Exam 5: Volcanoes and Volcanism

A volcano is considered extinct if it has not erupted for more than 1,000 years.

Columnar joints caused by the contraction of lava as it cools form typically in a(n)____________________ shape.

Cinder cones rarely reach heights greater than ____________________;they are composed of ____________________ material of ____________________ composition.

A volcanic tremor indicates that magma is moving beneath the surface and an eruption is likely to be soon.

Would you rather be chased by a pahoehoe flow or an aa flow? Explain.

An ash fall occurs when volcanic ash is ejected into the atmosphere and settles to the surface.

Volcanic activity that takes place away from plate boundaries is the result of volcanism at a(n)____________________.In the U.S. ,an example of this type of volcanism in the ocean is ____________________;an example on land is ____________________.

Pyroclastic materials include:

The volcanic explosivity index (VEI)can be correlated with the number of deaths caused by an eruption.