university of haripur, geology

1. Types of Weathering
Kim Bennison
Katy Hogan
Alex Gage
Kelly Fischer

2. Mechanical/Physical Weathering
• Exfoliation
• Ice Wedging
• Organic Wedging
• Abrasion

3. Exfoliation
When a rock has heat exerted upon it,
along with pressure, it separates into
layers.

4. Ice Wedging
When water leaks into the cracks of rocks,
it freezes and causes the rock to crack.

5. Organic Activity
This occurs when burrowing animals,
humans, or plants interfere and work their
way into rocks.

6. Abrasion
Abrasion occurs when rocks rub against
eachother and become rounded.

7. Chemical Weathering
• Hydrolysis
• Oxidation
• Dissolution
• Acid
– Carbonation
– Precipitation
– Plant Acid

8. Hydrolysis
When rocks sit in water for extended
periods of time they begin to break down
and have a clay-like texture.

9. Oxidation
When oxygen reacts with iron in rocks, they
rust, taking on a red-orange color.

10. Dissolution
Rocks, when in water, react with acids in
the water and dissolve. A clue that this
has happened to a rock is the presence of
small holes.

11. Acid 1
• Carbonation- water absorbs carbon
dioxide when rain falls or from decaying
organic material. The carbon dioxide
dissolved in water forms carbonic acid that
reacts with many common minerals.

12. Acid 2
• Precipitation- Water in the atmosphere
absorbs sulfur oxides and nitrogen oxides.
Through a series of chemical reactions
these pollutants are converted into acids
that are a cause of acid precipitation.

13. Acid 3
• Plant Acid- When plants decay they
release acids that react with the minerals
in rocks.