CK-12 Foundation
Ck 12: Earth Science: Earth's Mantle
The composition and behavior of the Earth's mantle. [Free Registration/Login may be required to access all resource tools.]
CK-12 Foundation
Ck 12: Earth Science: Principle of Uniformitarianism
How to use information from the present to understand the past.[Free Registration/Login may be required to access all resource tools.]
CK-12 Foundation
Ck 12: Earth Science: Tectonic Plate Motions
Earth's tectonic plates and how they move. [Free Registration/Login may be required to access all resource tools.]