Layers of the Earth—How were they found? What are they?
From IRIS' Education & Public Outreach. 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. .
