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Formation of Sedimentary Rocks


sand-can be seen with the eye
silt-grains visible with a magnifying glass
clay-cant be seen with the eye or magnifying glass

Scientific Method

1. Problem/Purpose/Question:

How do sedimentary rocks form?

2. Hypothesis:

If we mix the 3 grains together, it will all morph together into visible layers. The sand will probably be at the bottom (because it's the heaviest), the silt in the middle (small, but not as small as clay), and the clay on the top.

3. Materials:

  • water (precise measurement not given)
  • stir stick
  • magnifying glass
  • paper towels
  • 3 little cups (with grains: sand, silt, clay)
  • 1 large plastic cup

4. Procedure

  1. Collect all the grain samples and oberve. What does it look like?
  2. Pour all grain samples into the large plastic cup
  3. add water to the plastic cup
  4. stir
  5. let it dry
  6. observe

5. Data/Observations

  • sand- rough, varioius colors (red, black, grey, tan)
  • silt-clear, white, like little beads
  • clay- powder, white, dissolves very quickly