Earth’s Layers

Presented by Brent Daigle, Ph.D. (ABD)

If you take an Easter egg, and dye it a swirly blue, green, and white, what would you have?

Presented by Brent Daigle, Ph.D. (ABD)

It might look like the earth, as we see it in photographs from space. Now, if you slice this little model of the earth in half, you can see the layers that it is made of.

Presented by Brent Daigle, Ph.D. (ABD)

The earth has an outside layer called the crust (the eggshell), an in-between layer called the mantle (the egg white), and an inner core (the yolk).

Presented by Brent Daigle, Ph.D. (ABD)

 Just like the hard shell of an egg, the earth's crust is hard and solid. It is mainly rock. All of the earth that we can see, and walk on, and drive our cars on, is crust.

Presented by Brent Daigle, Ph.D. (ABD)

And if you are at the beach and can't see any crust, because you are looking out at the ocean, it is still there under the water. The whole earth is coated with a thin (about 3 kilometers under the oceans, and about 19 kilometers under the land) layer of rocky crust.Presented by Brent Daigle, Ph.D. (ABD)

The earth's middle layer, the mantle, is made up of molten, or melted, rock. The lava for volcanic eruptions comes from this layer. The dividing line between the mantle and the crust has a long and hard-to-say name; it is called the "Mohorovicic Discontinuity," but scientists call it the Moho for short.

Presented by Brent Daigle, Ph.D. (ABD)

On the upper part of the mantle there are sections called tectonic plates. The seven continents sit on the top of these tectonic plates.

Presented by Brent Daigle, Ph.D. (ABD)

In 1906, the center of the earth, the core, was discovered by a scientist named R. D. Oldham. To make this discovery, he studied earthquakes, and also the ideas of a scientist from earlier times, Isaac Newton.

(building implosion of the Madison Hotel ~ Earthquakes produce similar effects)

Presented by Brent Daigle, Ph.D. (ABD)

The core consists mainly of iron, along with smaller amounts of other elements. The iron at the earth's core is partly solid, and partly liquid. Some scientists have a theory that the core is spinning on its own, much faster than the rest of the earth.

Presented by Brent Daigle, Ph.D. (ABD)

To learn about the earth's layers, scientists study earthquake waves, rock formations, and magnetism, but you can get a good picture of what they look like by studying a hard-boiled egg.

Presented by Brent Daigle, Ph.D. (ABD)