1. Chapter 2
Lesson 1 – Weathering

2. Weathering
physical and chemical processes that change objects on Earth’s surface over time, causing them to break down
Examples – paint fading, metal turning rusty, wood drying out, rocks turning smooth
How long does it take?
Long time
Breaks, wears, abrade, or chemically change
Sediments – rock that has been broken into small pieces through weathering

3. Mechanical weathering –
physical processes naturally breaking down rock
Ice (frost) wedging
ice expanding inside of rock to force it apart
Abrasion
grinding away of rock by friction or impact
Plants/Animals
Surface area
how much surface something has

4. Chemical weathering – change in rock into a new material Examples
Water – important because water can dissolve material
Acids – breaks down materials faster than water
Oxidation – combines oxygen with other elements or molecules (RUSTING)

5. Rate of weathering The environment – water, temperature, wind
The rock – material, size
Environment – physical, chemical, and biological factors acting in a community

6. Chapter 2
Lesson 2 - Soil

7. What is soil?
a mixture of weathered rock, sediment, decayed organic matter, water, and air
Organic matter
the remains of something that was once alive
Pores
small holes and spaces in soil
provides space for water and air to move
Decomposition
the process of changing once-living material into dark-colored organic matter
Inorganic
materials that have never been alive
Sand, silt, and clay

8. What is parent material?
starting material of soil (source of soil) – where the soil comes from
Topography
the shape of land
Biota
all living things in a region

9. Soil takes a long time to form – thousands of years Horizons
layers of soil formed from the movement of sediments
A-horizon - dirt (lots of organic matter)
B-horizon - clay
C-horizon – parent material
Soil properties
Color, texture, structure, consistency, infiltration, soil moisture, pH, fertility, temp