PHYS 0103/0104: Physical Geology
Fall Semester, 2004
Final Exam
Name: ______________________________
Part I: Mu lt ip le Cho ice /Fill-I n. Choose the be s t answer for each multiple choice question
and circle the corresponding letter. You should circle only one letter for each question. If you
change your mind, be sure to indicate clearly your final choice - no credit will be given for
ambiguously marked questions. Follow other directions within the questions as appropriate.
Each question is worth 2 points.
1.
Valley glaciers often originate in bowl-shaped hollows high in the mountains. These
hollows, which often contain lakes after the glacier has vanished, are called
a) cirques
b) sinkholes
c) cut banks
d) moraines
2.
According to the Principle of Superposition: In a sequence of ----- rocks, the oldest rock
layer is on the bottom, the youngest on the top.
a) igneous
b) sedimentary
c) metamorphic
d) WHOAA!! - that's true of all the different kinds of rocks
3.
Rocks metamorphosed during the collisions that formed Pangaea and erosional features
produced by the glaciers of the last ice age are prominent features of
a) Yosemite National Park
b) Acadia National Park
c) Yellowstone National Park
d) Canyonlands National Park
4.
According to Hess' idea of sea-floor spreading, new sea floor is constantly being produced
by volcanic activity along the
a) mid-ocean ridges
b) coastlines of the continents rimming the Pacific
c) deep ocean trenches
d) San Andreas fault
5.
Tsunamis are generated as a result of
a) earthquakes on the sea floor
b) volcanic eruptions that send material into the sea
c) rockslides into the sea
d) WHOAA!! - any of those causes might generate a tsunami!
6.
The breaking down of bedrock (or large boulders) into smaller pieces of the same mineral
composition, for example by frost wedging, constitutes
a) lithification
b) mechanical weathering
c) mass wasting
d) chemical weathering
PHYS 0103/0104: Physical Geology
Final Exam
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7.
The geological structure shown in the cross-section at the
right is a(an)
a) normal fault
b) anticline
c) reverse fault
d) syncline
8.
More than 100,000 people in the ----- area live on deposits of old lahars, and are at risk of
being buried by future lahars.
a) Sacramento
b) Seattle-Tacoma
c) Mexico City
d) Anchorage
9.
To get permission to install a septic tank, landowners must have a "perc test" completed.
This involves digging a hole in the ground, filling it with water, and waiting to see how
long it takes the water to drain into the ground. This "test" is checking the
a) porosity of the surface materials in the area
b) depth of the groundwater table in the area
c) permeability of the surface materials in the area
d) slope of the groundwater table in the area
10.
The cross-section at the right shows a lake in a humid region,
like Massachusetts. Sketch in the approximate position of the
groundwater table in this area.
11.
Yosemite Valley is a classic example of a(an)
a) glacially eroded U-shaped valley
b) V-shaped river valley
c) graben, a valley bounded by normal faults
d) solutional valley, created by acidified ground water
12.
The greenhouse effect
a) operates when gases in the atmosphere trap infrared light
b) may explain why the Earth's surface appears to be warming
c) could be strengthened by the release of CO2 from burning fossil fuels
d) all of the above
13.
Regionally metamorphosed rocks often display
a) glassy texture
b) foliation
c) detrital texture
d) bedding
14.
Much of the damage that took place during and after the Loma Prieta earthquake of 1989
was the result of
a) a tsunami
b) lahars
c) liquefaction
d) flooding
PHYS 0103/0104: Physical Geology
Final Exam
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15.
The most common kinds of cave decorations, including stalactites and stalagmites, are
generally composed of
a) carbonate minerals, like calcite
b) silicate minerals, like quartz
c) sulfate minerals, like gypsum
d) salts, like halite
16.
When a geologist scratches a mineral sample on a glass plate, she is testing the ----- of the
mineral.
a) streak
b) density
c) hardness
d) cleavage
17.
Oil and natural gas are often found "trapped" in sedimentary rock layers. The most
important attribute of a good "cap rock" (which seals the "trap") is that it should
a) have a mafic composition
b) have a low permeability
c) contain large amounts of quartz
d) be very poorly sorted
18.
The basalt unit shown in the cross-section at the right would
be called a(an)
a) dike
b) xenolith
c) varve
d) cross-bed
19.
Springtime floods that result from excessive rainfall and melting of snow are called
a) flash floods
b) storm-surge floods
c) regional floods
d) ice-jam floods
20.
Igneous rocks form by ----- .
a) cooling and crystallization of molten rock
b) chemical or biochemical precipitation of minerals
c) alteration of earlier rocks due to high temperatures and/or pressures
d) lithification of loose material
21.
The bedrock through which the Colorado and Green Rivers have cut the canyons of
Canyonlands National Park consists primarily of
a) ancient schists and gneisses formed by regional metamorphism
b) horizontally layered sediments of both marine and terrestrial origin
c) granitic batholiths formed as a result of subduction of the Pacific ocean floor
d) thick sequences of limestones, deposited in shallow tropical seas
22.
A lake that forms within a depression created by the melting of a block of glacial ice (previously
surrounded by sediments) is called a (an)
a) arete
b) drumlin
c) kettle
d) esker
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Final Exam
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23.
Clouds of hot ash and rock fragments, known as -----, sometimes sweep downhill at speeds
of up to 150 km/hr following a volcanic eruption.
a) lahars
b) debris flows
c) pyroclastic flows
d) tsunamis
24.
An earthquake with a Richter magnitude of 8 would produce about ----- times as much ground
shaking as a quake with a Richter magnitude of 5.
a) 3
b) 50
c) 1,000
d) WHOAA!! - the magnitude has nothing to do with the amount of ground shaking!
25.
In science, a "theory" is
a) a wild idea that has never really been tested, but could be right
b) a possible explanation for something, but not very likely to be useful
c) a well-tested explanation, that appears to be very useful
d) an explanation that has been proven to be absolutely correct
Part II: True /Fa lse: Indicate whether each statement is true (T) or false (F) by putting the
appropriate letter on the blank by the question number. I f the statement is false, then cross
out the incorrect portion and replace it with a correct word or phrase in the space below,
including specific information that shows how the original statement was false. Information in
parentheses is provided for clarification and will not need to be corrected. Each question is
worth 2 points.
_____1. You can often identify a rock as "igneous" because it is made of mineral crystals that
are arranged into a distinctive pattern.
_____2. Geologists believe that the past couple million years have been marked by a series of
oscillations between ice age conditions and warmer periods.
_____3. Three enormous volcanic eruptions during the past 2 million years created the central
caldera that is at the heart of Mount Rainier National Park.
_____4. Geologists have figured out the internal structure of the Earth primarily by using
seismic waves as probes of the interior.
_____5. The root systems of trees and other types of vegetation generally help to stabilize
surface materials against mass movements.
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Final Exam
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Part II I. Shor t Ans w er: Answer a ny four of the following five questions. Two to four
sentences should be sufficient, but be sure to give a complete answer. Each question is worth 5
points.
1.
Give a geographical example of a place on Earth where a convergent plate boundary exists.
What relative motion of the plates would be occurring there, and what geological features
would likely be present? Explain briefly.
2.
The diagram below shows a portion of a topographic map with a contour interval of 10
feet. The thin line that cuts across the contour lines is a stream. What is the approximate
elevation of the land surface at the point marked by the "x"? Is the stream flowing north
or south through this area? How did you know?
3.
Caves are almost always found in regions of limestone (occasionally marble) bedrock.
Why do suppose that this is true, and what other factors do you think might tend to
promote the formation of caves? Explain briefly.
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Final Exam
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4.
The two seismograms below show the records of two different earthquakes, both recorded
in Westfield. Identify the P-wave and S-wave arrivals on each seismogram. Which quake's
epicenter was closer to Westfield? Explain. What can you say about the relative
magnitudes of the two quakes?
5.
New Hampshire is known as the "granite state" because granitic bedrock is exposed over
large portions of the state. What two geological events must have taken place in order for
large bodies of granite to be exposed at the Earth's surface? Explain.
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Final Exam
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Part I V. Es say s: Answer e it her of the following questions. Use complete sentences and
compose your responses carefully - the marks are based on clarity of expression as well as
content. Two or three good paragraphs should suffice, but be sure to give a complete answer.
This question is worth 20 points.
1.
The hydrologic cycle is responsible for the "circulation" of water near the Earth's surface.
Briefly describe that cycle, being sure to mention the major reservoirs for water and the
major processes that transfer water between reservoirs. Which aspect of the hydrologic
cycle has likely been most important in shaping the landscape of New England? Explain
briefly and support your choice by describing the nature and origin of two New England
landforms that are related to that part of the cycle.
2.
The cross-section below shows the bedrock in a particular area, with units identified in the
key to the right (where the rocks are shown in alphabetical order). Interpret the
geological history of this area: begin by determining the order in which the rock units
formed (note the inclusion of gneiss within the conglomerate!), then go on to describe the
events that must've taken place to produce this sequence. Try to relate those events to
larger scale (e.g. tectonic) processes where possible.