Weathering Flashcards
What kind of climates make the most clay during weathering?
Hot and very rainy climates
What do we call a rock that has turned completely into clay?
Saprolite
Can chemical and physical weathering occur at the same time?
Yes this is called Extreme Weathering
Rocks break down when they are exposed to the weather at the Earth’s surface
Weathering
Physical change (no chemistry involved)
Mechanical Weathering
Breaking rocks apart into smaller pieces without changing the chemical composition
Sediment
What can sediment be moved by?
Wind Water Ice Gravity (ALWAYS VISIBLE)
What are the Mechanical Weathering Agents?
Extreme Heat (forest fires)
Frost Wedging
Plant Roots
Sand Blasting
What is the most powerful form of physical weathering?
Frost Wedging
Liquid water can totally fill cracks
Water expands as it freezes
Cracks are pushed further apart
Water melts and fills the larger crack
Freeze-Thaw Cycle
A chemical change in the rock’s composition
Chemical Weathering
Weathering rocks can either:
- ) Dissolve into invisible salts which late PRECIPITATE out
- ) Form new minerals as the rock breaks down, which travel as visible SEDIMENT
What are the Chemical Weathering Agents?
Water (dissolution)
Water (hydrolysis)
Oxygen (oxidation)
Oxygen (limonite or rust)
When water dissolves away
Dissolution
When water combines with rock
Hydrolysis
