Core, Mantle, Crust

Just a further exploration and essentially breakdown of the topics introduced to us today.


































Interior Properties of Earth
Property: Crust Mantle Core
Fraction of Earth: <1% ∼70% ∼30%
State: “Broken rock” Plastic (Semi-)liquid
Depth (kilometers): 0–30 30–3030 3030–6370
Density (g/cubic cm): 2.7 3.5–5.5 10–12
Chemical composition: SiO2 (Fe,Mg)SiO4 Fe, Ni
Temperature (Kelvin): 300–500 500–3,000 3,000–5,300
Pressure (atmospheres): 1–1,000 103–106 106–107


Seismic waves are waves of energy caused either by earthquakes, or by massive manmade explosions. Scientists are able to measure these waves as they pass through the Earth. As these waves encounter different materials, they change in important ways, becoming longer, shorter, faster, or slower. Geologists study these changes in the waves, and are able to draw conclusions about what the core of the Earth must look like.Also, geologists also can learn a lot about the core of our planet by looking at Earth’s magnetic field.
The first layer consists of about 10 miles of rock and loose materials, scientists call the crust. Underneath the continents, the crust is almost three times as thick, as it is under the oceans.
The mantle extends to a depth of approximately 1,800 miles, as is made of a thick solid rocky substance that represents about 85% of the total weight and mass of the Earth. The first 50 miles of the mantle are believed to consist of very hard rigid rock. The next 150 miles or so is believed to be super-heated solid rock, that due to the heat energy is very weak.
It is believed that the outer core is made up of super-heated liquid molten lava. This lava is believed to be mostly iron, and nickel.It is believed that this inner core is a solid ball of mostly iron, and nickel.