The Rock Cycle · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

The Rock Cycle

Science · Matter & Materials · ages 12-14
Name ______________________   Date ____________

  1. Which rock type forms when layers of sediment get pressed together over time?

    • Metamorphic
    • Sedimentary
    • Igneous

  2. Which rock type forms when magma or lava cools and hardens?

    • Igneous
    • Sedimentary
    • Metamorphic

  3. Marble is a metamorphic rock formed from limestone that was heated and squeezed without melting.

    Circle one:   True   False

  4. A geologist finds an igneous rock with tiny, hard-to-see crystals. Where did this rock most likely cool?

    • At Earth's surface, quickly
    • Deep underground, slowly
    • Under a riverbed, from sediment

  5. Granite has large, easy-to-see crystals. What does that tell you about how it cooled?

    • It cooled quickly at the surface
    • It was never melted at all
    • It cooled slowly, deep underground

  6. Which of these is the correct order for how limestone becomes marble?

    • Limestone melts into magma, then cools into marble
    • Limestone forms from sediment, then gets buried and squeezed by heat and pressure
    • Marble forms first, then breaks down into limestone

  7. A student wants to know if a rock took millions of years to form. Which fact best shows the rock cycle works over geological time, not quickly?

    • Sediment must pile up in layers and get buried deep before enough pressure builds to form solid rock
    • Rocks change type within a few days after a rainstorm
    • Magma cools into igneous rock the instant it leaves a volcano

  8. Amir says: "Once a rock becomes metamorphic, it can never change again." What is wrong with his claim?

    • Metamorphic rocks are the last stage, so he's correct
    • Metamorphic rocks turn to sediment the instant they form
    • Metamorphic rock can still melt, weather, or be squeezed further, joining the cycle again
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Answer key

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

The Rock Cycle W1-mt_NckKLZ3uCE-s1

  1. Sedimentary · Sedimentary rocks form when loose sediment gets buried and squeezed into solid rock.
  2. Igneous · Igneous rocks form straight from cooled, melted rock.
  3. True · Heat and pressure rearranged limestone's minerals into marble, without ever turning it to liquid.
  4. At Earth's surface, quickly · Fast cooling at the surface doesn't give crystals time to grow, so they stay small.
  5. It cooled slowly, deep underground · Slow cooling underground gives crystals time to grow large, that's why granite's crystals are easy to spot.
  6. Limestone forms from sediment, then gets buried and squeezed by heat and pressure · Limestone, a sedimentary rock, turns into marble through heat and pressure, without ever melting.
  7. Sediment must pile up in layers and get buried deep before enough pressure builds to form solid rock · Building enough sediment and pressure to form rock, or squeezing rock deep underground, takes a very long stretch of geological time.
  8. Metamorphic rock can still melt, weather, or be squeezed further, joining the cycle again · The rock cycle has no final stop. Any rock, including a metamorphic one, can melt, weather, or transform again.
Worksheet · LightMySky