1. Chapter 10 Weathering and Soil Formation
Sections 1, 2, 3, and 4

2. Weathering is the process in which rocks break down.

3. Types of Weathering
Mechanical weathering happens when rocks are broken into pieces by physical means, such as water, ice, wind, gravity, plant growth, animals, and abrasion.

4. Types of Weathering
The process of the freezing and thawing of ice is an agent of mechanical weathering.
Water gets into cracks in rocks, freezes, melts, freezes, and melts over and over again. This causes the rock to break apart into smaller pieces.

5. Types of Weathering - Mechanical
Abrasion is a kind of mechanical weathering that happens when rocks are worn away by contact with other rocks. Water, wind, and gravity are some of the agents that create the abrasion.

6. Types of Weathering
Plant Growth – roots of plants can split rocks as they grow.

7. Types of Weathering Animals
As animals move, their motion breaks rocks into smaller pieces.

8. Chemical Weathering
Chemical weathering happens when rocks break down by chemical means.

9. Chemical Weathering

10. Chemical Weathering
Factors of chemical weathering comes from water, acid precipitation, acids in ground water, acids from living organisms, and the air.

11. Chemical Weathering Acid Precipitation
Rain, sleet, or snow that contains more acid than normal is acid precipitation.

12. Chemical Weathering Acid in Ground Water
When ground water flow through rocks underground, the may water may contain weak acids. When this water touches certain kinds of rocks, chemical actions occurs.

13. Chemical Weathering from Living Organisms AKA: Biological Weathering
Chemicals from plants and animals may cause rocks to break down.
The chemicals from lichens break down rocks over time.

14. Differential Weathering

15. How does a rock surface affect weathering?
Rocks with a lot of surface area weather faster than rocks with little surface area.
However, if the rock has a large volume as well as surface area, it takes longer for the rock to wear away. Think about Stone Mountain, it has a large surface area and volume.

16. How does climate affect weathering
Climate is the average weather conditions over a long period of time.
Three features of climate that affect weathering are: temperature, moisture, and elevation/slope.

17. Elevation and Slope

18. Chapter 10 Lesson 3 from Bedrock to Soil
Words to Know
Soil – a loose mixture of small mineral pieces, organic material, water, and air
Parent Rock – The rock that breaks down to form a soil
Bedrock – layer of rock beneath soil… This may be the parent rock or may not be the parent rock.
Soil Texture – the amount of soil particles of different sizes that a soil contain
Soil Structure – Describes the arrangement of particles in the soil
Humus – organic material that forms in soil from the remains of dead plant and animals

19. Soil Layers
O, A, E, B, C, R

20. What is pH? The pH is how acidic or alkaline something is.
0 to 7 is acidic and 7 to 14 if basic, while 7 is neutral.
Most plants grow best when the soil pH is between 5.5 to 7.0