Download The Earth Inside Outside and Above

By : Barbara and Sarah
How were the Continents Formed?
• Tectonic plates carried a number of land masses together to
form a single continent, called Pangaea, which was
surrounded by an ocean called Panthalassa. Then, beginning
about 200 million years ago, Pangaea broke apart into the
northern continent of Laurasia and the southern continent
of Gondwanaland. The modern basins of the Pacific,
Atlantic, and Indian oceans began to take shape about 120
million years ago, when Laurasia broke apart into Eurasia
and North America, while Gondwanaland split into Africa,
Antarctica, Australia, India, and South America.
The Earth’s crust
• Just under the earth’s crust are thick layers of
hot rock, this hot rock surrounds a ball of
mostly hard metal at the center of the earth.
Earth has three layers of hot rock and metal.
All dry land and ocean floors are a part of the
earths crust too. Earth’s crust is like a hot
rocky shell. The crust is about 25 miles and 40
kilometers thick.
The Troposphere and the
Stratosphere
Troposphere
Stratosphere
• The troposphere helps
maintain the
temperatures on the
earth’s surface it allows
sunlight to pass
through the other
layers. This layer of the
atmosphere moves.
• The stratosphere
begins six miles above
the earth’s surface.
The stratosphere is
nearly cloudless and
really dry except there
are ice clouds during
the winter. This layer
of the atmosphere is
still.
The Mesosphere and the
Thermosphere
Mesosphere
Thermosphere
• The lowest
temperatures occur in
earth’s atmosphere is
the mesosphere. The
mesosphere gets the
coldest in the summer
because winds and
storms cause waves of
air to form in the
troposphere.
The air is extremely thin
in the thermosphere;
the thermosphere
contains mostly
hydrogen and helium.
Daily and seasonal
changes in the solar
activity causes the
temperatures in the
thermosphere to vary.
The Exosphere
• The exosphere is 341 to 434 miles above the
earth. The exosphere is made up of mostly
hydrogen. Artificial satellites generally orbit in
this region.
urbanext.illinois.edu
k12tlc.net
gkbasic.com
scienceclarified.com
esrtx.english-ch.com.
tx.english-ch.com
Credits
Dutch, Steven I. "Earth." World Book Student. World Book,
2012. Web. 26 Oct. 2012.
Moran, Joseph M. "Troposphere." World Book Student. World Book,
2012. Web. 26 Oct. 2012.
Ramanathan, Veerabhadran. "Stratosphere." World Book Student. World
Book, 2012. Web. 26 Oct. 2012.
Hitchman, Matthew H. "Mesosphere." World Book Student. World Book,
2012. Web. 26 Oct. 2012.
Moran, Joseph M. "Thermosphere." World Book Student. World Book,
2012. Web. 26 Oct. 2012.
Crust." World Book Kids World Book, 2012. Web. 26 Oct. 2012.
http://www.reference.com/browse/Exosphere