Iceland is one of the few places in the world that is both above sea level and situated atop a ________ plate boundary.

Compared to oceanic crust, continental crust is ________.

The distinction between the crust and the mantle is primarily on the basis of a difference in ________; the distinction between the lithosphere and the asthenosphere is primarily on the basis of a difference in ________.

What will eventually happen to the headlands in the figure below?

How does the formation of oil shale deposits, coals, and limestones effect the carbon dioxide (CO2) concentration in Earth’s atmosphere?

The shape of a delta is primarily determined by ________.

In the figure below, which letters represent the crest and trough?

Cleavage in minerals refers to ________.

In ancient Greece, Eratosthenes measured the difference in angles of the Sun’s rays in two different locations in Egypt at the same time to calculate the ________.

Evidence of paleomagnetism can be found in ________.