Subaerial Processes

• What is a subaerial process?

  Land based processes that occur OUTSIDE of the water, above the water line, and alter the shape of the coast
• Name the two types of subaerial processes that occur in coasts:

  • Weathering
  • Mass Movement
• What is weathering?

  The breaking down of rocks due to the day to day changes in the atmosphere (weather)
• List the 3 main types of weathering:

  • Chemical Weathering 
  • Mechanical Weathering (freeze-thaw) 
  • Biological Weathering
• What is mass movement?

  The downhill movement or sliding of material (usually rock or soil) due to gravity
• List the 3 main types of mass movement:

  • Sliding 
  • Slumping
  • Rockfall
• What happens in freeze-thaw weathering?

  1. Water enters cracks in the rock.
  2. When temperatures drop, the water freezes and expands causing the crack to widen.
  3. The ice melts and water makes its way deeper into the cracks.
  4. The process repeats itself until the rock splits entirely

  
• What is biological weathering?

  • the process where plants, animals, and microbes break down rocks.
  • happens through roots growing into cracks, animals burrowing, or microorganisms producing acids that weaken the rock
• What is freeze-thaw weathering?

  Freeze-thaw weathering is a type of mechanical weathering that happens when water enters cracks in rocks, freezes, and expands
• What happens in biological weathering?

  1. Plant roots can get into small cracks in the rock.
  2. As the roots grow, the cracks become larger.
  3. This causes small pieces of rock to break away

  
• What is chemical weathering?

  • the breakdown of rocks due to chemical reactions.
  • happens when minerals in the rock react with substances like water, oxygen, carbon dioxide, or acids, causing the rock to weaken and change
• Rockfall in mass movement:

  Bits of rock fall off the cliff face, usually due to freeze-thaw weathering.

  
• Mudflow in mass movement:

  Saturated soil (soil filled with water) flows down a slope.

  
• Landslide in mass movement:

  Large blocks of rock slide downhill.

  
• Rotational slip in mass movement:

  Saturated soil slumps down a curved surface