Page 215 - DK Children's Encyclopedia

Rock cycle SEE ALSO

▸ ▸ Earth’s surface
p.84

Rock may be very hard, but it does not last forever. ▸ ▸ Erosion p.93
It is constantly being worn away by wind, water, ▸ ▸ Inside Earth p.135
and ice. At the same time, new rock is being made ▸ ▸ Mountains p.172

at the bottom of the sea and by volcanoes. This is ▸ ▸ Rocks and
called the rock cycle. minerals p.214
▸ ▸ Volcanoes p.268

Recycled rocks
Tiny pieces of volcanic rock are
washed into the sea and settle on
the sea bed. They become buried by
new layers of rock particles that get
squashed together to form new rock.
As this new rock is buried deeper,
it gets hotter and melts to form
magma. Magma rises and cools
to form new volcanic rock.

Heated and
Breaking down
Volcanic rock is broken squashed
up by wind, rain, and ice. Cooling Any rock can be changed
Tiny particles of the Magma erupts into metamorphic rock by
broken rock are washed from volcanoes.
into the ocean by rain. It cools and hardens the heat and the weight
to form a type of of the rock above it. Slate,
rock called volcanic,
Settling or igneous, rock. which is used to make roof
Pieces of volcanic rock tiles, is a common
settle on the sea bed. metamorphic rock.
They are buried and
squashed to make
a type of rock called
sedimentary rock.

Lots of layers
Most rocks being formed
Changing Melting today are sedimentary
If sedimentary rock Deep in the Earth, where rocks. They are made from
is buried deep enough, it is extremely hot, rock tiny pieces of older rocks
it is changed by heat melts to form magma. In that build up on the sea bed
and the weight of the some places, magma rises
rock above it into to the Earth’s surface, in layers. Sandstone is a
metamorphic rock. forming volcanoes. common sedimentary rock.

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