Transcript Slide 1

Layers of the Earth
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2.
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6.
7.
Crust
Upper Mantel
Transition Region
Lower Mantel
“D” layer
Outer Core
Inner Core
http://www.youtube.com/watch?v=3xLiOFjemWQ&feature=related
Inner Core
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5150-6378 kilometers
4300 degrees C
Iron
Is unattached to the mantle, being suspended by the molten outer
core.
This field is also known as Earth's magnetic field, which is
responsible for the functioning of mechanical and biological
compasses.
This field also causes a subtle jerking motion in the Earth's daily
rotation.
About 10% of this layer is composed of sulfur and/or oxygen due
to the fact that these two elements are abundant in the cosmos
and dissolve readily in molten iron.
Outer Core
2890-5150 kilometers
 The inner core is composed mostly of iron
(Fe) and is so hot that the outer core is
molten, with about 10% sulphur
 represents about 4% of the mantle-crust
mass.
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“D” layer
The D" layer of Earth is about 3% of
Earth's mass
 is 125 to 188 miles (200 to 300 kilometers)
thick and covers about 4% of the mantlecrust mass.
 This layer, in terms of whether it is part of
the lower mantle or an independent layer
is still somewhat unclear.
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Lower Mantel
Most of the Earth's mass is in the mantle.
 1000 degrees C, the mantle is solid but
can deform slowly in a plastic manner.
 Two layers
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lower mantle~ includes silicon, magnesium,
oxygen, some iron, calcium, and aluminum.
This layer is comprised of 72.9% of the
mantle-crust mass.
Transition region
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7.5% of Earth's mass
a depth of 250-406 miles (400-650 kilometers).
This layer is also known as the mesosphere and
is 11.1% of the mantle-crust.
It is made of mainly basaltic magmas with
amounts of calcium, aluminum and garnet (an
aluminum-bearing silicate mineral).
The layer becomes dense when the garnet
mineral cools but is buoyant and light when
subject to heat due to the low melting points.
Mantel
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Most of the Earth's mass is in the mantle.
1000 degrees C, the mantle is solid but can
deform slowly in a plastic manner.
Two layers
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upper mantle~ this part of the crust composes of
15.3% of the total mantle-crust mass and is made of
crystalline forms of Olivine (Mg,Fe)2SiO4 and
pyroxene (Mg,Fe)SiO3. The upper mantle makes up
10.3% of the Earth's mass, extending a depth of 6250 miles (10-400 kilometers).
Crust
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0-40 kilometers
O degrees C
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The outer most layer, the crust, is categorized into two parts,
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the Oceanic crust and the continental crust.
 The Oceanic crust is the smallest part of Earth, only 0.099% of its mass and
reaching a small depth of 0-6 miles (0-10 kilometers. The ocean floor is
covered in basalt originating from volcanic activity.
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Continental crust: The second smallest area of the Earth making up only
0.374% of the Earth's mass and extending a short depth of 0 - 31 miles (050 kilometers). Looking at the percent by composition, the continental crust
makes up only 0.554% of the mantle-crust mass. The layer is composed
primarily of crystalline rocks made of low-density buoyant minerals
dominated mostly by quartz (SiO2) and feldspars (metal-poor silicates). This
is the outer part of the Earth composed essentially of crystalline rocks.
Bringing it all together
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http://www.youtube.com/watch?v=a2HliYJOzuE&feature=related
Sources
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1.
http://www.seismo.unr.edu/ftp/pub/louie/c
lass/100/interior.html
http://library.thinkquest.org/28327/html/un
iverse/solar_system/planets/earth/interior
/layers_of_earth.html
science.pppst.com/layers.html