ESC 1000 Final
If a 50-year flood occurs on the Mississippi River this year, what is the probability that a flood of the same magnitude will occur in the following year?
2%
Sea level is currently rising at 3.3 mm/year, and scientists predict that global warming could cause a rise in sea level of 7 m if left unabated. How long will it take the sea to rise 7 m at the current rate?
2,121 years
What is the average percentage of dissolved salt in seawater?
3.5%
Approximately what percentage of the Earth's surface is covered with ocean water?
70%
What is an ephemeral stream?
A desert stream that contains water only immediately following a rain event.
Adding a small amount of water to a substance increase its cohesion; whereas, adding a lot of water decreases its cohesion. Why?
A small amount of water increases surface tension and holds the grain together. Too much water between the grains will eliminate surface tension.
The figure below shows two hypothetical streams that have identical cross-sectional areas but different channel shapes. Assuming all other factors are equal, stream ________ will have the fastest flow because of the difference in ________.
A; wetted perimeter
Which river has the greatest discharge of any stream on Earth?
Amazon
Which statement about desert life is correct?
Animals that live in the desert must have the ability to retain water and survive extreme temperatures, is correct.
For several generations, your family has lived on a farm with a water well. There has never been a problem with the water supply in the past; however, your well has now gone dry. There are several small farms nearby and a large, growing city 50 miles to the north. What can you conclude is the most likely reason for your well to become dry?
As the city grew larger, more wells were drilled and water was over pumped, thus lowering the water table.
In the figure below, which letters represent the wave height and wavelength?
B and E
Identify the failure surface in the image below.
C
Identify the toe of the slump in the image below.
D
Imagine that some of the wells around a city have begun to show elevated levels of a toxic substance. Without knowing what the toxic substance is, how can you determine what the source of the chemicals might be?
Determine which wells show the chemicals and which do not and use that data to track theflow of the water.
In many areas with karst terrain, people use sinkholes as places to dump garbage. What effect might this practice have on the groundwater supply?
It could contaminate the groundwater in any or all aquifers in the area.
Consult the figure below. What will eventually happen to the Everglades if the people of Miami and Fort Myers do not stop using the water?
It will eventually dry up and disappear.
Imagine you have a layer of limestone with high porosity but low permeability. What can you do to increase its permeability to allow water to be pumped from the layer and used as a source of drinking water?
Remove the overburden so that there will be less pressure trapping the water.
You are testing the groundwater quality of an aquifer and find that it has high amounts of arsenic. What is the likely source?
The arsenic comes from the dissolved minerals in the aquifer rock
You have a choice to drill your water well into a shallow unconfined aquifer or a deeper artesian aquifer. Drilling deeper will cost more money; nevertheless, you chose to drill into the artesian aquifer. Why?
The artesian aquifer will flow on its own, without a pump.
You have a choice to drill your water well into a shallower unconfined aquifer or a deeper confined aquifer. Drilling deeper will cost more money; however, you choose to drill into the confined aquifer. Why?
The confined aquifer will contain more water.
You are a geologist trying to determine if the slope your client's house sits on is stable. You determine that the angle of repose of the hillside is 35°. Which of the following situations would be considered stable?
The slope is composed of dry sand.
Why does the removal of material at the base of a slope decrease its stability?
The slope now exceeds the angle of repose.
The porosity of vesicular basalt is about 25%; however, when water is poured on it, the water does not come out the other side. How is this possible?
The vesicles in basalt are not connected, so it has no permeability.
Why does an artesian well flow without pumping?
The water in a confined aquifer is pressurized.
Why do submarine slumps pose a hazard to people living in coastal areas?
They can trigger tsunamis
What will eventually happen to the headlands in the figure below?
They will become a straight line of cliffs as rock is eroded away.
The deserts found in the western United States are primarily the result of being located _______
Within the rain shadow of one or more mountain ranges
Which of the following situations would be the least susceptible to slope failure?
a gently sloping hill in a dry desert region
What physical property of the underlying rock would lead to the formation of a cliff over which a waterfall may form?
a high resistance to erosion
When fine-grained sediment is blown away as shown in the figure below, the coarser sediment left behind is known as ________.
a lag deposit
Which of the following situations would be the most susceptible to slope failure?
a large resort built on top of a cliff directly above the ocean
you are running a sonar survey to map the bathymetry of an ocean basin. Using the following continuous sonar data giving the depth of the seafloor in meters, what feature have you just discovered?
a mid-ocean ridge
Which of the following situations is the most likely candidate for the occurrence of mass movements?
a mountain terrain in a humid environment
Deserts represent ________ of the Earth's land surface.
about 25%
A coast that grows seaward as a result of regular sedimentation is a(n) _______
accretionary coast
Which of the following factors decreases the risk of mass movement?
adding vegetation to the side of a hill
A(n) ________ consists of sand and gravel deposited by ephemeral distributary channels that occur where a gully or a canyon discharges from its mouth.
alluvial fan
An apron shaped pile of alluvium that forms at the mouth of a canyon is known as a(n) ________.
alluvial fan
Porosity is best described by which of the following?
amount of open space in a rock or sediment
_______ occurs when debris or snow mixes with air to form a chaotic cloud.
an avalanche
Talus aprons represent accumulations of ________.
angular debris at the base of a hill
For a well to function properly, it must be drilled below the water table and into a(n) _________.
aquifer
If an intrusive igneous rock is unfractured, it serves as a(n) ________ in local hydrogeology.
aquitard
The definition of a desert depends on a region's ________.
aridity
Major oceanic surface currents travel ________.
at an angle to prevailing winds as a result of the Coriolis effect
Over time, alluvial fans may merge to form a ________.
bajada
The lowest elevation to which a stream can downcut is the ________.
base level
The form and topography (depth profile) of the ocean floor is termed ________.
bathymetry
Why is a spring tide so much higher than a normal high tide?
because the Sun is aligned with the moon
In some cases, the push of flowing water can break chunks of solid rock off of the channel bed. These pieces are then carried along by a stream as _________
bed load
The ________ in the sequence of sedimentary rocks shown below may become a failure surface
bedding planes
Calcrete (caliche) forms in a desert climate through the dissolution and the re-precipitation of ________ during and after rainstorms.
calcite
Moisture among sediment grains ________.
can promote stability if present in small amounts
Which of the following is NOT true? A 100-year flood ________.
cannot occur in successive years
Which of the following hazards could lead to desertification?
climate change
Surface currents flow __________ in the Northern Hemisphere and __________ in the Southern Hemisphere.
clockwise; counterclockwise
The figure below illustrates the formation of a ________.
coastal desert
A(n) __________ is a vegetated, flat -lying stretch of coast that floods at high tide, becomes particularly exposed at low tide, and does not feel the impact of strong waves.
coastal wetland
Swamps and marshes are examples of __________.
coastal wetland
Coastal region deserts are most likely near ocean currents that are ________.
cold
A desert may form along a coastline because a ________.
cold current cools and dries the air
Thermohaline circulation carries ________ water from the poles to the equator, where the water becomes ________.
cold;warm
Geologists distinguish among different types of mass wasting based on factors such as the ________ of the moving material and the rate of movement.
composition
The shallowest portions of an ocean found along the margins of continents are the ________.
continental shelves
The Florida coast is an example of a(n): ________.
continental slope
which portions of the sea floor are most steeply sloped
continental slopes
Most hot deserts ________.
cool off greatly at night because of sparse vegetation, dry air, and little cloud cover
Tree trunks that have a pronounced curvature at their base are indicative of ___________
creep
Which of the following types of mass movement takes place most gradually?
creep
The outer edge of a meander, where material is being eroded, is a(n) ________.
cut bank
Weathering is a failure trigger because it ____________ of the material.
decreases the strength
The process of lowering the land surface by wind erosion is known as ________.
deflation
In uniform sediments with a relatively constant and gentle slope at the surface, a ________ drainage network is expected.
dendritic
The figure below shows an example of a ________ drainage network.
dendritic
Compared with the continental crust, the oceanic crust is ______ __.
denser
Conversion of productive land to desert is known as ________.
desertification
A flowing artesian well is one that ________.
discharges groundwater at ground surface without pumping
Running water dissolves soluble minerals. This material is most likely to be transported by a stream as _________.
dissolved load
Which of the following human activities will lead to desertification?
diversion of water from an area
A coastline characterized by steep- sided cliffs and associated with an active margin is likely to be __________.
emergent
When the sea level rises, an ocean may invade a river valley, producing a nearshore body of water of mixed and variable salinity termed a(n) ________.
estuary
As shown in the figure below, ________ may form parallel to slope surfaces in granite and become a failure surface
exfoliation joints
Which of the following increases the risk of mass movement?
flooding the sediment with water to the point of saturation
Rip currents ________ the shoreline.
flow directly away from
Longshore currents ________ the shoreline.
flow parallel to
A stream is ________.
flowing water confined to a channel
Pirate streams ________.
form when headward erosion causes one stream to intersect another
A periodic explosive eruption of steam and water from within the ground up through the surface is termed a(n) ________.
geyser
The slope of a stream surface measured between two points along its course is the ________.
gradient
Mass movements are driven by __________.
gravity
The immediate cause of incidents of mass movement is ________.
gravity
Runoff from farm fields entering a stream system is likely to be __________ than that from naturally vegetated fields.
greater and sediment laden
As a rule, groundwater always flows from areas of ________.
greater hydraulic head to those of lesser hydraulic head
During heavy rainstorms, rates of physical weathering and erosion are ________.
greater in deserts than in humid climates because soil tends to be more easily eroded in deserts than in humid regions
Because of wave refraction, erosion along an irregular coastline is ________.
greatest along headlands
The majority of liquid freshwater within the Earth exists in ________.
groundwater
The water table surface mimics the topography in an area because ________.
groundwater flow rates are so low
The major surface currents on Earth that display a circle-like path and follow the ocean basin margins are known as __________.
gyres
Meandering streams ________.
have a channel that is highly sinuous (curvy)
Ephemeral streams ________.
have flowing water either episodically or during a portion of the year
Water in a stream flows from its _________ to its __________.
headwaters, mouth
High tide during a full moon will be ________.
higher than normal
The region below a streambed where groundwater flows in the same direction as the stream but at a slower rate is termed the ________ zone.
hypoheic
Where would you expect to find geysers?
iceland
A coral reef would MOST likely be found
in the shallow waters surrounding a tropical volcanic island.
The Sahara is a desert primarily because it is located ________.
in the subtropics
Along beaches, groins have
increased erosion rates immediately down current from the groin
After extensive erosion of a hill in a desert environment, the small remnant surrounded by alluvium filled basins is known as a(n) ________.
inselberg
What is the most effective means of mitigating the risk of a slope failure for slope shown in the figure below?
installing riprap
Slumps typically arrive ________ at the bottom of a slope.
intact
The stream gradient of most rivers ________.
is greater near the source than near the mouth
Which of the following is true of beach nourishment as a solution to coastal erosion?
it is costly and may only provide a temporary solution
The majority of caves are formed by the dissolution of bedrock ________.
just below the water table
Topography dominated by depressions formed by the collapse of caves is termed a ________.
karst landscape
The principal difference between a lahar and a mudflow is the ________.
lahar contains pyroclastic debris from a volcanic eruption
Well-rounded sand has an angle of repose __________ that of irregularly shaped gravel
less than
Ground shaking can transform wet sediments into liquid-like slurries in a process known as ________.
liquefaction
Fine grained, wind blown sediments are eventually deposited as ________.
loess
The Dust Bowl event in 1933 resulted from which natural event?
long-term drought
An aquifer has ________ porosity and ________ permeability.
low, high
The sea surface salinity is ________ at the mouth of the Amazon River and ________ in the Dead Sea.
low; high
Rates of groundwater flow are ________ than stream flow because the water ________
lower; must make its way through tiny pore spaces
Pumping vast quantities of water locally ________.
lowers the local water table, forming a cone-shaped depression
V-shaped stream valleys result from the downcutting of stream erosion and ________
mass wasting on the valley sides
If a material is porous, it ________.
may be permeable or impermeable
The elevation of the water table ________.
may rise during rainy periods and sink during droughts
Very hot air just above the ground creates a wavering pool of light on the ground known as a(n) ________.
mirage
Construction workers often cut benches or terraces, such as those seen in the image below, along the sides of roads to help mitigate landslides. This is because terraces
mitigate slope failure by removing weight from the hillside
Which of the following types of mass movement is least coherent (most like a fluid)?
mudflow
If a material is highly permeable, it ________.
must either have substantial porosity or be fractured
At the equatorial ocean basins, sea surface temperatures may reach 25°C or greater. What is the range of temperatures for the seafloor, approximately 4-5 km below?
near freezing (1°C-2°C)
The Gobi in Mongolia is a desert primarily because it is located ________.
near the center of a large continent
The Atacama Desert in Chile is a desert primarily because it is located ________.
next to a cold ocean current
Runoff is NOT commonly derived from ________.
ocean currents
Within a meander, where is sediment most likely to be deposited?
on the inner banks of the meander
The rate of groundwater flow per unit area through a body of rock or sediment depends ________.
on the slope of the water table and the permeability of the rock or sediment
A meander that is cut off to become completely isolated from the main channel but which retains water is a(n)
oxbow lake
Along a uniform and steep slope of relatively weak substrate, a ________ drainage network is expected.
parallel
The figure below shows an example of a ________ drainage network.
parallel
Which type of drainage network is associated with badlands topography?
parallel
You are drilling a water well when you hit water at a much shallower level than you expected. What have you likely found?
perched aquifer
Material through which water readily flows is termed _ _______.
permeable
The inner edge of a meander, where sediment is deposited, is a(n) ________.
point bar
Land subsidence is likely when ________.
pumping lowers the water table
Along a large cone-shaped volcano, a ________ drainage network is expected.
radial
The measured rainfall shown in the figure below is characteristic of a ________.
rain-shadow desert
In a region with prominent orthogonal sets of joints, a ________ drainage network is expected.
rectangular
The figure below shows an example of a ________ drainage network.
rectangular
The process of reef bleaching occurs when __________.
reefs lose their color and die in response to warming of seawater
Waves ________.
refract so as to impact the shore in a nearly parallel manner
The most important factor in determining if an area will be subject to mass movement is
relief
Which of the following consist(s) of large boulders placed at the base of coastal slopes?
riprap
________ can occur where undercutting by waves removes support from beneath cliff overhangs.
rock falls
Native Americans produced petroglyphs by etching into ________.
rocks that had been coated with desert varnish
A salt encrusted muddy tidal flat is known as a ________.
sabkha
Evaporite deposits in coastal, subtropical regions derived from the evaporation of seawater stranded above high tide are termed ________.
sabkha
In the figure below, the sand grains are being transported by ________.
saltation
A ________ may form at the head of a slump
scarp
Vegetation in the desert consists of ________.
scattered succulents, such as cacti, with adaptations to obtain and retain as much water as they can
Which of the following features is characteristic of a rocky coast?
sea stacks
The dissolution of rock produces ________.
secondary porosity
What is happening to the hillside in the tundra pictured below?
soliflutcion
Any place where groundwater naturally flows out of the Earth's surface is termed a(n) ________.
spring
Areas with relatively scarce sand and constantly shifting winds will develop ________ dunes.
star
Which type of coastline would most likely contain estuaries or fjords?
submergent
The most expansive hot deserts on the Earth occur in the ________.
subtropics, between 20° and 30° north or south of the equator
Most of the erosion in desert environments is caused by ________.
surface water
Fine-grained sediment, such as dust and silt, can stay in the air and be transported by wind in ________.
suspension
Notice the newly constructed seawall in the illustration below. The most likely outcome of its construction is that the seawall will __________.
temporarily protect the cliff from beach erosion
The deepest part of a curved stream channel, where the flow is fastest, is called the ________.
thalweg
Liquefaction is most likely to occur in which type of area?
the coast of California
Hot springs can be formed by the heating of groundwater by magma or by ________.
the geothermal gradient
Hot groundwater is mineralized because
the hot water dissolves minerals
The Coriolis effect causes the apparent deflection of currents as a result of
the rotation of the earth
The principal difference between a slump and a debris slide is ________.
the shape of the path taken by the moving mass
The hydraulic gradient in Darcy's Law is essentially the same as which of the following?
the slope of a line
Which of the following scenarios is more likely to cause a flash flood than a slow-onset flood?
the sustained presence of a storm over a region
A person is digging a hole, when the hole suddenly starts to fill with water. What have they found?
the water table
Which of the following is NOT an adaptation of plants that helps them survive in deserts?
thin-skinned seeds that can quickly germinate when it rains
Compared with the continental lithosphere, the oceanic lithosphere is ________
thinner
The geometry of sand dunes is NOT strongly influenced by the ________.
timing of the monsoon season
How can you use a landslide hazard map to help buy a piece of property?
to determine if the property is in a high-risk zone for landslides
In the figure below, which way is the wave moving?
to the right
The figure below shows the Dakota and Ogallala aquifers along with interlayered shale deposits. What likely occurred in the area to produce the alternating shale and sandstone layers?
transgression and regression
In a region characterized by a parallel series of ridges and valleys, a ________ drainage network is expected.
trellis
The figure below shows an example of a ________ drainage network.
trellis
The primary stream fed by tributaries within a dendritic drainage network is termed a ________ stream
trunk
In a _________, submarine sediments flow chaotically downslope in submarine canyons.
turbidity current
A(n) ________ aquifer is more likely to be contaminated than a(n) ________ aquifer.
unconfined; confined
Rock or sediment between the water table and the land surface represents a(n) ________.
unsaturated zone
Which of the following scenarios is most likely to result in an emergent coast?
uplift associated with active margin tectonics
Lahars occur on ________.
volcanic slopes
The downslope movement of which of the following materials does NOT constitute a mass wasting event?
water
Slope failures are most likely to occur in ________ conditions.
wet, mountainous
The shape of a delta is primarily determined by ________.
whether river currents, wave-driven currents, or tidal currents are locally predominant
As shown in the figure below, wind erosion can create a faceted rock known as a ________.
yardang
