Exam 5: Volcanoes and Volcanism

A lahar may form when ____.

____ in California is the world's largest lava dome.

The one place on Earth where mid-ocean ridge volcanism occurs above sea level is ____________________.

After a volcano erupts, the frequency of its future eruptions follow a very predictable pattern.

The Hawaiian islands formed via ____ volcanism.

Harmonic tremor indicates that magma is moving beneath a volcano.

Most scientists believe that volcanism has played a major role in the depletion of the ozone layer in Earth's stratosphere.

Why are there volcanoes on the west coast of North America but not on the east coast?

Not all volcanism results in the origin of volcanoes.

A dense cloud of pyroclastic materials and a glowing cloud of gases and dust is called a(n)____.

Most of the approximately 3,300 historic eruptions lasted ____.

Erupting volcanoes eject pyroclastic materials of varying diameters. These materials, from smallest to largest are ____________________, ____________________, ____________________, and ____________________.

Composite volcanoes are also known as ____________________ and are composed of both lava flows and ____________________ material.

Columnar jointing in lava flows occurs due to ____.

Fissure eruptions result in shield volcanoes.

The relatively small eruptions of the Icelandic volcano Eyjafjallajokull in 2010 caused major disruptions because the eruptions ____.

Some lava flows show a pattern of columns bounded by fractures. These columns are usually ____-sided.

An extinct volcano ____.

Nearly all remaining active volcanoes ____.

Pillow lava forms when ____.