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Since its creation, the Earth has never stopped changing.
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Colossal forces have hurled ocean floors upwards and made them into towering mountain ranges.
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Incredible collisions have created entire continents.
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These tectonic forces are still at work today.
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We see them in volcanic eruptions, earthquakes, and tsunamis.
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Tectonics sculpt our landscapes, change our climates, dry up our oceans, and can destroy life.
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The history of Oceania is like the history of the Earth itself.
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The smallest of the continents has known the best and the worst of times.
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The beginnings of life itself and also much of its destruction.
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Antarctica was attached for millions of years to Oceania's largest landmass, Australia,
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which is for now the most geologically stable place on the planet.
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Its neighbor, New Zealand, is not so lucky.
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It's in the middle of a tectonically explosive region called the Ring of Fire.
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It's all part of the endless voyage of the continents.
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Oceania is an enormous archipelago.
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It includes more than 25,000 islands, some almost as old as the Earth itself.
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Four and a half billion years ago, the Earth was a ball of liquid matter.
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There was no surface.
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Any solid ground was constantly melting back into the cauldron of the Earth's burning core.
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Scientists had long believed that the first bits of solid crust only appeared when the
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Earth had cooled down enough.
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But a recent discovery in Western Australia has turned this concept on its head.
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Simon Wilde of Curtin University of Technology and Perth has been studying crystals that
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were formed when our planet was very young.
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During the formation of the first bits of solid matter, crystallized minerals were formed.
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These minerals were soon subjected to the most intense volcanic activity in our planet's
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history.
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These ancient crystals are called zircons, and it's amazing that the ones Simon has
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found have survived until today.
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They are the oldest existing matter on Earth.
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Their structure can reveal billions of years of history.
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They are, in fact, the Earth's first historical record.
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Zircon requires a granitic rock to grow in, and so it tells us that rocks of granite composition
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were around 4.4 billion years ago, which is very interesting because previously people
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didn't believe that continental crust existed at this time, about 150 million years since
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the formation of the solar system.
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So this has really changed our view of the early Earth.
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Instead of being a hot boiling magma ocean and meteorites banging into it, what we believe
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now by 4.4, the Earth had cooled sufficiently to have continents, oceans, and some form of
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atmosphere.
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It may well be a CO2-rich atmosphere, but there was an atmosphere nonetheless.
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This is known as the Dark Ages, because there was no rock record.
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Now with the discovery of these crystals, we are actually shining light on those Dark Ages.
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The oldest existing crystal on our planet was found in Western Australia.
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In the two billion years since the formation of the Earth, small islands of crust began
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to emerge on the fiery surface of the planet.
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When these islands joined up, they formed the first pieces of continental land called
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Kratons.
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The Pilbara region of Western Australia is one of those ancient continental islands.
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It is one of the most geologically stable areas in the world.
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For billions of years, the Pilbara has protected geological treasures that would have been
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destroyed anywhere else.
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Few know the Pilbara better than Martin van Crenendonk, who's one of the few persons to
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have mapped it.
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He has spent ten years searching out the rocks that tell the history of Oceania and our planet.
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One of the greatest stories about Earth's history is how our planet changed from a very
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primitive, nasty place where it was very difficult for life to get a foothold to this modern
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world with its beautiful blue skies and oxygenated atmosphere, where life is very complex and
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abundant.
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And we've been studying those rocks over the last few years, and it turns out they have
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answers to some of these very important questions about how did life evolve and how did we get
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here.
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Martin has found astonishing things in the Pilbara.
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It was here that he discovered rock formations that may hold the key to understanding how
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life on Earth evolved from bacteria to us.
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Look at these little beauties.
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Aren't they gorgeous?
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These structures in the rocks here in front of me are called stromatolites.
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These are structures formed by colonies of living microorganisms.
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The intriguing thing about these rocks is that although they look a little bit like sedimentary
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structures you'd see on the beach, you know, normal ripples, which everybody recognizes,
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these little wavelets when the water moves over the sand, these are actually quite different.
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When you look at them in three dimensions, they are actually cone shaped.
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They actually start from a flat level and then start growing upwards, sometimes over
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tens or even hundreds of meters.
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And it's these kinds of observations which make us distinguish or help us distinguish
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between, you know, physical geology and something that's actually got the signature of early
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life.
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And don't forget, these rocks are 3.4 billion years old.
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These rocks may be inanimate today, but three and a half billion years ago they were very
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much alive.
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Although the world they lived in was nothing like the world around us today.
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At that time there was little solid ground and most of what was there was volcanic.
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The oceans were full of iron and were green.
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The sky was orange, an atmosphere of methane, ammonia and carbon monoxide.
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Not a place for human beings.
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But it all changed around a billion years ago when the stromatolites colonized the oceans.
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Two billion years ago something completely different happened.
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There was a change in the atmosphere from being rich in carbon dioxide and other gases
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like sulfur dioxide coming mostly from volcanoes to an atmosphere that was building up more
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and more oxygen.
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And oxygen is not a naturally forming free molecule.
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It's a molecule that's produced by life processes, by photosynthesis.
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Photosynthesis uses our beautiful sunlight energy and water to make body parts carbon
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and then gives off O2.
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The stromatolites transformed the atmosphere and left a record of their achievement carved
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into the rocks.
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But this is it right here.
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This is a transition where we see the real change from early earth into more modern earth.
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At this point, right in this little outcrop section behind me, these rocks pulled a story
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that's as important as the time when the dinosaurs when extinct on earth from that giant meteorite
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about 65 million years ago.
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These rocks are two and a half billion years and record the first time when an early, very
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sulfurous, gaseous kind of earth changed forever into a cool, much more modern earth.
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And that contact is right down here where you have deposits of banded iron formation
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grading up through red-colored iron-rich and gray shirts and then bang right there where
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I can put my fingernail on the contact.
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You have the change to modern earth.
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And this outcrop is probably the most exciting one I've ever seen in my 25 years of doing
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geology.
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It just encapsulates in, you know, a few tens of centimeters this fundamental change when
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earth irreversibly became modern.
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But the oxygen that was freed by the stromatolites three billion years ago did not help what
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life existed at the time.
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Quite the opposite, in fact.
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When life became more complex and started giving off oxygen, it's actually a pollutant
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to most of the earlier forms of life.
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They can't thrive with oxygen.
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Life evolved to adapt to that new chemical reality.
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And in fact, because it's harder to make life with oxygen around, life became more sophisticated.
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But that evolved slowly over time and only because they actually had to get smarter to
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live with this pollutant called oxygen around and evolve a more complex way of living.
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Those stromatolites transformed more than terrestrial life.
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They also changed the nature of the seas.
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The oxygen they gave off turned the oceans from green to red.
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Deposits of rust lay quietly on the ocean floor until huge tectonic forces thrust them
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above the surface.
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These impressive red mountains are now over a kilometer high.
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They are made up of layers of what geologists call banded iron.
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These are the remains of the massive amounts of rust that lay on the ocean floor.
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At Shark Bay on the west coast of Australia, the descendants of the ancient stromatolites
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who reigned over the world's oceans two billion years ago can still be seen.
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A drive of just a few kilometers takes Martin van Cronendonk several billion years back
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in time.
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Shark Bay is a haven for a very special type of limestone, an unusual living rock made
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up of alternating layers of crystallized minerals and blue-green algae.
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These structures are called thrombolytes and they're a type of living rock made by colonies
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of microorganisms.
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An amazing thing about them is they just grow like a tree year by year adding layer upon
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layer in these beautiful cone shapes because they're actually growing up towards the light
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to get the food energy that they need from sunlight.
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And these structures would have covered hundreds of kilometers of the sea bed because there
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was nothing to graze on them.
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They were the only living life forms and they covered the entire oceans and just pumped
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out this enormous volume of oxygen that eventually changed our planet.
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Day after day the thrombolytes at Shark Bay absorb the molecules of water surrounding
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them, decompose them and release oxygen.
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This is the same process used long ago by their ancestors, the stromatolites.
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To the northeast of Shark Bay is the Hammersley Range.
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Its massive deposits of iron have attracted prospectors who are digging into the mountains
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to expose layers of banded iron.
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If there's enough iron in these core samples, the red hills of Hammersley oxidized by ancient
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stromatolites will be gutted and stripped of their minerals.
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One company alone operates 12 mines in the region.
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The company has built entire towns and constructed a private railway over 1400 kilometers long.
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A hundred million tons of iron ore a year is taken from the Hammersley Range.
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Much of it goes to Asia to build cars and cities.
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Two and a half billion years ago the Pilbara region barely survives the violent volcanic
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activity around it.
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But as the earth cools, other small islands join Pilbara.
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This ever-widening raft of crust becomes Australia.
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As time passes all the other emerging land masses join into a single supercontinent,
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Gondwana.
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Australia finds itself welded to Antarctica.
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This collision of Australia with Antarctica occurs on Australia's south coast, yet the
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events' consequences reach as far as the middle of the Australian outback.
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Near the border of the Northern Territory in South Australia, a new mountain range rises
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up, the Peterman Mountains, with peaks as high as the Alps.
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After 550 million years of erosion, this is all that remains.
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This impressive natural wonder is Australia's most famous landmark, Ayers Rock, also known
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by its aboriginal name Uluru.
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Uluru began its existence as a huge sand dune.
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Over time the dune was cemented into a sandstone island.
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Tectonic forces lifted Uluru, turning it every which way.
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Some horizontal layers even ended up being vertical.
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Like an iceberg, only the tip of Uluru is visible.
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Although it rises to a height of 350 meters, its base extends six kilometers below the
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surface.
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In the open air, its smooth surface has prevented it from being eroded by wind and water.
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Collisions between the continents caused a number of cataclysms that transformed southern
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Australia forever.
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Jim Gilling of the South Australian Museum is both a geologist and a paleontologist.
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Jim is returning to the site of an exceptional discovery he made in the middle of Australia's
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south coast.
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At the foot of the dry Iriakara Hills, Germanist team found traces of an ocean floor that
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dried up hundreds of millions of years ago.
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When you go back 550 to 560 million years, you're looking at a shallow sea floor with
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some distance to the west and open ocean to the east.
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While it's an ocean, sediment keeps accumulating and it keeps a record of everything that's
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happened during the time of that ocean.
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But one day a sea floor will be pushed up into giant folds and pushed into mountains.
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As Gondwana formed, the landscape constantly changed.
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550 million years ago, the collision of great land masses gave rise to the Flinders Ranges,
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the largest mountain chain of South Australia.
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Over time, many of its peaks have eroded and revealed a marine world that existed more
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than 500 million years ago.
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If the Flinders Ranges had never existed, we wouldn't be here because the only way of
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actually seeing these layers would be to drill down into the earth, perhaps 500 metres, perhaps
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5000 metres, because every layer would be buried.
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It's only when these layers are buckled up and thrust through to the surface that we
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can see the frayed edges of the sedimentary layers.
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Jim and his team have dug up dozens of pieces of ancient seabed.
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Put together, this marine jigsaw puzzle takes us back 560 million years.
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We can see the undulations of a vanished sea preserved in sandstone.
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But the most extraordinary discovery is a rare trace of ancient animal life.
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OK, it's a nice surface.
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It's very reminiscent of the bed we have over on the west side.
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Mary Drozer is a professor of earth sciences at the University of California Riverside.
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She's been working with Jim for more than 10 years.
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The two researchers believe that the translucent marine animals of Idiakara mark the beginning
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of a completely new stage of life on earth.
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But if you get down on your hands and knees, you can see earth's first experiment in terms
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of an animal marine community.
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One of them had backbones.
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Preservation of soft-bodied organisms is really rare.
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So when you think about preservation of dinosaurs, what do we get?
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We get the bones.
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We don't get their soft parts.
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What we see here is we're actually getting soft-part preservation.
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It's like preserving a worm in rock.
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That's just unimaginable.
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But this was a very special window in terms of preservation.
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And what's so cool about it is that it's earth's first experiment with animal life.
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The Idiakara ecosystem brought to life by tectonic movement continues to surprise the
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researchers.
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Here's another one.
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Look at that.
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You can see in the light the first time in 560 million years.
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So if you look at something like this guy here, this is spragina.
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It's pretty common during this time.
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And when you look at it, it almost appears to have a head and a body behind.
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Now we're not sure.
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Some people have suggested that actually that's an anchor and it stood up in the seafloor.
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So we don't really understand it.
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But certainly it's got quite a developed and complex body.
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This trace fossil here you can see is just a millimeter in width.
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This would have been a small organism.
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We have no idea what made it.
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But we can see the furrows on the edge that it would have been moving through the sediment.
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So these trace fossils are really important because it's the oldest unequivocal evidence
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of bilaterians.
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And bilaterians, we are interested in bilaterians because we are bilaterians.
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We are bilaterally symmetrical.
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And we think in terms of all advanced organisms other than corals and sponges as being bilaterians.
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And it gives a bit of cushioning effect too.
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Many scientists believe that the Idiakara marine animals were our most distant cousins.
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They were annihilated by tectonic movements and environmental changes.
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But their existence on Earth lasted for more than 40 million years.
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Two hundred and fifty million years ago, about one thousand kilometers from the Flinders
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ranges, tectonics gave birth to the Blue Mountains.
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These mountains were sculpted by tectonic forces over a period of millions of years.
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The steep rock faces and deep valleys are home to several unique species including millions
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of giant kangaroos.
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They are here because of a tectonic movement that may have been the most important event
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in the history of Australia.
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Paleontologist Ann Musser works at the Australian Museum.
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As she makes her way to the bottom of this cave, she is traveling deep into the history
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of marsupials.
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She has discovered that the genolin caves in the Blue Mountains are literally marsupial
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graveyards.
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Caves are perfect traps.
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You don't really see the holes.
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If you're a kangaroo, you're hopping over the top of the surface.
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You might not see it.
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You go right down through tubes, through holes, through caves, and you can't get back out
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again.
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Oh my gosh, it's just a little young rump.
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The ancestors of these animals made an extraordinary journey.
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It is really exciting to be working on these unique Australian marsupials.
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Your ancestors came from Asia.
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150 million years ago, Asia, Antarctica, and India are all still part of the supercontinent
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of Gondwana.
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At this time, the marsupials are being driven out of Asia by mammals and dinosaurs.
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Their survival is only assured when the Antarctica Australian block breaks off from Gondwana.
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Those who miss the boarding of this tectonic life raft do not survive.
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However, not all the marsupial species are saved.
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Sometime after 50 million years, Australia, as we know it now, broke away from Antarctica,
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and it took with it that cargo of marsupials.
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And the ancient platypus and other sorts of monotremes often went, the Antiquity and
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the Rock, the animals on it were to evolve in isolation and become completely unique.
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This is the southern edge of the Niddlebar Plain, a 1200 kilometer long line of coastal
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cliffs.
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It was formed when tectonic forces tore the Australian Antarctic block apart.
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These formations of granite are echoed in Antarctica, the other side of a continental
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00:27:24,360 --> 00:27:28,680
wound that is never healed.
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After reaching the southernmost point on Earth, Antarctica became the coldest of the continents.
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Over the millennia, it was covered with thick ice which has prevented researchers from knowing
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the exact nature of the underlying mantle.
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This frozen world is larger than all the land masses of Oceania combined.
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Just to say, Antarctica was completely transformed by tectonics after its separation from its
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Australian sister.
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In Tasmania, southeast of Australia, the rift left spectacular evidence.
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00:28:17,360 --> 00:28:22,520
At Cape Pillar, the two continental plates separated in an explosion of lava that accumulated
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on the Tasmanian sedimentary floor.
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00:28:27,480 --> 00:28:36,360
Over time, the sea cooled the lava, which has remained in place ever since.
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These columns of magma resemble the pipes of the world's biggest organ and are a striking
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reminder of the separation of the two continents.
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00:28:55,040 --> 00:28:59,879
Since it broke off from Antarctica, the plate that Australia rests upon has been moving
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northward at a rapid pace, six centimeters per year, making it the fastest moving plate
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00:29:06,320 --> 00:29:11,520
on the planet.
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00:29:11,520 --> 00:29:18,280
And it's not a peaceful voyage.
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00:29:18,280 --> 00:29:27,200
North of the continent, the Australian and the Pacific plates are colliding.
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00:29:27,200 --> 00:29:32,360
The perimeter of the Pacific plate is referred to as the Ring of Fire and is one of the most
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unstable and dangerous zones on Earth.
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00:29:37,680 --> 00:29:42,080
Imagine that this is the Pacific plate, this is the Australian plate, and the two are in
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collision.
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00:29:43,520 --> 00:29:48,560
What we have is a slow-motion tectonic car crash, and the result?
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00:29:48,560 --> 00:29:54,920
Earthquakes, volcanoes, tsunami, landslides, these spectacular mountains, and more often
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00:29:54,920 --> 00:29:58,880
the knot in death and destruction.
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Geologist Hamish Campbell is fascinated by the meeting of the Australian and Pacific plates.
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A stride the rift that separates these two landmasses is New Zealand.
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00:30:25,000 --> 00:30:30,680
In New Zealand's South Island, tectonic forces created an impressive mountain range called
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00:30:30,680 --> 00:30:40,960
the Southern Alps.
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It's among the world's youngest mountain ranges, the visible face of the clash of tectonic
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plates.
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It's fantastic.
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00:30:59,239 --> 00:31:05,520
What these mountains represent is the very soft, westernmost edge of the Pacific plate,
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00:31:05,520 --> 00:31:09,719
and they are crumpling up, they're being washed against the much stronger Australian
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00:31:09,719 --> 00:31:14,919
plate, and they're going up at about a maximum of 10 millimetres a year.
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00:31:14,920 --> 00:31:20,320
And of course as fast as they're coming up, these rocks are being eroded just as a consequence
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of normal weather, rain, no ice.
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Alongside New Zealand's Southern Alps, and crossing almost the entire South Island, is
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the boundary between the Australian and Pacific plates.
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It's called the Alpine Fault.
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And it's one of the tectonic marvels of the world.
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Near this fault, earthquakes can occur at any moment.
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In fact, New Zealand has an average of 14,000 earthquakes a year.
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When the Alpine Fault shudders, it can lift the Southern Alps several metres in just a
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few seconds.
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The Alpine Fault is not the result of a frontal collision.
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The Australian and the Pacific plates are actually sliding violently against one another.
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Look at this landscape, it really is chewed up.
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The fault moves in this sense, okay?
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00:32:25,280 --> 00:32:31,560
So the Pacific side is going south, and the Australian side is going north, and it does
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00:32:31,560 --> 00:32:34,440
so, let's see.
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00:32:34,440 --> 00:32:41,040
Every time it moves, it moves sideways between 7 and 13 metres, and vertically between 2
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00:32:41,040 --> 00:32:42,040
and 4 metres.
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00:32:42,040 --> 00:32:43,800
That's a lot of movement.
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00:32:43,800 --> 00:32:47,320
And it last moved in 1717.
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00:32:47,320 --> 00:32:51,800
We think that on average it moves about every 200 to 300 years, and that's based on a lot
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00:32:51,800 --> 00:32:53,320
of research.
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00:32:53,320 --> 00:33:01,840
Now, 1717 is about 300 years ago, so it's going to move again soon in the future.
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00:33:01,840 --> 00:33:07,959
My colleagues tell me that there's more than a 35% chance of this fault moving within the
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00:33:07,959 --> 00:33:09,439
next 50 years.
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00:33:09,439 --> 00:33:11,840
So that's the forecast.
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00:33:11,840 --> 00:33:16,560
And by the way, we're standing on the Australian plate here, and that's where I'd like to
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00:33:16,560 --> 00:33:17,560
be.
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00:33:17,560 --> 00:33:26,360
It's actually more stable than the Pacific plate.
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00:33:26,360 --> 00:33:32,159
But Punakaiki, on the west coast of South Island, visitors can admire rock formations
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00:33:32,159 --> 00:33:40,040
that resemble stacks of pancakes.
351
00:33:40,040 --> 00:33:44,919
These strange layers of limestone were formed deep underwater and were then pushed up to
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00:33:44,919 --> 00:33:54,080
the surface.
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00:33:54,080 --> 00:33:59,720
These odd formations have made Hamish Campbell wonder about the geological history of his
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00:33:59,720 --> 00:34:01,600
country.
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00:34:01,600 --> 00:34:08,080
Could New Zealand have been completely submerged before being lifted above the Pacific Ocean?
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00:34:08,080 --> 00:34:12,719
Although most scientists don't agree with this hypothesis, Hamish thinks it's worthy
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00:34:12,719 --> 00:34:18,120
of discussion.
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00:34:18,120 --> 00:34:23,639
We know that a very substantial chunk of eastern Gondwana land broke away 83 million years
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00:34:23,639 --> 00:34:25,920
ago and moved off to the northeast.
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00:34:25,920 --> 00:34:28,239
And as it did so, it slowly sank.
361
00:34:28,239 --> 00:34:32,440
And it did so for 60 million years.
362
00:34:32,440 --> 00:34:37,480
Although most people are unaware of this, New Zealand is 12 times bigger than it appears
363
00:34:37,480 --> 00:34:40,759
if you count the part that's underwater.
364
00:34:40,759 --> 00:34:45,839
We call this underwater continent Zelandia.
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00:34:45,839 --> 00:34:51,239
And New Zealand is just the emergent highland part of this sunken continent.
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00:34:51,239 --> 00:34:57,240
New Zealand has literally been pushed up within the last 23 million years.
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00:34:57,240 --> 00:35:00,319
So there's a really interesting mystery to be solved here.
368
00:35:00,319 --> 00:35:05,439
And that is, could it be that New Zealand was totally submerged just 23 million years
369
00:35:05,439 --> 00:35:06,439
ago?
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00:35:06,440 --> 00:35:31,080
It's a challenging task for Hamish.
371
00:35:31,080 --> 00:35:43,040
He has to travel the country from the coast to the top of the mountains.
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00:35:43,040 --> 00:35:48,440
He's on the lookout for rock formations that have recorded his country's underwater past.
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00:35:48,440 --> 00:35:54,440
What we want to do is have a look at this limestone.
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00:35:54,440 --> 00:36:01,440
So what you want us to do is stop this down here.
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00:36:01,440 --> 00:36:11,200
Hamish is on his way to sample the sedimentary rocks of South Island.
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00:36:11,200 --> 00:36:18,040
Formerly under sea, they were squeezed, moved, folded, and eventually elevated to an altitude
377
00:36:18,040 --> 00:36:22,520
of 2,000 meters when the Australian and Pacific plates collided.
378
00:36:22,520 --> 00:36:28,240
Okay, here we are.
379
00:36:28,240 --> 00:36:32,680
Hamish hopes that the mountains encircling this plateau have protected the rock strata
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00:36:32,680 --> 00:36:35,560
from erosion.
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00:36:35,560 --> 00:36:40,120
These formations can give him precious evidence to support his theory.
382
00:36:40,120 --> 00:36:42,480
I'm just going around here.
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00:36:42,480 --> 00:36:45,640
Just get to the head of this gully.
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00:36:45,640 --> 00:36:53,160
Okay, this is the best place to collect the samples I need.
385
00:36:53,160 --> 00:37:00,240
We need samples for microfossil analysis.
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00:37:00,240 --> 00:37:08,440
Okay, this limestone is really very pure.
387
00:37:08,440 --> 00:37:15,920
What should we do for our purposes?
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00:37:15,920 --> 00:37:33,680
Oh, look, got a fossil tooth.
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00:37:33,680 --> 00:37:48,560
But Hamish is under no illusions, his sampling must be extensive and extremely precise.
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00:37:48,560 --> 00:37:50,520
You know, that was a fantastic trip.
391
00:37:50,520 --> 00:37:52,520
It really was.
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00:37:52,520 --> 00:37:54,160
It was much better than I thought.
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00:37:54,160 --> 00:37:59,799
We've established that there's a really thick sequence there, a fantastic story, and I can't
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00:37:59,799 --> 00:38:03,520
wait to get a couple of PhD students there crawling over that.
395
00:38:03,520 --> 00:38:07,560
We want to take that sequence to bits and we're going to throw at it the latest firepower,
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00:38:07,560 --> 00:38:09,720
such as strontium isotopes.
397
00:38:09,720 --> 00:38:16,759
And I think we're going to be able to solve this mystery, but it is going to take time.
398
00:38:16,759 --> 00:38:24,000
Hamish must also travel to New Zealand's North Island.
399
00:38:24,000 --> 00:38:30,800
Here the Pacific plate pushes underneath the Australian plate.
400
00:38:30,800 --> 00:38:40,880
This tectonic movement is a constant threat to this region.
401
00:38:40,880 --> 00:38:46,280
The significance of this volcanic eruption and the eruption along a considerable length,
402
00:38:46,280 --> 00:38:52,840
it's most unusual, but for all that it relates to, if you like, everyday business associated
403
00:38:52,840 --> 00:38:56,080
with the rifting of the crust.
404
00:38:56,080 --> 00:39:06,080
If you rip open the Earth's crust, then volcanic material will reach the surface.
405
00:39:06,080 --> 00:39:12,240
On the morning of June 10th, 1886, the biggest eruption in New Zealand's history occurred
406
00:39:12,240 --> 00:39:16,400
here on Mount Tarawera.
407
00:39:16,400 --> 00:39:22,799
It continued for four hours and killed hundreds of people.
408
00:39:22,800 --> 00:39:39,560
It left a scar 17 kilometers long.
409
00:39:39,560 --> 00:39:44,960
The raw energy coming from the Earth's core can be seen clearly in the ring of fire.
410
00:39:44,960 --> 00:39:56,960
This is where 70% of the volcanic activity on the planet takes place.
411
00:39:56,960 --> 00:40:03,680
To the west of Australia lies the Vanuatu Archipelago of 80 volcanic islands.
412
00:40:03,680 --> 00:40:08,360
Like New Zealand, these islands are located at the meeting point of the Australian and
413
00:40:08,360 --> 00:40:10,160
Pacific plates.
414
00:40:10,160 --> 00:40:14,160
But what is happening underneath is exceptional.
415
00:40:14,160 --> 00:40:19,080
Here the Australian plate is sinking under the Pacific plate.
416
00:40:19,080 --> 00:40:24,920
This phenomenon, unique in the world, is occurring at the astounding rate of 15 centimeters
417
00:40:24,920 --> 00:40:27,720
per year.
418
00:40:27,720 --> 00:40:34,640
Three million years ago, this tectonic activity gave birth to new volcanoes like Mount Yeser,
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00:40:34,640 --> 00:40:46,040
which despite its peaceful air, is one of the world's most active volcanoes.
420
00:40:46,040 --> 00:40:49,000
Phillips and Bani was born in Vanuatu.
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00:40:49,000 --> 00:40:53,040
His passion for volcanoes is also his career.
422
00:40:53,040 --> 00:40:59,120
Today, he is climbing to the top of Mount Yeser to gauge the gases and the volcanic
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00:40:59,120 --> 00:41:18,000
bombs spewed out of the craters.
424
00:41:18,000 --> 00:41:24,520
That's a fabulous explosion, but it's relatively small.
425
00:41:24,520 --> 00:41:27,759
Sometimes the explosions are quite powerful.
426
00:41:27,760 --> 00:41:34,040
These volcanic bombs lying around have been spewed out by the volcano.
427
00:41:34,040 --> 00:41:39,320
For several years now, Phillipson has analyzed the gas plumes coming from the three mouths
428
00:41:39,320 --> 00:41:41,280
of Mount Yeser.
429
00:41:41,280 --> 00:41:49,720
The presence of gases like sulfur dioxide gives him important clues about future eruptions.
430
00:41:49,720 --> 00:41:53,760
What I'm doing is measuring the concentration of gases in the plume.
431
00:41:53,760 --> 00:41:57,680
I use a spectrometer that measures light absorption.
432
00:41:57,680 --> 00:42:02,640
As sunlight shines through the plume, the various gases in the plume absorb light differently,
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00:42:02,640 --> 00:42:05,080
so I can identify them.
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00:42:05,080 --> 00:42:11,960
I look for sulfur dioxide and other gases.
435
00:42:11,960 --> 00:42:17,280
That's a bee.
436
00:42:17,280 --> 00:42:23,120
The speed of the bombs spewed by the volcano can reach 700 kilometers an hour, making close
437
00:42:23,120 --> 00:42:27,279
observation extremely risky.
438
00:42:27,279 --> 00:42:39,560
Wow, awesome.
439
00:42:39,560 --> 00:42:40,799
Both of them at once.
440
00:42:40,799 --> 00:42:41,799
That's amazing.
441
00:42:41,799 --> 00:42:43,319
A and B at the same time.
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00:42:43,319 --> 00:42:46,319
Incredible.
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00:42:46,319 --> 00:42:51,920
By studying Mount Yeser, Phillipson Banny hopes to predict the volcano's future and
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00:42:51,920 --> 00:42:57,280
to understand the ongoing tectonic shifts, the same sort of movements that created the
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00:42:57,280 --> 00:43:02,600
archipelago in the first place.
446
00:43:02,600 --> 00:43:08,760
Since the appearance of the first bits of the Earth's crust four billion years ago, tectonic
447
00:43:08,760 --> 00:43:13,520
forces have never stopped reshaping Oceania.
448
00:43:13,520 --> 00:43:19,920
But unlike this wave of rock that will never crash, Australia's future is not written in
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00:43:19,920 --> 00:43:23,200
stone.
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00:43:23,200 --> 00:43:29,240
All over Australia, scientists like Philippe Rรฉ are studying tectonic forces hoping to
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00:43:29,240 --> 00:43:34,920
discover what lies ahead for the continent.
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00:43:34,920 --> 00:43:40,240
The Australian continent is unquestionably the most stable continent on Earth at the
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00:43:40,240 --> 00:43:42,320
present time.
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But in 10 or 20 million years, we can expect a dramatic change in the geology under the
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00:43:47,240 --> 00:43:51,319
perimeter of this plate.
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00:43:51,319 --> 00:43:55,919
On the northern edge of the continent, the process has already begun, with the collision
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00:43:55,919 --> 00:44:02,120
between the Australian plate and the Asian continent.
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00:44:02,120 --> 00:44:07,799
If we were to come back here 10 or 15 million years from now, we'd see a mountain chain,
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00:44:07,799 --> 00:44:15,040
much like the Himalayas, stretching from Bangladesh in the west to southern China in the east.
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00:44:15,040 --> 00:44:27,800
We now know that Oceania has some of the oldest rocks on Earth.
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00:44:27,800 --> 00:44:33,320
It's where you can see the effects of stromatolites that oxygenize the globe.
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00:44:33,320 --> 00:44:38,680
We also know that it was the cradle of the first complex forms of life, and that later
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00:44:38,680 --> 00:44:44,200
it protected species which were wiped out everywhere else on the planet.
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00:44:44,200 --> 00:44:51,080
As always, the power of tectonics can decide the fate of continents and all those who live
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00:44:51,080 --> 00:44:52,080
on them.
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00:44:52,080 --> 00:45:19,000
God bless you.
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you
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