The Earth's interior is composed of four layers, three solid and one liquid—not magma but molten metal, nearly as hot as the surface of the sun. The deepest layer is a solid iron ball ...

The first step toward learning about plate tectonics is to learn about the Earth's interior structure. This lesson should address both of these topics. This activity is designed for one 1-hour ...

Many geologists attribute the great variation in the temperature gradient to complex irregularities in the structure of the earth's crust. Some even maintain that the interior of the earth is cold ...

How do scientists explore Earth's hidden interior — its crust, mantle, and core? The answer lies in earthquake waves. Like X-rays, these seismic waves travel through and reflect off internal ...

Beneath the American Midwest, on the continent of North America, the underside of Earth's crust is dripping into the ...