Al final del Cretácico, hace 66 millones de años, el impacto de un asteroide gigantesco en Chicxulub, en la costa de México, oscureció los cielos y enfrió el planeta, matando a todos los dinosaurios salvo las aves.
#ExtinciónMasiva, #ImpactoChicxulub, #Dinosaurios
etiquetas: Cretácico, asteroide, extinción, dinosaurios, aves, impacto, Chicxulub, cambio climático, historia de la Tierra, paleontología
#ExtinciónMasiva, #ImpactoChicxulub, #Dinosaurios
etiquetas: Cretácico, asteroide, extinción, dinosaurios, aves, impacto, Chicxulub, cambio climático, historia de la Tierra, paleontología
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FunTranscript
00:00The death of dinosaurs is a mystery lost in the mist of time.
00:12This extraordinary murder scene is the only place in the world where we can see remains
00:17of creatures that died in that great extinction.
00:20And in the heart of it is hidden one of the greatest mysteries of science.
00:29We know that dinosaurs died from the impact of a great asteroid against the Earth.
00:35But how could it kill not only the dinosaurs of the place, but all those who inhabited
00:41the world?
00:47We have accessed exclusively an extraordinary expedition to delve into the crater of the
00:52asteroid.
00:53And what they are discovering is much more incredible than Hollywood could ever imagine.
01:05The asteroid triggered an unstoppable and lethal chain of events.
01:13And now, thanks to the discoveries of this expedition, we can reveal exactly what happened
01:19the day the dinosaurs died.
01:29To understand what happened, we start here, in the Visti Valdez lands, New Mexico.
01:35To know what the world was like the day before the asteroid hit the Earth.
01:41The paleontologists Steve Brussate and Tom Williamson are looking for dinosaur fossils.
01:45A stream.
01:52That looks like a bone.
01:54Is it a turtle?
01:55This is one of the richest areas in fossils in the world.
01:59Yes, it's a bone.
02:00Okay.
02:01Come on, look at that.
02:03It has a layer of bone.
02:05Many times we travel through these wasteland lands looking for things that protrude between
02:09the rocks.
02:10And that's always the first clue.
02:12This one's really sticking out.
02:15We can tell from the shape that it's part of the backbone of a dinosaur.
02:20It's the backbone of a dinosaur with horns.
02:24It's probably a Pentaceratops, which means five-horned face.
02:29Two horns on the eyes, one on the nose, and two on the cheeks.
02:34The Triceratops has three horns on its face.
02:37This one had two more, five in total.
02:39So it was an extravagant body of a dinosaur.
02:46Before they extract the fossil, Steve and Tom have to wrap it in plaster, hoping that
02:5266 million years later, it won't break when they take it out.
02:55Yeah.
02:56Ready?
02:57Yeah.
02:58Okay.
02:59There it is.
03:00There it is.
03:01Good.
03:02Look at that.
03:04It's not bad.
03:09It's wonderful.
03:10So, there it is, on the other side.
03:15This is part of the backbone of Pentaceratops and it would have gone, more or less, like
03:26this.
03:27With fossils like this, we can get a better idea of what these powerful beasts looked
03:33and even how they lived.
03:39They were the main herbivores of the place.
03:43This whole area is absolutely littered with these cows of the Cretaceous.
03:49They were everywhere in this landscape.
03:52The Pentaceratops was a creature that wandered through North America in the late Cretaceous
03:58during the last 10 million lives of the dinosaurs.
04:03At that time, the landscape was far from what it is today.
04:09During those 10 million years, this was a kind of jungle, to give us an idea.
04:14There was dense vegetation, large trees, lush forests and rivers flowing through the jungles.
04:21Food was abundant for herbivores, who in turn were prey to the most terrifying carnivores of all.
04:32These herbivores were fed by one of the most famous dinosaurs of all, the Tyrannosaurus.
04:39So there was Tyrannosaurus Rex here, in New Mexico.
04:43But there is also the grandfather of this one, the Vistageversor,
04:47which had about 60 of these very sharp teeth,
04:52and he used them to grind the bones of these herbivorous dinosaurs.
05:02The dinosaurs dominated the land for 160 million years.
05:08But not only here, in what we now call New Mexico, but all over the planet.
05:24That's what the world was like 66 million years ago.
05:29That's what the situation was when things really changed.
05:33This was the landscape that the Earth offered the day before the death of the dinosaurs,
05:38while the asteroid was advancing through space.
05:4566 million years ago, our world was very different.
05:49The sea level was higher and the continents were smaller.
05:54But the main difference was that the dinosaurs dominated the planet.
05:59Until one day, everything changed.
06:04An asteroid hit the Earth in the Gulf of Mexico.
06:09The pressure was about the same as in the center of the Earth.
06:13The temperatures rose tens of thousands of degrees.
06:17Bad news for the dinosaurs.
06:20But the most amazing thing of all is that not only the dinosaurs of the area died,
06:25but all those who inhabited the planet.
06:29We're looking at an Armageddon.
06:32We have a lot of dead bodies.
06:35And that has always been the great mystery.
06:38How could a bad day in Mexico become a massive extinction worldwide?
06:44The geologist Søn Gallik hopes to solve the mystery once and for all.
06:50Søn is part of an international group of scientists
06:55who yearn to discover what happened when that huge space rock
06:59pierced the Earth's surface.
07:02Søn is one of the most important geologists in the world.
07:07Søn is part of an international group of scientists
07:12who yearn to discover what happened when that huge space rock
07:17pierced the Earth 66 million years ago.
07:21And how did it annihilate the dinosaurs?
07:25A mission that begins in a much more recent asteroid crater here in Arizona.
07:30This crater was created by the impact of an asteroid
07:35that is about a mile across.
07:39It's actually quite small. It's basically simply a ball-shaped crater.
07:44By studying the shape of the crater and the layers of rock,
07:49geologists can find forensic data on the moment of impact
07:54and the magnitude of the explosion.
07:57Everything above the red line that we see there
08:01is material that was buried.
08:04It was elevated, and now we see it upside down,
08:07like a pile of broken material.
08:10The effects of the impact of this asteroid would be relatively local.
08:16So it comes in at about 26,000 miles per hour,
08:20and 10 kilometers away from here we have a fireball,
08:2420 kilometers away we have the expansive wave,
08:27and it's at 40 kilometers away we have hurricane winds.
08:30But it wasn't just a horrible day for the north of Arizona.
08:35It was a horrible day for the mammoths in the area,
08:39but not a global extinction.
08:42The asteroid that annihilated the dinosaurs, 15 kilometers wide,
08:47left a crater 200 kilometers in diameter.
08:53However, despite its size, it's very hard to tell.
08:58It's so well hidden that it wasn't discovered until 1990 here,
09:03in the Gulf of Mexico.
09:05It's called Chicxulub.
09:07This is the Gulf of Mexico, and the impact crater is here.
09:11But the reason it wasn't discovered is because it's buried.
09:14So it's not going to be obvious anywhere on the surface
09:17that you're in a crater,
09:19because it was buried with 66 million years of limestone.
09:26Hidden under 600 meters of limestone,
09:29the Chicxulub crater is not only huge,
09:32but it has features that elevate it to a new category of supercraters.
09:38Chicxulub is one of the largest impact craters there is.
09:41It's not like the one we have behind us,
09:44which has a hollow shape and is overcome by two types of craters.
09:48This one is a little bit bigger,
09:50we would see a certain rebound, a central elevation,
09:53and if it were a little bit bigger,
09:55we would see a little bit more of a rebound,
09:57it's like it's crumbling out,
09:59in a rocky ring called the peak ring.
10:02This peak ring can only be found in the craters
10:05caused by the major impacts,
10:07and it's its rocks that give us the best clues
10:10about the moment of impact.
10:14Sony and his colleagues will go into the heart of the asteroid crater,
10:18under the sea, in the Gulf of Mexico.
10:22The goal of our next project is to drill that peak ring
10:26just here off shore, in the sea,
10:28where it's the shallowest area,
10:30and we're just going to drill it,
10:32and we're just going to pick up samples of it.
10:35And when they do,
10:36those rocks will reveal what happened in the minutes,
10:39hours, and days after the impact,
10:42and they will solve the riddle of how the dinosaurs died.
10:51After 20 million years of planning,
10:54and with an international team of scientists from 11 countries,
10:58the drilling of this ambitious project
11:00to investigate the Chicxulub crater is about to begin.
11:06Right now, beneath the drilling platform,
11:09and beneath our ship as well,
11:11is the Chicxulub peak ring.
11:13It's buried by 66 million years of rock
11:17We've picked this area because it's the closest
11:20the ring is to the current seabed.
11:22The pillars are taller than I thought they would be.
11:25Yeah.
11:26Yeah.
11:27Woo-hoo!
11:28Let's go!
11:31All right.
11:32Even so,
11:33the team will have to go through 600 metres of limestone
11:37before they can reach the peak.
11:39It's going to be a long journey.
11:41It's going to be a long journey.
11:43It's going to be a long journey.
11:45600 metres of limestone before they reach the crater.
11:50For eight weeks, the drillers will be working 24 hours a day.
11:56We run two shifts,
11:57from midnight to noon,
11:58and from noon to midnight.
12:02Here we go.
12:15This is the drill.
12:16Each one of these little nodules is an industrial diamond.
12:19We're going to try and get 100 metres out of this.
12:26It's a great effort on a human scale.
12:28People are very excited about science.
12:32And that's what scientific dreams are made of.
12:41It's a unique expedition.
12:43No one has ever drilled the peak ring of an asteroid crater,
12:50because Chicxulub is the only one on Earth whose ring is still intact.
12:57The next closest one is in the moon's hidden face.
13:03The coordinator and initiator of the expedition is Jo Morgan.
13:07I've been very excited about this for years,
13:09so to see that it's already a reality,
13:11that scares me a lot.
13:13We've worked so hard to get to this point
13:16that we want some pretty good results.
13:22As they go deeper into the marine bed,
13:24the team extracts rock samples three metres in length.
13:32This is the first core or complete witness of the expedition.
13:36We're literally extracting cylindrical rock samples
13:39three metres in length,
13:40and as we go further down in the hole,
13:43we go further to the moment of impact,
13:46about 66 million years ago.
13:52As soon as a core comes up on deck,
13:54we give a small sample of the material.
13:56We take it back to the lab,
13:58and we determine its age in less than five minutes
14:01after it has appeared on deck.
14:04In a set of portable cabins,
14:06which they affectionately call their main street,
14:09the scientists study each core with ink when they extract it.
14:14I just got some sweet images.
14:15Look at this crystal.
14:17It's the core catcher material,
14:19seen with a microscope.
14:22We've been using the so-called acoustic imagery,
14:26which offers us an image of the inside of the hole,
14:30and some of them,
14:31especially of the subsequent layers to the impact,
14:34are beautiful.
14:37When the team begins to extract cores from the crater itself,
14:41they will give them clues about the asteroid,
14:44its size, its speed,
14:46the force of the explosion,
14:48and the chain of events that led to the end of the dinosaur reign.
14:59But first, they will extract core after core
15:02from the layers of limestone.
15:05And they will inspect each sample,
15:07looking for any sign of change
15:09that indicates that they are approaching the crater.
15:22One of the key mysteries for the team
15:25is how an asteroid that fell in the Gulf of Mexico
15:28killed all the dinosaurs in the world.
15:32Here in New Jersey,
15:34paleontologist Ken Lacobara
15:36believes he has found some victims of that fateful day.
15:42Animals killed by the asteroid,
15:44despite being 2,700 kilometers away.
15:50As we go down this road,
15:52we go back millions of years in time,
15:55and down at the bottom of the crater,
15:57we're right at the bottom,
15:59like 66 million years ago.
16:11So this is all underwater.
16:18If you look up at the top of the trees
16:20about 70 feet high,
16:22we can imagine the level of the ocean
16:2466 million years ago.
16:28And at the bottom of the quarry,
16:30Ken has dived into the bed of that ancient sea.
16:34Oh, that's beautiful.
16:36I can hear it getting a little bit crunchy here.
16:40And he has unearthed an amazing and fatal scenario
16:43in a thin layer of ancient sand.
16:46We are in the boundary,
16:48right here, at the end of the dinosaur era.
16:51We have a fatal scenario here.
16:55Look at that beautiful clam in that layer.
16:58It lived 66 million years ago,
17:01and died right at the time
17:03dinosaurs died,
17:05and 75% of the species of the Earth died.
17:10In this layer of bones from his quarry,
17:13Ken has found an amazing amount
17:16and variety of animals that died together.
17:19We find the remains of Mosasaurus.
17:22Mosasaurus were giant sea lizards
17:24the size of a bus.
17:26They had fins on the ends,
17:28and a six-foot-long jaw
17:30filled with sharp teeth like this one,
17:32and it would fit down here along
17:34a score of other teeth.
17:42Now, the top part of the throat
17:44had another pair of jaws,
17:46and these teeth went back,
17:48keeping their prey from escaping out.
17:51This thing was a sea monster.
18:09This beautiful fossil is from
18:11an ancient marine crocodile.
18:13They have a very long snout
18:15that goes out like this,
18:17full of teeth,
18:19and these animals sit at the bottom
18:21of the sea with their mouths open,
18:23waiting for something to swim in,
18:25and bam!
18:27Ambush predators.
18:29As you can see, the skeleton is articulated,
18:31which means that their bones
18:33are still connected as they were in life.
18:37This is a clue to what happened that day.
18:40They died here,
18:42and shortly after they would be buried.
18:46As clues are revealed,
18:48it becomes evident
18:50the mass massacre that took place here.
18:54In a small corner of the quarry,
18:56Ken and his team discovered
18:58a slaughterhouse
19:00where the fossils rest
19:02as they were found.
19:06Five years of excavation,
19:0825,000 fossils.
19:11We have a lot of dead bodies.
19:13We're looking at a slaughterhouse.
19:16These animals lived together
19:18and died together suddenly.
19:20They were quickly buried,
19:22and now we have before us
19:24the fatal scenario
19:26that occurred 66 million years ago.
19:30From the sands of saber-toothed
19:32to the crocodiles,
19:34snails and turtles,
19:36nothing escaped the slaughter.
19:38By the different species
19:40that we find here,
19:42we see that it was a widespread catastrophe.
19:48Ken believes that these are
19:50the first victims of the collision
19:52to be discovered,
19:56and he thinks he has found
19:58the evidence to prove it.
20:00What you see here,
20:02these things quite tiny,
20:04are crystal spherules.
20:06When an asteroid hits the earth,
20:08the rocks melt,
20:10but when they cool down so quickly,
20:12they can't turn back into rocks,
20:14but they turn into glass,
20:16and from the sky,
20:18small drops of melted glass
20:20begin to rain down,
20:22which we find in this layer of bones,
20:24in the layer of mass death
20:26that we see here.
20:28But we have more.
20:30In addition to spherules,
20:32we also find crushed quartz,
20:34tiny grains of sand
20:36with peculiar fracture lines.
20:38The only ways we know
20:40of forming crushed quartz
20:42is either a nuclear detonation
20:44or the impact of an asteroid,
20:46and I'm pretty sure
20:48that dinosaurs had nuclear weapons.
20:50More and more evidence
20:52indicates that these animals
20:54were victims of the meteorite impact,
20:56the first to be found
20:58all over the world.
21:00Well, at the fossil quarry,
21:02in the layer of bones,
21:04we have quartz,
21:06we have spherules,
21:08and we have the bodies.
21:10I think that everything points
21:12to the fact that we are
21:14looking at beings
21:16who perished in the crucial
21:18and calamitous day
21:20that killed the dinosaurs
21:22and shaped up the modern world
21:24as we know it.
21:26If we could take the asteroid
21:28to trial,
21:30these tests would suffice
21:32to condemn it.
21:34But the question remains the same.
21:36How could the impact of an asteroid
21:38in the Gulf of Mexico,
21:40more than 3,000 kilometers away,
21:42cause such carnage
21:44in New Jersey?
21:46How did a local event
21:48turn into a global devastation?
21:54And the mystery grows even more
21:56considering that,
21:58in relation to our planet,
22:00there is no evidence
22:02that the asteroid was tiny.
22:08So, if the Earth was the size
22:10of this ball of balls,
22:12the asteroid that hit us
22:14would have been the size
22:16of just one of these grains of sand.
22:18So it didn't move the Earth
22:20on its axis,
22:22like a grain of sand
22:24couldn't move this ball
22:26or destroy it.
22:28But it did cause 75% of the Earth's life
22:30or at least the non-flying ones.
22:32So, how was that possible?
22:34Well, we think it fell
22:36at a really bad point.
22:40We return to the Gulf of Mexico
22:42where the perforation continues.
22:44The expedition
22:46hopes to reach the crater
22:48at any moment
22:50and reach the rocks
22:52that will unravel the mystery
22:54of what made that global annihilation possible.
22:56Let me look at this
22:58in the microscope.
23:00I would say
23:0264 million and a half
23:04or 64 million and a half
23:06or 63 million and a half years.
23:08Wow.
23:10So this was E4,
23:12which is 53 million,
23:14and now where are we?
23:1663.
23:1810 million.
23:20Yes, that's a good estimate,
23:2210 million years in three meters.
23:24In three meters.
23:26A big leap in time.
23:28This huge leap in time
23:30tells them
23:32that they could reach the crater
23:34at any moment.
23:36And three weeks after the perforation?
23:38As you go down,
23:40there's more and more of that.
23:42It's got a greenish tone.
23:44There's evidence of an event
23:46on a scale that no one expected.
23:48We've now had four cores of sand
23:50getting more and more rough
23:52and I think the only process
23:54that we've seen anything like that
23:56is a tsunami.
23:58And the fact that we're now 12 meters thick
24:00makes it one of the biggest,
24:02if not the largest,
24:04tsunami deposit ever discovered.
24:06It was a much bigger
24:08violence than expected.
24:10A big tsunami deposit.
24:12A big tsunami cake.
24:14With bits of glass.
24:18And just under the proof
24:20of a huge tsunami,
24:22something changes again.
24:24Look at the color of the matrix.
24:26It goes from green to red.
24:28It looks like a melt.
24:30Yeah, it looks like a melt.
24:32It looks like a giant melt sample.
24:34This rock is not easy to melt,
24:36but the enormous pressure
24:38from the impact did it.
24:40It's a sign that the team
24:42has reached the crater.
24:44We are now completely
24:46in the impact rocks.
24:48It's really easy to see
24:50because it's granite,
24:52and we can see these large
24:54leopard-like spots.
24:56This granite was dragged
24:58up here from the depths
25:00of the earth's crust.
25:02This was formed at the time
25:04when the dinosaurs died.
25:06This rock tumble is a proof
25:08of the inconceivable force
25:10of the impact.
25:12That's this guy.
25:14During the remaining five weeks,
25:16the team crosses another
25:18700 meters of the crater's
25:20peak ring.
25:24I don't think it could have gone
25:26any better.
25:28We've got the peak ring,
25:30so we have about 700 meters
25:32of material, so we're happy.
25:34I'll not forget about this place.
25:42Son, Joe, and the team
25:44set off with their precious load.
25:48In it, the clues about
25:50how the dinosaurs died
25:52are hidden.
26:00After four months of
26:02perforation, the expedition
26:04team meets in Bremen, Germany,
26:06to analyze their precious
26:08columns of rock.
26:10Within these cores are
26:12the evidence that will reveal
26:14minute by minute what happened
26:16during the impact of the asteroid
26:18and what it meant for the dinosaurs.
26:22Unraveling the secret
26:24is a mastodontic task.
26:26More than 800 meters of rock
26:28must be carefully divided,
26:30examined, and photographed.
26:32And what they tell
26:34is an impressive story
26:36of violence.
26:40This core,
26:42superior to the crater,
26:44is the usual size
26:46of a marine bed.
26:48Layer upon layer of rocks
26:50of a similar look,
26:52slowly accumulated.
26:54These three meters of limestone
26:56took 10 million years
26:58to accumulate,
27:00but the impact of the asteroid
27:02affected the geology
27:04much faster.
27:06The next 600 meters of rock
27:08were deposited in a single day
27:10as the force of the impact
27:12crushed the crust of the earth
27:14like clay,
27:16leaving layers of granite,
27:18sand, and melted rock
27:20in a chaotic massif.
27:24What we have here is granite,
27:26like the one we have
27:28in the kitchen,
27:30only this one comes from
27:32the crater of Chicxulub
27:34and has been subjected
27:36to a lot of pressure,
27:38a stressed granite.
27:40This is the proof that explains
27:42what happened in the first seconds
27:44of the impact.
27:46Here I have an example
27:48of what normal granite would look like.
27:50We can see how hard it is,
27:52and that if we cut it,
27:54we could make a funnel with it.
27:56It's a very solid material.
27:58But this, on the other hand,
28:00has completely changed
28:02due to the pressure waves
28:04that went through it
28:06after the impact.
28:08It's very fragile
28:10because it has been very stressed,
28:12very damaged.
28:14Originally, all this was
28:16about 10 kilometers deep
28:18in the crust,
28:20but that process
28:22raised it and crumbled
28:24outwards,
28:26forming an entire ring
28:28of mountains of this granite.
28:30And the amazing thing
28:32is that it all happened
28:34in a matter of minutes.
28:36Let's take a closer look
28:38at the impact of Chicxulub.
28:42A rocky body
28:44about 15 kilometers in diameter
28:46was approaching the Earth
28:48at about 60,000 kilometers per hour.
28:52Seen from the planet,
28:54it would have gone from being
28:56a dot in the sky
28:58to hitting it in just seconds.
29:00Too fast
29:02to see it approach.
29:06It fell into the coastal waters
29:08of northern Mexico.
29:12The asteroid evaporated
29:14instantly,
29:16and the rocks of the Earth's crust
29:18disintegrated by the impact,
29:20which created a hole
29:22about 30 kilometers deep
29:24and 100 in diameter,
29:26and expelled the buried granite
29:28upwards.
29:34The pulverized rock
29:36flowed like a liquid,
29:38erupting in mountains
29:40higher than the Himalayas
29:42before collapsing
29:44in a matter of minutes,
29:46forming that ring of peaks
29:48so characteristic
29:50of the greatest impacts.
29:54The Earth was shaken,
29:56and finally,
29:5866 million years later,
30:00the story of those violent
30:02ten minutes has been revealed.
30:06In this core is the proof
30:08of what happened next.
30:10This one is so unique.
30:12It contains a mixture of things
30:14that normally you would never
30:16find near each other,
30:18which is pretty amazing.
30:20If we look at the pieces of rock,
30:22we see ones with angles,
30:24with corners,
30:26and others that are pretty rounded.
30:34Now, something that rounded
30:36had to be in the water.
30:42It was so hot
30:44that the sea evaporated,
30:46leaving a big hole
30:48about 200 kilometers in diameter.
30:54The ocean had been pushed away,
30:56and the ocean's got to come back.
31:00And it's so hot,
31:02we turned it right into steam,
31:04and we have this mixture
31:06of so rounded stuff,
31:08rounded stuff together
31:10to make this crazy pile
31:12look like a fake granite pile.
31:16But the big question is,
31:18what effect did this have
31:20on the dinosaurs?
31:22To answer that,
31:24the team needs to estimate
31:26the size of the explosion,
31:28and the only way to do that
31:30is to look at the largest explosions
31:32made by humans.
31:44This is the Nevada Test Site,
31:46the most bombarded place on Earth.
31:48928 of the largest nuclear explosions
31:50ever made were made here.
31:52Explosions that can help
31:54physicists Mark Moslow
31:56and David Dearborn
31:58to calculate the size
32:00of the asteroid explosion.
32:04Nice fireplace.
32:06Oh yeah, with the double windows,
32:08it frames where it all happened.
32:10Yeah, I can see the direction
32:12from which the explosion came.
32:14This house belonged
32:16to the people of Doom Town,
32:18built to study
32:20the effects of a nuclear explosion.
32:22It survived a detonation
32:24known as Apple II
32:26in May 1955.
32:38The blast must have come
32:40all the way here,
32:42those pieces of glass
32:44would have been crushed
32:46by a wind of about 150 km per hour.
32:48The windows would disappear, yes.
32:50They would explode, for sure.
32:52And I see that this chimney
32:54has a crack.
32:56The upper part of the chimney
32:58has rotated.
33:00And it hasn't just rotated,
33:02it's moved.
33:04Most of the damage
33:06was done by the fireball,
33:08and the heat it generated,
33:10and the houses that were
33:12even closer didn't survive.
33:16Tests like this are very important.
33:18Those of us who work
33:20on asteroid impacts,
33:22we naturally started to compare
33:24them to nuclear explosions,
33:26because they're similar phenomena.
33:28The investigators had high-speed cameras,
33:30meters to determine
33:32the intensity of the shock wave,
33:34the expansive wave in the air.
33:40A particular phenomenon
33:42found in nuclear explosions
33:44and asteroid impacts
33:46is the fourth shock wave.
33:48The pressure of the shock wave
33:50from a nuclear explosion
33:52is so high
33:54that it actually
33:56surpasses the force of a crystal.
34:02So it squeezes the crystal.
34:04When the crystal is squeezed,
34:06it has to crack,
34:08and that's what shocked quartz is.
34:10We saw the chimney
34:12and the way it was fractured.
34:16Part of it was rotated.
34:18That's what happens
34:20to the internal structure
34:22of the crystals.
34:26You need the force
34:28of a nuclear explosion
34:30to break the internal structure
34:32of quartz.
34:34The fracture lines
34:36of quartz.
34:42But this is nothing
34:44compared to the pressure
34:46unleashed in Chicxulub.
34:56Hidden in the layers of the core,
34:58the team finds their own
35:00shocked quartz.
35:06This is a piece of shocked quartz
35:08that we extracted recently
35:10from Chicxulub,
35:12seen under the microscope.
35:14We have many lines on it.
35:16The more lines we see
35:18in different directions,
35:20the greater the pressure
35:22it was subjected to,
35:24and we find pieces like this
35:26in all the impact rocks.
35:28Based on the study
35:30of nuclear explosions,
35:32Joe has been able to calibrate
35:34the same hydrocodes
35:36used to model nuclear explosions.
35:38In fact, we have stolen those codes
35:40and we have applied them
35:42to our simulations
35:44of formation of impact craters.
35:46This event was equivalent
35:48to 10 billion Hiroshima.
35:50It was huge,
35:52the largest in the last 100 million years,
35:54the most catastrophic
35:56that has happened to the Earth.
35:58It was as if
36:0010 billion atomic bombs
36:02exploded.
36:04It generated a fireball
36:06that reached
36:0810,000 degrees Celsius.
36:10In addition to a wave
36:12of pressure
36:14that reduced it all to pieces.
36:22All being alive
36:24a thousand kilometers away,
36:26would die instantly.
36:30And that only
36:32in the first couple of minutes.
36:38So,
36:40what would be the effect
36:42of the explosion on dinosaurs
36:44like those that inhabited
36:46the Valdian lands of New Mexico?
36:50Standing out here,
36:52it's really hard for me
36:54to imagine what it would have been
36:56like 66 million years ago
36:58when everything changed.
37:02So, in that day,
37:04this whole area here
37:06would have been filled
37:08with dinosaurs.
37:10And then, about 2,000 kilometers
37:12in this direction
37:14to the southeast,
37:16the asteroid hit the Earth.
37:18And very quickly,
37:20the dinosaurs would realize
37:22that something was wrong.
37:24Because there would have been
37:26an enormous mushroom-shaped
37:28glowing red cloud
37:30that would have filled up
37:32much of the sky here.
37:34But that wouldn't have really
37:36affected the dinosaurs.
37:38They would have seen it,
37:40but it wouldn't have hurt them.
37:42Now, thousands of kilometers
37:44closer to the impact,
37:46their cousins down in Texas
37:48would have been burnt,
37:50but all over the world,
37:52most of the dinosaurs
37:54were still alive.
37:56The sea monsters
37:58of Ken La Covarra
38:00in New Jersey
38:02were still swimming happily.
38:04But not for long.
38:08A deadly and unstoppable
38:10chain reaction had unraveled.
38:21A particular nucleus
38:23of the impact crater
38:25reveals how a bad day
38:27in the Gulf of Mexico
38:29ended up becoming a global disaster
38:31for the dinosaurs.
38:35Okay, so you're now
38:37on the top of the boundary layer.
38:39And this is the famous
38:4140 core, which is so exciting.
38:43If we look at it,
38:45we see some dark layers
38:47and we think they might be
38:49from an earthquake
38:51or something in the depths
38:53of the earth that was raised.
38:55But the important thing
38:57is not just what's on the layers,
38:59but the journey
39:01that the material undertook.
39:03We think that they probably
39:05took a couple of laps
39:07around the planet
39:09before raining back down
39:11to the crater.
39:13It's proof of a huge ejection
39:15of pulverized rocks
39:18and it's this ejection
39:20that turned a local disaster
39:22into a global massacre.
39:26When the asteroid hit the ground,
39:28vaporized,
39:30there was a huge column
39:32of rock vapor
39:34that expanded upward
39:36at a very high speed
39:38and outward to the rest of the planet.
39:40A blanket of dust and vapor
39:42spread rapidly from the impact area.
39:44This was hot gas
39:46of rock
39:48and as it went up,
39:50it cooled and formed
39:52these spheres
39:54the size of a grain of sand.
39:58When these things re-entered
40:00the atmosphere,
40:02they got hot again
40:04by the friction of the air
40:06like shooting stars.
40:08But if you were standing up,
40:10you'd have seen
40:12an incredible number
40:14of shooting stars
40:16up to the point
40:18of not distinguishing them
40:20individually.
40:22You'd have seen a huge layer
40:24of hot lava
40:26going far above you
40:28in all directions.
40:30It wouldn't fall on you
40:32because it would be
40:34about 60 kilometers
40:36from the ground.
40:38But that hot lava
40:40would emit an energy
40:42and the temperatures
40:44on the ground
40:46rose several hundred degrees
40:48causing terrible fires
40:50in its wake.
40:52This is not a normal fire.
40:54This fire was started everywhere
40:56which causes a massive fire
40:58and the mass fire
41:00can be much higher
41:02than a normal fire.
41:04All the leaves on the ground
41:06were on fire
41:08and the leaves
41:10were on fire.
41:12Hurricane winds
41:14were blowing towards the fire,
41:16raising the flames
41:18and they consumed everything.
41:22Therefore,
41:24this steam did not take long
41:26to spread all over the planet.
41:28In just a couple of hours
41:30it would have reached the borders
41:32of the Earth.
41:40In the Valdia lands of New Mexico
41:42the dinosaurs had escaped
41:44from the initial explosion
41:46but that mantle of fatality
41:48was advancing rapidly towards them.
41:52In just 11 minutes
41:54the sky began to darken.
42:02It wasn't really a case of
42:04fire in the sky
42:06bringing it down to the heavens
42:08but a case of all of that stuff
42:10heating up the atmosphere
42:12and turning it into a giant radiator.
42:18For several minutes
42:20the lava in the sky emitted
42:22a strong heat.
42:26On the ground
42:28it would have been as hot
42:30as a pizza oven
42:32so that destroyed a lot of dinosaurs
42:34but it also started to cause fires
42:36In a matter of two hours
42:38all of this landscape
42:40had completely changed.
42:42Most of the dinosaurs
42:44had disappeared
42:46and a new world began to emerge.
42:50The disaster spread
42:52all over the globe
42:56but there were areas
42:58where the dinosaurs
43:00could have escaped from the fires
43:02and it didn't explain
43:04why the sea
43:06didn't catch fire.
43:10However,
43:12they would have a devastating final blow
43:14and the proof is not present
43:16in the nucleus
43:18but absent in them.
43:20A particular mineral of sulphate.
43:26This is gypsum
43:28at the time of the impact
43:30in Yucatan there was gypsum
43:32that contained sulphates.
43:34Taking into account
43:36that the asteroid landed
43:38in shallow waters
43:40large amounts of gypsum
43:42would be expected in the crater.
43:44If we look at the recovered nucleus
43:46of the crater of Chicxulub
43:48we don't find any gypsum.
43:50There is nothing.
43:52It should be full of gypsum
43:54but it's not
43:56which means that
43:58in the moment of the impact
44:00the gypsum that was present
44:02in the target
44:04went to the atmosphere.
44:06This is perhaps
44:08the biggest revelation of all.
44:10The team has discovered
44:12that the amount of this harmful sulphate
44:14in the atmosphere
44:16must have been huge,
44:18much larger than imagined.
44:20This material evaporated
44:22by the impact
44:24and released into the atmosphere
44:26was the killer.
44:28This amount of powder
44:30would be enough
44:32for the surviving dinosaurs.
44:36The spread of remains
44:38blocked the sun's rays
44:40and the light went out.
44:48After the fires were consumed
44:50the darkness suddenly
44:52darkened.
44:54There would probably be
44:56we can imagine
44:58the last tyrannosaurs
45:00trying to hunt something
45:02but that would be very difficult.
45:04So if they survived the fire
45:06they probably would have starved to death.
45:08Because there was no light
45:10it was very cold
45:12and after a few days
45:14the temperature had dropped
45:16below freezing point.
45:18The global temperatures
45:20plummeted 10 degrees centigrade
45:22in a matter of days
45:24and photosynthesis stopped
45:26both on land and at sea.
45:30All that debris
45:32and all the sulphates
45:34in the atmosphere
45:36blocked the sun
45:38and the food chain
45:40broke.
45:42A chain that in the ocean
45:44was very short.
45:46In less than a month
45:48they went from plankton
45:50to super predators.
45:52If you were as big as a mosasaur
45:54you would be one of the first
45:56to disappear.
46:00It was this nuclear winter
46:02that caused the massive
46:04slaughter of Ken's quarry.
46:08The green landscapes
46:10turned grey.
46:14With nothing to eat
46:16all over the planet
46:18the dinosaurs had
46:20no food.
46:28After many months
46:30of darkness
46:32the sun's light
46:34gradually returned to the surface
46:36and with it a new development.
46:38The surviving creatures
46:40had inherited the earth.
46:44What I have on the tip of my finger
46:46is a lower tooth
46:48of a mesodma.
46:50It was a little guy
46:52about the size of a mouse.
46:58This is a tiny
47:00but very few species
47:02that survived
47:04to the global devastation.
47:06It's a blade-like tooth
47:08and it was able to feed
47:10on insects and seeds
47:12so it did not depend
47:14on photosynthesis.
47:16The death of the dinosaurs
47:18allowed these small
47:20survivors to grow
47:22and the mammals evolved
47:24quickly to take over the planet.
47:26These rocks are the sediments
47:28that have accumulated
47:30for hundreds of thousands of years
47:32since the extinction of the dinosaurs
47:34and here we find the first mammals.
47:36In fact, the mammals
47:38originated almost at the same time
47:40as the dinosaurs
47:42and they lived throughout
47:44the dinosaurs but they remained
47:46relatively small.
47:48It wasn't until the dinosaurs
47:50were extinct that mammals
47:52began to diversify
47:54and become large animals.
47:56This is the jaw
47:58of a mammal that had a head
48:00like the head of a wolf.
48:06It just was a paradise
48:08for these new animals.
48:11Without the mammals
48:13that survived that extinction
48:15we wouldn't be here
48:17because among those groups
48:19of survivors were our ancestors.
48:21They were among the very few mammals
48:23to survive to their extinction.
48:28It was a stroke of luck
48:30that paved the way
48:32for our own evolution.
48:34If the asteroid had hit
48:36just a few seconds before or after,
48:38the story would have been
48:40very different.
48:42The point where it hit
48:44was particularly disastrous
48:46for life.
48:48Lots of this volatile material
48:50was released into the atmosphere
48:52and if it had just hit
48:54at a slightly different time
48:56with the rotation of the Earth
48:58it could have hit the Atlantic
49:00or the Pacific Ocean.
49:02And if it hit one of those
49:04instead of Mexico,
49:06that event might not have been
49:08significant enough to actually
49:10end the age of dinosaurs.
49:13In fact, it's possible
49:15that we wouldn't have
49:17taken over the planet.
49:36Transcription by ESO. Translation by —
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