Rocks Rock – any solid mass of mineral or mineral-like matter that occurs naturally on Earth Rock Cycle – the continuous processes that cause rocks to change. What factors can change a rock? Interactions among Earth’s water, air, and land can cause rocks to change from one type to another.

Igneous Rocks Mount Rushmore Formed from molten rock When magma or lava cools and hardens Mount Rushmore

Sedimentary Rocks Formed from small sediments (pieces of earth materials) Weathering & removal of rock  deposition  compaction and cementation Weathering: the process in which rocks are physically & chemically broken down by water, air, and living things Erosion: the incorporation and transportation of agents, such as, water, ice, wind, or gravity.

Metamorphic Rocks Metamorphic – changes in rocks due to increased temperatures and pressures a few kilometers below Earth’s surface

Igneous Rocks Formed from molten rock Intrusive Igneous – formed when magma hardens beneath Earth’s surface Extrusive Igneous – formed when lava hardens above Earth’s surface Characterized by grain sizes and composition Texture Coarse-grain – large grains Fine-grain – small grains Glassy – no crystals Porphyritic – mixture of grain sizes Composition Granitic – light-colored Basaltic – dark-colored

Sedimentary Rocks Types of Sedimentary Rocks Formed from small pieces/sediments Weathering and removal of rock  deposition  cementation and compaction Types of Sedimentary Rocks Clastic Sedimentary – weathered bits of rock Chemical and Biochemical Sedimentary – dissolved substances precipitate from a water solution

Metamorphic Rocks Types of Metamorphic Metamorphic – changes in rocks due to increased temperatures and pressures a few kilometers below Earth’s surface Contact Metamorphism – magma leaks into cracks in existing rocks Regional Metamorphism – large-scale deformation of rocks (mountain-building) Types of Metamorphic Foliated – banded, or layered, rocks Nonfoliated – not banded