Geology 101 Final
A 100 year flood occurred last year. What is the probability that a 100 year flood will occur this year?
1%
How much of the Earths water is in aquifers (groundwater)?
1%
What is the probability of experiencing a 100 years flood this year?
1%
What is the probability that a 100 year flood will occur along the Yazoo River in the following year?
1%
Which defines brackish water?
1,000-20,000 mg/l
What is the range of the Modified Mercali Scale?
1-12
What is the range of values in the Modified Mercali Scale?
1-12
Wave action can be felt under water to a maximum depth of approximately
1/2 the wavelength of the wave
On the Richter Scale, how much bigger is a magnitude 7 earthquake, than a magnitude 5 earthquake
100 times
On the Richter scale, how much more intense is a magnitude 7 earthquake than a magnitude 5 earthquake?
100 times
The intensity of an earthquake is reported as a 5 on the Richter Scale. How much more intense is a magnitude 7 earthquake?
100 times more intense
On the Richter Scale, how much smaller is a magnitude 5 earthquake, than a magnitude 7
100 times smaller
On the Richter scale, a magnitude 7 earthquake is ______ times larger than a magnitude 4 earthquake
1000
A piece of wood from an ancient dwelling is removed and dated using ^14C. The wood is found to contain 25% of ^14C it originally started with. If the half life of ^14C is approximately 6000 years, how old is the wood?
1200 years
The distance between the top of two waves is 30 feet. What is the maximum depth that wave action could be felt?
15 feet
You dig a hole 3 feet deep in your backyard. The bottom foot of the hole fills with water. Where is the water table in your backyard?
2 feet bellow the surface
A flood occurs with an average frequency of once every 50 years. What is the probability that a 50 year flood will occur next year?
2%
A calcite sample starts off 10,000 ^14C atoms. After two half lives, approximately how many are left?
2,500
The distance between the crest of waves is 50 feet. How deep in the water can wave action be felt?
25 feet
After two half lives, how much of a radioactive material is left? (assume we started with 100%)
25%
The half life of tritium is 12 years. After 24 years, how much of the original tritium is left in a sample.
25%
^14C has a half life of 5,730 years. How much of the original ^14C is left in a bone after 11,460 years?
25%
If we start with 100,000 ^14C atoms and allow 2 half lives to pass, approximately how many ^14C atoms are left?
25,000
A calcite sample originally contained 1000 ^14C atoms. How many will be left after two half lives
250
If i start with 1000 ^3H atoms, 500 are left after one half life. After a second half life passes, how many ^3H atoms will be left?
250
If we start with 1000 atoms of ^14C, about how many will be left after two half lives have past?
250
If we start with 1000 atoms of ^238U, how many will be left after two half lives?
250
The largest sand dunes on earth are approximately _____ high
250 m
How many seismic stations are needed to determine the location of an earthquake?
3
How many seismic stations are needed to determine the origin of an earthquake?
3
The smallest earthquakes that are still felt by people have a Richter Scale magnitude of about?
3
What is the minimum number of seismic stations needed to determine the location of the epicenter of an earthquake?
3
What is the minimum number of seismic stations required to determine where an earthquake originated?
3
Approximately how much of the Earths water is trapped in the ice caps and glaciers?
3%
How much water on earth is tied up in ice (glaciers and polar ice caps)?
3%
What is the typical geothermal gradient in the earths crust?
30 degrees C per km
What is the probability that a 25 year flood will occur this year?
4%
What is the probability that a 25 years flood will occur this year?
4%
Based on radiometric dating techniques, how old is the Earth?
4.5 Billion years
Approximately how old do geologists think the world is?
4.5 billion years
Geologists claim the earth is approximately how many years old?
4.5 billion years
Water 100 m off the beach is 20 m deep. How far apart must the wave crests be before wave action will be felt on the bottom here?
40 m
An earthquake measures 6 on the Modified Mercali scale at the epicenter. What value would you expect to see at a town 50 miles away from the epicenter?
5
A 20 year flood occurred in Nowhere, Montana in 1976. No floods have occurred there since 1976. What is the probability that a 20 year flood will occur this year in 1996?
5%
What is the probability of having a 20 year flood this year?
5%
The distance between the crest of each wave is about 10 feet. The height of each wave is about two feet. To what depth will wave action felt?
5ft
An earthquake measures 3 on the Richter Scale. One year later, an earthquake 1000 times more energetic occurs. What will the new earthquake measure on the Richter scale?
6
Which value is NOT possible on the Modified Mercali Scale?
7.5
Approximately how much of the earths water is contained in the ocean?
96%
How much of the earths water is in the oceans?
>95%
The roof of a cave is most likely to collapse under which circumstance? (Ignore weathering and erosion)
A cave that was filled with water becomes dry after a drought
Which is turbidity current?
A dense flow of sediment and water along a sloping bottom of a lake or ocean
Which statement is true?
A glacier can have many end moraines, but only one terminal moraines.
Which is an example of quick clay?
A stable sediment that liquifies under stress
What is an effluent stream?
A stream that gains water from the groundwater
What is an incised stream?
A stream that has cut deeply into the underlying strata
Which is most likely to trigger a mass wasting event?
Adding water to the top of a slope
Which type of alteration produces a metamorphic mineral?
All of the above - rearrangement of existing atoms into a new crystal structure - substitution of one atom for another in a mineral - recrystallization where small minerals grow larger
Ablation from a glacier can happen from
All of the above: - sublimation - melting - calving
Which could produce a tsunami
All of the above: - underwater landslide caused by seismic shaking - normal fault slippage underwater - reverse fault slippage underwater
Which rock could turn into a gneiss? (give the best answer)
All of the following - shale - granite - schist
What can cause a "50 year flood" to occur more frequently than expected?
All of the following: - increase size of surrounding city - straighten stream channel - dredge stream bottom
Which is an example of ablation from a glacier?
All of the following: - sublimation - calving - melting
Which process contributes to the ablation of a glacier?
All of these - calving - sublimation - melting
In what part of the world is solifluction most likely to occur?
Arctic circle
How can a sedimentary rock end up a mile below the surface?
As sediments are deposited in a basin, the added weight causes subsidence
Which is NOT considered to be metamorphism?
Change in chemical formula of a crystal as it reacts inside a cooling magma chamber
Fresh water sits on top of salt water in an aquifer. A well is drilled into the fresh water zone and pumped. How could salt water get into the well?
Cone of depression in fresh water allows salt water to move upward
Which statement is true?
Dunes with ripple marks require faster flowing water than dunes without ripple marks
A river is found to run up and through a mountain range. Which statement most likely describes what happened?
Erosion by the river was faster than uplift by the range
How can seismologists tell the difference between a nuclear explosion and an earthquake?
Explosions produce intense but brief seismic energy; earthquake seismicity lasts longer
Carbon-14 can be used to date back any rock containing carbon
False
Earthquakes only originate at plate boundaries
False
Earthquakes that occur in Arkansas, Missouri, and Tennessee occur along a plate boundary
False
If all ice on the earth melted, only the tops of the highest mountains would still be above water.
False
If all the glaciers and polar ice caps melted, more than 50% of the land area currently above sea level would be under water
False
If all the glaciers in the world are melted, only the tallest mountains would be above water
False
If slate forms from shale, the bedding planes in the shale will become the cleavage of the slate
False
If the ice caps and all the glaciers melted, only the tops of the highest mountains would still be above water
False
Levees are common along mountain streams
False
Radiometric techniques may be used on a sandstone to determine the age of a formation
False
S-waves cannot travel through water. Because of this, only P-waves travel beyond the margins of continents. S-waves stop at the ocean.
False
What phenomenon will most likely produce quick clay?
Freshwater flushing of marine clay
Why do waves break near the shore?
Friction with the bottom slows the front edge of the wave first
Why does floating ice help preserve fish populations in normal climates?
Ice forms an insulating barrier protecting lower water from drops in air temperature
How is the "Seismic Gap" method used to predict some earthquakes?
In some areas, the interval between major earthquakes is consistent
What do mineral isograds refer to?
Isograd means the same thing as metamorphism (synonyms)
Which is NOT a type of earthquake wave?
K
Why are marine clays the most susceptible to becoming quick clays?
Marine clays start with a high salt content
Which features are NOT associated with the convergence of two oceanic plates where one dives over the other?
Mid-ocean ridge
Over time, the position of a waterfall will tend to
Migrate upstream
Which scale refers to the intensity of an earthquake at the place where it is felt?
Modified Mercali
Which system measures the intensity of an earthquake wherever the earthquake is felt?
Modified Mercali Scale
Scales by which earthquakes are measured include the Richter Scale, the Modified Mercali Scale, and the
Moment Magnitude Scale
The Modified Mercali Scale and the Richter Scale are both measures of earthquake intensity. A third scale is described in the textbook that is a more accurate measure of the energy released by an earthquake. This scale is called the?
Moment Magnitude Scale
Which two terms refer to saturated sediments?
Mudflow and Solifluction
Why are earthquakes along the New Madrid fault felt farther away than earthquakes along the San Andres fault?
New Madrid region is surrounded by sediments; San Andres region is surrounded by rock.
A fossil species that only existed for 50,000 years is also found only on the island of madagascar. Would this make a good index fossil?
No
A strike-slip fault runs beneath a large inland lake. A local resident has expressed concern that movement along the fault could create a tsunami. Is this a legitimate concern?
No
The distance between the top of two consecutive waves is 6m. A diver floats underwater at a depth of 4m. Will the diver feel the wave action?
No
Why is the uranium-lead dating method not very useful for determining the age of rocks that are only a few thousand years old?
Not enough lead has formed to be reliably measured
Which phenomenon could result in older rock units on top of younger rock units?
Overturned fold
What type of seismic waves travel the fastest?
P
Which are the fastest traveling seismic waves?
P
What seismic wave travels the fastest?
P wave
How do we know that the earths outer core is liquid?
P waves pass through the earths center, but S waves do not.
Which has earthquake waves listed from fastest to slowest?
P, S, surface
Which type of wave can travel through both solids and liquids?
P-Waves
The name of this course is
Physical Geology
Solifluction is most common in what type of environment?
Polar (Arctic)
Water is a polar molecule. Why is this significant?
Polar solvents can dissolve minerals better than non polar solvents
Which is a compressional seismic wave?
Primary wave
Terraced floodplains are generally an indication of
Regional Uplift
Sand grains will often travel along a river bottom by being intermittently swept up into the flow and then settling back down again. This mode of transport is known as?
Saltation
Which rock would be (most likely) metamorphosed into slate?
Shale
What is required to make dunes more than 30 m high?
Strong winds
Two earthquakes of the same magnitude occur in California and in Arkansas. The earthquake in California occurs in a rock. the earthquake in Arkansas occurs in unconsolidated sediments. Which statement is most likely true?
The Arkansas earthquake will be felt farther away than the California earthquake
A cave that was completely filled with water is partially drained. Which is true?
The cave roof is MORE likely to collapse after draining
Which is correct?
The epicenter is the point on the surface directly above the focus
Why do waves break near the shore?
The front of the wave slows down due to its interaction with the bottom
Groundwater pumping begins removing water from a cave system. At what point will the cave become more prone to collapse?
The moment the water level drops below the cave roof
A river flows up to and through a mountain ridge. Which is true?
The river was present before the ridge was uplifted
A rock is dated using radiometric techniques and is found to be 200 million years old. What event happened 200 million years ago?
The rock solidified from magma
A zircon crystal is removed from a sandstone and determined to be 245 million years old using a uranium-lead dating method. What event occurred 245 million years ago?
The zircon crystal solidified from a magma
A zircon mineral in a sandstone is removed and dated using ^238U and ^206Pb and is found to be 500 million years old. What event happened 500 million years ago?
The zircon mineral solidified from a magma
Why is ^14C not used to date rocks that are millions of years old?
There is not enough ^14 C left to measure
Which would make the best index fossil?
Trilobite species that lived in all oceans, but for a period of only 5 million years
A cave is initially full of water. The roof of the cave will be LESS stable if the water is pumped out.
True
A clay with 50% porosity will generally have a lower permeability than a sand with 35% porosity
True
A flowing well is an artesian well that overflows without being pumped
True
Differential pressures that would break rock near the surface can fold the rock at greater depth because of the high confining pressure
True
If gravel and silt are mixed in with beach sand, the mixture will have a lower porosity than found in the beach sand alone
True
Increasing confining pressure will increase the tendency of a rock to fold rather than break
True
Moist sand has a higher angle of repose than dry sand
True
Seismic waves remain stronger traveling through unconsolidated sediment than when traveling through rock
True
Seismologists can often tell if movement along a fault was strike-slip, normal, or reverse based on seismic waves measured from the earthquake
True
The height of a tsunami as it travels in deep ocean water is small enough that passengers on a ship may not even notice when it passes them
True
The location of an earthquake in China can be determined using seismographs in South America, North America, and Europe
True
The roof of a limestone cave is more stable (less likely to collapse) if the cave is full of water.
True
The same aquifer can be confined in one place and unconfined in another place
True
The velocity of a valley or alpine glacier is fastest at the top towards the center
True
To a geologist, a block of glacial ice is a rock
True
Under pressure, ice can be bent and folded
True
Water is responsible for most of the erosion in a typical desert
True
What event is generally required to create quick clays?
Uplift of marine clay deposits
When using the uranium-lead method of dating, how do we know the rock we are measuring didn't have lead present to start with?
Uranium bearing minerals are selected that exclude lead during formation
in 1963, the side of a slope failed and a massive rock slide plunged into a reservoir sending a wave over the dam that flooded and killed 3,000 people downstream. Where did this occur?
Vaunt, Italy
What triggered the rock slide at the Vaiont Dam in Italy in 1960 that sent a wave of water over the top of the dam?
Water from rains and from the reservoir lubricated contacts between sloping rock layers
Why is a cave filled with water more stable than an empty cave?
Water helps support the cave roof
What will happen if the top of a well is below the potentiometric surface?
Water will rise in the well and overflow out the top
What river features typically migrate upstream?
Waterfalls
Which coastline is NOT adjacent to an active continental margin?
Western Africa
Vegetation generally increases slope stability. When might vegetation decrease stability?
When a large tree adds
The rock fragments making up a conglomerate are stretched into oval shapes under intense pressure, but there is no recrystallization or change in mineral composition. Is this a metamorphic rock?
Yes
Which is the most radioactive?
^3H (half life: 12 years)
The half life of ^3H is 12 years. The half life of ^14C is 5740 years. Which statement is true?
^3H is more radioactive than ^14C
Which would make the best index fossil?
a fish species that existed for 3 million years; found in all the major oceans
What is an LNAPL
a liquid contaminant that will float on water
What is a DNAPL?
a liquid that is more dense than water
A hanging valley is formed from where
a little glacier used to flow into a much bigger glacier
Which is NOT necessary to create a sand dune?
a low spot in the ground
Waves breaking far from shore indicate the presence of
a reef or sand bar off shore
What was the primary cause of damage and fatalities resulting from the mass wasting event at the Vaiont Reservoir in Italy in the early 1960's?
a rock slide into the reservoir sent a giant wave over the top of the dam
Which describes a corundum porphyroblast?
a rock with large corundum crystals resulting from volcanic metamorphism
Which statement is based on the principle of superposition
a shale sitting on top of a sandstone must be younger than the sandstone
A hanging valley is formed when?
a small glacier flows into a larger, deeper glacier
Where is solifluction typically found?
above the arctic circle
The use of radioactive isotopes to determine the age of a rock outcrop is an example of
absolute dating
Sea cliffs and coastal volcanoes are most likely to be found along a(n)
active margin
The western Northern American coastline is an example of a(n)
active margin
Potable water is
agreeable to taste and not dangerous to drink
Potable water is
agreeable to taste and safe to drink
Sediment will often accumulate in a fan shape at the base of mountain canyons. These sediments form a(n)
alluvial fan
The formation of a(n) ____________ can result in a stream channel rising in elevation over time.
alluvial fan
The formation of what geologic feature can result in a stream channel rising higher into the air over time?
alluvial fan
Which is NOT a result of glacial action?
alluvial fan
A formation that supplies water to a well is called
an aquifer
How is an atoll different from a guyot?
an atoll is a guyot with a reef along its outer edge
Cohesion in the text refers to
an attraction between mineral grains in an unconsolidated sediments
Which dry, unconsolidated sediment will have the highest angle of repose?
angular gravel
Which material could maintain the highest angle of repose
angular gravel
The angle of repose will tend to be the highest for a sediment composed of
angular particles
Which dry material can maintain the steepest angle of repose?
angular pebbles
Sedimentary strata is first uplifted, then tilted, and finally eroded. The erosional surface on the tilted strata is referred to as a(n)
angular uncomformity
A stream that cuts through a ridge as the area is uplifted is called a(n)
antecedent stream
A stream that cuts through a ridge or mountain range is called a(n)
antecedent stream
Solifluction is typically found in what type of climate?
arctic
Two cirques that intersect will form a(n)?
arete
Groundwater discharge into a river is called?
base flow
Folded sedimentary layers are found that form a bowl shape. At the lowest point, the limbs slope upward in all directions. This structure is called a(n)?
basin
Wave refraction results in the energy of the waves being dissipated (decreased) in which coastal configuration?
bay
Which will usually make the best aquifer
beach sand
What term refers to bottom sediments transported slowly downstream?
bed load
Sediment at the bottom of a river that slowly moves downstream is called
bedload
A rock that is ductile is more likely to
bend rather than break
If a rock is ductile, it will tend to
bend rather than break
Where is the most likely place to find trapped oil?
beneath an anticline
A groundwater is sampled and found to have a total dissolved solid concentration of 3000 mg/L. The water is considered to be
brackish
A river that splits into multiple channels and then rejoins into a single channel is called a
braided stream
A stream with multiple channels that interconnect is called a
braided stream
What can cause loss of sand from a beach?
building a dam on a river that discharges near the beach
As a mesa erodes, it is most likely to produce a
butte
When a mesa is eroded down to a single, steep-sided, flat-topped mountain, it is called a
butte
Rock is pulverized and altered along a transform fault boundary. This type of metamorphism is best described as
cataclastic metamorphism
According to the text, scientists are looking at new ways of predicting an imminent earthquake. Which may indicate an approaching earthquake?
change in water level in wells
In sequence stratigraphy, sequences of sedimentary deposits are bounded by unconformities. What typically caused the unconformities?
changes in sea level
Convectional rising of air often occurs over large cities because
city temperatures tend to be higher than surrounding areas
Which material has a high porosity but low permeability?
clay
Which description is most likely to cause quick clay?
clay deposited in seawater, followed by an uplift and leaching of salts by freshwater
Where is the fastest flowing water in a stream most likely to be found?
close to the center near the top
Which will have a higher permeability?
coarse sand with 35% porosity
What is the most common cause of fatalities during an earthquake?
collapsed buildings
Folded rock is evidence of what tectonic process?
collision of two plates (convergence)
What is a stack?
column of rock standing on a wave terrace
Which is NOT an example of ablation?
compaction
If water flows out the top of a well when the cap is removed, the aquifer in which the well is placed must be a(n)
confined aquifer
Groundwater pumping can cause the pressure in an aquifer to be reduced, resulting in a settling of the overlying layers downward. This is the most typical of pumping from what type of aquifer?
confined aquifier
The mineralogy of a shale is found to have been altered by the heat generated from a nearby dike. Which term most accurately describes the process the shale underwent?
contact metamorphism
Loess deposits in Mississippi are believed to have come from
continental glaciers
A gently sloping platform sits off the coast of most continents. This feature is known as a(n)?
continental shelf
Starting on land and moving into the ocean, which list is in the correct order?
continental: shelf, slope, rise
The formation of an atoll involves
contraction of island as it cools and growing reef
Overthrust faults are common in what tectonic environment?
convergent boundaries
Where are the deepest earthquakes likely to originate?
convergent boundary between two oceanic plates
Thrust faults are typically associated with tectonic
convergent zones
Rain occurs when an air mass containing water vapor is
cooled
Atolls are ring shaped islands in the ocean. What are the rings made of?
coral
If a bucket of water and soil is shaken and then allowed to sit, how will the sediment appear after it has all settled to the bottom?
course sediment on the bottom, fine sand on the top
Which phenomenon can result in an increase in the elevation of a stream channel?
creation of an alluvial fan
A wall is toppled over as the result of slow, relatively uniform movement of soil down a slope. This is an example of what type of mass wasting?
creep
Which is likely to result in property damage, but not likely to cause injury to people or animals?
creep
Which is the slowest form of mass wasting?
creep
Which is the slowest type of mass wasting?
creep
Which evidence of wind blown deposits?
cross-bedding
An igneous dike appears in a sandstone layer. What principle can be used to argue that the sandstone must be older than the dike?
cross-cutting relationship
Unconsolidated material flows extremely fast down a deep slope. This event would be best characterized as
debris avalanche
Seismic waves attenuate away from the epicenter. What does attenuate mean?
decrease in energy
Where would you expect to find pelagic sediments?
deep ocean floor
In some areas, the elevation of the ground surface is decreasing as wind removes fine particles and carries them away. This process is known as
deflation
Distributaries are common features in which environment?
delta
Distributaries are commonly found in
deltas
Where are distributaries typically found?
deltas
Turbidity currents are
dense flows of water and sediment down ocean or lake slopes
Levees are created when flood waters
deposit coarse material where they first spill out of the channel
Which is the correct spelling for a dry region?
desert
In desert conditions, wind tends to pick up fine material and leave behind larger ones. This process results in the creation of?
desert pavement
What are index fossils primarily used for?
determine the age of the strata in which they are found
Processes affecting sediments after they are deposited are called?
diagenesis
Which condition favors the formation of a delta?
discharging river with high sediment load
A river will often divide up into several smaller channels at a delta. These smaller channels are called
distributaries
What feature is typically associated with deltas?
distributaries
When a river forms a delta, the river often eventually divides into numerous smaller streams that discharge into the lake or ocean. These streams are called
distributaries
Tensional forces are most likely produced at what type of tectonic boundary?
divergent
Potable water is
drinkable
The "Dust Bowl" created during the 1930's resulted from a combination of
drought, tilled soil, wind
The addition of water could increase the stability of a slope consisting of
dry sand
A rock that bends without breaking is called
ductile
A rock that folds under pressure rather than fault is referred to as
ductile
A rock that tends to bend or fold easily is called
ductile
Which bedform indicates the fastest flowing water?
dunes with ripple marks on top
Varves are alternating fine and course-grained glacial deposits. The course grained layers are typically deposited
during the summer when the glacier is melting
What can cause liquefaction of saturated sand or silt?
earthquake
Which is typically required to produce liquefaction of saturated sands?
earthquake
As plates slide past one another, rock on either side of a vault is flexed. When the fault ruptures, the rock snaps back into its original state. This phenomenon is known as
elastic rebound
As tectonic plates move, rocks along faults will bend under the strain until the fault suddenly ruptures and the rocks on either side snap back into their original shape. This phenomenon is known as
elastic rebound
Rocks bowed by shear forces along a fault boundary will snap back into place once the fault ruptures. This is known as?
elastic rebound
Sediments accumulated by wind are referred to as?
eolian
Which term refers to deposits formed by wind?
eolian
The surface location directly above the focus of an earthquake is known as the
epicenter
Installation of a dam along a river will change the longitudinal profile resulting in
erosion of the river below the dam
A large boulder of limestone is found sitting on top of granite, and the closest limestone outcrop is in mountains 50 miles away. If transported by a glacier, the boulder is referred to as a(n)
erratic
A large granite boulder is found sitting on top of a sandstone formation hundreds of miles from the nearest granite mountain. It is later determined the boulder must have been transported by an ancient glacier. The boulder is known as a(n)
erratic
A body of water is connected to the ocean, but supplied with freshwater from a river is called a(n)
estuary
Near the mouth of a small river, rising and falling tides create a mixing zone between seawater and fresh water that can extend hundreds of miles inland. This zone of mixed water is known as a(n)
estuary
Without surface tension in water
evaporation would be faster
A coastal lagoon is an example of what sedimentary environment?
evaporite
Which best describes a river with both high capacity and high competence?
fast moving, muddy river
Bedform dunes with ripple marks are an indication of
fast, turbulent flow
The ice valley in a glacier travels
fastest near the top and middle
If a rock formation breaks and one side moves up and the other side moves down it is called a?
fault
Residual ice left over from the previous season is called?
firn
Residual snow and ice that survives the summer season is called
firn
Snow on a glacier that remains through the summer and into the next season is called
firn
Natural levees are created by sediment deposition during
floods
A lahar is an example of
flow
A slope gives way and turns into a mass of jumbled debris that is partially buoyed by air. This type of mass wasting is best characterized as a debris
flow
Which general type of mass wasting tends to be the fastest?
flow
The _____ is directly below the epicenter of an earthquake
focus
The origin of an earthquake beneath the surface is the
focus
A rock that is ductile is more likely to ______ rather that fault
fold
A large region of folded beds is referred to as?
fold belt
A large slip of land that is highly folded (such as the Appalachians) is known as a
fold belt
A sandcastle that gets washed away by waves tossing up on a beach was located on the?
foreshore
Which term identifies the portion of the shore from the low tide mark to the top of the swash zone?
foreshore
Which has terms for water arranged by increasing salinity (increasing mg/L)?
fresh, brackish, saline, brine
Why do waves crest and break as they approach the shore?
friction along the bottom slows the front of the wave
Continental glaciers primarily flow
from thicker ice to thinner ice
Large garnet crystals have grown in mica schist. Which is considered a porphyroblast?
garnet
The study of landforms and the processes that make them is called?
geomorphology
Which would you expect to contain well sorted sediments?
glacial outwash
What is a fjord?
glacial valley flooded by the ocean
Of the choices below, what is the largest reservoir of water?
glaciers and the ice caps
Which is the largest reservoir of water?
glaciers and the ice caps
Which is a foliated metamorphic rock?
gneiss
Which of the following can be directly dated using radiometric dating techniques?
granite
Tides are caused by
gravitational pull of the sun and the moon
Which is often used to try to prevent beaches from eroding away?
groin
Which statement is true?
groundwater flow is generally laminar, stream flow is generally turbulent
Water continues to flow in a river even though it has not rained in two months. Where is the water in the river most likely coming from?
groundwater seepage into the river (base flow)
The half life of ^238U is 4.5 billion years. In the oldest known rocks on earth, how many of the original ^238U atoms are left?
half of them (50%)
Oceans tend to moderate climate near coastlines because water
has a high heat capacity
Which is most likely to result in land subsidence?
heavy pumping of groundwater
An unconsolidated sediment that can maintain a steep slope has a
high angle of repose
Compared to a small mountain stream, the Mississippi River has a
high capacity and low competence
The Mississippi River has
high capacity and low competence
The Mississippi River is a generally slow moving, muddy river. The Mississippi River has
high capacity and low competence
Large bodies of water tend to produce moderate climates in coastal areas. This is due to what unique property of water?
high heat capacity
Which condition favors turbulent flow?
high velocity
Compared to sand, clay usually has
higher porosity and lower permeability
Two intersecting cirques will form a
horn
What type of metamorphism is most likely to occur within the rock at the east pacific rise (a mid-ocean ridge)?
hydrothermal
Flow in continental glaciers is generally very slow, but is relatively fast in localized channels called
ice streams
Where is the Tonga Trench?
in the Pacific Ocean, east of Australia
"Quick Clays", such as found in Norway, were originally deposited
in the ocean
A stream that cuts deeply into underlying strata is known as a(n)
incised stream
Which will result in an increase in the size of waves?
increase distance over which wind blows
Which phenomenon is NOT used as an early warning of a major earthquake?
increase in landslide frequency (without detection of earthquakes)
Which will result in longer waves?
increased wind duration
What limits the height of a sand dune?
increased wind speed going over large dunes
An organism that existed for a short period of time in geologic history, but with widespread distribution is known as?
index fossil
You build a house on a slope. What can you do to minimize the risk of damage to your house due to slope failure?
install drains around the house to remove excess water
A horn, such as the famous Matterhorn, is formed by
intersecting cirques and aretes
What happens to a ^14C atoms when it decays
it turns into ^14N
A large chunk of glacial ice is partially buried by drift. The ice melts later leaving behind a(n)?
kettle
What is calving?
large chunks of ice breaking and falling off the end of a glacier
What combination will produce the fastest incoming tides? (i.e. moving inland the fastest)
large range between low tide and high tide, and gently sloping beaches
Poorly sorted sediments are generally __________ than well sorted sediments.
less permeable
Physical weathering of rock will tend to make a rock slope
less stable
A limestone cave is completely filled with water. The cave later dries up during a drought. After drying, the cave roof is.......
less stable because rock is more buoyant in water than in air
How much of the earths water occurs as fresh groundwater?
less than 1%
Which stream feature is created by repeated flooding events?
levee
Flood waters move more slowly outside of the stream channel. Sediments deposited from the slower moving water along the bank form ridges running parallel to the river. These elevated ridges are called?
levees
Parallel ridges on either side of a river are called?
levees
Which process describes saltation?
lifting of grains into current and settling out further downstream
Earthquakes can cause saturated sediments to become fluid resulting in collapse of overlying strata or structures. This phenomenon is called
liquefaction
Following an earthquake near Japan in 1964, intact apartment buildings suddenly sank into underlying sand layers. What phenomena caused this?
liquefaction
Vibration from an earthquake can turn saturated sand and silt deposits into a fluid. This phenomenon is known as?
liquefaction
Which mass wasting event typically required an earthquake to get it started?
liquefaction
During the 1964 earthquake in Alaska, a large section of land suddenly flowed seaward resulting in the destruction of dozens of homes. This resulted from the vibrational fluidization of underlying silt layers. This process is known as
liquifaction
Which is a wind blown deposit?
loess
Which is formed by both wind and glacial processes?
loess
Which sediment or rock type is typically formed by both glacial and wind action
loess
A cross section of a river system from its headwaters to its mouth forms a concave-upward curve known as its
longitudinal profile
Waves approaching a beach at an angle tend to produce
longshore currents
Spits are formed as a result of
longshore drift
Which process is responsible for creating spits
longshore drift
what process is responsible for the creation of a spit?
longshore drift
Which is an example of transpiration?
loss of water from plants into the atmosphere
What is typically found below the carbonate compensation depth (CCD)?
lots of silica ooze, but no carbonate ooze
A clear, fast flowing mountain stream has a
low capacity and high competence
The Mississippi River is a slow moving river that carries a huge mass of sediments. The Mississippi River has a
low competence high capacity
Slate is a
low-grade metamorphic rock
What is deflation?
lowering of ground surface due to erosion by wind action
In deserts, deflation refers to the
lowering of the ground surface due to removal of material by wind
What is a neap tide?
lowest annual high tide
Which magma type tends to produce higher grade contact metamorphism?
mafic
Which is a non-foliated metamorphic rock?
marble
The lower Mississippi River can be best described as
meandering
What type of river system often produces oxbow lakes?
meandering
The Mississippi River along the border of Mississippi is a good example of a
meandering stream
Seismic waves can NOT be utilized to
measure the velocity of a tectonic plate
Glacial till is found in a ridge where two glaciers had merged and flowed parallel to each other. What is the ridge known as?
medial moraine
A steep sided hill or mountain with a flat top is called a?
mesa
Rivers and wind carve their way into a a broad, flat lying desert. The first landforms to be created are _______, followed by ________ and __________
mesas, buttes, spires
A deeply buried sandstone is subjected to temperatures high enough to begin fusing the crystal grains together. The mineral and chemical composition of the rock remains unchanged. The rock is later uplifted and exposed at the surface. Which term best describes this rock?
metamorphic
________ are groupings of rocks of various mineral compositions formed under different grades of metamorphism from different parent rocks
metamorphic facies
The chemical alteration of an existing rock by reaction with dissolved material in water is known as
metasomatism
What part of a stream or glacier flows with the highest velocity?
middle
What phenomenon does the term longshore drift describe?
migration of beach sediment parallel to the coastline
A sand bank is the most stable if
moist
Which sand sample should have the largest angle of repose?
moist sand
Which will typically have the highest angle of repose?
moist sand
Why is wind less effective in moist climates?
moisture makes particles stick together
Which orientation of the earth, sun, and moon will produce the smallest differences between the low tide and high tide?
moon - earth - sun
Poorly sorted drift deposits along the edges of a glaciers are called
moraines
An air mass can be cooled to the point of condensing water vapor as a result of orographic lifting. Which describes orographic lifting?
movement of air over a mountain range
What does orographic lifting refer to?
movement of air over a mountain range
Which will settle to the bottom of a lake slowest?
mud
The lowest high tide occurs when the sun, moon, and earth form a right triangle. This tide is known as a
neap tide
Small fish tend to stay in the slower moving parts of the stream. Where are you most likely to find these fish? (select the best answer)
near the bottom of the stream
If ablation exceeds accumulation on a glacier, what will you expect to see?
net retreat of glacier
Does the principle of uniformitarianism mean that all geological processes happen slowly?
no
What tectonic activity could produce both an earthquake and a tsunami?
normal faulting on the ocean floor
Which type of faulting in the ocean floor is most likely to produce a tsunami?
normal or reverse
An earthquake that results in a tsunami was most likely created by
normal or reverse faulting
Which list is correctly ordered from the largest to the smallest reservoir of water?
oceans, polar ice caps & glaciers, groundwater, lakes & rivers, atmosphere
Stream sediments are most likely to be deposited
on the inside of a bend
On the Richter Scale, how much stronger is a magnitude 7 earthquake than a magnitude 5 earthquake?
one-hundred times as strong
Which glacial deposit would you expect to have fairly well sorted sediment?
outwash
How many measurable earthquakes occur around the world each year?
over 100,000
Approximately how many minor earthquakes occur around the world each year?
over 500,000
What features are commonly found on a meandering stream system?
oxbow lakes
An ancient glacier left behind striation marks. The direction of the glacier flow was _________ to the striation marks.
parallel
Orographic lifting refers to the lifting and cooling of an air mass as it
passes over a mountain range
If water travels very easily through a sediment, the sediment must have a high
permeability
The cleavage found in a slate or phyllite is generally
perpendicular to the main direction of the forces squeezing the rock
A bare slope made of unconsolidated sediments sits near the edge of a homeowners property. What could be done to make this slope more stable?
plant small, fast growing trees on the slope
How can you increase the stability of a bare dirt slope
plant trees on the slope
We can increase the stability of a moist, sandy slope by
planting grass and shrubs on sparsely vegetated areas
Water flows into a basin with no outlet. In the summer, the water completely evaporates leaving behind evaporite deposits over a broad, flat area called a
playa
An anticline whose fold-axis dips steeply into the earth is called a
plunging anticline
Folded strata that has been uplifted on one end is known as a
plunging fold
Large crystals contained in a fine grained metamorphic rock are called?
porphyroblasts
Drinkable water is also called?
potable
Drinkable water is called
potable
Drinkable water is referred to as?
potable
All the water in rivers and lakes ultimately comes from
precipitation
What is a synonym of rainfall?
precipitation
Why are the "Dust Bowls" of the 1930's no longer common in the US
prevalent use of irrigatoin now
Which is likely to have the highest porosity?
pure sand
What was responsible for the mass wasting event in Rissa, Norway that carried several farms off into a lake?
quick clay
Uranium decays into a series of daughter products, one of which was discussed in chapter 9 (geologic time) as an environmental hazard that can accumulate in homes without the owner being aware of it. This discussion refers to
radon
What is ultimately the source of all river, lake, and groundwater?
rain and snowfall
Atolls are characterized by a ring of exposed or nearly exposed land surrounding shallow water, usually in tropical oceans. What is the ring typically made of?
reef
Terraced floodplains are typically an indication of what geologic phenomena?
regional uplift
Cross-cutting relationship is an example of _____ dating
relative
Strata X is determined to be younger than strata Y because X sits on top of Y. This is an example of
relative dating
The _________ is the difference between the highest and lowest elevations of a particular area
relief
Where do we find the highest variation between high and low tide?
restricted bays such as the Bay of Fundy
Which is the best description of a bed load?
river-bottom sediments that are traveling downstream
Which is typically the fastest?
rock slide
Which describes the disaster at the Vaiont Dam in Italy in 1960?
rockslide into reservoir sent wave over dam resulting in severe flooding downstream
Water in a river moves more slowly along the bottom than the top because of?
saltation
Which term can refer to the way sand is transported along both a river bottom and along the surface of a sand dune?
saltation
Wind will move sand along near the ground surface by a process called?
saltation
Under normal conditions (excluding hurricanes and tornadoes), what is the largest size particle that wind can transport?
sand
A calculation of the inputs and outputs to a beach by sedimentation and erosion is called a
sand budget
Which is an eolian deposit?
sand dune
Which is likely to be the most permeable?
sand with 30% porosity
Which will have a higher permeability?
sand with 35% porosity
What combination of sediments and events can lead to liquefaction?
saturated sand layers and an earthquake
Which is a foliated metamorphic rock?
schist
Which feature would be most common along an active continental margin?
sea cliffs
An ocean volcano that is completely submerged is called a(n)
seamount
An underwater volcano is called a
seamount
Which is an example of slump?
sediment along a riverbank breaks away and moves downward as a unit
What happens to the suspended load when a river discharges into a quiet lake?
sediment settles to the bottom
The principle of original horizontality means that
sedimentary formations were deposited horizontaly
The time elapsed between major earthquakes is used as a means of estimating when the next major earthquake will occur. This method is called the
seismic gap method
Sedimentary layers are often deposited in units that are separated by erosional surfaces. As an example, sediments may be deposited in the ocean at the end of a river during a period of high sea level. When the sea level later falls, some of the older sediments are eroded and sediments start depositing further out into the ocean. Studying ancient sedimentary units such as these to try to understand what happened is known as?
sequence stratigraphy
Which rock could turn into a slate? (give the best answer)
shale
A horizontal layer of igneous rock is found between to layers of sandstone. The crystals in the igneous rock are large enough to see. Both upper and lower sandstone layers show evidence of being heated. What would you call the igneous rock?
sill
Which could be caused by heavy pumping from a single groundwater well?
sinkhole formation
DNAPL is found contaminating an aquifer. Where is most of the DNAPL likely to be found?
sitting at the bottom of an aquifer
Ten years after installing a fence on a hill slope, all the fence posts are leaning downhill. What type of mass wasting is causing this?
slide
Earthquakes are often associated with a sudden displacement along a fault. The distance traveled during the displacement is called the
slip
Which bedform results from the fastest moving water?
smooth, flat sediment
Slow flow of saturated soil over permafrost is called
solifluction
Slow movement of saturated soils, particularly in arctic regions, is known as
solifluction
Which of the following is the slowest moving phenomenon?
solifluction
Which is the most intensely eroded?
spire
A column of erosion resistant rock sitting out on a wave terrace is called a
stack
Which has been used as a warning that a large earthquake may soon hit?
strange animal behavior
Parallel lines carved by a glacier in the underlying bedrock are called
striations
What type of fault is the San Andres fault in southern California?
strike-slip
Which type of faulting could cause an earthquake, but would NOT typically cause a tsunami?
strike-slip fault
Earthquakes with the deepest focus tend to occur along or at
subduction zones
Which phenomenon could produce a tsunami?
submarine landslide
What is the wave terrace?
submerged, flat regions along the coast eroded by wave action
A layer of sandstone sits above a layer of shale. It is assumed that the sandstone must be younger than the shale. This assumption is based on the principle of
superposition
In undisturbed strata, older sedimentary rocks will always lie beneath younger sedimentary rocks. This statement is known as the principle of
superposition
Younger sedimentary rocks form on top of older rocks. Which principle does this refer to?
superposition
Damp sand can maintain a deeper slope than dry sand. The attractive force between water and sand particles is due to
surface tension
Where does the water in hydrothermal springs and geysers typically come from?
surface water that percolated down to a hot zone; heated water rises to the surface
Which are the slowest type of seismic waves?
surface waves
Which list is ordered from slowest to fastest (left to right) seismic waves?
surface, S, P waves
Rocks that have fallen from steep slopes typically collect near the base of the slope, or where the slope is not as steep. This loose collection of rocks is called.
talus
Which does NOT have a significant impact on the size of waves?
temperature of the wind
What type of forces are exerted at a tectonic divergent zone?
tensional
Fact: The US Army Corps of Engineers has spent enormous sums of money and manpower strengthening the levees along the Mississippi River. Question: Is the height of the current levee system natural, or has the Corps greatly increased the height above what natural processes could ever accomplish
the Corps has greatly increased the height
The seismic gap method refers to earthquake prediction based on
the average length of time between major earthquakes
The highest tide (spring tide) occurs when?
the earth, moon, and sun form a straight line
The point on the surface of the Earth directly above the focus of an earthquake is known as
the epicenter
A terminal moraine represents
the farthest place the glacier ever advanced
How is subsidence different from deflation?
the ground sinks during subsidence; the ground is blown away during deflation
An igneous rock is dated and said to be 120 million years old. What is meant by this?
the magma solidified 120 million years ago
Why is there an elevated ridge along mid-ocean spreading centers?
the ocean floor rock is hot and expanded there
In the context of earthquakes, "slip" is
the offset created when one side of a fault block slides past the other
What do terraced floodplains indicate?
the region has been uplifted
A river is found that cuts through the river of a mountain range. Which is most likely true?
the river was present before uplift of the range
Kettles form when blocks of ice are left behind a retreating glacier and are buried in a sediment. Why dont the ice blocks melt as fast as the glacier?
the sediment insulates the ice blocks
Major earthquakes in a certain location tend to occur at regular intervals of time. Predicting the next earthquake here would most likely rely on
the seismic gap method
What happens when a portion of a fault ruptures?
the stress on the unruptured portions of the fault increase
Flood waters lose much of their sediment load when they spill over their banks because
the water does not move as fast outside the channel
What can be accurately said about waterfalls?
they tend to migrate upstream
What contributed to the formation of the "Dust Bowl" in the 1930's?
tilled sand, drought, and wind
The fastest moving area of a river will generally be found near
top and middle
When referring to water quality, what does TDS stand for ?
total dissolved solids
Which terms are types of drainage networks?
trellis and dendritic
A small river that dumps into a large river is known as?
tributary
A steady wind will produce larger waves if it blows for two days than it will if it blows for only one day
true
A dense flow of sediment and water down a slope in the ocean is known as a(n)
turbidity current
Which type of flow results in more erosion of a stream bed?
turbulent
Which phenomenon could NOT result in an older rock sitting on top of a younger rock?
turbulent deposition resulting from turbidity currents
There are three different terms to identify three different types of unconformities. Which is NOT one of the three terms?
ultraconformity
Sediments that are not lithified are referred to as
unconsolidated
The intensity of the seismic waves felt in a town 100 miles from the epicenter of an earthquake will be the most severe if the region is underlain by
unconsolidated sediments
Where are you most likely to find metamorphic rocks that were produced by high temperature, but relatively low pressure?
underneath a lava flow
A deep hole does not contain any water several days after it was dug. This whole must be completed in the
unsaturated zone
The age of some rocks can be determined by measuring the ratio of ^238U to ^206Pb in a mineral. How do geologists know that there wasn't ^206Pb in the mineral when it was first formed?
uranium minerals exclude lead during crystalization
Hanging valleys are commonly associated with?
valley glaciers
Sand dunes will have difficulty forming if
vegetation grows quickly
What is relief?
vertical distance between the highest and lowest points
Flow in a stream will generally be laminar only if the flow is
very slow
The center of an atoll is often below water. Which does NOT cause this?
volcanic lava flows
Most of erosion and depositions in deserts is caused by
water
Why can water make a rock slope less stable?
water can lubricate fractures
Why is rock more buoyant in water than air?
water is more dense than air
A cone of depression forms when?
water is pumped from a well
When digging a hole in the ground, how do you know when you have hit a saturated zone?
water will flow into the hole
Why is a cave roof more stable if the cave is filled with water?
water will partially support the roof of the cave
Why is a bay a better place than a point for storing a boat?
wave refraction dissipates wave energy in a bay
A flat, submerged surface created by wave action along a coast is known as?
wave terrace
Longshore currents are caused by
waves hitting the shore at an angle
What is swash?
waves that wash up onto the beach
Which is NOT an example of mass wasting?
weathering
What greek character is typically used to designate wave length?
weird h
Which will make the best aquifer?
well sorted sand
The quick clay flow observed in class in the film clip from Rissa, Norway started
when a farmer plied excavated soil on top of the clay at the lake edge
A crevasse in a glacier is most likely to form
where it turns a corner
What makes a fossil a good index fossil?
widespread geographical distribution and short history of existence
The term eolian refers to rock or sediment deposited by?
wind
The term eolian refers to sediments deposited by
wind
Which produces the most well sorted sedimentary deposits?
wind
Which does Not affect the size of waves on the ocean?
wind direction
What is required to form sand dunes?
wind, dry climate, source of sand.
Where would you expect the largest distance between low tide and high tide to be found?
within a long, narrow, bay
What is the principle of superposition?
younger sediments are deposited on top of older sediments