## Earth's Layers

### Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
Two main ways scientists collect information about the Earth is by into it and by using information.
equipment measures the seismic or shockwaves produced by .
The hole on earth is or 40,000 feet deep.
A is used to study parts of science where the real object be studied.
Earth is made of layers; the , the , and the .
All life exists either on the or within the first few meters of the crust.
The layer of the Earth is called the .
We have been able to dig a hole the crust.
The is made up of different kinds of rock, but the two main types are and .
is much than granite. crust is made only of .
elements make up more than of the crust; oxygen, silicon, aluminum, iron, and calcium.
Another name for the is the , the portion of the Earth.
The scientists believe that Earth’s crust, or , is into several segments or .
The Earth’s surface can be divided into kinds of , crust and crust.
crust is found under the landforms or and is usually about thick; however, it may be up to thick in areas.
The part of crust is made up of and the part is .
The of the goes from Celsius at the surface to Celsius at the bottom.
crust is much than continental crust. It averages only thick.
crust is only made of which is much and than continental crust.
The Earth has a very thin or layer the and the mantle called the Mohorovicic Discontinuity or .
The is sort of like a between the and the .
The is the layer of the Earth and it is the .
The makes up of the Earth’s total volume and 68% of it’s MASS!!!
The has a lot than the crust and the amount of iron as you go .
The part of the is soft and gooey and is called the . The sort of on top of the asthenosphere.
At the top of the , the averages about and near the bottom it reaches .
The is really , an core and an core.
The core is believed to be deep. The goes from on the upper edge and gets hotter the deeper you go, up to .
The core is , very dense melted iron and nickel.
The core is believed to be 1,300 kilometers in depth. are believed to be about throughout.
The is iron and nickel. It is solid because of the incredible on it.