Weathering

1. Weathering Lesson 2.1 – 2.3

2. Main Ideas of the Unit • How does weathering change Earth’s surface? • Define weathering • Define Physical weathering • Define chemical weathering • Be able to identify certain types of physical weathering • Be able to identify certain types of chemical weathering • List examples of physical and chemical weathering

3. Weathering • It is the process by which rock materials are broken down by the action of physical and chemical processes • 2 types of weathering are chemical and physical

4. Physical Weathering • Breaking down of rocks into smaller pieces by physical means • Types of physical weathering include – temperature change, pressure change, wind, water, gravity, and plant & animal actions. • Weathering can be caused by ice wedging, abrasion, exfoliation, plant growth and animal burrowing

5. Chemical Weathering • Process by which rocks break down as result of chemical reactions • Types of chemical weathering include water, acids, and oxygen • Acids cause chemical weathering through acid precipitation, acids in groundwater, and acids in living things • Oxidation occurs when oxygen reacts with compounds that make up rock. Rock surfaces can change color because of oxidation, such as when iron in rocks turns reddish orange.

6. Homework • Define the following words using a “definition wheel” • Weathering • Abrasion • Physical weathering • Oxidation • Chemical weathering • Acid precipitation ** on each spur – you write a detail about the term (aim for at least 3 details) TERM

7. Homework – cont. • Read pgs 18 – 26 • Answer #7, 10, 12 & 13 on a separate sheet of paper