Smooth River Rock and Compilation

Small rocks have been rounded as they were carried downstream by the energy of the water and that the jagged edges are worn off from tumbling along the bottom of the stream. They were deposited in a low area within the stream and the rocks pile up in that place.

Video

Pleasantville

Iowa Core Standard

4-ESS2-1

Make observations and/or measurements to provide evidence of the effects of weathering or the rate of erosion by water, ice, wind, or vegetation

Driving Question

Why are the rocks smooth without jagged edges?

Probing Questions

Why is there a pile of rocks all in one place in the stream?

Classroom Suggestions

Students could:

Look at smooth river rocks and jagged rocks from a quarry in the classroom and determine which location they came from.

Resources

Sciencing | How are River Rocks Formed?: Photos and description of weathering of rocks in rivers.
PBS LearningMedia | 60-Second Science: Weathering Rocks: This video demonstrates why some rocks are smooth and round using plastic jars, rocks, water and a sieve.

Contributors

Submitted by Miika Busick.