Tomography? How do we know what is below our feet?

Barbara Graham
College Southern Nevada
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A short Powerpoint presentation that introduces seismic topography to begin understanding how scientists infer the interior of the earth. Followed with a crossword puzzle to encourage vocabulary.

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Undergraduate, non-science majors. K - 12 elem education majors.

Skills and concepts that students must have mastered

How the activity is situated in the course

After an introduction to the way we used to think of the earth (onion) and now with technology the more detailed understanding of the interior..I want students to realize the evolution of science with technology, data and rigor.


Content/concepts goals for this activity

  1. basic seismicity
  2. frequency and time
  3. complexity of the interior of the earth

Higher order thinking skills goals for this activity

The goal of this activity is to get students to think beyond the textbook representation of the interior of the earth.. That it is not as simple as an onion composed of four layers.. That there are mechanics at work beneath the earth that are very complex. I would also like for students to think about what other complex systems are outside of the earth.. such as weather, climate and the oceans. What are the similarities and differences between these systems and how do they interact with one another, and do they. Trying to get away from teaching about the earth as separate systems.. as so many textbooks seem to present. Interactions and interrelationships are what creates this dynamic earth.

Other skills goals for this activity

scale, spatial referencing and relationships between surface and subsurface

Description of the activity/assignment

PPT with frequent side activities Deep Earth PPT (PowerPoint 2007 (.pptx) 3.1MB Feb24 10)

Determining whether students have met the goals

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