The Rock Cycle 3.1

Rock• A consolidated mixture of minerals.

Igneous Rock

• A rock formed by the crystallization of molten magma.

Sedimentary Rock• Rock formed from the weathered

products of preexisting rocks that have been transported, deposited, compacted, and cemented.

Metamorphic Rock• Rock formed by the alteration of

preexisting rock deep within Earth by heat, pressure, and/or chemically active fluids.

Rock Cycle• A model that illustrates the origin of the

three basic rock types and the interrelatedness of Earth materials and processes.

Magma• A body of molten rock found at depth,

including any dissolved gases and crystals.

Lava• Magma that reaches Earth’s surface.

Weathering • The disintegration and decomposition of

rock at or near Earth’s surface.

Sediments

• Loose particles created by the weathering and erosion of rock, by chemical precipitation from solution in water, or from the secretions of organisms and transported by water, wind, or glaciers.

Key Concept

• What is a rock?–A rock is any solid mass of mineral or

mineral-like matter that occurs naturally as part of our planet.

Key Concept

• What are the three major types of rocks?–Igneous, Sedimentary, and

Metamorphic.

Key Concept • How do igneous, sedimentary, and

metamorphic rocks differ?–Igneous rock are formed when magma

cools and hardens, Sedimentary rocks are formed when sediments are compacted and cemented, Metamorphic rocks are formed under extreme pressure and temperature conditions.

Key Concept

• What is the rock cycle?–Processes driven by heat from Earth’s

interior are responsible for forming both igneous and metamorphic rocks. Weathering and the movement of weathering materials are external processes form sedimentary rocks.

Key Concept

• What powers Earth’s rock cycle?–The energy/heat from the sun powers

Earth’s rock cycle.