Geol 171 Exam 2

Front 1

The largest explosive volcanic eruption in the last 500 years occurred at ___________.

Back 1

Tambora, Indonesia

Front 2

A resurgent dome develops

Back 2

as new magma enters the remains of an old chamber beneath a collapsed caldera.

Front 3

A return of the major New Madrid earthquakes would

Back 3

probably reach Modified Mercalli Intensity VI or VII in Kansas City.

Front 4

Rock can be caused to melt by

Back 4

a) decreasing the pressure on it.
b) raising its temperature.
c) increasing its water content.
d) all of these
e) none of these

Front 5

Spreading-ridge magma has _________________ relative to subduction-zone magma.

Back 5

high temperature and low viscosity

Front 6

Increasing the water pressure between sand grains,

Back 6

can cause liquefaction.

Front 7

If Vesuvius erupted with a vengeance similar to that of the 79 C.E. eruption, which of the following cities
would be at greatest risk?

Back 7

Naples

Front 8

The most dangerous volcanoes are mostly

Back 8

in subduction zones

Front 9

Active volcanoes today in Washington and Oregon are caused by

Back 9

the subduction of the Juan de Fuca plate beneath the North American plate.

Front 10

The Hayward Fault passes through the middle of the _______________

Back 10

University of California Berkeley football stadium

Front 11

The Earth’s crust in the eastern United States is __________ and the crust in the western United States is
________ .

Back 11

under tectonic compressional stress ; under tectonic tensional stress

Front 12

Relatively viscous basaltic lava that solidifies with a blocky texture is called __________.

Back 12

aa

Front 13

The last magnitude 9 earthquake in the 48 contiguous U. S. states occurred in 1700 in

Back 13

Washington

Front 14

Assume a Richter magnitude 6.0 earthquake in Missouri on the same day that a magnitude 6.0 occurred in
San Francisco, California. The shaken area would be

Back 14

smaller in California than in Missouri.

Front 15

Which of the following states has the lowest earthquake risk?

Back 15

Minnesota

Front 16

In the United States, which of the following calderas had a major eruption about 600,000 years ago?

Back 16

Yellowstone caldera, Wyoming

Front 17

A genuine success story of advance warning before a large eruption occurred in the Philippines in 1991
before the climactic eruption of .

Back 17

Mount Pinatubo

Front 18

In 1883, a tsunami caused by the eruption of this volcano killed 36,000 people; the volcano was

Back 18

Krakatau, Indonesia.

Front 19

Spectators at the eruption of which type of magma are least likely to die?

Back 19

basalt

Front 20

The eruption of ______________ caused “the year without summer” in New England.

Back 20

Tambora in 1815 C.E.

Front 21

The Pacific Rim is home to about 70–75% of the world’s earthquakes. The percentage of the Earth’s
active volcanoes located around the Pacific Rim is

Back 21

about the same as this.

Front 22

Santorini erupted explosively in about 1628 B.C.E. and buried the city of .

Back 22

Akrotiri

Front 23

If the lava reaches the sea or a lake, it cools rapidly into ______________.

Back 23

pillow lava

Front 24

A pyroclastic flow is a flow of

Back 24

hot particulate material down the side of a mountain.

Front 25

Hot spot volcanoes

Back 25

in the ocean are less dangerous than those on the continents.

Front 26

The number-one volcano on the danger list of many U.S. volcanologists is .

Back 26

Mt. Rainier, Washington

Front 27

Which of the following produces the "rotten egg smell" around volcanoes and some hot springs?

Back 27

hydrogen sulfide (H2S)

Front 28

The SO2 released into the atmosphere by the Mt. Pinatubo eruption in 1991

Back 28

caused short-term (a few years of) global cooling.

Front 29

The dominant volcanic gas (commonly 90% or more of total gas) is

Back 29

water vapor (H2O)

Front 30

Which of the following crystallizes underground and has relatively low silica content?

Back 30

gabbro

Front 31

Volcanoes at Yellowstone, in Wyoming, and in Hawaii are most closely related to

Back 31

hotspots

Front 32

Which of the following building scenarios would be most resistant to damage from seismic shaking
during the 1989 Loma Prieta earthquake?

Back 32

1-story brick building built on solid rock

Front 33

The San Andreas Fault is ___________________ .

Back 33

primarily a right-lateral transform fault

Front 34

In Cameroon, Africa, in 1986, a volcanic lake burped and sent a flood of carbon dioxide over the rim of
the crater, killing ___________ in its path.

Back 34

most of the animals and including 1700 people

Front 35

Techniques used to predict the volcanic eruption at Pinatubo included which of the following:

Back 35

monitoring the amount of emission of sulfur dioxide
b) monitoring local earthquake activity beneath the volcano

Front 36

On March 1, 2007, a tornado ripped through a high school in the town of Enterprise, killing 8 students.
This occurred in

Back 36

Alabama

Front 37

How many great earthquakes (magnitude greater than 8.0) have occurred in the Pacific Northwest (i.e.,
Oregon and Washington) in the past 200 years?

Back 37

None

Front 38

Which direction is the Juan de Fuca plate moving with respect to the North American plate?

Back 38

E

Front 39

During an earthquake, sediment can become water-saturated and get reworked to take up less volume,
which causes the material to behave like a liquid. This process is called ______.

Back 39

liquefaction

Front 40

Which of the following was the most expensive earthquake in history in terms of damage?

Back 40

Kobe, Japan, 1995

Front 41

Three of the four largest earthquakes that have occurred since 1800 in the contiguous United States
occurred where?

Back 41

New Madrid, MO

Front 42

To minimize loss of life, the best time to have an earthquake is ________.

Back 42

nighttime

Front 43

Flat areas along strike-slip faults that are filled in naturally with sediments are called __________.

Back 43

sag ponds

Front 44

The largest recorded earthquakes occur in _________ where two plates move ________ with respect to
one another.

Back 44

subduction zones, together

Front 45

Tsunamis can result from

Back 45

All of the above

Front 46

Determining the earthquake and eruption history of an area over the past several thousand years can be
done using

Back 46

Carbon 14

Front 47

“Big one” earthquakes in California occurred in

Back 47

1857 and 1906.

Front 48

The current state of earthquake prediction is that

Back 48

no reliable prediction method exists.

Front 49

Earthquakes can be caused by humans by

Back 49

injecting water under high pressure into faults.
b) setting off nuclear explosions.

Front 50

When a tsunami approaches shore where water gets shallower, it

Back 50

slows down.

Front 51

Hawaii has

Back 51

both active volcanoes and occasional quakes above Richter magnitude 6.0.

Front 52

The time required for a tsunami to cross the Pacific Ocean is

Back 52

several hours

Front 53

The most active of the Cascade volcanoes over the past 4000 years has been .

Back 53

Mt. St. Helens

Front 54

California is famous for earthquakes, but the last volcanic eruption in California was

Back 54

in 1914–1917.

Front 55

The top of Mt. St. Helens now contains

Back 55

a crater with a lava dome inside the crater

Front 56

Volcanism is controlled by the three V’s, which are:

Back 56

viscosity, volume, and volatiles.

Front 57

Which type of lava has the most volatiles?

Back 57

rhyolite

Front 58

The temperature of magma is roughly

Back 58

1,000 degrees C