Home | Session 2 | Faults 1, 2, 3, 4, 5

Faults: A USGS Teacher's Lesson

Application Phase

1. Explain that faults are often (but not always) found near plate boundaries and that each type of fault is frequently associated with specific types of plate movements. However, all types of faults can be found at each type of plate boundary.

   a. Normal faults are often associated with divergent (tensional) boundaries.

   b. Thrust faults are often associated with convergent (compressional) boundaries.

   c. Strike-slip faults are often associated with transform (sliding) boundaries.

2. Ask the following questions:

   a. What kind of faults would you expect to find in the Himalayas (hih-MAHL-yuz)? Why?

   b. What kind of faults would you expect to find along the Mid-Atlantic Ridge? Why?

   c. Is California likely to "fall into the Pacific Ocean?" Why or why not?

3. Explain that not all faults are associated with plate boundaries. Explain that there is a broad range of faults based on type, displacement, age, current or historical activity, and location on contintental or oceanic crust. Have students research examples of faults that are not at plate boundaries.
4. Explain to students that the stresses and strains in the earth's upper layers are induced by many causes: thermal expansion and contraction, gravitational forces, solid-earth tidal forces, specific volume changes because of mineral phase transitions, etc. Faulting is one of the various manners of mechanical adjustment or release of such stress and strain.
5. Have students research and report on the types of faults found in your state.

Extensions

1. Have students identify the fault movements in the recent Loma Prieta, California earthquake.
2. Have students research the fault histories and recent theories concerning earthquakes in Northridge, California (1994), New Madrid, Missouri (1811-12), and Anchorage, Alaska (1994).

Coloring Key:

Rock Layer X - green
Rock Layer Y - yellow
Rock Layer Z - red
River - blue
Road - black
Railroad tracks - brown
Grass - green

Top

updated January 28, 2002

UCMP Home  |   What's new  |   About UCMP  |   History of Life  |   Collections  |   Subway