Explore Exploration Activity The compositional zones of Earth's interior are the crust, mantle, outer core, and inner core. Each zone has unique physical and structural properties. The crust is the thin, solid, outermost zone of the Earth. It is approximately 35 kilometers thick. Below the crust is the mantle. Earth's mantle is more dense and thicker than the crust. It is approximately 2,900 kilometers thick. The outer core lies beneath the mantle and is hypothesized to be liquid in composition. It is 2,250 kilometers thick. Finally, the inner core is believed to be solid and is 1,250 kilometers thick. Surface 400 km 670 km 1000- Solidus Mantie Sold 2000 - I 3000 - Temperature Met Using the diagram to the right, fill in the temperature values for the depth distances given in the table below. The first row is completed for you as an example. 4000 - Outer Core 5000 - Inner Core 6000 - 1000 2000 3000 4000 5000 Temperature (C) Zone Depth (Kilometers) Temperature ("C) Crust 1 km 25°C Mantle 1,000 km Outer Core 4,000 km 6,000 km Inner Core General Science IA Credit 2 Depth (km)