Advertisement Upgrade to remove ads

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

Mt. St. Helens

Which type of basaltic lava flow has a fairly smooth, unfragmented, ropy surface?


____ is a major dissolved volatile constituent in both magmas and volcanic gases?


Volcanic bombs originate _____

as erupted magma blobs that partly congeal before falling to the ground

Which natural phenomenon occurs for many years after major explosive volcanic eruptions such as Tambora and Pinatubo?

brilliantly colored sunrises and sunsets

What fate befell the ʹLost City of Atlantisʹ mentioned in Platoʹs writings?

it disappeared as part of caldera collapse following a major, explosive, volcanic eruption

________ magma is the most abundant type of erupted at oceanic spreading centers.


The 1991 Pinatubo eruption in the Philippines caused brilliantly colored sunrises and sunsets to be seen for the next few years. What caused this phenomenon?

sulfur dioxide and other erupted gases formed aerosols in the stratosphere

the ____ ocean basin is rimmed b y the most subduction zones


Which was the most powerful, explosive volcanic eruption of historic time?

Tambora, Indonesia, 1815

Which of the following is associated with deep mantle hot spots?

the volcanoes of Hawaii and Quaternary activity in Yellowstone National Park

Why would a plume of solid silicate rock rising slowly from deep in the mantle begin melting as it neared the base of the lithosphere?

temperatures remain high as lowered pressures decrease melting temperatures

Which of the following best describes seamounts and islands of the deep ocean basins?

piles of basaltic lava flows built up from the ocean floor by multiple, summit and flank

Pockets of magmas can be formed by the melting of deep continental crust heated by the intrusion of other magmas. Which of the following correctly describes this process?

intrusion of basaltic magma causes deep crustal rocks to melt, producing andesitic or rhyolitic magmas

Which of the following phenomena accompanied the year without a summer (1816) in parts of North America and northern Europe?

snow falls and frosts in New England during July and August

________ are usually the most abundant gases emitted during basaltic volcanism.

Water and carbon dioxide

massive, gently sloping volcanoes built of successive, basaltic lava flows

shield volcanoes

large, fairly steep-sided cones composed of lavas and pyroclastic layers


small basaltic cones built during one, short, eruptive episode

cinder cones

the volcanoes of southwestern Alaska and the Aleutian Islands


the big volcanoes of Hawaii

shield volcanoes

Which statement about the May, 1980, eruption of Mount St. Helens is false?

during the eruptive period, the mountain peak was substantially built up by new lava flows
and pyroclastic debris

________ tend to increase the explosive potential of a magma body beneath a volcano.

High viscosity and dissolved gas

Which type of basaltic lava flow has its surface covered with sharp-edged, angular blocks and rubble?


Which one of the following statements concerning volcanic blocks and bombs is true?

bombs are ejected as magma lumps; blocks are ejected as solid fragments

______ destroyed the city of St. Pierre, Martinique in 1902

a Nuee ardente

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

the cinders and other pyroclastic particles are consolidated into welded tuff

The Columbia Plateau in Washington and Oregon is ________.

a flood basalt plateau

Which kind of eruptive activity is most likely to be highly explosive?

eruptions of big, continental margin, composite cones or stratovolcanoes

Which one of the following statements is not true?

when magma reaches the surface, its dissolved gas content increases

Which kind of volcanism is typical of mid-oceanic ridge systems?

submarine; basaltic lava flows

Kilauea and Mauna Loa are _____.

basaltic shield volcanoes

Mt. St. Helens is ____

an explosive stratovolcano

the 1943 eruption of Paricutin in Mexico was characterized by ____.

cinder cone building and basaltic lava

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


A ________ volcano is a very large, gently sloping mound composed mainly of basaltic lava flows.


Which of the following best describes Shiprock, a famous volcanic feature in New Mexico?

the eroded remains of a volcanic pipe and radiating dikes

Which region has the greatest concentration of currently active volcanoes?

the circum-pacific area

The recent (geologically) volcanic activity in Yellowstone National Park is ________.

related to intraplate, hot spot volcanoes

The icelandic volcanoes are related to plate tectonics because ______.

they lie on a spreading center where two plates are moving apart

Which one of the following best describes volcanism in the Cascade Range, northwestern U. S.?

related to plate subduction

Which of the following statements best describes the big Hawaiian volcanoes?

are situated in the interior of a large, Pacific plate above a hot spot deep in the mantle

At low pressures and in the absence of water, rhyolites and granites begin to melt at about ________.

800 degrees C

What volcanic events formed Crater Lake, OR? When did they take place?

caldera collapse followed major ash and pyroclastic-flow eruptions; 6000 years ago

Which one of the following shows the correct order (left to right) of decreasing magma viscosity?

rhyolite, andesite, basalt

Why do magmas rise toward earth's surface?

magmas are mainly liquid and contain dissolved fluids such as water; most are less dense than the adjacent solid rock

What is the largest, known volcano in the Solar System?

Olympus Mons, Mars

A ____ is the largest, discordant body of intrusive, igneous rock.


A ____ is an intrusive, igneous rock body that is tabular and concordant.


A ___ is a near surface, intrusive, igneous rock body that results from local inflation of a horizontal sill?


Which of the following best describes the bedrock in the Sierra Nevada Mountains in California?

granite; batholiths

Xenoliths are associated most closely with which magmatic process and igneous rock body?

intrustion; granitic batholith

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording