Geologic Time Scale

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Across
  1. 2. The process of breaking down or decomposing.
  2. 3. The time taken for the radioactivity of an isotope to decrease to half its original value.
  3. 4. A living thing or life form.
  4. 6. The time before humans began documenting history.
  5. 9. The law of relative dating that states any geological feature that cuts through a rock layer is younger than the rock layer it disrupted.
  6. 10. The most recent geological eon that we currently living in.
Down
  1. 1. The law of relative dating that states a rock layer underneath another is older than the top layer.
  2. 5. A scientist who studies earth that what it’s made up of.
  3. 7. The law of relative dating that states that any rock fragment inside another must be older than the rock it is a part of.
  4. 8. Remains or imprints of an organism found in rocks