Download Rock - Duplin County Schools

Rocks and the Rock
Cycle
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Rock- is a solid mixture of crystals of one or
more minerals.
Every mineral- has a unique set of physical
properties, which can include color,
hardness and the way the mineral breaks.

Rocks are classified by 3 main types
(based on how they form)
igneous rock

sedimentary rock
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Metamorphic rock
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Igneous rock- forms when hot, liquid rock
or magma cools and hardens. This type
forms deep inside the Earth or at sites of
volcanic activity.

Sedimentary rock- forms when rocks are
broken down into smaller pieces that
harden into new rock. *forms on the
earths surface
• In the process of erosion, rivers move
sediment from one place to another
Rivers Transport Sediment
• Finally, the sediment is deposited in
layers
Sedimentary Rock Layers
After
compaction
and
cementation
sedimentary
rock is
formed

Metamorphic rock- forms when rock is
heated and squeezed.
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The Rock Cycle- is the continual process
by which new rock forms from old rock
material. Through the rock cycle, each
type of rock can become any other type of
rock.
The Rock Cycle
(draw cycle in your notebook)
Processes that Shape the Earth
March 20, 2012

Weathering- the process of water, ice,
wind and heat breaking down rocks. This
is important because weathering breaks
rocks into smaller pieces. These pieces
make up sediments that form sedimentary
rocks.

Erosion- process where grains of rock are
removed from their source. Erosion moves
the sediment to a place where the
sediments can collect.

Deposition- the process in which water,
ice, wind and gravity drop newly formed
sediments.
Compaction:
happens when sediments are
deeply buried, placing them
under pressure because of the
weight of overlying layers.
This squashes the grains
together more tightly.
Cementation - loose sediments are glued together
by natural glues like calcite and silica. Some glues
are stronger than others

Heat and Pressure- If the temperature and
pressure are high enough at the bottom of
the stack, the rock can change into
metamorphic rock.

Uplift- is the process by which regions of
the Earth’s crust rise to higher elevations.