Geology Squeeze Box (Denise Randol)

Materials needed

• road cut photo

• a Squeeze Box

• dirt/soil

• diatomaceous earth

• dark clay (not modeling clay)

• sand- two different colors

• water

• graph paper

• protractor

• ruler

Procedure

1. Analyze road cut photo, using Pre Lab Analysis Survey to give first impressions.

Road Cut Analysis Spreadsheet

2. Pull plunger to one end of box, leaving as much space as possible.

3. Put 1cm layers into squeeze box in the following sequence:

1. sand

2. clay

3. diatomaceous earth

4. clay

5. sand

6. soil

4. Apply a light amount of water, enough to dampen the layers- do not overwater.

5. Wait approx. 5- 10 minutes for layers to harden.

6. While waiting, sketch the side view of layers, give layers an identifying label or initial.

7. Holding box with one hand, firmly and slowly push the plunger into the layers until they are uplifted to top of box.

8. Sketch new side view, label the layers.

9. Using a protractor, theymeasure the change in angle of the layers.

10. Complete Post Lab Analysis Survey

Post Lab Analysis Survey

Explanation

The squeeze box models the structural changes to layers of rock strata when acted upon by compressional forces.

During the lab, the students simulate the formation of sedimentary rock layers. They document the layers before compression on graph paper, labeling each. As they apply compression, they observe the effects upon the horizontal layers. They illustrate the post compression view of the layers, identifying anticline and syncline deformities.

The layers represent:

1st: deposition of sand near the ocean

2nd: deposition of clay (mud) over the sand, as flooding or oceans rise.

3rd: deposition of diatomaceous earth in deeper waters (deposits of dead phyto plankton)

4th: Ocean retreats, and produces more mud layers, with deposition from river outflows.

5th: Ocean continues to retreat, water line lowers back to original shoreline and sand is deposited again.

The compression of the plunger in the box represents the plate movement against the rock layers. When rock layers are compressed, the layers are uplifted into mountains and hills. Anticlines and synclines are formed, and some more brittle rock is broken and faulted.

An anticline and syncline is a downward dip in rock strata and an anticline is an upward fold. Over thousands of years the compression, stretching and faulting from movement, deforms the rock strata. The amount of deformation is affected by the hardness and brittleness of the rock layers.

Questions

1. Why are some of the layers breaking and uplifting and others bending?

2. Which layer did you notice had the most deformity?

3. Why do you think the layers are different colors and thicknesses?

Everyday examples of the principles illustrated

Road cuts- roads constructed through hillsides by cutting vertical walls, revealing the interior layers of hill.

Front end of a car in a major collision will show same kind of buckling and bending of hood and body of car.

A simple model of deformity of layers: Put layers of blankets of different weights on a bed. Push against layers from one end- it will push up the blankets into bumps resembling anticlines and synclines.

Photos: Student Squeeze Boxes after compression

Movies

Include movies that you have taken. Your movies should be placed in your youtube account.

References

Mountain Formation

Watch Know Learn Mountain Building video