Active, Dormant & Extinct · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.
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Active, Dormant, or Extinct?

Science · Volcanoes & Earthquakes · ages 7-9
Name ______________________   Date ____________

  1. Which label means scientists do not expect another eruption?

    • Active
    • Dormant
    • Extinct

  2. A volcano is erupting now. Which label fits in this lesson?

    • Active
    • Dormant
    • Extinct

  3. A dormant volcano is quiet now, but it could erupt again someday.

    Circle one:   True   False

  4. A dormant volcano has been quiet for 100 years. Why do scientists still watch it?

    • Its quiet years prove an eruption will happen next week.
    • Its quiet years prove that no eruption can happen again.
    • Another eruption is possible after a long quiet time.

  5. A volcano has been quiet for 250 years. Scientists think it could erupt again. Which label fits this lesson?

    • Active
    • Dormant
    • Extinct

  6. A volcano has been quiet for 50 years. That fact alone proves it is extinct.

    Circle one:   True   False

  7. A volcano erupted 10 years ago and is called active. Does that label mean another eruption will happen soon?

    • Yes. Active means an eruption will happen in the next few days.
    • Yes. All active volcanoes erupt again after the same wait.
    • No. Active does not give a date for another eruption.

  8. Scientists called a volcano extinct. New evidence suggests it could erupt again. What should they do?

    • Keep the old label because it can never change.
    • Review the label using the new evidence.
    • Set the label using only the years since it last erupted.
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Active, Dormant, or Extinct? W1-mt_dSeFrAWE4v-s1

  1. Extinct · Extinct is the label used when scientists do not expect another eruption.
  2. Active · A volcano erupting now is active. Dormant describes a long quiet period, and extinct means another eruption is not expected.
  3. True · Dormant means quiet for a long time while another eruption is still possible.
  4. Another eruption is possible after a long quiet time. · A dormant volcano may erupt again. Watching for changes helps scientists judge possible danger, but quiet years do not prove safety or set an eruption date.
  5. Dormant · Dormant fits the two clues: a long quiet period and the possibility of another eruption. The number of years alone would not settle the label.
  6. False · Quiet years alone do not prove extinction. Scientists need other evidence about whether another eruption is possible.
  7. No. Active does not give a date for another eruption. · An active label does not mean an eruption will happen soon. The past eruption date does not give the date of the next one.
  8. Review the label using the new evidence. · The new evidence challenges the earlier assessment. Scientists should review the label using that evidence.
Worksheet · LightMySky