rock cycle notes
TRANSCRIPT
Rock CycleNotes
Rock Definition• Solid mixture of crystals of one or more minerals
Value of Rock• Natural resource
– Used as tools and weapons (hammers, spears, knives)
– Used in buildings, roads, and monuments
Value of Rock ‐ History• Important to scientists
– Help answer questions about the history of earth and the solar system.• Record of what the Earth used to be• Fossils
Rock Cycle• Rocks are constantly changing• Changes shape and composition
Rock Cycle Processes• Erosion• Deposition• Compaction and Cementation• Metamorphism• Melting• Cooling• Solidification• Weathering
Rock Cycle Processes
• Weathering– Rocks attacked by weather
• Air, moisture, and living things
– Rocks broken down into sediments
• Erosion– Sediment is transported by wind, water, ice or gravity
Rock Cycle Processes• Deposition
– Sediments settle to the bottom
• Compaction and Cementation– Compaction
• Layers form on top of each other• Air and water pushed out
– Cementation• Loose sediments are glued together by natural glue
Rock Cycle Processes
• Metamorphism– Means changed form– Increased heat and pressure
– Changes a rock into a metamorphic rock
Rock Cycle Processes
• Melting– Rocks deep in Earth melt and become magma
• Cooling– Magma cools
• Solidification– Rock solidifies
Rock Classification• How they are formed• Where they are formed• Composition
– Minerals that make up a rock
• Texture– Sizes, shapes, and positions of the grains