fire and is one of the most

unstable and dangerous zones on Earth.

Imagine that this is the Pacific plate, this is the Australian plate, and the two are in

collision.

What we have is a slow-motion tectonic car crash, and the result?

Earthquakes, volcanoes, tsunami, landslides, these spectacular mountains, and more often

the knot in death and destruction.

Geologist Hamish Campbell is fascinated by the meeting of the Australian and Pacific plates.

A stride the rift that separates these two landmasses is New Zealand.

In New Zealand's South Island, tectonic forces created an impressive mountain range called

the Southern Alps.

It's among the world's youngest mountain ranges, the visible face of the clash of tectonic

plates.

It's fantastic.

What these mountains represent is the very soft, westernmost edge of the Pacific plate,

and they are crumpling up, they're being washed against the much stronger Australian

plate, and they're going up at about a maximum of 10 millimetres a year.

And of course as fast as they're coming up, these rocks are being eroded just as a consequence

of normal weather, rain, no ice.

Alongside New Zealand's Southern Alps, and crossing almost the entire South Island, is

the boundary between the Australian and Pacific plates.

It's called the Alpine Fault.

And it's one of the tectonic marvels of the world.

Near this fault, earthquakes can occur at any moment.

In fact, New Zealand has an average of 14,000 earthquakes a year.

When the Alpine Fault shudders, it can lift the Southern Alps several metres in just a

few seconds.

The Alpine Fault is not the result of a frontal collision.

The Australian and the Pacific plates are actually sliding violently against one another.

Look at this landscape, it really is chewed up.

The fault moves in this sense, okay?

So the Pacific side is going south, and the Australian side is going north, and it does

so, let's see.

Every time it moves, it moves sideways between 7 and 13 metres, and vertically between 2

and 4 metres.

That's a lot of movement.

And it last moved in 1717.

We think that on average it moves about every 200 to 300 years, and that's based on a lot

of research.

Now, 1717 is about 300 years ago, so it's going to move again soon in the future.

My colleagues tell me that there's more than a 35% chance of this fault moving within the

next 50 years.

So that's the forecast.

And by the way, we're standing on the Australian plate here, and that's where I'd like to

be.

It's actually more stable than the Pacific plate.

But Punakaiki, on the west coast of South Island, visitors can admire rock formations

that resemble stacks of pancakes.

These strange layers of limestone were formed deep underwater and were then pushed up to

the surface.

These odd formations have made Hamish Campbell wonder about the geological history of his

country.

Could New Zealand have been completely submerged before being lifted above the Pacific Ocean?

Although most scientists don't agree with this hypothesis, Hamish thinks it's worthy

of discussion.

We know that a very substantial chunk of eastern Gondwana land broke away 83 million years

ago and moved off to the northeast.

And as it did so, it slowly sank.

And it did so for 60 million years.

Although most people are unaware of this, New Zealand is 12 times bigger than it appears

if you count the part that's underwater.

We call this underwater continent Zelandia.

And New Zealand is just the emergent highland part of this sunken continent.

New Zealand has literally been pushed up within the last 23 million years.

So there's a really interesting mystery to be solved here.

And that is, could it be that New Zealand was totally submerged just 23 million years

ago?

It's a challenging task for Hamish.

He has to travel the country from the coast to the top of the mountains.

He's on the lookout for rock formations that have recorded his country's underwater past.

What we want to do is have a look at this limestone.

So what you want us to do is stop this down here.

Hamish is on his way to sample the sedimentary rocks of South Island.

Formerly under sea, they were squeezed, moved, folded, and eventually elevated to an altitude

of 2,000 meters when the Australian and Pacific plates collided.

Okay, here we are.

Hamish hopes that the mountains encircling this plateau have protected the rock strata

from erosion.

These formations can give him precious evidence to support his theory.

I'm just going around here.

Just get to the head of this gully.

Okay, this is the best place to collect the samples I need.

We need samples for microfossil analysis.

Okay, this limestone is really very pure.

What should we do for our purposes?

Oh, look, got a fossil tooth.

But Hamish is under no illusions, his sampling must be extensive and extremely precise.

You know, that was a fantastic trip.

It really was.

It was much better than I thought.

We've established that there's a really thick sequence there, a fantastic story, and I can't

wait to get a couple of PhD students there crawling over that.

We want to take that sequence to bits and we're going to throw at it the latest firepower,

such as strontium isotopes.

And I think we're going to be able to solve this mystery, but it is going to take time.

Hamish must also travel to New Zealand's North Island.

Here the Pacific plate pushes underneath the Australian plate.

This tectonic movement is a constant threat to this region.

The significance of this volcanic eruption and the eruption along a considerable length,

it's most unusual, but for all that it relates to, if you like, everyday business associated

with the rifting of the crust.

If you rip open the Earth's crust, then volcanic material will reach the surface.

On the morning of June 10th, 1886, the biggest eruption in New Zealand's history occurred

here on Mount Tarawera.

It continued for four hours and killed hundreds of people.

It left a scar 17 kilometers long.

The raw energy coming from the Earth's core can be seen clearly in the ring of fire.

This is where 70% of the volcanic activity on the planet takes place.

To the west of Australia lies the Vanuatu Archipelago of 80 volcanic islands.

Like New Zealand, these islands are located at the meeting point of the Australian and

Pacific plates.

But what is happening underneath is exceptional.

Here the Australian plate is sinking under the Pacific plate.

This phenomenon, unique in the world, is occurring at the astounding rate of 15 centimeters

per year.

Three million years ago, this tectonic activity gave birth to new volcanoes like Mount Yeser,

which despite its peaceful air, is one of the world's most active volcanoes.

Phillips and Bani was born in Vanuatu.

His passion for volcanoes is also his career.

Today, he is climbing to the top of Mount Yeser to gauge the gases and the volcanic

bombs spewed out of the craters.

That's a fabulous explosion, but it's relatively small.

Sometimes the explosions are quite powerful.

These volcanic bombs lying around have been spewed out by the volcano.

For several years now, Phillipson has analyzed the gas plumes coming from the three mouths

of Mount Yeser.

The presence of gases like sulfur dioxide gives him important clues about future eruptions.

What I'm doing is measuring the concentration of gases in the plume.

I use a spectrometer that measures light absorption.

As sunlight shines through the plume, the various gases in the plume absorb light differently,

so I can identify them.

I look for sulfur dioxide and other gases.

That's a bee.

The speed of the bombs spewed by the volcano can reach 700 kilometers an hour, making close

observation extremely risky.

Wow, awesome.

Both of them at once.

That's amazing.

A and B at the same time.

Incredible.

By studying Mount Yeser, Phillipson Banny hopes to predict the volcano's future and

to understand the ongoing tectonic shifts, the same sort of movements that created the

archipelago in the first place.

Since the appearance of the first bits of the Earth's crust four billion years ago, tectonic

forces have never stopped reshaping Oceania.

But unlike this wave of rock that will never crash, Australia's future is not written in

stone.

All over Australia, scientists like Philippe Ré are studying tectonic forces hoping to

discover what lies ahead for the continent.

The Australian continent is unquestionably the most stable continent on Earth at the

present time.

But in 10 or 20 million years, we can expect a dramatic change in the geology under the

perimeter of this plate.

On the northern edge of the continent, the process has already begun, with the collision

between the Australian plate and the Asian continent.

If we were to come back here 10 or 15 million years from now, we'd see a mountain chain,

much like the Himalayas, stretching from Bangladesh in the west to southern China in the east.

We now know that Oceania has some of the oldest rocks on Earth.

It's where you can see the effects of stromatolites that oxygenize the globe.

We also know that it was the cradle of the first complex forms of life, and that later

it protected species which were wiped out everywhere else on the planet.

As always, the power of tectonics can decide the fate of continents and all those who live

on them.

God bless you.

you