Ch 6 Quiz

What are some factors that could allow flood basalts to have high-volume eruptions?

A large amount of magma is generated in the mantle. Magma rises to the surface along thick dikes. The magma is hot and has a low viscosity.

Which of the following are differences between an eruption column and pyroclastic flow?

A pyroclastic flow forms when the gas flux cannot support the column.

Which of the following types of volcanic eruption have occurred on Mount St. Helens since it began erupting in 1980?

Eruption column, pyroclastic flow, and volcanic dome

This relatively small volcanic feature consists of solidified lava and some volcanic ash. What kind of volcano is it?

NONE (scoria, shield, composite, caldera)

Which of the following are erupted by volcanoes?

Pumice, ash, lava

This volcano is broad and low, and is composed of basaltic lava flows. What kind of volcano is it?

Shield

The most common volcanic rock found in lava flows on composite volcanoes is

andesite.

Composite volcanoes are so called because they

are composed of lava flows, pyroclastic material, and mudflows.

Hazards associated with basaltic lava flows and eruptions are

burial of roads and neighborhoods by lava flows., house fires, and floods from catastrophic melting of ice.

Which of the following commonly precede a volcanic eruption?

increased gas flow from a volcano, steam eruptions from the volcanic crater, increased heat flow from the volcano

Which of the following is NOT a typical match between the type of eruption and resulting rock type?

pyroclastic flow-scoria

Which of the following lists the four types of volcanoes shaped like hills and mountains?

scoria cone, shield, composite, dome

What are the rounded hills inside the Valles Caldera?

volcanic domes