3 TYPES OF ROCKS

ROCK

• rock: a combination of one or more mineral or organic matter
• determined by mineral composition and texture

3 TYPES OF ROCKS

• Igneous
• Sedimentary
• Metamorphic

IGNEOUS ROCK

INTRUSIVE IGNEOUS ROCK

• cools outside of earth's surface, cools slowly
• large and visible crystals, coarse grained texture
• examples of Intrusive Igneous Rock: granite, diorite

EXTRUSIVE IGNEOUS ROCK

• forms when lava erupts onto earth's surface, cools quickly
• fine-grained texture, little to no crystal formation
• examples of Extrusive Igneous Rock: obsidian (volcanic glass)

SEDIMENTARY ROCK

CLASTIC SEDIMENTARY

• form when sediments are buried, compacted, and cemented together
• classified by size of sediment/clasts
• examples of Clastic Sedimentary Rock: mudstone, siltstone, shale (fine-grained), sandstone (medium-grained), breccia, conglomerate (coarse grained)

CHEMICAL SEDIMENTARY ROCK

• form when water/seawater evaporates
• minerals in the water precipitate out of the solution and crystallize
• examples of Chemical Sedimentary Rock: Halite

ORGANIC SEDIMENTARY ROCK

• form from the remains or fossils of once living plants and animals
• examples of Organic Sedimentary Rock: Coquina (a fossiliferous limestone), chalk, coal

METAMORPHIC ROCK

FOLIATED METAMORPHIC ROCK

• foliation occurs when mineral grains are arranged in planes or bands
• formed by certain temperatures and pressures
• examples of Foliated-Textured Metamorphic Rock: slate, phyllite, schist, gneiss

NONFOLIATED METAMORPHIC ROCK

• do not have mineral grains aligned in planes or bands
• made of few minerals
• examples of Nonfoliated Metamorphic Rock: quartzite, marble

3 TYPES OF ROCKS