1. Crust:  the crust is the outer layer, and is made of rock.  It is the thinnest of the earth’s layers.
  2. Mantel:  The layer of rock beneath the crust.  
  3. The mantel is solid, but very hot.  It could be compared to warm plastic.
  4. Core:  The core is the center of the earth and is divided into two parts.
  5. The outer core is liquid or molten iron.
  6. The inner core is made of solid iron. 

  7. Although it is very hot, the pressure of the earth keeps it solid.

  8. The earth’s crust is not a single piece of rock.  Instead, it is made up of many plates.
  9. Although these plates are enormous, they actually float on the soft rock of the mantle.
  10. Plate movement is very slow, only a few centimeters per year.
  11. Some plates push together, while others pull apart.
  12. When plates scrape and slide past each other they shake the earth’s surface.

  13. As plates grind past each other they can slip, causing earthquakes.
  14. Mountains are Earth's highest formations.
  15. They form as the crust folds, cracks, and bends because of the movement of Earth’s plates.
  1. Volcano:  A mountain formed by lava and ash.
  2. Magma:  molten rock from the Earth’s mantel.
  3. Lava:  Magma that reaches the earth’s surface
  4. Earthquake is a shaking of the ground caused by a sudden release of energy in the Earth’s crust.
  5. Earthquakes are very common.
  6. Over a million earthquakes happen each year, however most are too  small to be felt or cause damage.
  7. Many earthquakes occur along the boundaries of the Pacific plate, or along faults in the Earth’s crust
  8. Faults are places where pieces of the crust move.
  1. Energy radiates out from the focus. The focus is the place within the Earth where the rock breaks, producing an earthquake.
  1. Energy moving outward from the focus of an earthquake travels in the form of seismic waves.  
  1. The epicenter of an earthquake is the point on the ground's surface directly above the focus.
  2. A fault is a break (fracture) or crack in the rock along which movement has occurred.
  1. Movement along a fault produces earthquakes and seismic waves.
  1.  P-waves
  1.  Surface waves

  1. The opening through which molten rock, and gases escape from a volcano is called a vent.

  2.  The bowl-like opening of a volcano is called a crater.

  3. Composite volcanoes are made up of layers of ash and lava

  4. A conduit is the name of the tube through which molten rock flows.

  5. The magma reservoir is found in the earth’s crust.

  6. The smaller vent-structure on the side of some volcanoes is called the parasitic cone.

  7. Flanks are the sides of a volcano.

  8. A sill is an intrusion of lava that has pushed its way between pre-existing layers, but doesn't cut across them.

  9. The Pangaea theory is one that states that all present continents were once together and collectively known as a super continent called a Pangaea.
  10. Pangaea means all lands in Greek, accurately defining the way the continents were 200 millions years ago before it split up.
  11. These split-up pieces drifted slowly apart and became the way they are today.
  12. Even until now, the shape of the Earth surface is still changing, and it will be forever, as long as the mantle underneath the Earth's crust gets heated and convection currents in the magma keeps dragging the plates.
  13. One prominent example of continental coastline fitting together is to fit the coastline of the West Coast of Africa with the coastline East Coast of South America.


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