Lithosphere

Lithosphere

• The lithosphere is made of the Earth’s crust and upper mantle.
  
  

• It is broken into large pieces called plates.
  
  

• These plates move, which is called plate tectonics.
  
  

• Plate movement changes the shape of the ocean floor.
  
  

Geological Features on the Ocean Floor

• Continental shelf: Shallow ocean area around the edges of continents.
  
  

• Seamounts: Underwater volcanoes that do not reach the ocean surface.
  
  

• Volcanic islands: Form when volcanoes grow all the way up from the ocean floor to the surface.
  
  

• Trenches: Form where two plates move toward each other.
  
  

• Ridges: Form where plates move apart and molten rock rises from inside Earth.
  
  

Continental Drainage Systems

• Mountain ranges help decide where water flows.

Glaciers

• Glaciers are large moving bodies of ice.
  
  

• Continental glaciers cover large land areas.
  
  

• When snow and ice build up, glaciers start to move.
  
  

• Valley glaciers move through mountain valleys.
  
  

Glaciers on the Move

• Valley glaciers carry rocks of different sizes.
  
  

• These rocks shape the land as the glacier moves.
  
  

Climate effects:

• Colder climate → glacier grows and moves forward (advances).
  
  

• Warmer climate → glacier melts and moves back (retreats), leaving rocks behind.
  
  

Glacial Features

• Moraines: Piles of rocks and gravel

• Eskers: Ridges of sand and gravel.

• Drumlins: Small teardrop-shaped hills.