Weathering Erosion and Deposition

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					Weathering, Erosion and
             Deposition
Factors that affect the surface
         of the Earth.
Weathering
• The breakdown do the materials of Earth’s crust into
  smaller pieces. It can happen through physical or
  chemical means and through natural and man made
  processes.
Weathering

• Mechanical or Physical is physical disintegrating. Smaller
  pieces are formed, cliffs break off into pebbles and the
  pebbles into sand. Only the size changes, not the
  chemical composition.
• Chemical involves a chemical change in at least some of
  the minerals within a rock. It involves rainwater, oxygen,
  carbon dioxide, and plant decay acids
       Physical Weathering
• Process by which rocks are broken down into
  smaller pieces by external conditions.
• Types of Physical weathering
  –   Frost heaving and Frost wedging (ice wedging)
  –   Plant roots
  –   Friction and impact
  –   Burrowing of animals
  –   Temperature changes
Frost Wedging
Frost Heaving
Plant Roots
Friction and Repeated Impact –
usually by water but also by wind
Burrowing of Animals
Temperature Changes
Chemical Weathering
• The process that breaks down rock
  through chemical changes.
• The agents of chemical weathering
  –   Water (weak acids)
  –   Oxygen (Oxidation)
  –   Carbon dioxide (Carbonic Acid)
  –   Living organisms
  –   Acid rain
Water
• Water weathers rock by dissolving it
     Oxygen
• Iron combines with
  oxygen in the presence
  of water in a processes
  called oxidation
• The product of
  oxidation is rust
Carbon Dioxide
• CO2 dissolves in rain water and creates
  carbonic acid
• Carbonic acid easily weathers limestone
  and marble
Living Organisms
• Lichens that grow on rocks produce weak
  acids that chemically weather rock. This
  is also called biological weathering.
     Acid Rain
• Compounds from burning coal, oil and gas react
  chemically with water forming acids.
• Acid rain causes very rapid chemical weathering
Weathering Activities
• Group reports
  – Summarize your findings
• Weathering worksheet

• Weathering project
  – You pick
• Plop Plop..Fizz Fizz           • Shake, Rattle and Roll
*Students combined calcite       * Students placed items into four
   and HCL. Chemical                jars
   weathering because of the     Jar 1 – sugar cube
   release of gas (bubbles)      Jar 2 – two sugar cubes
*Grinding calcite increased      Jar 3 – rock and sugar cube
   surface area with increased   Jar 4 – rock, sugar cube and
   rate of reaction                 water
                                 IV –
                                 DV –
  Song, Collage or Storyboard
• Read the scoring guide so you know how you will be graded
• DON”T FORGET TO CITE!!!!!!!!!!
• Collage
   – Cover entire space with pics…use agents as labels (oxidation, plant
     roots, weak acids etc..)
• Song
   – Make sure words flow with music
   – Record for extra credit
   – Use all vocab words and meanings
• Storyboard
   – Pick one example of weathering and divide the process into five
     frames
   – Example: Oxidation…draw five frames of an object rusting from
     beginning to end
Soil formation
• Soil is a combination of weathered rock,
  dead plants and animals, minerals and
  waste
• How long does it take for soil to develop?
• Let’s Get Dirty!!!!!
• Idealized soil model
  Soil Profile Project
Overall goal: Creating a soil profile of a climate
   region of the world.
1. Find the climate you are doing through
   latitude and longitude readings.
2. Do some quick reading about the climate
   (Biome) to determine the characteristics of
   that soil profile.
3. Create the profile and fill in a chart on the
   characteristics of soil in that region
Process
   Get a sheet from your teachers that lists the
    latitude and longitude of your climate
   Using the websites listed on
    ikeepbookmarks.com/msmo find your climate
    region.
   Quickly research the characteristics of the soil
    profile of that region.
   Create and label your soil profile showing the
    layers and processes that affect the soil.
   Create a poster, power point, newspaper that has
    1)your biome labeled at the top, 2) world map
    with your biome highlighted, 3) a chart of your
    biomes soil characteristics and 4) soil profile
    labeled on it
             Scoring Guide

1. Biome name neatly and easily
   seen (2 points)
2. Labeled diagram of typical soil
   profile (refer to other sheet)
3. World Map with biome colored in
   (3 points)
4. Chart on what you would see if you
   actually took a sample of soil from
   that region. Make sure you
   imagine that there is a sample of
   soil in front of you. (5 points)
Where is your biome?
Group Number   Coordinates          Biome
1              70N:100E, 75N:80W

2              0:70W, 10N:80E

3              40N:100W, 15N:15W

4              70N:155W, 80N:80E

5              35N:90W, 30N117E

6              10S:50W, 25N: 117E

7              25N:85E;30S:140E

8              37N:10E;30N:60E
  Virtual Soil lab
  Pretend like you have returned to you well equipped lab with a very large sample of soil.
  You perform with your group a wide range of test. Fill in the information you find after
  completing these test in the chart below.

  Characteristic of ______ Soil
Color of       Evidence of        Evidence of          Type of rock/ Other
soil           animals            plants present       minerals      characteristics
               present                                 present
Erosion
• The process by which water, ice, wind or
  gravity moves fragments of rock and soil.
   Erosion….
• Process in which surface materials are worn
  away (weathered) and then transported from
  one place to another by agents such as gravity,
  water, wind and glaciers and deposited.
• More common
  on steep slopes
  than gentle
   slopes (duh!)
Deposition…
• Dropping of sediment that occurs when agents of erosion
  lose energy and can no longer carry the load (dirt, rock etc)
• Occurs when
   – water slows down due to widening of stream/river or
      topography of land… or …
   – items are simply to dense to be carried




               New Orleans

                              Nile Delta
 Erosional Forces (Agents)
• Gravity
  – Mass movement
     •   Slump
     •   Creep
     •   Rock falls and rock slides
     •   Mudflows
• Glaciers
  – Plucking
  – Transporting and Depositing
• Wind
  – Deflation and abrasion
  – Sandstorms and dust storms
Erosional Forces (Cont.)
• Water
  – Runoff
     • Water follows same path because it is cohesive
     • Scours out rills, valleys, gullies
  – Groundwater
     • Permeability and composition of soil determine how much
       water will affect the land
  – Shoreline
     • Tides
     • Hurricanes
     • Storms
Mass Movements
• Landslides, mudslides, slump and creep




                              landslide clip.mpeg
Ice Erosion
• Glaciers
Wind Erosion
Water Erosion
• Rivers, streams, and runoff
 Causes                               Prevention
 of Erosion                             of Erosion
• Agricultural Cultivation         • Manage crops
   – Over-plowing                     – Leave some items to hold
   – Not rotating crops                 in soil
• Forest Harvesting                   – Maintain tree lines
                                      – Planting along the contour
   – Removing trees to plant
                                        of the land
     crops
                                      – Terracing
• Overgrazing
   – Allowing animals to eat the
                                   • Spraying water on bare soil
     grass on one area to long     • Adding netting and straw
• Urban Construction               • Retaining walls
Erosion In Action
• Complete lab
• Landslide Video
Final Project….
         • ABC…Easy as 1 2 3
                   (Cue the Jackson 5)


         • Create an ABC book on
           weathering, erosion and
           deposition.