Chapter 10, Problem 2FQ

To determine

The largest Earth’s internal zones.

Answer to Problem 2FQ

Mantle is the thickest layer of the Earth while crust is the thinnest layer. The crust is very thin when compared to the mantle. The thickness of crust varies from 5 to 70 kilometers (3-43 mi.), while the thickness of mantle is 2,885 kilometers (1800 mi).

Explanation of Solution

The major zones of the Earth’s interior in order from the center to the surface are inner core, outer core, mantle, oceanic crust, and continental crust. These zones vary by the material composition, thickness and density, which are decreasing toward the surface from the center.

The deepest section of the Earth’s interior is the core. It encompasses one third of the Earth’s mass and having a radius of 3360 kilometers, the core is primarily composed of iron and nickel. The core has two sections, solid inner core and molten outer core.

Mantle is 2885 kilometers thick layer above the outer core and it consists of about two third of the Earth’s mass. Mantle is less dense than the outer core and it is composed of solid rock materials. Mantle has high silicate content and significant amount of iron and magnesium.

Crust is the solid outer layer of the Earth, which consists of vast variety of rock types. When compared to the core and mantle, the density of crust is considerably less. Crust is also thin when compared to the thickness of core and mantle. The thickness of crust ranges from 5 to 70 kilometers. Crust has two sections, oceanic crust and continental crust. In relation to the size of the Earth, the crust is comparable to the relative thickness of an eggshell to an egg.