Question

earths layers foldable question sheet
name ____ block ____
directions: use your earths layers foldable to answer these questions. you may also need to use your textbook.

1. the planet we call earth has how many main layers? ____________

write them in order from the center to the outside of the planet.
____________________
____________________
____________________
____________________

1. use your foldable to answer these questions:

name the thickest layer ____________
name the thinnest layer ____________
write as a fraction the relationship of the thinnest layer to the thickest layer. show your work!
challenge: perhaps you have imagined digging a tunnel through the earth that comes out the other side. figure it out... how many kilometers would you have to dig? show your work!

1. write 4 interesting facts about the earths crust.

a. ____________
b. ____________
c. ____________
d. ____________

1. the crust and the upper layer of the mantle together make up a zone of rigid, brittle rock called ____________

Explanation:

Step1: Identify Earth's layers

The Earth has 4 main layers. From the center - to the outside, they are the inner core, outer core, mantle, and crust.

Step2: Determine thickest and thinnest layers

The mantle is the thickest layer. The crust is the thinnest layer.

Step3: Calculate fraction of layer thicknesses

The average thickness of the crust is about 35 - 70 km for continental crust and 5 - 10 km for oceanic crust. Let's take an average of 20 km for crust. The mantle is about 2900 km thick. The fraction of the thickness of the crust to the mantle is $\frac{20}{2900}=\frac{1}{145}$.

Step4: Calculate tunnel length

Digging a tunnel through the Earth from one side to the other is equivalent to the diameter of the Earth. The average diameter of the Earth is about 12742 km.

Step5: List facts about Earth's crust

a. The Earth's crust is divided into continental and oceanic crust.
b. It is the source of all the minerals we mine.
c. Earthquakes occur in the crust.
d. The crust is constantly moving due to plate - tectonics.

Step6: Name the rigid zone

The crust and the upper layer of the mantle together make up a zone of rigid, brittle rock called the lithosphere.

Answer:

1. 4; inner core, outer core, mantle, crust
2. Mantle; Crust; $\frac{1}{145}$; 12742 km
3. a. The Earth's crust is divided into continental and oceanic crust.

b. It is the source of all the minerals we mine.
c. Earthquakes occur in the crust.
d. The crust is constantly moving due to plate - tectonics.

1. Lithosphere