Chapter 26, Problem 8TE

Solution

To determine: The reason that the crust floats on the mantle.

Answer:

The reason that the crust floats on the mantle because the lower mantle asthenosphere allows it.

Explanation:

The second layer of Earth that is the mantle is further divided into two parts, the first one is the lower mantle or asthenosphere, which has a very high temperature, and it exists in the liquid state.

The second division of the mantle is the upper layer, which is the lithosphere that includes crust lies over the asthenosphere, which has a comparatively lower temperature than the upper mantle so, it exists in solid-state. This allows crust float over the mantle.

Conclusion:

Therefore, the reason that the crust floats on the mantle because the lower mantle asthenosphere allows it.