Part 1

Exploration Phase

1. You may wish to introduce this activity by asking students:

   1. Can you name a famous fault?
   2. What happens when giant fractures develop on the Earth and the pieces move relative to one another?

2. Illustrate compressive earth movements using a large sponge by squeezing from both sides, causing uplift. Using a piece of latex rubber with a wide mark drawn on it, illustrate earth tension, by pulling the ends of the latex to show stretching and thinning.

3. Have students construct a fault model using the Fault Model Sheet. Instructions to students:

4. Color the fault model that is included according to the color key provided.

   1. Paste or glue the fault model onto a piece of construction paper.
   2. Cut out the fault model and fold each side down to form a box with the drawn features on top.
   3. Tape or glue the corners together. This box is a three dimensional model of the top layers of the Earth's crust.
   4. The dashed lines on your model represent a fault. Carefully cut along the dashed lines. You will end up with two pieces. You may wish to have your students tape or glue a piece of construction paper on the side of the two fault blocks along the fault face. This will help with the demonstration.

   Note that an enlarged version of the fault block model can be made for classroom demonstrations.

5. Have students develop a model of a normal fault.

   1. Instructions to students: Locate points A and B on your model. Move point B so that it is next to Point A. Observe your model from the side (its cross-section). Have students draw the normal fault as represented by the model they have just constructed.

Concept Development

1. Ask the following questions:

   1. Which way did point B move relative to point A?
   2. What happened to rock layers X, Y and Z?
   3. Are the rock layers still continuous?
   4. What likely happened to the river? the road? the railroad tracks?
   5. Is this type of fault caused by tension, compression or shearing?

2. Explain that this type of fault is known as a normal fault.

3. Have students label their drawing "normal fault".

4. Many normal faults are found in Nevada. This is because Nevada is located in a region called the Basin and Range Province where the lithosphere is stretching.