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Aim: What is Erosion?. Objective: Ability to differentiate the different type of weathering Vocabulary : mechanical weathering, chemical weathering, carbonation, oxidation, hydrolysis Catalyst, sediment, glaciers. Interactions of the Spheres. Definition of Erosion.
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Aim:What is Erosion? Objective: Ability to differentiate the different type of weathering Vocabulary: mechanical weathering, chemical weathering, carbonation, oxidation, hydrolysis Catalyst, sediment, glaciers
Definition of Erosion • Process in which weathered pieces of the lithosphere are moved from on place to another • Occurs because of Weathering
Weathering • Is the decay of rocks, minerals, mountains, and other hard surfaces of the earth • The decay breaks larger particles into smaller ones • The decay can either be mechanical or chemical or both
Physical Weathering • Gravity • Running Water • Freeze-Thaw Cycle • Wind • Glacier
What happens when two rocks bang into each other? • Little chips of the rocks break off • Sometimes large chips, sometimes small ones. • Multiply that by 1,000,000 years • Will the original rocks be larger or smaller • Mechanical Weathering
Freeze-Thaw Cycle If you put a can of soda in the freezer what happens? The same things happens in nature when water freezes Over millions of years – changes the lithosphere breaking parts of it into millions of pieces
Freeze Thaw Cycle When the rock finally breaks up there, what causes it to fall ? gravity
What happens when water rushes down a mountain • Brings everything with it • Soil • Rocks • Now multiply that effect by 10,000,000 years
How dramatic can the effect be? • Most of the sand deposits on the east coast are the weathered remains of granite mountains from … • Appalachian Mountains
Running Water The faster the water runs, the larger the particles (sediment) the water is able to move !
Running Water • Moves things “down-stream” • Created the Grand Canyon over 30,000,000 years • Literally washed mountains down valleys • And sometimes into the oceans • Creates new landforms
Running Water Creates Deltas Where did this whole landform come from?
Glaciers • Extremely Vast Regions of Ice/Snow • Millions of Years Old • Continental (Greenland – Antarctica) • Mountain (Alpine) Glaciers
Glaciers • Move rock and sediment in their path • When they retreat (melt), the carried remains are left behind • Formed Long Island – last Ice Age • Sometimes they form hill, and lakes • Drumlins and the Finger Lakes
Chemical Weathering Chemical weathering is where the rock material is changed into another substance by reacting with a chemical. • Oxidation: • Hydrolysis:
Oxidation is another form of chemical weathering • Your bicycle if made of iron • What happens to it in the rain • Turns to rust • Oxygen + Iron = Iron Oxide (rust) • Water is a catalyst = speeds up the process
Weathering can also be chemical • Carbon dioxide (air) mixes with water (rain) to form carbonic acid • Carbonic acid can dissolve some sedimentary rocks – particularly limestone • Over millions of years this forms large caves and caverns. (Howe Caverns) • Often when water combines with limestone or marble an acid is formed
Hydrolysis is another form of chemical weathering • Water has a tendency to dissolve other substances • Water is called the universal solvent • When water combines with another substance is called hydrolysis
Rates of weathering will be influenced by surface area: More surface exposed, the faster the weathering will occur.
1. What type of steam carries more sediment? a)Fast moving b)Slow moving c)No correlation
2. What type of steam cause more erosion? a)Fast moving b)Slow moving c)No correlation
3. During a heavy rain, a stream probably moves a)Faster b)Slower c)No correlation
4. During a heavy rain, there is probably _______ erosion a)more b)less c)No correlation
5. During a hurricane, there is probably _______ erosion a)more b)less c)No correlation
6. There is more gravitational erosion on a ______ slope. a)Steep b)gentle c)No correlation
7. There is more erosion on a ______ flowing stream a)Steep sloping b)Gentle sloping c)No correlation
8. Freeze-Thaw reactions a)Create sediment b)Reverse seditment c)No correlation
9. How was Long Island created • Chemical Weathering • Erosion • Glaciers (glaciations)
10. Deltas are created from • Wave Action • Carried sediment from upstream • Glaciers