1. Sedimentary Processes I
By: Athena Coleen Sugui

2. Earth’s External Processes
Weathering
Weathering
Mechanical
Mass Wasting
Chemical
Erosion

3. Mechanical Weathering
Big rocks,
broken down into little pieces
Frost wedging
Salt Crystal Growth
Sheeting
Biological Activities

4. What is Frost Wedging? Salt Crystal Growth -known as Haloclasty
-disintegration of rocks
-leaves salt crystals
What is Frost Wedging?
Expands, Contracts,
Breaks
Hot days, Cold nights

5. Sheeting and Exfoliation
-Peeling off in Sheets
-Pressure-release jointing
-Thin layers
Sheeting and Exfoliation

6. Biological Weathering

7. Water and Carbonic Acid
Chemical Weathering
Water and Carbonic Acid
Hydrolysis
-CO2 reacts with water =Carbonic acid
-Attacks different kind of rocks
-leaves pockets(caves)
Spheroidal Weathering
Weathering of Granite

8. Hydrolysis -silicate minerals; altered by the process Hydrolysis
-compound reacts with water (forming
one or two substances);
-Rock forming minerals;

9. Spheroidal Weathering and Granite Weathering
-crumbled;
-Concentric shells of decayed rock (most are granite);
-loosened or separated;
-edges are rounded;
-Jointed;

10. Factors that Affect the Rate of Weathering
Climate - warmer temperature speeds up chemical reactions
- water allows molecules to move faster
Rock Composition – harder rocks (slower rate)
- soft rocks (faster rate)
Surface Area – rocks exposed (increases rate)
- less surface area (slower rate)

11. References www.sepmstrata.org/page.aspx?pageid=680 www.studyblue.com
www. Estes.on-line.com/rmnp/articles/frstwdg.html
zschierlphotography.com
teach.albion.edu
geology.about.com
Geology4kids.com
home.portervillecollege.edu
blogs.yis.ac.jp