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Think the rocks you see today have always existed? Think again.
New rock is forming all the time.And old rock is always breaking
down.
As Earth’s plates crash together, some rock is twisted and
squeezed to form metamorphic rock. Other rock melts to form
magma. When that magma blasts out of a volcano, new igneous
rock forms.
As time passes, wind and water wear rock down into bits of
rock and soil. Rivers and streams wash the pieces into lakes or
the ocean. Slowly, the layers build
up and form new sedimentary
rock. Rocks keep on changing in a
never-ending cycle. That’s one of
the reasons they’re so interesting
to study.
This rock in Utah is called
Delicate Arch. Wind and water
made a large hole in it.
Recycling Rock
