PLATE TECHTONICS TEXT CH. 3..PG. 80 How do geologists study inside earth? Look at rock samples Can determine conditions deep in the earth by looking at rocks formed there Get rocks by drilling and blasting
Seismic waves: Waves produced by earthquakes Speed & Path of the waves are used to look at structure Earths Interior 3 layers: Crust, Mantle, Core
Vary in size, composition, temperature, and pressure Temperature increases as you go deeper Pressure (force pushing on an area) increases as you go deeper Why do you think these things increase? Crust
Outermost layer of the earth Solid rock, dry land, ocean floor Very thin5-40 km thick
Thickest crust is under mountains (up to 70 km). Thinnest under ocean floor (oceanic crust) Oceanic Crust made of basalt Continental crust mainly granite Mantle Approximately 40 km beneath the surface of
earth Solid, hot layer of rock Divided into 3 layers: Lithosphere Astenosphere Lower Mantle Lithosphere
Uppermost Mantle & lower part of the crust Rigid layer Approximately 100 km thick Asthenosphere
Hotter and more pressure Less rigidmore soft like plastic or plahdoh Bendable Thickest part of the mantle Asthenes means Weak in Latin
Lower Mantle Solid Extends to earths core Core Made mostly of iron and nickle 2 parts: Liquid outer & Solid Inner
3,486 km thick Tons of pressure hereinner core has so much pressure, it has to stay solid Creates magnetic field of the earth---Acts as a bar magnet Heat Transfer in the Mantle Section 2pg. 88
Radiation Heat transfer through Space No direct Contact Travels in waves.no particles Examples: Sunlight, Fire Conduction
Heat transfer by direct contact (touching it) Example: Spoon in soup, Touching a hot stove Particles in the bottom get hotmove faster bump into particles further up, and so on Convection Heat transferred using current action Liquids & Gases
Heat flows From one area to antoher Happens because of differences in density and pressureheat flows from high to low Convection Currents Currents caused by the movement of particles in convection Flow of heat transfer
Stops when heat source stops Examples: Weather, Ocean Currents Earths Convection Currents Liquid in the core transfers heat through convection Mantle flows very slowly causing the rock to cycle up and down
Work: Complete pg. 91 #2b & 3c ----on your notes WB pg. 56-57
