Layer Cake Geology

Molly Ward
Museum of the Rockies (through 6/30/09)
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This activity visually introduces students to the idea of geologic time and the correlation between time, rock layers and fossils. It uses the familiar, relevant example of cake but teaches important concepts such as the Law of Superposition, and relative dating and hints at more advanced concepts such as the principle of faunal succession. This activity could also be modified and expanded to teach more in-depth paleontological topics including absolute dating and geologic mapping (as related to finding fossils).

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This activity was designed as a fun way to introduce very young students (K-5) in short informal museum classes to the concepts of geologic time, the fossil record and geologic dating. This write up of the activity was made for inclusion in a traveling teaching trunk where most materials are included. With the proper materials (a white cake with different layers colored with food coloring works, too!), this activity could be used as a demo to introduce any student unfamiliar with these ideas to the concepts.

Skills and concepts that students must have mastered

Sedimentary rock formation processes
Fossil formation (in sedimentary rocks)

How the activity is situated in the course

This is a stand alone exercise and visual that is referred to throughout the class (or period of study) as a reminder about important basic underlying geological and paleontological concepts for introductory students.


Content/concepts goals for this activity

-Sedimentary rocks form layers.
-When deposited, younger (more recent) sedimentary rock layers sit on top of older rock layers (Law of Superposition).
-Sedimentary rock layers and time can be correlated.
-Relative ages of rocks can be determined based on rock layer position.
-Relative ages of fossils within rock layers can be determined based on position.

Higher order thinking skills goals for this activity

Students must synthesize ideas about rock, a solid physical entity, representing time, an non-tangible concept. They must also use a model (layer cake) to visualize a rocks in the real world.

Other skills goals for this activity

Individual completion of concept related worksheet

Description of the activity/assignment

This activity provides young students with a relevant model (a layer cake) to help them understand concepts about sedimentary rock layers (such as the Law of Superposition), correlation of the rock record with geologic time and relative ages of rocks and fossils.

Determining whether students have met the goals

Correct completion of worksheet measures understanding of concepts addressed.

More information about assessment tools and techniques.

Teaching materials and tips

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