Exam 4: Up From the Inferno: Magma and Igneous Rocks

All other factors being equal, if a body of magma becomes more felsic, its viscosity will __________ .

The interior of Earth consists almost entirely of __________ rock.

The May 18, 1980, eruption of Mount St. Helens was unique in which way?

Which of the following is not a way in which geologists can monitor a volcano with the goal of making short-term predictions about volcanic activity?

The difference between magma and lava is that __________ .

What is the fundamental difference between an explosive and an effusive eruption? What variables are important in determining whether a volcano "flows" or "blows"?

What are some of the main volcanic hazards?

__________ form from piles of pyroclastic debris (mainly lapilli) that fountain out of a vent during an effusive eruption.

If the volatile content of magma is increased, its viscosity will __________ .

A batholith is a(n) __________ .

Which type of magma has the greatest silica content?

Viscosity of a magma does NOT depend on __________ .

What is a caldera? How is a caldera different from a stratovolcano?

An irregular-shaped and bloblike igneous rock body that cooled beneath the surface of Earth is a __________.

Volatiles are substances that __________ .

Viscosity controls how __________ .

All other factors being equal (i.e., depth, volume, temperature, etc.), which type of igneous intrusion would cool fastest?

Volcanic arcs form along __________ boundaries.

Granite, a course-grained, felsic intrusive igneous rock is most similar in mineral composition to __________ , which is a fine-grained, felsic extrusive equivalent.

The image below (immediately to the right of the person's head) is an example of a small __________ .