The Earth's interior can be divided up into a number of distinct geological layers. Each layer, or stratum, has distinct properties inherent to that layer. Besides the depth of each layer, Wolfram|Alpha lets you examine the density, pressure, bulk and rigidity moduli, as well as the P-wave and S-wave velocities in the corresponding layer. The crust, mantle and core are the most familiar layers, but these can be broken down into even finer strata, such as the lithosphere, asthenosphere, inner core, outer core, and upper and lower mantle.
Reference geological layers by name or by specifying a depth below the Earth's surface.