Question

The Earth's outermost layer is the crust. However, not all crust is the same. Oceanic crust differs from continental crust in many ways. Consider the information provided, and highlight the sentence that explains why oceanic crust is younger than continental crust.

Answer 1

Oceanic crust is younger than continental crust because it is constantly being created and recycled through volcanic activity, while continental crust is composed of much older rocks.

Step-by-step explanation:

One sentence that explains why oceanic crust is younger than continental crust is because oceanic crust is constantly being created at mid-ocean ridges through volcanic activity, while continental crust is composed of much older rocks.

For example, the process of seafloor spreading at mid-ocean ridges creates new volcanic rocks that form the oceanic crust. These rocks are relatively young, usually less than 200 million years old. On the other hand, continental crust is made up of older rocks that have been reworked and altered over billions of years.

This is due to the fact that the oceanic crust is constantly being recycled through subduction zones, where it sinks back into the mantle and is eventually melted and remade at mid-ocean ridges again. In contrast, continental crust is not being destroyed in the same way and can persist for billions of years.