Pages for this activity: General directions, surface processes experiment, moons, impact experiment.

Surface processes:

Examine the effects of various processes on a surface. Use a crater or cratered surface as a sample on which to see the effects. The simulations are fairly crude, so your observations can be mostly descriptive.

  1. Preliminary: Look at images of the Jovian moons. What features do you see? Use these to predict the order of the moons, closest to farthest from Jupiter.
  2. Set-up: Remove a cup or so of flour from the bin (the precise amount is not important) and set it aside for later use. Fluff or pack the surface and coat it with colored medium. (See the general cratering directions for details if needed.)
  3. Impact cratering: Use one or more impactors to make craters. In one area of the bin, continue making craters until you pass the "saturation" level. Unsaturated is when there is uncratered (or original) surface showing, perhaps between craters. Saturation is when the surface is so cratered that new impacts don't change the amount of area covered by craters, but only rearrange the details. About how many craters are there in a given area (such as 10 cm2)? Add some details to your description.
  4. Volcanism: Add a light sprinkling of color to the cratered surface so you'll be able to see the changes. Simulate, in a fairly crude way, a lava flow or pyroclastic flow (ash, for example) by pouring the cup or so of flour over part of the cratered surface. What happens to the craters?
  5. Erosion: Add a light sprinkling of color to the current surface so you'll be able to see the changes. Simulate surface erosion by dragging a cloth or piece of paper (something flexible) lightly across part of the surface. (Don't use water - it won't work well in flour. Only use air motion - blowing across the surface - if you're outside or otherwise prepared for the mess.) What happens to the craters and volcanic features?
  6. Tectonics: Add a light sprinkling of color to the current surface so you'll be able to see the changes. Simulate quakes by tapping or gently shaking the bin of flour. Try several magnitudes of quakes. What happens to the previous features?
  7. Tectonics II: Can you think of a way to simulate plate tectonics or the stretching or shrinking of a surface region?
  8. Cratering II: Add a light sprinkling of color to the current surface so you'll be able to see the changes. What happens to the other features as you make craters now?
  9. Application: Re-assess the images of the four Jovian moons - now what do you see, and what order do you think they are from Jupiter? (Tidal effects from Jupiter and perhaps the other moons can produce geological activity.)