Brittle Vs. Ductile: Big Hunk as a Model for Earth's Crust & Mantle

3min 25s Novice

How can we model ductile rocks in the classroom?

Video lecture on how temperature controls mechanical behavior of materials, including rocks. A Big Hunk candy bar is used as a model for the behavior of materials in the lower lithosphere. The cold candy bar is brittle while the warm candy bar is ductile or plastic.

Dr. Robert Butler, University of Portland, OR shows that a material can be either ductile or brittle; temperature can control the mechanical behavior of a material; and a Big Hunk candy bar can be used as a model for the lithosphere



  • What is the difference between brittle and ductile?
  • How can a chewy candy represent the crust and the asthenosphere?
  • Does ductile material have earthquakes?
  • Why doesn’t the asthenosphere have earthquakes?
  • What happens when stress is applied to ductile materials?
  • What happens when stress is applied to brittle materials?

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