Download Notes!

The Layers of the Earth
The Five Structural
Layers
The Earth is composed of five
structural layers. The
lithosphere is the layer that
you live on, and it is the most
widely studied and understood.
The asthenosphere is much
hotter and has the ability to
flow, like oobleck. The
mesosphere is even hotter
than the asthenosphere!
Finally, the inner and outer
core are extremely hot with
pressures so great you would
be squeezed into a ball smaller
than a marble if you were able
to go to the center of the Earth!
The Lithosphere
The lithosphere is made up of
the crust and upper mantle
of the Earth.
There are actually two different
types of crust-Continental &
Oceanic! Continental crust
is made of granite, while
oceanic is made of basalt.
(That is pretty important.
You should remember it.)
The lithosphere is Earth’s hard
outer shell, which make
sense when you know that
“Litho” means ROCK!
The Lithospheric Plates
• The lithosphere of the Earth is broken into many pieces called
tectonic plates. The plates "float" on the soft, semi-rigid
asthenosphere.
• Some plates hold mostly oceans, some hold mostly landmasses,
and some hold both. Compare the Pacific Plate and the South
American Plate. What does each one hold?
The Asthenosphere
The asthenosphere is the part of the upper
mantle that flows like ooblek. Convection
currents are found here that move the tectonic
plates!
The Mesosphere
The Mesosphere makes up the
lower mantle.
It is more solid than the
asthenosphere, probably due to
pressure.
Temperatures here reach over
2205 degrees Celsius! That is
over 4000 degrees Farenheit.
The Outer Core
The core of the Earth is like
a ball of very hot metals.
The outer core is so
hot that the metals in it
are all in the liquid state.
The outer core is
composed of the melted
metals of nickel and
iron.
It is 2200 km thick
Temperatures range from
2205 degrees C to 4983
degrees C
The Inner Core
The inner core of the
Earth has temperatures
and pressures so great
that the metals are
squeezed together and
are not able to move
about like a liquid, but
are forced to vibrate in
place like a solid.
The inner core is 1250km
thick
The End
Writing Prompt: Pretend you are in a vehicle that will
burrow down to the center of the Earth. Describe your
journey though the structural layers. What do you see? How
does the temperature change?