Download Sedimentary Rocks

Sedimentary
Rocks
Written by Denise Ulrich,
DSD Writing Committee
©Davis School District Farmington, Utah 2012-2013
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The Big Sandwich
Sedimentary rock is made of bits and
pieces of rock. The pieces have been broken
off of other rocks over time by wind, water
or ice. These pieces of rock are called
sediments. The sediment is moved from place
to place and settles into layers.
The layers become pressed
together over millions of years.
It’s kind of like nature’s own
giant sandwich!
Layers of sedimentary rock
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How Sedimentary Rock Is Formed
Wind, water or ice can wear down a large
rock or side of a mountain, creating
sediments. This process is called weathering.
Then running water, such as streams or
rivers, rushes by and picks up the sediments.
The sediments are carried to a new place
such as the bottom of a lake or ocean. As the
sediments settle on the floor of the lake or
ocean, a layer is created.
Water carries and leaves sediments in
layers
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Over millions and millions of years, new
and different layers of sediments are
brought to the same spot in the same way.
The layers of sediments stack on top of each
other. The pieces of rock are pressed
together by the weight from the sea and the
many layers above. This is how sedimentary
rock is formed.
A rock formation in Utah made from
sedimentary rock
How People Use Sedimentary Rocks
You may use sedimentary rock and not
even know it. Coal is a sedimentary rock that
is burned to create energy for electricity to
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light our homes and schools. Sedimentary
rocks, such as sandstone
or limestone, are used as
stones for large
buildings. Clay is mixed
with sand and used to
Coal
make bricks for houses
and other buildings. Limestone is also used in
our roads, and is cooked to make cement for
sidewalks and driveways. During winter
storms, people use rock salt to break down
the ice on roads and walkways.
Sandstone
Limestone
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Glossary
sand- loose grains made up of broken pieces
of rock
sedimentary rock- rock formed in layers
from sediment
sediments- pieces of rock or sand that are
deposited by wind, water, or ice
weathering- the breaking down of rocks into
smaller pieces called sediments
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