Exam 9: Volcanoes and Other Igneous Activity

The ________ ocean basin is rimmed by the most subduction zones.

Matching. Please choose from one of the following answers. -small basaltic cones built during one short, eruptive episode

Volcanoes are generally not preserved in the geologic rock record as they are eroded away. However, the various materials erupted from volcanoes are often found preserved in the rock record. How could you infer what type of volcano erupted in a given area based on the type of volcanic deposits now found as layers of rock? Give specific examples and briefly discuss if some materials may be linked to different types of volcanoes.

Word Analysis. Examine the words and/or phrases for each question below and determine the relationship among the majority of words/phrases. Choose the option which does not fit the pattern.

________ is a dangerous, fast moving, hot, turbulent cloud of volcanic gases and fine-sized, pyroclastic particles.

Magma tends to rise toward Earth's surface principally because ________.

Kilauea and Mauna Loa are ________.

Given the nature of explosive volcanic eruptions here on Earth and the role of dissolved gases (principally water vapor), what might you expect of volcanoes erupting on other planets similar to Earth, such as Mars or Venus? Remember that Venus has a thick atmosphere of carbon dioxide, but water vapor is apparently absent from these planets.

The Columbia Plateau in the northwestern United States is an excellent example of ________.

Basalt is the most common magma erupted along oceanic rift systems.

A very large, discordant pluton, commonly composed of granite is a(n) ________.

Which one of the following statements concerning cinder cones is false?

The viscosities of magmas increase with increasing percentages of silica.

The average composition of rocks comprising a large composite cone or stratovolcano is similar to a(n) ________ magma.

Spreading center volcanism most generally produces rocks that are ________.

Most of the active volcanoes on Earth are located in a belt known as the ________.

Most basaltic magmas are believed to form by partial melting of granite in the lower crust and upper mantle.

What is the name of the chain of volcanoes below that forms at an oceanic to continental plate boundary?

The 1943 eruption of Paricutin in Mexico was characterized by ________.

In 1980, ________ was the first Cascade Range volcano to erupt since Mt. Lassen in 1915-16.