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Making mountains
The Himalayas started to form
50 million years ago, when two
moving plates collided. The
mountains are still growing!
Cracked crust
Earth’s top layer is
made up of giant
pieces called “plates”.
These fit together a
bit like a jigsaw, but
they’re constantly
moving. Volcanoes
and earthquakes often
happen in the weak
spots where plates move
against each other.
Volcanoes
Volcanoes are
openings in the
Earth’s crust.
Sometimes magma
(melted rock) from
just beneath the
crust bursts through
these openings as a
volcanic eruption.
Lots of ash and dust
shoot out too.
Earth’s structure
10 million years ago
135 million years ago
200 million years ago
San
Andreas
Fault
The Himalayas.
Drifting continents
The world hasn’t always
looked like it does now.
Millions of years ago, all the
land was joined together.
Slowly, it broke up and the
continents drifted apart.
Earthquakes often
occur along the San
Andreas Fault.
Fault lines
Earthquakes happen
when “plates” rub
against each other.
Active
volcanoes
