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

IgneousSedimentaryMetamorphic

Rock Formation

Is a sequence of events that may involve one or all of the following processes:

-formation

-destruction

-alteration

-reformationThe original state of all rocks on earth is Magma.

Rock Evolution

Created by the following geological processes:Created by the following geological processes: generation and movement of magma weathering erosion transportation deposition of sediment metamorphism of preexisting rocks.

Magma

Requires HeatMelted rockFound under the

earth’s crustKnown as “lava”

above the earth’s crustCrystallizes to form

Igneous Rocks

Igneous Rocks

Requires crystallization Intrusive - crystallized

inside the earthExtrusive - 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 RocksRequires 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 PressureAny 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 RocksFormed 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

Sediment produced by

erosion

Sedimentary Rocks

Heat & Pressure

Metamorphic Rocks

The Rock Cycle

The Never-ending Cycle