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 -formation -destruction -alteration -reformation 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 generation and movement of magma weathering erosion 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.

Sediment produced by erosion Magma Igneous Rocks Metamorphic Rocks The Rock Cycle Heat & Pressure Sediment produced by erosion Sedimentary Rocks

The Never-ending Cycle