The layers inside the Earth

Grade 6 Science Worksheet

Circle the best answer.

1. 1.

   Bo compares two layers. Which is hotter: the mantle or the inner core?

   • The mantle, since it is closer to the Sun
   • The inner core, since heat rises with depth
   • Both the same, since deep rock heats up evenly everywhere
   • The mantle, since it is made of lava
2. 2.

   USGS says the core is nearly twice as dense as the mantle. Which reason does Esme give?

   • It is a liquid ocean of heavy lava
   • A drill sample from the core was weighed
   • It is iron and nickel metal under great pressure
   • It is cooler down there, so it packs together tighter
3. 3.

   Temperature, pressure, density. Temperature, pressure and density all change as you go deeper. Which pattern does Jun find in the USGS notes?

   • All three increase with depth
   • They peak in the mantle, then fall
   • Only temperature increases with depth
   • All three decrease with depth
4. 4.

   The crust is about 5 km thick under oceans and about 30 km under continents. Where is it thickest, by Kira's reading?

   • Under big mountain ranges, up to about 100 km
   • The same everywhere, about 30 km
   • Under the oceans, since water adds weight
   • Under flat farmland
5. 5.

   “Cross-section, not to scale:” Earth's plates are made of the crust plus the stiff top of the mantle. What is that rigid layer called, in Milo's notes?

   • The lithosphere
   • The outer core
   • The inner core
   • The asthenosphere
7. 6.

   USGS compares the Earth to a boiled egg. In that model, which part of the egg stands for the crust, by Noah's matching?

   • The thin shell
   • The whole egg, since the crust is thick
   • The yolk
   • The white
8. 7.

   In the egg model, the egg white stands for the mantle. In which way is the white a good match, says Ren?

   Use the picture in question 6.

   • It is runny and liquid, the way a lava ocean would be
   • It is the thinnest part
   • It is a thick layer between the shell and the yolk
   • It is the hottest part
10. 8.

    Tala makes a ball model of Earth about 13 cm wide, so 1 cm stands for about 1,000 km. About how thick is the 30 km continental crust on it?

    • About 3 cm
    • About 30 cm
    • About 3 mm
    • About 0.3 mm
11. 9.

    On the same ball model, 1 cm stands for about 1,000 km. About how thick should Zee make the 2,900 km mantle?

    Use the picture in question 8.

    • About 0.29 cm
    • About 0.3 mm
    • About 29 cm
    • About 2.9 cm
12. 10.

    The deepest hole ever drilled is about 12 km (USGS). On the ball model, where 1 cm stands for about 1,000 km, how deep does Ari draw it?

    Use the picture in question 8.

    • Down to the core
    • About 12 cm, nearly across the whole ball
    • About 1.2 cm, well into the mantle
    • About 0.12 mm, not even through the crust