Geology Final (part 2)
Using the figure below, which of the following list correctly identifies the various seafloor landforms
A=Continental shelf B= continental slope D=continental rise G= abyssal plain C=mid-ocean ridge F=trench E=volcanic arc
Natural carbon sinks have generally matched the production of carbon dioxide until
Approximately 1900
which chemicals are part of the carbon cycle?
CH4 methand, HCO3 Bicarbonate, and CaCO3 calcite
How are carbon dioxide levels in the atmosphere affected by tectonic uplift of rocks and their resultant chemical weathering?
CO2 is removed from the atmosphere
The warmest global temperatures since the last ice age occurred in the _____
Holocene Maximum, approximately 6,000 years ago
You have just bought your dream home along a coastline, but you notice that the beach in front of your new house is slowly disappearing. You decide to solve this by building a groin. Winds blow predominantly from east to west, so where do you pillage your groin?
Perpendicular to the shore to the east of your house
As the velocity of flow decreases, which of the following is NOT true?
The competence increases
Rip currents ________ the shoreline.
flow directly away from
Bioturbation is the
mixing of sediment by burrowing organisms
Which type of drainage network is associated with badlands topography?
parallel
Which river is a threat to capture the flow of the Mississippi River through avulsion and stream piracy?
the Atchafalaya River
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 3.3mm/yr and scientist 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
Models used by the Intergovernmental Panel on Climate Change show that by the year 2100, the sea level may rise by as much as
20-60 cm
What is the percentage of dissolved salt in seawater?
3.5%
Models used by the Intergovernmental Panel on Climate Change show that by the year 2100, the average annual temperature will have increased in some parts of the world by as much as ________.
4.c
Approximately what percentage of Earth's surface is covered with water?
70%
The reliable paleoclimate record from the Antarctic and Greenland ice cores provides information back to approximately ______ years ago
700,000
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 of difference in ______
A;wetted perimeter
How does the formation of oil shale deposits, coals, and limestone effect the carbon dioxide?
All three decree the total co2 in the atmosphere
Which river has the greatest discharge of any stream?
Amazon
A crater in Mexico's Yucatan peninsula is about the right age to be a result of an impact that brought about the extinction of numerous species at the end of the ____________ Period.
Cretaceous
In uniform sediments with relatively constant and gentle slope at the surface, a _____ drainage network is expected
Dendritic
How are pollen species used to interpret ancient environments?
Different plant species live in different climates
How are greenhouse gases like carob dioxide and methane different from other atmospheric gases like nitrogen and oxygen?
Greenhouse gases are more efficient at absorbing thermal energy and re-radiating it than the other atmospheric gases
Mid-ocean ridges (MORs), which are the sites of new oceanic crust formation, are linear mountain chains that run along divergent plate boundaries. Why does an MOR sit up higher than the surrounding oceanic crust?
Hot materials are less dense and expand, this the new crust will sit higher than the surrounding crust
The entire state of Florida is composed of fossiliferous limestone, what does this imply about Florida during the recent past?
It was a submergent coast
If a dam is installed across a river, what effect will this have on the coastline?
It will starve the coast of sediment, and the beaches will disappear.
If the wind is blowing parallel to a coast, will it create an upwelling current or downwelling current?
Neither; it will enhance the longshore current
Why do ocean water and sea ice have very different effects on air temperatures?
Ocean water absorbs solar energy much more effectively than sea ice
Which process removes carbon dioxide from the atmosphere?
Photosynthesis
if sea level continues to rise and covers the city of Miami, the Florida coast will become a
Submergent coast
You are a coastal geologist trying to help a coastal community restore its sediment-starved beach. You decide that beach nourishment is the best option, so you order that dredge sediment from the nearest river be placed on the beach. The sediment is 70% silt and 30% sand. What will be the effect of using this sediment?
The slit will be washed away by the waves, leaving the beach no better off
How would the Coriolis effect affect the space station?
The space stations would not be affected because it is not in Earth's atmosphere.
Why is the surface saltine in the tropics so much higher that of the equator or high latitudes?
There is a higher evaporation rate and lower rate of precipitation in the tropics
What will eventually happen to the headlands in the figure below?
They will become a straight line of cliffs as a rock is eroded away
Which of the following is an important long-term (i.e., spans tens of millions of years) factor in global climate change?
Variation in milankovitvw parameters
Scientist believe that approximately 60 million years ago the closing of the Isthmus of Panama changed the climate of Earth so severely that winters in Europe became 10.c warmer than they had been. Why did this happen?
Warm Caribbean Sea waters were forced up into the North Atlantic Ocean
What is the difference between weather and climate?
Weather is a transient condition,wheras climate is a long-term cycle
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
A runaway greenhouse effect is an example of
a positive feedback mechanism
All else being equal, water will flow faster in a stream with ______ and a ______ wetted perimeter
a straight channel; small
Which type of coastline would most likely contain estuaries or fjords?
a submergent coastline
The amount of solar energy reflected by a surface is known as
albedo
The figure below shows a road in Death Valley, CA, curving around a(n)
alluvial fan
Major oceanic surface currents travel
at an angle to prevailing winds as a result of the Coriolis effect
The greenhouse effect is caused by
atmospheric gases, which trap heat radioed from Earth's surface
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
How are bicarbonate and carbon dioxide related to one another?
bicarbonate forms when Co2 molecules dissolve in water
Which of the following is NOT true? A 100-year flood _______
cannot occur in successive years
Which greenhouse gases play the most significant role in influencing changes in global atmospheric temperature?
carbon dioxide and methane
The hole in the ozone layer has been brought about by anthropogenic emissions of
chlorofluorocarbons
in the figure below, why is there a seasonal variation in carbon dioxide concentrations?
co2 concentrations rise and fall as photosynthesis decreases and increases
Thermohaline circulation carries _____ water from the poles to the equator, where the water becomes _______
cold; warm
braided streams
consist of a series of intertwined channels that are overloaded with sediment
The shallowest portions of ocean found along the margins of continents are the ____________.
continental shelves
Which portion of the seafloor is most steeply sloped?
continental slopes
The outer edge of a meander, where material is being eroded, is a(n) ________.
cut bank
Cycles of sea level rise and fall often create sandstone at the base, grade up into coal, and are called
cyclothems
Most individual nations have intentionally decreased their production and use of refrigerants and other chlorofluorocarbons in the last 20 yrs to address the _______
decrease in atmospheric ozone over the antarctic
The density of seawater increases with ________ in temperature and ________ in salinity.
decreasing; increasing
Compared with the Continental crust, the oceanic crust is _____
denser
Which of the following represents a unidirectional change in the nature of the earth?
differentiation of the layers of Earth
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
Which type of global change is reversible?
flooding of the continents because of global warming
The flat-lying area surrounding a river channel is termed the
floodplain
Longshore currents _____ the shoreline
flow parallel to
Pirate streams
form when headward erosion causes one stream to intersect another
The slope of a stream surface measured between two points along its course is the ________.
gradient
A small mountain stream will have a ________ competence and a ________ capacity than the Mississippi River.
greater; lower
Because of wave refraction, erosion along an irregular coastline is ________.
greatest along headlands
Which greenhouse gas has the greatest total importance in retaining radiant energy from Earth?
h2o
Meandering streams
have a channel that is highly sinuous (curvy)
Ephemeral streams
have flowing water either episodically or during a portion of the year
As more ice in the arctic ocean melts, what effect does this have on the water?
heat absorption increase as the albedo decreases
High tide will be ________ during a full moon than normally.
higher
The base level of a tributary would become ________ if a dam and a reservoir were constructed where it flowed into a trunk stream.
higher
The region below a streamed where groundwater flows in the same direction as the stream but at a slower rate is termed the ______ zone
hyporheic
The deepest segments of the ocean floor are found
in trenches associated with subduction zones
A blogger writes that global warming is not real, noting that his or her city had its coldest ever-recorded temperature last winter. The correct statement would be that the blogger is
incorrect, because global warming is measured only during the summer
The discharge of a river traveling through a temperate region will typically _____ downstream; the discharge of a river traveling through an arid region will typically ______ downstream
increase; decrease
The primary cause of recent global warming is believed to be
increased burning of fossil fuels
Along beaches, groins have
increased erosion rates immediately down current from the groin
The stream gradient of most rivers ______
is greater near the source than near the mouth
You have been given the extraordinary opportunity to take Alvin (a submersible) down into the Atlantic Ocean to examine how the seafloor sediments have changed throughout geologic history. You can use Alvin in only one location, however. Where do you pick to visit to get the ms=ost out of your trip inside Alvin?
just off the coast of North America
Moving away from its headwaters/source, the flow of a stream usually becomes more _______.
laminar
Which of these is the longest-lasting sink for carbon dioxide?
limestones
The sea surface salinity is ____ at the mouth of the Amazon river and ____ in the Dead Sea
low; high
V-shaped stream valleys result from the downcutting of stream erosion and ________.
mass wasting on the valley sides
Oxygen-18 and oxygen-16 are useful in studying past climates because _______
more oxygen-18 is tired in glacial ice when temperatures drop
Salone ocean water is ______ dense than fresh water and provides ______ buoyancy to objects floating in it.
more; more
At the equatorial ocean basins, the sea surface temps may reach 25.c of greater. What is the range of temps for the seafloor, approximately 4-5 km below?
near freezing (1.c-2.c)
Within a meander, where is sediment most likely to be deposited?
on the inner banks of the meander
A wave will disturb the water to a depth equal to ____________.
one-half of its wavelength
Milankovitch cycles describe variation in Earth's
orbit and tilt
A meander that is cut off to become completely 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 ratio of oxygen-16 and oxygen-18 isotopes in plankton fossils in deep-sea sediments can be used to determine _______.
past temperatures
With time, a river may erode terrain to produce a low-lying plain that lies close to the base level, which is termed a(n) ________.
peneplain
The inner edge of a meander, where sediment is deposited, is a(n) ____________.
point bar
The figure below is an aerial photograph of a meandering stream. The light-colored features labeled with arrows, below are ______
point bars
In the last few decades, global warming has been most strongly affecting the climate and wildlife of ____________ regions.
polar
Along a large cone-shaped volcano, a ________ drainage network is expected.
radial
In a region with prominent orthogonal sets of joints, a _____ drainage network is expected
rectangular
Waves
refract so as to impact the shore in a near parallel manner
A "bird's foot" delta configuration, similar to that of the Mississippi River delta, forms when the
river current exceeds the oceanic current
Ultimately, the base level of a stream valley can be no lower than
sea level
All else being equal, water will flow faster in a stream. that has a ____, which is typically found near the river's ______.
steep stream gradient; source
The deepest part of a curved stream channel, where the flow is fastest, is called the _____
thalweg
The distinction between a valley and a canyon is
that the sides of a canyon are more steep than those of a valley
Which modern sea do geologist believe might have filled very rapidly with ocean water when rising sea levels overtopped a small land bridge or a natural dam?
the Black Sea
The hydrologic cycle includes which of these?
the advance and retreat of glaciers
Sedimentary sequences, which are bounded by unconformities, record global sea level rise and fall with variations in
the coarseness of clastic sediments/sedimentary rocks
Barrier islands are constantly moving in the direction of
the longshore drift
Which of the following would be an area of the ocean with the least dense water?
the mouth of the Amazon River
Geological evidence suggests that many millions of years ago, the Amazon basin drained toward the west rather than the east. What caused this drained reversal?
the rise of the Andes Mountains
At a river delta, which of the following is NOT true?
the stream channel becomes very straight because of the large sediment load
Compared with the continental lithosphere, the oceanic lithosphere is
thinner
A biogeochemical cycle refers to the
transitioning and the residence of specific chemicals among living nonliving systems
In a region characterized by a parallel series of ridges and valleys, a _____ drainage network is expected.
trellis
The total sediment load of a stream consists of all of following EXCEPT the _____ load
turbulent
The castle on the island of Mont Saint-Michel, France, can be accessed ______ a day during ______ tide, but ______ during neap tide
twice; low; never
the presence of liquid water on earth's surface is
unique in the solar system; liquid water would not have developed had earth born much closer to or much farther from the sun
Which geologic event is NOT suspected as a source of major climate change and mass-extinction events?
very large earthquakes
Which of the following processes releases carbon dioxide into the atmosphere?
volcanism
During most of the Mesozoic Era, Earth was ____________.
warmer than present
With the increased data collected in recent years, scientist have become increasingly certain that the Earth's climate is ______
warming as a result of human inputs of atmospheric gases
Increasing ratios of oxygen-18 to oxygen- 16 in glacial ice indicate
warming temperatures
If a beach is in an east-west orientation and the waves are approaching the shore from a southeasterly direction, in which direction will the longshore drift be?
western
The shape of a delta is primarily determined by
whether river currents, wave-driven currents, or tidal currents are locally predominant