weathering, erosion, and deposition 1. weathering weathering is the breakdown of rock at the...
TRANSCRIPT
Weathering, Weathering, Erosion, and Erosion, and DepositionDeposition
1. Weathering1. Weathering• Weathering is the breakdown of rock
at the Earth’s surface.• Some of these changes happen
quickly and some happen slowly.
• There are 2 Types:– Mechanical and Chemical
2. Mechanical Weathering2. Mechanical Weathering Mechanical Weathering – the type of
weathering where rock is broken down into smaller pieces without changing the chemical properties of the rock.
This can be caused by freezing and thawing, release of pressure, growth of plants, and actions of animals (including humans).
• Example: – Water seeps into a
crack in a rock– When the water
freezes, it expands
– The force of the water expanding causes the rock to crack more.
– This is called ice wedging
3. Freezing and Thawing3. Freezing and Thawing
4. Plant Growth4. Plant Growth• Roots of trees and other
plants enter into cracks of rocks.
• As the plants get bigger, so do the roots.
• The growing roots force the cracks further apart.
5. Abrasion5. Abrasion• Abrasion is the
grinding away of rock by other rock particles.
• These particles scrape away at other rocks like sandpaper on wood as they rub or roll against the surface.
6. Chemical Weathering6. Chemical Weathering• Chemical weathering is the
processes of breaking down rock through chemical changes.
• 5 things that cause chemical weathering: water, oxygen, carbon dioxide, living organisms (like lichens) and acid rain.
• Chemical weathering occurs more rapidly in warm wet climates.
• Chemical Weathering causes the rock to experience a chemical change (changes its makeup)
– Water dissolves rocks over time– Oxygen causes oxidation (rusting)– Acid rain reacts with marble and limestone– Living organisms – plant roots produce weak acids
to dissolve rock around the roots,
7. Chemical Change7. Chemical Change
ACID RAIN
OXIDATION
CHECK- UP CHECK- UP What type of weathering do
each example cause?1. The roots of a plant2. An animal scratching3. Oxygen4. Water freezing5. Acid rain6. Wind7. Water
A. Chemical Weathering
B. Mechanical Weathering
C. Both types of weathering
What type of weathering???
What type of weathering???
What type of weathering???
What type of weathering???
What type of weathering???
What type of weathering???
What type of weathering???
8. Erosion8. Erosion• When rock and soil are moved from one
place to another by natural forces, this is called Erosion.
• The agents of Erosion are– Water (rain water runoff, streams, rivers,
groundwater, and waves)– Ice (Glaciers)– Wind– Gravity ( landslides, mudslides, avalanches etc.)
9. Sediment9. Sediment• The material moved
by erosion is sediment.
• Sediment is small, solid particles of rocks or organisms.
10. Deposition10. Deposition• When the sediment being carried is
dropped (or deposited) in a new area, it is called deposition.
• Depositions can create new landforms like beaches and sand dunes.
CHECK-UP CHECK-UP • Choose
one of the following for each example:
A.) ErosionB.)Deposition
1. A river carrying sand2. Dropping sediment in a
new location3. A glacier picking up a rock
in it’s path.4. A beach is formed.5. How a sand dune is created6. How sediment is moved7. Sand being carried by the
wind in a sandstorm.