Crust, mantle and core

Crust, mantle and core

Fig. 4.1 . A relatively thin, rocky crust covers a thick silicate mantle. They overlie a liquid outer core, composed mainly of molten iron, and an inner core of solid iron. These nested layers have been inferred from seismic waves that travel through the Earth, changing velocity and direction at the layer boundaries.

Copyright 2010, Professor Kenneth R. Lang, Tufts University