Layers of the Earth—What are they? How were they found? (Educational)

CHAPTERS:
0:00 Intro
0:46 Seismic waves
0:57 Three layers ( like egg?)
1:56 Basic layers
2:01 Crust chemistry
2:53 Mantle chemistry
3:46 Core
4:47 crust vs. plate?
5:36 Earthquakes, volcano, magnetics

How do we know what is deep inside the Earth? And who discovered it?
The Earth has 3 main layers based on chemical composition: crust, mantle, and core. Other layers are defined by physical characteristics due to pressure and temperature changes. This animation tells how the layers were discovered, what the layers are, and a bit about how the crust differs from the tectonic (lithospheric) plates, a distinction confused by many.
Animation & graphics by Jenda Johnson, Earth Sciences Animated
Science editor Dr. Robert Butler, University of Portland
Reviewed by Dr. George Zandt, University of Arizona
Made possible by funding from the National Science Foundation
Egg analogy from Dr. Robert Butler video: Egg vs. Earth
Big Hunk© analogy from Dr. Robert Butler video: Brittle vs. Ductile
Plate-tectonics graphic: U.S. Geological Survey’s “This Dynamic Earth”
Photographs are public domain or fair use.
Music: “Streetlight On a Dark Road”, by Kevin MacLeod
Maps from Google Earth.

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