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>Earth as a system: the rock cycle

The rock cycle begins with magma

Forms from melting in Earth’s crust and upper mantle

Less dense magma rises toward the surface

Erupts at surface as lava or cools within crust

Cooling is called crystallization or solidification

>The Basic Cycle

Igneous rocks are crystallized from

Magma (within the crust)

Or lava (at Earth’s surface)

Igneous rocks exposed at Earth's surface undergo weathering

Atmosphere decomposes rock

Generates loose material or dissolves it

Loose material is called sediment

Transported by gravity, running water, glaciers, wind, waves, etc.

Deposited sediment undergoes lithification

“Conversion into rock” by

Compaction

Cementation

Deformed by great heat and pressure if deeply buried or incorporated into a mountain chain

Metamorphism

Eventually enough heat will melt the rock and generate magma – may eventually become igneous rock again

Deposited sediment undergoes lithification

“Conversion into rock” by

Compaction

Cementation

Deformed by great heat and pressure if deeply buried or incorporated into a mountain chain

Metamorphism

Eventually enough heat will melt the rock and generate magma – may eventually become igneous rock again