Ch 27.1 Flashcards
What is Weathering
Weathering is a process that involves the physical or chemical breakdown of materials on earths surfaces
Do rocks weather at the same rate
No, they weather at different rate
What are the two main factors that determine how fast a rock will weather?
- Rock type
2. landscape
What are the two types of weathering
- Mechanical weathering
2. Chemical weathering
What type of change happens with mechanical weathering
physical changes
What type of change happens with chemical weathering
Composition and color changes
What are the 3 specific types of mechanical weathering?
- Frost wedging
- Biological activity
- Collisions
What causes frost wedging?
Occurs when water collects in the cracks of and then freezes
What is the cycle called during frost wedging?
Freeze-Thaw Cycles
What cause biological activity
Plant and animal activity
What causes weathering during collisions?
When rocks fall from a cliff or tumble through turbulent rivers
what are the 2 types of chemical weathering
- Oxygen
2. Water
What are chemical changes due to oxygen
Oxidation
and rust
What are chemical changes due to water
The process chemical reaction is called hydrolysis
What is soil?
Is a mixture of weathered rock, organic matter, water, and air that is capable of supporting life.
What is a parent material
Is where soil forms from
What are soil horizons
They are the different layers of soil
How many soil horizons are there
there can be up to 6
True or False. All soils contain every soil horizon
False
What are the specific soil horizon?
Letters O A E B C R
What does the first soil horizon contain?
O. Organic material
What is the second soil horizon mostly made up of?
M. Minerals
Which layer does leaching occur?
E. Finer sediment, lets more soluble materials go deeper, known as leaching
Which horizon collects materials from previous horizons?
B. Collects materials from above
Which layer is partially weathered bedrock?
C. Partially weathered bedrock
Which layer is unweathered bedrock?
R. UnWearthered bedrock
Which soil horizons make up the topsoil
O and A
Which soil horizons make up the subsoil?
E and B
Which Horizon makes up the true soil
O, A, E, and B
