Download The Rock Cycle

The Rock Cycle
What drives it?
What is a rock?
 An aggregate (combination) of
minerals.
 There are 3 main categories of rock
known as “rock types”.
Rock Types
 Igneous
 Sedimentary
 Metamorphic
Rock Formation
Is a sequence of events that may involve one or all of
the following processes:
-formation
-destruction
-alteration
-reformation
 The original state of all rocks on earth is Magma.
Rock Evolution
Created by the following geological processes:
 generation and movement of magma
 weathering
 erosion
 transportation
 deposition of sediment
 metamorphism of preexisting rocks.
Magma
 Requires Heat
 Melted rock
 Found under the
earth’s crust
 Known as “lava”
above the earth’s crust
 Crystallizes to form
Igneous Rocks
Igneous Rocks
 Requires crystallization
 Intrusive - crystallized
inside the earth
 Extrusive - crystallized
outside the earth (see
picture)
 Can be eroded to
produce sediment
Sediment
 Produced by the erosion
of any type of rock.
 Rock is eroded by
mechanical (rain, wind,
freezing/thawing) and
chemical (dissolution)
processes.
 Sediment is deposited
and layered to form
Sedimentary Rocks
Sedimentary Rocks
 Requires the transport,
deposition, compaction and
lithification of sediment.
 Can be melted to form
magma.
 Can be eroded to form
sediment.
 Can be metamorphosed
through intense heat &
pressure.
Heat and Pressure
 Any rock type can be
subjected to intense
heat and pressure.
 Commonly occurs at
plate boundaries and
volcanically active
areas, including
hotspots.
 Forms metamorphic
Rocks
Metamorphic Rocks
 Formed through intense
heat and pressure without
melting the rock.
 Folds are created in the
rock due to grain/crystal
alignment from intense
pressure.
New crystals form due to the rearrangement
(not melting) of original crystals in the rock matrix.
Magma
Igneous
Rocks
Metamorphic
Rocks
The Rock
Cycle
Heat &
Pressure
Sediment
produced by
erosion
Sedimentary
Rocks
The Never-ending Cycle