Erosion

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Chapter 12

• Erosion Deposition

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Section 1 Shoreline Erosion and Deposition

• Erosion process that moves weathered sediments
  from one location to another
• Deposition deposit of sediments

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• Causes of Erosion
• 1.) gravity
• 2.) running water
• 3.) glaciers
• 4.) wind

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Wave Energy

• Shore line
• Def____________
• Wave Trains
• Def____________
• How Waves Build
• Wave Period
• Def____________
• Time between waves 10 to 20 seconds

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Wave Erosion

• Sea Cliffs
• Def____________
• Landforms (see Figure 4 pg 344)
• Sea Stack Def____________
• Sea Arches Def____________
• Sea Caves Def____________
• Headlands Def____________
• Wave Cut Terraces Def____________

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Wave Deposits

• Beach
• Def____________
• Differences in beaches
• Causes ____________
• Longshore Current
• Def____________
• Causes
• Effects

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Wave Deposits

• Deposit Types
• Causes _________
• Sandbars
• Def____________
• Barrier Spits
• Def____________

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Section 2 Wind Erosion and Deposition

• Wind erodes by deflation and abrasion
• Deflation wind picks up and moves small
  sediments
• Saltation
• Def____________

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• Abrasion
• Def____________
• Example
• Wind makes sand grains roll and skip along the
  ground, they bump into other grains.
• The struck rocks become pitted and polished when
  small fragments are broken off

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• Deposition
• Loess
• Def____________
• sediments settle, particles pack together
  creating a thick deposit

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• Dunes
• Def____________
• Formed when sediments collect behind an obstacle,
  most common wind deposits (sand)
• Slip Face
• Def___________

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Section 3 Erosion and Deposition by Ice

• Glaciers
• moving mass of ice and snow

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Alpine Glaciers

• Valley Glaciers form in the valleys of mountains

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• Rivers form V-shaped valleys
• Valley Glaciers form U-shaped valleys because
  they pluck and scrape soil at bottom

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Continental Glaciers

• Cover entire continents
• ex. Greenland and Antarctica

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• Form in areas with annually cold climates
• Last Ice Age in North America ended 10,000 years
  ago
• Can be as thick as 4,000m in places

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Alpine Glacier Landscapes

• Horns
• Features____________
• Cirques
• Features ____________
• Arêtes
• Features ____________
• U-Shaped Valleys
• Features ____________
• Hanging Valleys
• Features ____________

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• Plucking
• Glacier melts, water enters cracks in rocks,
  freezes and breaks the rock apart, pieces are
  carried with glacier
• Occurs near the top of a mountain or a rock wall

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Glacial Deposition

• Till
• Unsorted mixture of boulders, sand, clay, and
  silt
• Till is deposited when a glacier stops
• Till is deposited in front of the glacier too

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Types of Moraines

• Lateral Moraines
• Features____________
• Medial Moraines
• Features____________
• Ground Moraines
• Features____________
• Terminal Moraines
• Features____________

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Stratified Drift

• Stratified Drift
• Def___________
• Kettle Formation
• Caused by____________

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• Outwash sediments deposited by the glaciers
  melted ice

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Section 4 Effect of Gravity on Erosion and
Deposition

• Mass Movement
• Def___________
• Angle of Repose
• Def___________
• Characteristics _________

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Rock Falls or Rockslide

• Large blocks of rock break loose from steep
  slopes and tumble quickly to the bottom

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Landslide or Slump

• Most common type
• Loose materials or rock layers slip downward as
  one large mass
• Causes ________

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Mudflow

• Ground becomes saturated and begins to flow
  downhill
• Occurs in Mountainous regions when a long dry
  season occurs followed by heavy rains

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Lahars

• Cause ________
• Can travel up to 80 km/h
• Different from Mudslides because _____
• Occur in areas with volcanoes in icy reagions

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Creep

• Sediments slowly creep down a hill
• Factors
• Type of soil
• Burrowing animals and type of plants growing in
  the region

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Notes from Speaker Running Water

• Rill erosion small stream forms during a heavy
  rain, begins a path for future water

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• Gully erosion stream channel becomes broader and
  deeper, carries away soil

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• Sheet erosion rainwater collects in a flat area
  until it flows into a lower elevation carrying
  sediments with it
• Water erodes more than any other agent