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?

   • Both the same, since deep rock heats up evenly everywhere
   • The inner core, since heat rises with depth
   • The mantle, since it is made of lava
   • The mantle, since it is closer to the Sun
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
   • It is iron and nickel metal under great pressure
   • A drill sample from the core was weighed
   • 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 decrease with depth
   • They peak in the mantle, then fall
   • All three increase with depth
   • Only temperature increases 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
   • Under the oceans, since water adds weight
   • The same everywhere, about 30 km
   • Under flat farmland

5. Read this first

   Use this

   Cross-section, not to scale:

6. 5.

   Luz reads that the crust under the open Pacific Ocean floor, far from any island, is only about 5 km thick. What does that show?

   • Ocean crust is much thinner than continental crust
   • Ocean crust is thicker than the crust under continents
   • The crust is the thickest layer anyway
   • The Pacific floor sits right on top of the core
7. 6.

   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 inner core
   • The asthenosphere
   • The lithosphere
   • The outer core
8. 7.

   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 yolk
   • The white
   • The whole egg, since the crust is thick
   • The thin shell
9. 8.

   Drawing of a boiled egg cut in half beside a cutaway of the Earth, not to scale. USGS says the core is unlike an egg yolk in one way. Which difference does Pia find?

   • The core is cooler than the mantle
   • The core is made of stone, just like the mantle is
   • The core is the thinnest layer
   • The core has two parts, one liquid and one solid
10. 9.

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

    • It is runny and liquid, the way a lava ocean would be
    • It is the hottest part
    • It is the thinnest part
    • It is a thick layer between the shell and the yolk
11. 10.

    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 0.3 mm
    • About 30 cm
    • About 3 mm
    • About 3 cm