Rocks Rock – any solid mass of mineral or mineral-like matter that occurs naturally as part of our planet Rock Cycle – the continuous processes that cause rocks to change

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 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 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