Monday, January 28, 2008

"Differential Erosion"

Bellwork:
•1) The 3 types of sedimentary rock are…
•2) Erosion is…
•3) ________________ eroded the rocks in the Grand Canyon.

- Observe Chuar Butte (pg. 18 in Earth History Resources) in order to complete "Chuar Butte Observations" (pg. 41 in textbook) ==> example of differential erosion
- "Differential Erosion": Happens anytime softer, weaker rocks and harder, stronger rocks are in the same place...the softer rocks erode more quickly
- Shale is a softer rock that erodes more quickly, limestone is harder and erodes more slowly
- View examples of landforms created by differential erosion on pgs. 20-21 in Earth History Resources and on Earth History CD-ROM (look under "Monument Valley Formation," username: cheetah, password: 112)
- Choose and sketch 1 landform from pgs 20-21; divide it into main sections of rock; label each section as soft or hard; infer and label each section as shale, limestone, or sandstone