Internal Layers of the Earth: Crust, Mantle, Core

Internal Layers of the Earth

1. The Earth’s
Layers

2. Objective:
•Identify the
characteristics of the
Earth's layers.

5. Crust
•The crust is the
layer that you live on
so it is the most
widely studied and
understood.

6. * The Earth’s crust is very thin
compared to the other three
layers.
*The crust makes up 1% of
the Earth.
* The crust of the Earth is
broken into many pieces
called plates.

7. What are Plates?
•Continent-sized slabs that make
up the crust and the mantle
•Plates are constantly moving,
very slowly

8. Plates Move:
•Away from each
other
•Toward each other
•Past each other

9. When Plates Move Together
•Mountains or Volcanoes are
formed

10. When Plates Move Past
Each Other
•Earthquakes occur

11. •The pressure
builds and causes
an Earthquake as
rocks break and
crack.

12. •The plates move along smoothly
but sometimes they get stuck and
pressure builds up.

13. TWO TYPES OF CRUST
–Oceanic Crust(very
dense, made of basalt)
–Continental Crust
(less dense, made of
granite)

14. •Made up of large amounts
of silicon and aluminum
•Composed of plates on
which the continents and
oceans rest
Ocean Land

15. •The crust is only about 3-5
miles (8 kilometers) thick
under the oceans(oceanic
crust) and about 25 miles
(32 kilometers) thick under
the continents (continental
crust).

17. Physical Structure of the
Earth
•Lithosphere-rigid outer
layer (crust)
•Asthenosphere-solid
rock that flows slowly
(like hot asphalt)

18. LITHOSPHERE
•The lithosphere (geosphere) is the
"solid" part of Earth. It has two parts,
the crust and the upper mantle
•The lithosphere “ sits on the”
asthenosphere.
•The Earths Plates are the lithosphere.
•It is the rocky, solid portion of the
crust. Remember that it is made up of
mostly Silicon( Si) and Oxygen (O).

19. ASTHENOSPHERE
•This is the layer below the
lithosphere. This layer is “ plastic
–like”.
•It is somewhat solid/liquid.
•You can say that it is malleable.
•Very important in terms of plate
tectonics.

21. TECTONIC PLATES
•Earth’s crust is broken into about 19
pieces
•These plates move on top of the
asthenosphere

22. Mantle
•The mantle is the largest layer of
the Earth.
•It is made of hot, dense rock. The
rock in the mantle flows like
asphalt because of the temperature
differences found in the mantle.

23. Mantle
•The movement
of the mantle
create the
movement of
the Earth’s
plates.

24. •Solid but capable of flow (like
hot asphalt or fudge)
•Thickest layer of the Earth
(making up 70% of the Earth’s
mass)
Upper Mantle
Convection
Currents
Middle
Mantle
Lower Mantle

25. •The hot material (magma) in
the mantle rises to the top
of the mantle, cools, then
sinks, reheats, and rises
again. These convection
currents cause changes in
the Earth’s surface

26. Core
•The core of the Earth is
much like a ball of very
hot metals.The inner core
is surrounded by a fluid
iron outer core.

27. Outer Core
•Molten (liquid) metal that is
about 4,700°C (8,500°F)
•Located about 1,800 miles
beneath the crust and is about
1,400 miles thick
•Composed of the melted
metals nickel and iron

28. Inner Core
•Solid sphere composed mostly of iron
•Its temperature is 6,650°C (12,000°F)
which is as hot as the Sun
•It is solid because of the pressure
from the outer core, mantle, and crust
compressing it tremendously

29. •Temperature
increases as depth increases

30. Density and Pressure
increase as depth increase

31. •Which layer of the
Earth has the greatest
temperature,
pressure, and
density?

32. Core