Geol chap 6
Which of the numbered features is a pyroclastic column
3
Which of the following sites would most likely have composite volcanoes? A is on in Island Arc, B. is in the Andes, See if near Hawaii, D is along a mid ocean ridge
A and B
Which of the following is a hazard but not a risk, according to the textbook?
A scoria cone that erupts hot molten fragments on an unpopulated Pacific island
Which of the following sites near a volcano might be relatively less dangerous?
A site on a ridge as opposed to a site in a valley.
The largest volcanic Irruption's on earth are flood of
Basalt magma
This relatively large, symmetrical volcano contains interlayered lava flow, pyroclastic deposits, and volcanic my phone. What kind of volcano is this?
Composite volcano
The typical shape of most volcanoes, including the one shown here is
Conical
What type of irruption is shown in this photograph
Lava dome
Which of the following is NOT a reason why heat flow and gas output from a volcano tend to increase before eruptions?
Melting of snow caps dissolves large amounts of water into the magma.
This volcano is brought in low, and is composed of basaltic lava flow. what kind of volcano is this?m
Shield volcano
Shield volcanoes have low slopes primarily because
The low viscosity of basaltic magna allows it to flie down hill for long distances
Which of the following occurs in a lava tube?
The surface of the lava flow solidifies to form a roof over the moving lava . Lava tubes insulate a lava flow, allowing it to flow farther. If a lava tube drains, it becomes a tube-shaped cave. All of these cholces are correct
Which of the following is NOT true about shield volcanoes in the landscape?
They are large mountains with steep slopes.
Which of the following are ways that viscosity affects gases in magma?
Viscous magma prevents gas from escaping easily.
The eruption that occurred on Mount St. Helens was triggered by
a huge landslide, caused a lateral blast that knocked down trees and buildings.
Which of the following is common in most calderas?
a large, circular depression with steep walls thick sequences of volcanic ash rounded mountains that are volcanic domes All of these choices are correct.
Which of the following is common in most calderas?
a large, circular depression with steep walls thick sequences of volcanic ash rounded mountains that are volcanic domes All of these cholces are correct.
Which of the following factors indicates a high risk for volcanic mudflows or lahars?
a volcano with a thick covering of snow or ice
The most common volcanic rock found in lava flows on composite volcanoes is
andesite.
If bubbles cannot escape easily from a magma, the resulting eruption is likely to
be explosive.
The most dangerous type of volcano is a
composite volcano.
What type of volcano is Mount Rainer
composite volcano.....
What types of rocks would be most common in a composite volcano?
felsic and intermediate lava flows and tephra
Flood basalts influence life on Earth because
large volumes of flood basalts are erupted during a short time. eruptions can release large amounts of gas that cool the atmosphere. eruptions can release large amounts of gas that warm the atmosphere. All of these choices are correct.
Volcanic eruptions produce huge floods by
melting ice sheets.
What tectonic setting is interpreted to be the cause of volcanism at Yellowstone?
movement of North America over a mantle plume
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 materials is NOT produced by erupting volcanoes?
sandstone
The volcano is relatively small and composed of volcanic cinders. What kind of volcano is it?
scoria cone
Which of the following volcanoes is generally the largest?
shieid volcano
Which of the following volcanoes is generally the largest?
shield volcano
Which of the following are characteristics typical of volcanic domes?
steep-sided rubble-covered surface often occur in clusters All of these choices are correct
