Planet Earth hundreds of millions of years in the future.
intergalactic explorers return to their home planet
in search of signs of ancient civilizations
they find a planet that has changed
beyond recognition
gone are the familiar continents that we
know today
instead they find a giant landmass
with huge mountain ranges, massive frozen snow fields, and glaciers.
the once thriving metropolis they seek
has disappeared.
a few broken remnants are all that remain
crushed and buried beneath tons of rock.
could this be a future vision of Earth? Naked Science asks
what forces could create such a
bleak and barren world?
and investigates how the awesome power
of colliding continents
shapes and reshapes our planet in
an endless cycle of construction and
destruction.
Our world - the Earth
from space its easy to see the
distinctive pattern of land
that makes up the continent's North
America, South America,
Africa, Antarctica, Europe, Asia,
and Australia. Giant landmasses
separated by
oceans that stabilize the environment
with hospitable weather patterns
suitable for civilization and cities to
evolve and prosper.
Now imagine our planet ravaged by storm
force winds
subjected to extremes of temperature,
giant freezes,
heat waves and droughts.  A world where
cities
are crushed and destroyed.  Where Africa
tramples New York under foot
and London freezes at the North Pole
the geological future of New York is
going to be rather traumatic. North
America
and Europe are going to collide with one
another
The world as we know it will be
unrecognizable.
This is not a portrait of the earth
after a devastating global disaster
this is how nature will shape our planet
many millions of years
in the future. This incredible remodeling
is just part of the natural cycle that has 
shaped the earth
for the last four billion years, and will
continue to do so
until the Sun finally destroys its
surface
once and for all.
Today our continents may seem solid,
safe and forever fixed in place but they
are none of those things
these great landmasses are constantly
on the move
speed up the last few billion years
and one can see the continents sailing
across the globe
powerful forces deep within the planet
rip the continents apart and then smash
them together
in ever-changing cycle of death and
rebirth
oceans disappear mountains crumble
and rise again.  Landmasses form
and reform. Colliding continents are the
mightiest force
on earth.  When we look at the history
planet earth we see that it is full of change
change is part of nature and this
change continues today and will continue
into the future
To understand how the continents shape our world
we must first travel back in time to the
very birth of the earth
4.5 billion years ago
the earth is created from the debris
left over from the formation of the Sun
dust and debris collide in clump together
once these clumps grow into objects about
half a mile in diameter
they create enough gravity to attract
more material
slowly these clumps grow into as many as
20 planets
as these new planets orbit the Sun they
begin to collide
one collision with the planet Thea, which
creates the moon,
obliterates the surface of the earth.
The energy from the collision makes the
Earth incredibly hot
at around eleven thousand degrees
Fahrenheit
it's more than seven times hotter than
the inside of a cremation furnace
Earth is a massive molten ball of boiling
Lava.
This is primeval hell.  Where thousands of
asteroids and comets
bombard our world.
But deep within the planet a process starts
that will lead to the first land.
The heaviest elements, lead and nickel,
sink down to the center of the Earth
to form a molten core. The lighter
elements,
including oxygen and silicon, rise to the
surface
where they erupt in volcanoes of molten
rock.  Slowly,
the earth's surface cools. Molten lava
solidifies to form patches of crust.
The seeds of the first continents.
But even as the first land is born, it
faces a battle to survive
...that we were being bombarded by a large
number
of asteroids very early in the history of the planet.  So there's a lot of
dynamic change from being walloped by
giant impacts disturbing things...
Geology professor Sam Boring
is an expert in early earth and the genesis
of the continents.
...when we had an early crust is an
interesting question. I suspect we've had
an early crust from day one.
The question is how long was that preserved?
When the earth was being bombarded
constantly by asteroids
the chance of preserving any small chunk
of that crust was very low.
The relentless bombardment destroys the
new planet's crust
almost as soon as it forms. This
recycling on the surface
continues for many millions of years. But as the
flux of asteroids began to wain, and as
the earth matured a little bit, I suspect
the early crust lasted a little bit
longer.
Eventually the barrage from asteroid
impacts slows down.
The surface of the earth continues to
cool but the earth is missing one vital ingredient
oceans
Where earth got its water is has been a
controversial topic over the years
and I think most people now think that
many meteoritic bodies actually
contain quite a lot a water.
Water carried by meteors and asteroids may form the oceans
that surround the first continents.
The earth -  4.4 billion years ago
our planet is now 150 million years old
and the first permanent land masses have
formed. They're not like the seven
instantly recognizable continents of
today. They are just small rafts of rock
floating on the mantle.
But now a type of rock appears on the Earth's surface that will form the nucleus 
of future continents.
A rock buoyant enough not to sink into
the bowels of the earth
granite - in South Africa
in the Kaapvaal region southwest of
Johannesburg
geologists examine ancient granite that
has survived the ravages of time
these are the ancient remains
of what some people consider to be the
first true continent
we're looking at relics, the remnants of
the first continental nuclei.  This is
one the oldest but certainly
the best preserved continental
nucleus in the world. 
Geologist Alex Kisters studies how granite formed the first continents.
The rocks here are so important
because they are remarkably well-preserved
much better than anywhere on earth.  And
that allows us actually to
study processes that were involved in
the formation
of these earth crustal rocks.  Kisters
is collecting samples to date
the age of the granite
I'll drill these little rock cores, taking them out 
and sending them off to the lab to
be dated
Dating rocks is a complex process
because over long periods of time
the minerals can break down and reform
into new rocks
scientists look for an ingredient of
rock
that is tough enough to withstand the
test of time
the answer is zircon - a crystal that is
made inside molten rock as it solidifies
even if the rock is destroyed the zircons are durable enough to survive
Zircon is an incredibly interesting
mineral and it incorporates uranium
and excludes lead and that sets us up to
have basically nature's time capsule
to illustrate this process imagine that
this hour glass is a newly formed zircon crystal
sand in the top represents uranium, the
sand in the bottom
represents lead.  Over millions of years
the uranium in the zircon on turns into
lead.
measuring the relative proportions of
sand in the top and bottom of the glass
reveals how much time has passed.
Uranium's relentless decay into lead
gives us a natural clock. Using this
technique
geologist date this granite at three
and a half billion years old
this makes it some of the oldest rock on
the planet
these rocks make up a major part of what
is known
as the Kaapvaal Craton. A craton is an
ancient raft of rock
light enough to float on the mantle and
around which
a continent will grow.  Ancient cratons
have also been found in the heart
of the Australian
and North American continents. The
Craton here
in Kaapvaal in South Africa stretches
for 463 thousand square miles
it's almost twice the size Texas
without granite, the Craton, and modern
continental crust
wouldn't exist. Granite forms when
minerals in the crust melt
then react with water, cool, and
crystallize.
Because it is made of lighter minerals,
granite is less dense than
other rock in the mantle, so it floats on
the surface
and mixes with other rocks to form
rafts of land.
the Kaapvaal craton is not totally
built from granite.
The oldest rocks here
are these amazing pillow lavas exposed
along the Comite river
three and a half billion years ago they
form under the sea
as lava emerges from an underwater
volcanic vent
upon contact with water the lava
immediately gains a solid crust which
then cracks
and oozes additional large blobs called
pillows
the rocks off amongst the oldest
that we know.  Basically identical to your
pillows lavas that you see on the recent
ocean floor in settings like Hawaii.
The Comite pillow lavas
begin their life on the ocean floor but are
pushed up out of the sea
to form part of a continent.  But where
did the granite come from?
To create it, you need the right mix of
minerals
A new theory suggests that life itself
may have provided the missing
ingredients. It may sound like an outlandish idea
but there's some evidence that living
organisms that use photosynthesis
appeared around the same time that the
continent's began to grow
3.8 billion years ago
scientists suggests that early organisms - microbes
help speed up the breakdown of
rock emerging at the earth's crust
over hundreds and thousands of years
this rock breaks down into new minerals
which sink back into the mantle
deep below the surface may heat up
and form granitic magma.  The magma rises
into the proto-continent, freezes, and
forms huge solid rafts of granite.
Now stabilized,
the craton begins to grow, forming new
baby continents
But cratons are not the only factors at
work
more powerful forces are building up
deep within the planet
forces that have the power to rip apart
landmasses
and smash them together, changing the
face of the planet forever
4.5 billion years ago, the earth forms
for many years it has been bombarded by asteroids and meteors
slowly the molten planet cools and
small land masses form around cratons of granite rock
massive forces from deep within the
planet rip apart
and smash the small proto-continents
together
as they grow into the large land masses
we see today
the surface of the Earth, the crust, is
made up a giant jigsaw
of interlocking pieces called tectonic
plates
the separate plates themselves sit on the
mantle
the layer between the crust and the
Earth's core
although the mantle is made rock
the heat and pressure deep down mean
it's flexible enough
to allow the plates above to move up
to several inches a year
evidence for the theory of continental
drift was first proposed in 1912
by German scientist Alfred Wagner
he noticed that identical fossils were
discovered oceans away from each other
paleontologist professor Mark McMenamin
Mount Holyoke College in Massachusetts
is an expert in fossil records.  Wagner
noted
that a freshwater organism cannot cross
a salty sea
and so if you find the fossils of a
freshwater organisms or a land creature
on two continents that are now greatly
separated by distance
they must once have been closer together. By identifying like fossils on different continents 
scientists can map which continents were
joined in the past
the fossil distributions will tell us where fossils occur
and how the continents must've been
juxtaposed
fossils that are identical but occurring
in very different parts of the world
imply that the continents have drifted. 
When he first proposed his theory of continental drift
Wagner was laughed at. The idea that
continents could actually move
was considered preposterous. The problem
was
He didn't know how the continents moved.
The missing mechanism wasn't discovered.
until the 1960's
Plate tectonics is powered by heat
Plate tectonics is being
largely driven by the fact that the
interior of the earth is much hotter than the surface
the temperature at the center of
the core
is 10,000 degrees Fahrenheit.  It's as hot
as the outer parts the Sun
much of the heat is left over from the collisions
and massive bombardment during the early
days of the earth
The rest comes from radioactive decay
of heavy elements in the core.  Heat escaping from the core
creates convection currents in the next
layer of the Earth -
the mantle -  the process
is like a lava lamp - where heat from the
bulb at the bottom
creates convection currents in the oil,
pushing the synthetic lava upward
the heat melts part of the mantle
and sends plumes of magma, molten rock,
rising to the surface
it rises between cracks in the plates
creating new rock that pushes the plates apart
I think that plate tectonics is virtually
inescapable on this planet
it's an exceedingly efficient way to
cool the interior of the earth
this formation at new rock splits apart
and separates the plates and the
continent's sitting on them
today the majority of this new rock
forms under the sea, creating vast
interconnected volcanic mountain ranges
that extend through all the major oceans of the world
one range can clearly be seen at the
bottom of the Atlantic Ocean
along the mid-Atlantic ridge. It
stretches more than 12,000 miles
on the sub-antarctic to the Arctic. It
comes to the surface in a few places
Iceland was created from volcanic lava
bubbling up at the junction between the
North American
and Eurasian plates. It's one of the few
places on earth
that one can actually see continents
being pushed apart
We are watching here, geological structures that you cannot
really watch anywhere else it's like a
big text book of geology
this is where the earth's crust is being
made 
professor of geophysics at the
University Iceland monitors the
mid-ocean ridge
where the continental plates are
splitting apart. The region Iceland
is almost three miles wide, on one side
is the North American plate
on the other side the Eurasian Plate
the rift here grows as new rock forms at
its center
pushing North America and Europe away
from each other
the Atlantic Ocean widens and the two
continents drift apart
eventually the Atlantic could become as
big as the Pacific
to measure how fast they're splitting
Inerson intakes global positioning
system readings
at specific points along the plate
margin.  He put on them right on top of
the point and then we can calculate
the exact position of this point in the world with respect to the center of the earth
Although the ridge appears calm
and there's no magma rising to the
surface, Inerson's measurements
show that the two continents are
drifting apart by around and inch a year
so by the end of the century Europe and
America
will be almost eight feet further apart
The movement in Iceland is typical of the
process is shaping the continents
since their birth 4.4 billion years ago
it's part of the great cycle of the
Earth's continents
the new crust created at the mid-ocean ridge
moves away, cools, and eventually
sinks back into the earth. When the first
proto-continents formed
there were several interconnecting
tectonic plates
constantly bumping and grinding against
each other
pushing the new land over the planet.
Today the earth has over a dozen plates some colliding together
some moving apart, they are powerful
enough to move a continent the size of
North America
over 3,000 miles in 200 million years
that's fifteen miles every million years
The earth 3.4 billion years ago
and plate tectonics pushes the proto-continents together
they combine to form ever larger tracts
of land
scientists suggest that cratons
combined with other cratons
to form a supercontinent - a huge
continuous stretch of land
it's called Vaalbara. Scientists are
unsure if its exact shape or size
as only a few pieces, like the craton
in South Africa 
still remain
but Vaalbara's days are numbered. A
rising plume of heat
is growing beneath it.  It's about to
rip the world's first supercontinent
into pieces.
2.7 billion years ago Vaalbara
the world's first super continent still
dominates the planet
but plate tectonics powered by heat
from the earth's core
is about to split it apart
rock is a good insulator. When a continent
gets very large
the rock traps heat beneath it
as it gets hotter and hotter a plume of
superheated magma
builds up beneath the giant continental
mass
the temperature continues to rise
and pressure in the mantle increases
eventually
the crust can no longer contain the
pressure and the hot lava breaks through
ripping the land apart
you can see this process happening today
in Africa
heat from the earth's core is ripping
the continent apart
a giant rift valley runs from the Red
Sea
down to Mozambique.  Giant cracks are opening up in the land
volcanoes like Kilimanjaro
mark spots where molten rock have risen
to the surface in the past
in 10 million years, the eastern half of
the continent
will have split away
the molten lava trapped beneath the
Giant Super continent of Vaalbara
eventually smashes through the surface
rock, the continent ruptures into several
smaller pieces
these bits of land sail across the earth
but nobody knows what happens to them or what the plan it looks like this time
the earth is entering the dark ages
it is over two and a half billion years
since it was formed
it will be over a billion years before
another super continent forms
the earth is entering a deadly cycle
of destruction and rebirth
the theory of continental drift suggests
that we go through cyclic phases
of continental dispersion and then
continental collision
and the continents then seem to move
apart from one another
and then collide with one another over
maybe a hundred
million year or more time scale 
when a large continent splits apart the
separate pieces travel away from each other
pushed by the creation of new land at
the ridge between plates
because the earth has a constant
surface area
the same amount of land created must be
absorbed into the earth
this process happens at subduction zones
at the junctions of plates - at a subduction
zone
crust dives down into the mantle to be
melted to form new rock
when the plate subducts into the
earth's it brings two pieces of land together
when they collide a new super
continent starts to form
it is now 1.1 billion years ago on our
timeline
and the next known super continent has
formed
its name is Rodinia and it holds almost
all of the Continental rock on the
surface of the earth - still no one knows
exactly what it looked like
but at its heart is an area that will
eventually become North America
350 million years later
the cycle of annihilation and creation
starts again
as the buildup of heat beneath the
surface of the earth tears Rodinia
apart. When Rodinia splits
it forms several smaller continents that
for millions of years drift apart
and then drift back together again to
form Gondwana
a supercontinent in the southern
hemisphere eventually after several
hundred million years
Gondwana slowly splits apart - plate
tectonics
push the land back together to create
the world's last super continent
it's a huge land mass known as Pangea
all the continents we know today
are here, joined together.  Geologists are
able to plot the continent's relative positions
because $350 million years ago there are
numerous species on Earth
each living in distinct regions - this
specimen that I have right here
is the first trilobite by there was ever
described from
what is now the United States - it is
exactly the same type of trilobite
that occurs on the other side of the
Atlantic Ocean in North Africa
so we know then that the trilobites
in the Old and New Worlds must've been
close together because they are so
closely related
the fossil record show that North
America and Europe
rest next to one another - the land where
New York now sits
is next to Morocco in North Africa
the Atlantic Ocean does not exist
on the east coast of South America nestles against the western coast in Africa
while Australia, India and Antarctica
are joined to the south east of Africa
if we want to look at a picture of the
world 250 million years ago you're going to look
at a World in which
a four-footed creature could walk from
one end to this land mass to the other
Pangea is one giant continuous landmass
it not only makes the world look very
different it also has a dramatic effect on climate
because much of the land is located far
from the sea
the climate the interior changes
radically from season to season
it gets very hot in the summertime and
extremely cold in the winter
you don't have the moderating influence
in the ocean
that we have today so it's a very
different world
and it's a world that I'm in some ways
is is harsher
and less hospitable at least to life on
land
it's thought that the climate change
caused by Pangea's formation
may have played a role in one of the
largest mass extinctions on earth
this event known as the promo
Triassic mass extinction
wipes out about ninety percent of all
life on earth
it's been called the mother of all mass
extinctions
I we consider that the formation a Pangea
with it's climate worsening
effects to be a contributing factor,
however
and not the sole cause of the mass
extinction
250 million years ago
and the supercontinent of Pangea is
breaking up
the continents we know and recognize
today
begin to take shape
over the next tens of millions of years,
South America drifts away from Africa
North America away from Europe
Australia splits off from Antarctica and
heads north
to warmer climes
positions of our continents are becoming
familiar, although their
distinguishable features are not
the world's vast mountain ranges, the
Alps, and Himalayas
and it's great valleys, like the Grand
Canyon,
are yet to form.  They will emerge
out of one of the biggest battles in nature,
the battle
between colliding continents
Earth - 100 million years ago
the Continental map of the modern world
is gradually becoming recognizable
but a battle is still raging between the
continents
that will change the face of our world
forever
and create some of the most
extraordinary geological features
on the planet. As the continents
moves slowly across the earth,
crust and rock is dragged back down into
the earth
at subduction zones between the
tectonic plates
but when continets collided the
plate junctions
sometimes there is a battle for
supremacy 
if neither plate will submit
and drop down to be consumed by the
mantle, then both the continents slowly
smash and grind into each other
these pinch points of continental
collision
build mountains
the Alps are the largest mountain range
in Europe
higher than the Rockies the Alps stretch
from France in the west
through Italy, Switzerland, and Austria
to Slovenia in the east
their formation is a direct result in the
continental collision
between Africa and Europe. The story of
the Alps begins when the African plate
breaks away from the South American
plate - it starts moving
toward Europe. Without the plate movement, there wouldn't be any mountain on this planet
professor Gerard Stamfli in Lausanne
University in Switzerland
studies the processes that built the
Alps
the African and Eurasian plates
start to move toward each other, trapping
the third smaller
Iberian plate between them - the three
plates collide
the Eurasian Plate is pushed downward
into the mantle
chopping off the Iberian plate -  the
Thethys Sea
begins to close
as the Eurasian Plate grinds underneath
the African Plate
it pushes the Thethys seafloor, and part
of the Iberian plate
600 miles north and many thousands of
feet
into the air. Rocks that started life on the
bottom of the ocean
end up at the top of the Alps. But whether
I think to imagine that if you're on top 
of the Matterhorn, you're
actually standing on top of Africa
for geologists, Africa starts in the Alps
over the next 100 million years, the
continent's continue to smash together
new mountain ranges start forming around
the globe, the largest
the himalayas form as the Indian plate
charges northward to the Eurasian Plate
it moves a 2 inches per year lining up
a head-on collision
the movement of the Indian plate leads
to a clash between two giant continents
and creates some of the highest
structures ever to exist on earth
the incredible power of continental drift
not only builds mountains, it also sculpts
one of the world's most recognizable landmarks
the Grand Canyon in Arizona
the Grand Canyon is a great scar on
the surface of the earth
geologist Ron Blakey has been studying
the canyon for over 30 years
it's just a wonderful place to come face
to face with planet Earth
the Grand Canyon is 277 miles long
and up to 18 miles wide
at its deepest, it stretches down for
over a mile
the gorge exposes the interior of the
North American continent
it's like looking through the pages of
the book, each layer
tells a story about the past
one of the really neat things about the Grand Canyon
is as we go up the walls of the Grand Canyon it's just like going through a time machine
layer upon layer of rock reveal the
geological history of North America
from present-day to two billion years
ago
the deeper you go
the older the rocks
by studying the layers, Blakey can piece
together the history of the canyon
he finds some of the most interesting
evidence
at the very top - fossils of ocean creatures
wow, this bed's the jackpot here
what we have is a extraordinary example
of a Permian seafloor.  The most important
thing it tells us with respect to the Grand Canyon
if this area had to be near sea level
when these rocks formed
now at seven thousand feet above sea
level on the rim of the Grand Canyon
so something had to happen - either the
sea had to fall seven thousand feet
and we're pretty sure that didn't happen
or this landscape had to be up-lifted
7,000 feet - we're pretty sure that happened
250 million years ago
the canyon starts to form as a result of
a collision
between the Pacific and North American
plates - they collide with such force
the North American plate thrusts more
than
two miles upward - what was once seabed
rises over a period of 15 million years
to form a vast plateau - far above sea
level
it stays that way for millions of years,
until it is transformed by water erosion
6 million years ago, several hundred
miles south of the canyon
plea movements open up the Gulf of
California to the sea
for the first time small streams in the
Rocky Mountains
could empty into the ocean.  So if we're
starting a stream at
14,000 feet in the Rocky Mountains, and
carving down to sea level
and the Grand Canyon just happens to be
in the way, the grand canyon's gonna get cut out
these streams merged to form what is now
called the Colorado River
it cuts down through the land heading to
the gulf of California
it took a river to carve the canyon
the water has carved down through the rocks
layer by layer by layer, removing
material
out of the canyon and leaving the great
void that sits behind me
the Grand Canyon is a testament to the
awesome power of the continents
in shaping our world
back on our journey, tracing the birth
and death for the continents
it is now 20 million years ago -
two-and-a-half thousand miles south of the grand canyon
another plate collision is about to take
place
the map of the modern world
is almost complete
this time water flowing freely between
the Pacific and Atlantic oceans
still separates North and South America - over many millions of years
the Pacific plate begins sliding under
the Caribbean plate
the pressure causes underwater volcanoes
to erupt
some explode with such ferocity
that they create a range of small
islands between North and South America
over the next 17 million years
ocean currents deposit sediment in gaps
between these new islands
gradually the sediment builds up and
compresses
to form land bridges between the islands
three million years ago, the Isthmus of
Panama
a narrow strip of land finally joins
North and South America
it separates the Pacific and Atlantic
oceans
the flow of water between the two stops
and ocean currents must take new routes
this causes yet another change in the
climate of our planet
it changes the movement of warm seas
around the globe
disrupting weather patterns - possibly
pushing the planet
into an Ice Age. Many species are wiped
out
the continents, as we know them today,
are formed
creating the nice hospitable environment
for human civilization to evolve and
thrive on planet Earth
but how long will it last?
the forces that power plate tectonics
are still active and will tear our
continents apart once again
they will build a new world - one that may
trigger another mass extinction
and push humanity to the brink of
annihilation
a view from space reveals
Earth's continents as we know them today.
There are seven total
but some are separated by a political divide
rather than a geographical one
Africa-Eurasia is a super continent
comprising
Africa, Europe and Asia - it stretches from
the Siberian plateau in Russia
to the Cape of Good Hope in South Africa
A spectacular route across three
continents incorporating dramatic
climate change
vivid scenery and diverse cultures 
however, Africa and Eurasia isn't the only super-continent on the planet
because the Panama isthmus links North and South America together
they too can be thought of as one vast
landmass
and if the Bering Strait between Russia
and Alaska were to freeze over
it would be possible to walk from Cape
Horn in South America
to the Cape of Good Hope in South Africa
A journey of around 25,000 miles - but this won't always be possible
for powerful forces deep below the surface
continue to send the continents
hurtling across the globe
the process that started at their birth -
4.4 billion years ago
and one which will continue long into
the future
what we are observing at the moment is only a snapshot of
the earth's global cycle that has been undergoing for the last 4.5 billion years
and will be undergoing even if we're not
around anymore
the global continental cycle has another
impact on our world
it causes many natural disasters
plate movement creates stress points
which lead to volcanic eruptions
as continents split apart - instability at
the plate junctions
causes earthquakes that rip apart whole
communities
this one - on October 8th, 2005
in Pakistan ruled Kashmir - killed nearly
75,000 people
and left up to three million homeless -
and when plates subduct into the earth
their death throes produce devastating waves
the 2004 Indonesian tsunami
is just one demonstration of a terrifying power
unleashed when plates move
such natural disasters are part of the
Continental cycle
and they're not going to stop
plates moving is something we have to live
with - there's nothing we can do about it
its going to happen, they're going to be
big earthquakes in California there's going
to be a lot of damage
there's going to be a loss of life
in recent years it seems as though
natural disasters
powered by the movement of the
continents have been on the rise
but what we are witnessing is an
increase
in awareness rather than an increase in
the number or severity of natural disasters
I think what we're really seeing
here is a very raised consciousness
of the public with instant communication
abilities
much more publicity is given to volcanic
eruptions and earthquakes
we are observers to only a very short
period in the life of the earth
if we could monitor earthquakes and
volcanic activity
caused by plate movements over millions
of years
we would see a very different picture
when you look at something over 10 years
you might have ten major earthquakes
the next 10 years you might have not have
any
but that's not significant it just is
related to the short period of time that
you're making the observation
when you start looking at hundreds,
thousands and millions of years
all that averages out. It's impossible to
predict exactly when the next disaster
will occur
but it is possible to predict where it
will happen
the plate boundaries
map the location of earthquakes and
volcanoes
and they lineup with the cracks between plates - plot where these plates will move over the
next tens of millions of years
and the future looks bleak for many of
the world's cities
So what will our world look like in the
future?
50 million years from now
the Atlantic Ocean will widen pushing
New York further away from North Africa
meanwhile in the southern hemisphere
Australia will be on a collision course
with Southeast Asia
and Europe, Africa will head north
closing the Mediterranean Sea - a new
mountain range will form were Italy
and Greece once stood
known as the Mediterranean mountains
they will be as big as the Himalayas
extending from Spain across southern
Europe - from the Middle East
and into Asia.  100 million years
in the future and the power of
continental movements
will render the surface of the earth
unrecognizable - the Atlantic Ocean will
continue to widen
but a subduction zone will form along
its western shoreline
the first sign of it can be seen today in
the Caribbean
the Puerto Rico Trench - this trench will
grow north
and south along the east coast of North and South America
this vast subduction zone
will consume the Atlantic Ocean - dragging Europe and Africa
back toward the Americas
250 million years in the future
intergalactic explorers returning to
their home planet
will find a world very different to the
one in their records
there will no longer be seven continents
but one gigantic landmass containing
most of the land on earth
they could find it a barren frozen world
the Explorers search for the remains
of our cities
but when Europe and America collide,
any cities along the coastlines will be
gradually destroyed
the geological future of New York
is going to be rather tramatic
in the long term New York is going to
be at the site of a continental collision
North America and Europe are going to
collide with one another and produce a
distinctive sheet of rocks which will
eventually be crumpled between the two
continents as they collide
New York in its neighbors will be
crushed and buried beneath the surface
leaving no more than a few remains - in
the future
geologists will be able to find remains
of New York City
trapped in the rocks themselves - either
buildings
or plastic bottles or old autos
and their parts, all these things will be
incorporated into the fossil record
and will be recognizable to a future
geologist who knows
what she or he is looking for
because if its similarities to past
supercontinents
this future landmass is called
Pangea Ultima - the final Pangea
nearly all the landmasses in the world
will be joined together
Pangea Ultima will probably experience
climate extremes
freezing winters and scorching summers
this deadly weapon could have devastating effects on
all life on Earth
the implications for the human race are
interesting to speculate about
certainly the disposition of the
continents over time will affect
Earth's climate and that will in turn
have an influence on which organisms survive
which go extinct and could be a factor
in future mass extinctions
the world we know is inching slowly
toward its own destruction
the processes that shape the surface of
the earth are never going to change
we're going to have earthquakes, we're
going to have volcanoes, we're going to
have tsunamis and hurricanes
regardless of whether humans inhabit the
planet
and so, the planet will always be here
probably
plate tectonics will operate for the
foreseeable few hundred million years
the question is whether humans will be
here to witness it or not
But even Pangea Ultima
might not be the end of the story - the
forces that created it
may eventually rip it apart and start
the cycle of death and rebirth again
but by then
the impact of colliding continents could
have been too much for our species
with our cities destroyed and the
climate severe
we may have already left I planet
in search of a safer home
