130 likes | 242 Views
ROCKS. Rocks. a naturally occurring solid mixture composed of minerals, smaller rock fragments, organic matter, or glass. Grains – individual particles in rock. Types of Rocks. Igneous – most abundant on Earth Formation
E N D
Rocks • a naturally occurring solid mixture composed of minerals, smaller rock fragments, organic matter, or glass. • Grains – individual particles in rock
Types of Rocks • Igneous – most abundant on Earth • Formation • Molten rock (magma) erupts onto the earth (lava) and cools • Texture/Composition • Fine-grained (small crystals) • Coarse-grained (large crystals)
Types of Rocks • Sedimentary • Formation • Lithification – process through which sediment (loose rock and mineral fragments) turn into rock • Layers of sediment build up and the weight of top layers compact the sediments into rock • Texture/Composition • Fine or coarse grained • Rounded (older) or angular (younger)
Types of Rocks • Metamorphic • Formation • Parent rocks are squeezed or heated forming new rocks • Texture/Composition • Foliation – uneven pressures cause flat minerals to line up, giving the rock a layered appearance
Uses of Rocks • Hard and durable (granite, limestone) • construction, building • Soft with hard pieces (pumice) • polishing/cleaning • Foliated (slate) • roofing shingles • Soft (marble) • carving/sculpturing
The Rock Cycle • Series of processes that continually change one type of rock into another
Processes of the Rock Cycle • Cooling and Crystallization • Extrusive Rock – igneous rocks that form from lava that erupts, cools, and crystallizes on Earth’s surface • Intrusive Rock – igneous rocks that form from magma that cools and crystallizes inside Earth
Processes of the Rock Cycle • Uplift • Process that moves large amounts of rock up to the Earth’s surface • Associated with development of mountains • Weathering and Erosion • Breaking down and transporting of rock due to the environment (wind, glaciers, rain, organisms)
Processes of the Rock Cycle • Deposition • Process of laying down sediment in a new location • Forms layers of sediment • Compaction and Cementation • Weight of overlying layers pushes grains of sediment closer together • Crystallized minerals cement the grains together
Processes of the Rock Cycle • Temperature and Pressure • Rocks under high temperatures and pressures undergo metamorphism • High enough temperatures cause the rocks to melt into magma to become igneous again
Rocks and Plate Tectonics • Most changes to rocks occur at tectonic plate boundaries (volcanoes, mountains, earthquakes, etc.)