Weathering and Soil
Chapter 6
Weathering
Section 6.1
What is Weathering?
What is Weathering?
Weathering process that breaks down rocks into smaller and smaller fragments
What are the two types of weathering?
What are the two types of weathering?
Two types of weathering:
Mechanical
Chemical
Describe mechanical weathering.
Describe mechanical weathering.
Mechanical Weathering breaks apart rock with no chemical change in the rock
Give several examples of mechanical weathering.
Give several examples of mechanical weathering.
Examples of mechanical weathering:
Plant roots
Animal burrowing
Ice wedging
Describe chemical weathering.
Describe chemical weathering.
Chemical Weathering causes a chemical change in the rock
Give some examples of chemical weathering.
Give some examples of chemical weathering.
Examples of chemical weathering:
Water
Dissolve rock
Oxygen and hydrogen react with rock
Acids - Carbonic acid (naturally in rain water)
Enzymes from plants
Oxygen reacts with rock
What are some effects of climate on weathering?
What are some effects of climate on weathering?
Effects of climate on weathering:
Chemical weathering more rapid in warm, humid climates. (equatoral)
Mechanical weathering is more rapid in changeable climates. (middle latitudes)
Weathering less near poles.
Soil
Section 6.2
WHAT IS SOIL?
WHAT IS SOIL?
SOIL MIXTURE OF:
WEATHERED ROCK
ORGANIC MATTER
MINERAL FRAGMENTS
WATER
AIR
WHAT IS HUMUS?
WHAT IS HUMUS?
HUMUS DECAYED ORGANIC MATTER
DESCRIBE THE SOIL PROFILE
.
DESCRIBE THE SOIL PROFILE
SOIL PROFILE LAYERS OF THE SOIL
WHAT ARE THE LAYERS OF SOIL PROFILE CALLED?
WHAT ARE THE LAYERS OF SOIL PROFILE CALLED?
LAYERS OF SOIL PROFILE
HORIZON A TOP SOIL
MOST DEVELOPED (CHANGED)
MOST HUMUS
DARK IN COLOR
MOST ROOTS AND PLANT MATERIAL
MOST ANIMALS AND INSECTS
WHAT ARE THE LAYERS OF SOIL PROFILE CALLED?
(cont.)
LAYERS OF SOIL PROFILE
HORIZON B
LESS DEVELOPED
LIGHTER IN COLOR
LESS HUMUS
SOME PLANT ROOTS
MORE CLAY
LEACHING OCCURS
SOIL PROFILEWHAT ARE THE LAYERS OF SOIL PROFILE CALLED? (cont)
LAYERS OF SOIL PROFILE
HORIZON C
BOTTOM LAYER OF SOIL
LEAST DEVELOPED
MORE LEACHING
PARTLY WEATHERED ROCK
BEDROCK PARENT MATERIAL
WHAT DO TYPES OF SOIL DEPEND ON?
WHAT DO TYPES OF SOIL DEPEND ON?
TYPE OF SOIL DEPEND ON:
PARENT MATERIAL
CLIMATE
RAIN
TEMPERATURE
SLOPE
EROSION REMOVAL OF SOIL
DEPOSITION DEPOSTING OF SOIL
Time
Amount of Humus
GIVE SOME SOIL TYPES AND THEIR DIFFERENCES.
GIVE SOME SOIL TYPES AND THEIR DIFFERENCES.
TYPE OF SOIL
PRAIRIE THICK HORIZON A
TEMPERATE MODERATE HORIZON A
DESERT THIN HORIZON A
