Читать книгу Earth Materials - John O'Brien - Страница 17

The layers within Earth that are defined largely on the basis of chemical composition (Figure 1.1; left side) include the: (1) crust, which is subdivided into continental and oceanic crust, (2) mantle, and (3) core. Each of these layers has a distinctive combination of chemical, mineral, and rock compositions that distinguishes it from the others, as described in the next section. The thin crust typically ranges from 5 to 85 km thick and occupies <1% of Earth's volume. The much thicker mantle has an average radius of ~2885 km and occupies ~83% of Earth's volume. The core has a radius of ~3470 km and comprises ~16% of Earth's volume.