* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download plate_tectonics
Survey
Document related concepts
Geomorphology wikipedia , lookup
Physical oceanography wikipedia , lookup
Post-glacial rebound wikipedia , lookup
Schiehallion experiment wikipedia , lookup
Spherical Earth wikipedia , lookup
Magnetotellurics wikipedia , lookup
History of geomagnetism wikipedia , lookup
History of Earth wikipedia , lookup
Age of the Earth wikipedia , lookup
History of geology wikipedia , lookup
Mantle plume wikipedia , lookup
Future of Earth wikipedia , lookup
Large igneous province wikipedia , lookup
Transcript
Processes that change Earth’s surface Mr. Mathews’ 6th Grade Science Essential Question How do temperature, pressure, and composition vary as you descend through each layer of the inside of the earth? I. Earth’s Interior (review) A. Geologist & Geology -Study forces that make & shape Earth B. Surface Changes (two forces) 1. Constructive Forces - shape surface by building up mtns & landmasses 2. Destructive Forces – slowly wear away mtns and other features Constructive Force Destructive Force I. Earth’s Interior (review) C. Journey to Center of Earth 1. Temperature - Closer to center of Earth, hotter it gets. 2. Pressure – force pushing on a surface area. Increases closer to center of Earth. I. Earth’s Interior (review) D. 3 Main Layers of Earth 1. Crust – forms outer “skin” -made up mainly of basalt and granite (types of rock) - 5-40 km thick Solid or Liquid? Solid! Layers of Earth Name of Layer Crust Mantle Outer Core Inner Core Thickness Temperature Composition Degrees Celsius State (solid, liquid or gas) I. Earth’s Interior (review) D. 3 Main Layers of Earth 2. Mantle – layer of mostly solid hot rock 2,900 km thick 2 sub layers a. lithosphere – Uppermost part of mantle and crust together, lithos means stone, approx. 100 km thick b. asthenosphere – soft layer of mantle under lithosphere, asthenes weak, soft but can flow Layers of Earth I. Earth’s Interior (review) D. 3 Main Layers of Earth 3. Core – 2 Parts ~ 3,500 km thick, about size of moon. a. outer core – melted metal surrounding inner core b. inner core – thick ball of solid metal Layers of Earth Name of Layer Crust Mantle Outer Core Inner Core Thickness Temperature Composition Degrees Celsius State (solid, liquid or gas) I. Earth’s Interior (review) E. Earth’s Magnetic Field -Inner core spins faster than Earth creating magnetic field. Earth is like a huge magnet! II. Convection Currents and the Mantle Heat Moves! -Heat Transfer – movement of energy (heat) from a warmer object to a cooler object. II. Convection Currents and the Mantle (continued) A. 3 types of heat transfer 1. Radiation – transfer of energy (heat) through empty space. -no contact required ex. Sunlight Heat from a fire Radiation II. Convection Currents and the Mantle (continued) 2. Conduction – heat transfer by direct contact of particles of matter ex. A spoon in a hot pot. A pot on a hot stove Conduction Convection Currents and the Mantle (continued) 3. Convection – Heat transfer by movement of heated fluid. a. density – measure of mass in a volume of substance. Convection 3 Types of Heat Transfer Convection Currents (cc) and the Mantle (continued) b. convection current (cc) – flow that transfers heat within a fluid. i. heating and cooling of fluid, changes in density, and force of gravity cause convection currents (cc). c. (CC) occur within the asthenosphere creating movement Convection Currents (cc) and the Mantle (continued) III. Sea-Floor Spreading -Continental Drift – idea that continents slowly move over Earth’s surface Video clip III. Sea-Floor Spreading A. Mid-ocean Ridge – underwater mtn range. 1. Molten (melted) rock rises from mantle and erupts. It spreads out, pushing older rock to both sides of ridge. 2. Sea-floor spreading – process of adding new material to ocean floor. Video clip III. Sea-Floor Spreading B. Deep-ocean trenches – deep underwater canyons where ocean crust bends downward. Deep-Ocean Trenches III. Sea-Floor Spreading C. Subduction – process of ocean floor sinking into trench and back into mantle Ocean Floors and Plate Tectonics IV. The Theory of Plate Tectonics A. Theory of Plate Motion 1. Plate – broken pieces of crust/lithosphere 2. Scientific Theory – well-tested concept explaining wide range of observations. IV. The Theory of Plate Tectonics 3. Plate Tectonics – theory that states pieces of crust/lithosphere in constant, slow motion b/c of (cc) in asthenosphere. This theory explains formation, movement, and subduction of Earth’s plates. Video clip IV. The Theory of Plate Tectonics B. Plate Boundaries (3 types) -Fault – break in crust where rock slips past each other IV. The Theory of Plate Tectonics 1. Transform – 2 plates slip past each other in opposite direction -crust neither created or destroyed IV. The Theory of Plate Tectonics 2. Divergent – 2 plates move apart, or diverge -most occur at mid-ocean ridge IV. The Theory of Plate Tectonics 2. Divergent (continued) a. Rift Valley – when divergent boundary occurs on land IV. The Theory of Plate Tectonics 3. Convergent – 2 plates come together, or converge -subduction occurs or mtns are formed.