Crust

The Earth's crust is the outermost layer of the Earth. It is a solid, thin layer that covers the Earth's surface and is made up of various types of rocks and minerals. The crust is divided into two types: continental crust and oceanic crust.

Continental Crust

Continental crust is the thicker of the two types of crust and primarily consists of granite rocks. It is less dense than oceanic crust and is generally older. Continental crust forms the continents and the areas of shallow seabed close to their shores, known as continental shelves. It is typically 30-50 kilometers thick but can be up to 70 kilometers thick in mountainous regions.

Oceanic Crust

Oceanic crust is the thinner and denser of the two types of crust and is primarily composed of basalt rocks. It is younger than continental crust and is constantly being created at mid-ocean ridges and destroyed at subduction zones. Oceanic crust is relatively uniform in thickness, typically about 5-10 kilometers thick.

Study Guide

1. What is the Earth's crust?
2. What are the two types of crust?
3. Describe continental crust.
4. Describe oceanic crust.
5. What are the primary differences between continental and oceanic crust?
6. Where is new oceanic crust formed?
7. Where is oceanic crust destroyed?
8. How does the thickness of continental crust compare to oceanic crust?

[Crust] Related Worksheets and Study Guides:

• Earth's CrustEarth Science • High School
• Plate tectonicsScience • Eighth Grade
• Our EarthScience • Kindergarten