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Pangaea Puzzle
What to do: Arrange the plates to match some period of time in the
past or present and then press the button to watch the continents drift.
What happens: The exhibit’s plates float on compressed air.
The real earth’s crust is made of rocky plates which float on the soft
mantle below.
HOW IT WORKS
1. The exhibit gives you an idea of what has happened to the earth’s
continents over the past 200 million years. The exhibit’s continents
drift apart on a layer of air – the real continents have ‘floated’
slowly apart on the semi-molten rock underneath the earth’s crust.
PE
EURO
NORTH
AMERICA
A
IC
FR
A
H A
T
U IC
O ER
M
A
S
AUSTRALASIA
ANTA
CA
RCTI
2. A super-continent in the geological past
was suspected by early map-makers 400
years ago – the shapes of the South
American and African coastlines on
opposite sides of the Atlantic Ocean look
as if they could have fitted together.
ATLANTIC
OCEAN
3. Alfred Wegener (Germany, 1912) showed
that the rock formations were also the
same along each coast – even the same
sort of fossils - and said the continents must
have drifted apart. He coined the name
‘Pangaea’ for the super-continent, from the
Greek words for ‘all of the earth’.
4. Continental drift was not accepted by the entire geological
community until the 1950s when it was shown that the Atlantic
Ocean was widening by a few centimetres each year as new rock
slowly wells up in the sea-bed. This is about the same speed as your
fingernails grow. The Mid-Atlantic ridge has the same shape as the
opposite coastlines!
Pangaea
- that's it all the earth!
5. We now know that the earth’s solid surface
is made up of about 12 plates which
move around as a result of convection
currents in the semi-molten rock underneath
them. Heat is being generated by natural
radioactivity deep in the earth to keep this
process of movement continuing.
6. If the continental plates are moving apart
under the oceans, they must be colliding or
sliding along each other in other places!
The India plate has
been moving north
Eurasian
under the Eurasian
plate for the past 50
million years, The
Eurasian plate has
buckled and risen to form
the Himalayas. Mount Everest
is still rising and moving
north at a few centimetres
per year.
Indian plate moves
north over millions of
years and crashes into
the Eurasian plate
PERMIAN
225 million years ago
plate
JURASSIC
135 million years ago
India
tains
moun
Plate A
PRESENT DAY
Plate B
7. The regions of the earth where the plates meet are
generally unstable, with frequent earthquakes, tsunamis
and often volcanoes. All the mountain ranges have
resulted from colliding plates, where one slides past, or
under the other and crumples it along the edge.
The mountains of Central Thailand were probably
formed at an early stage before the break-up of
Pangaea.
STUART STREET
CARDIFF
CF10 5BW
T 029 20 475 475
8. Pangaea was the most recent super-continent, breaking
up 200 million years. Geologists have been able to
identify two previous epochs when similar continental
drifts occurred. They predict with some confidence
(through computer simulations) that the present
continents will continue moving and make a new
Pangaea in about 250 million years time.
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