Constructive and Destructive Forces Study Guide

  1. Vocabulary
  2. Earth’s layers: The crust and mantle are divided into sections called plates, which “float” on the softer rock of the __mantle______. These plate movements cause many changes in Earth’s surface.
  3. Crust – surface layer of the Earth. It is solid rock.
  4. Mantle – made up of two layers – a solid rock layer and a soft rock layer.
  5. Outer Core – hot, liquid iron.
  6. Inner Core – made of iron and nickel. It’s solid.
  7. Landforms: Natural land shape or feature.
  8. Canyon – carved by rivers flowing through rock layers (_water___ erosion)
  9. Mesa – forms as running water erodes the surrounding rock (water erosion)
  10. Sand dune – made and shaped by wind – found in deserts, beaches, and lakeshores (wind erosion and deposition)
  11. Sand spit and barrier island – land, narrow piles of sand that are formed by watering moving sand. They help protect the mainland from wave erosion. (water erosion and deposition)
  12. Delta – a area of new land at the mouth of a ____river______. It is formed when a river slows and deposits sediment. (deposition)
  13. Sinkholes – forms when a cave near the surface of the Earth collapses. (gravity)
  14. Mountains – the tallest landforms on Earth. (plate movements)
  15. Volcanoes – a type of mountain that forms when a plate moves over a __hot______spot___ (plate movements and volcanic eruptions)
  1. Processes – these activities cause changes in landforms
  2. ___weathering______– breaking down of sediment

Examples of weathering: waves constantly crashing into a cliff, plants growing in a crack in a rock, sand blowing against a rocky surface,

  1. ___erosion______– carrying away of sediment

Examples of erosion: sand being carried away from a beach by wind or water, sediment being washed away by a river,

  1. ___deposition______– the dropping off of sediment

Examples of deposition: formation of a delta, a river getting narrower and shallower

  1. ___Plate______Movement – whether towards, away from, or alongside each other, plate movements cause earthquakes, mountain formations, and volcanoes
  1. Technology and Human Intervention
  2. GPS – helps seismologists measure movement of __faults______
  3. Seismographs – records movement of the Earth’s crust
  4. Beach restoration – replacing sand on the beach
  5. Jetty – prevents the current from carrying away ___sand______
  6. Levee – keeps rising water within channels
  7. Coral reefs – both natural and man-made prevent erosion from water
  8. Dams – control flow of rivers – creates lakes
  9. Miscellaneous
  10. Mountains, volcanoes, and earthquakes are all __natural______processes that are caused by Earth’s ___plate______movements__.
  11. To model the process that causes an earthquake, which would be better to use? Two sponges rubbing against each other or a bowl of jiggling gelatin

Why?

__Plates float on soft, melted rock. ______

  1. To make a model of an erupting volcano, which would be better to use?

A lit firecracker or a shaken can of soda – Why?

___A volcano erupts under pressure just like a shaken can of soda _____