Changing Earth

1
Changing Earths Surface

• Chapter 9, Section 6
• Deformation a change in the rocks shape or
  volume
• Stress forms 3 types of forces that cause
  deformation.

2
1 - Shearing

• Rock masses slip past each other. This creates a
  strike slip fault.

3
2 - Tension

• Rock masses streeeettch. This creates a normal
  fault. In a normal fault the hanging wall
  slides down the foot wall.

4
3 - Compression

• Rock masses collide, creating a Reverse fault.
  In a reverse fault the hanging wall slides up the
  foot wall.

5
Types of Faults

• Demo
• http//www.wwnorton.com/college/geo/egeo/animation
  s/ch8.htm
• http//www.classzone.com/books/earth_science/terc/
  content/visualizations/es1103/es1103page01.cfm?cha
  pter_no11

6
Mountain Building

• Mountains are built by
• Folding which occurs when continental plates
  collide and fold upwards. http//www.wwnorton.com/
  college/geo/egeo/animations/ch9.htm
• Faulting - can occur due to tension or
  compression along a fault line.
• Volcanoes form.

7
Land Subsidence

• When land s
• i
• n
• k
• s
• - due to geologic processes such as tension at
  divergent boundaries, or human activities such as
  building.

8
Volcanic Activity

• Most volcanoes form at plate boundariesdivergent
  or convergent.
• Hot Spot Volcanoes these form where magma melts
  its way up through the crust.
• The Hawaiian Islands were formed this way.
• http//www.wwnorton.com/college/geo/egeo/animation
  s/ch2.htm

9
This concludes Chapter 9