2
What is the percentage of dissolved salt in seawater?
3.5%
The circumference of Earth is most nearly ________.
40,000 km
Approximately what percentage of Earth's surface is covered with water?
70%
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
Using the figure below, which of the following lists correctly identifies the various seafloor landforms?
A=continental shelf, B=continental slope, D=continental rise, G=abyssal plain, C=mid-ocean ridge, F=trench, and E=volcanic arc
Evidence of paleomagnetism can be found in ________.
ALL -basalt that has cooled from lava -sedimentary rocks where minerals from ion-bearing groundwater -any rock with magnetic minerals present
Which river has the greatest discharge of any stream on Earth?
Amazon
seafloor spreading rates are relatively rapid
Consult the figure below. Marine magnetic anomaly belts are widest when and where ________.
crust, upper mantle, transition zone, lower mantle, liquid outer core, solid inner core
From left to right, correctly label each section of this slice of the Earth. Note that 1 starts at the surface of the Earth and 6 ends at the center of the Earth.
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, thus the new crust will sit nighter than the surrounding crust
C and D
In the figure below, which letters represent the crest and trough?
E and B
In the figure below, which letters represent the wave height and wavelength?
sill
In the figure provided below, what type of igneous intrusion is the horizontal rock unit shown by letter A?
The deepest part of a curved stream channel, where the flow is fastest, is called the ________.
Thalweg
Which river is a threat to capture the flow of the Mississippi River through avulsion and stream piracy?
The Zydeco River
dendritic
The figure below shows an example of a ________ drainage network.
radial
The figure below shows an example of a ________ drainage network.
rectangular
The figure below shows an example of a ________ drainage network.
trellis
The figure below shows an example of a ________ drainage network.
wadati-benioff zone
The image below shows a cross-sectional view of a typical subduction zone, with earthquake locations shown with small dots. The band of earthquakes that follows the shape of the downgoing plate is termed the ________.
Why is the surface salinity in the tropics so much higher than that of the equator or high latitudes?
There is a higher evaporation rate + a lower rate of precipitation in the tropics
Scientists 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 forces up into the North Atlantic ocean
They will become a straight line of cliffs as rock is eroded away
What will eventually happen to the headlands in the figure below?
convergent
Which basic type of plate boundary is shown in the image below?
divergent
Which basic type of plate boundary is shown in the image below?
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
All else being equal, water will flow faster in a stream with ________ and a ________ wetted perimeter.
a straight channel; small
Which of these parts of the deep-ocean floor is flat and nearly featureless?
abyssal plain
Most of the ocean floor is made up of ________.
abyssal plains (4 to 5 km below sea level)
The figure below shows a road in Death Valley, California, curving around a(n) ________.
alluvial fan
The youngest sea floor is typically found ________.
along mid-ocean ridges
A guyot is ________.
an extinct oceanic hot-spot volcano that has subsided below sea level
During a journey to the center of the Earth, one would experience temperature ________.
and pressure both increasing
Igneous rocks ________.
are formed thru the freezing or crystallization of a melt
A clastic rock composed of sand-sized grains derived from the physical weathering of granite and containing a sizable proportion of feldspar is termed ________.
arkose
The lithosphere lies directly above the ________.
asthenosphere
Major oceanic surface currents travel ________.
at an angle to prevailing winds as a result of the Coriolis effect
Precambrian metamorphic rocks are exposed at the surface ________.
at places in continental interiors termed shields
Beneath a blanket of sediments, oceanic crust is primarily composed of ________.
basalt
The form and topography (depth profile) of the ocean floor is termed ________.
bathymetry
Which environment would most likely produce sedimentary deposits characterized by very well-sorted, very well-rounded grains that are nearly pure quartz?
beach
Why is a spring tide so much higher than a normal high tide?
because the sun is aligned with the moon
If one were to ride a hot air balloon up into the atmosphere, one would experience the concentration of gases ________.
becoming less dense
133. Geologists call individual layers of sedimentary rocks ________, whereas several of them together are called ________.
beds; strata
Cemented shells of marine organisms form which kind of sedimentary rock?
biochemical
The rapid, deep burial of sediments in an accretionary prism leads to the formation of a metamorphic rock termed ________.
blueschist
Which of the following is NOT true? A 100-year flood ________.
cannot occur in successive years
Which of the following are NOT considered sediments?
cemented grains
Broadly, metamorphism involves ________.
changes in mineralogy and texture in response to heat and stress
Lithified detritus (breakdown products of preexisting rocks) forms which kind of sedimentary rock?
clastic
As compared to aphanitic igneous rocks, phaneritic rocks are ________.
coarser grained
The image below shows an outcrop of coarse-grained sedimentary rock. Note the rock hammer for scale. What is the name of this rock type?
conglomerate
As compared to the rocks that make up the crust, Earth as a whole is ________.
considerably more dense
Braided streams ________.
consist of a series of intertwined channels that are overloaded with sediment
The shallowest portions of an ocean found along the margins of continents are the ________.
continental shelves
As compared to the asthenosphere, the lithosphere is ________.
cooler and less able to flow
Of the three primary compositional layers of the Earth (crust, mantle, core), which is the thickest layer?
core
Consult the figure below. Here, distinct internal laminations are inclined at an angle to the boundary of the main sedimentary layers. This is termed ________.
cross beds
In the formation of gneiss from granite, distinctive compositional bands form because of ________.
crystals dissolving, with atoms and ions migrating and reorganizing as new crystals
The outer edge of a meander, where material is being eroded, is a(n) ________.
cut bank
The density of seawater increases with ________ temperature and ________ salinity.
decreasing; increasing
Compared with the continental crust, the oceanic crust is ________.
denser
The mineral assemblage within metamorphic rock is ________.
dependent on both the mineral content of its protolith and the temperature and pressure of formation
Why does differential weathering occur?
different minerals have different resistances to weathering
The application of ________ during metamorphism causes elongated crystals to align parallel with each other. When this happens, the rock develops ________.
differential stress; foliation
The removal of detritus from weathered rock at an outcrop is termed ________.
erosion
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 magma has the greatest silica content?
felsic
The density of rocks is generally related to composition. Which of the following choices places rock compositions in order of increasing density?
felsic, intermediate, magic, ultramafic
The flat-lying area surrounding a river channel is termed the ________.
floodplain
Rip currents ________ the shoreline.
flow directly away from
Longshore currents ________ the shoreline.
flow parallel to
Slaty cleavage, schistosity, and compositional banding are all examples of ________.
foliation
Which of the following statements is NOT true? Hornfels facies ________.
form at high pressures but low temperatures
Pirate streams ________.
form when headward erosion causes one stream to intersect another
As compared to ultramafic rocks, mafic rocks have a ________.
greater proportion of silica
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
meandering streams ____.
have a channel that is high sinuous (curvy)
Ephemeral streams ________.
have flowing water either episodically or during only a portion of the year
High tide will be ________ during a full moon than normally.
higher
Consult the figure below. Hot water reacting with the crust is the basis for what type of metamorphism?
hydrothermal
Which transport medium carries the largest particles?
ice in glaciers
Thermal (contact) metamorphism occurs ________.
in areas surrounding igneous intrusions
The deepest segments of the ocean floor are found ________.
in trenches associated with subduction zones
All other factors equal, if a body of magma becomes more felsic, its viscosity will ________.
increase
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
Along beaches, groins have ________.
increased erosion rates immediately down current from the groin
With increasing distance from a mid-ocean ridge, the age of oceanic crust ________.
increases
A mineral within a metamorphic rock that can be used to provide a narrow constraint on the temperature and pressure of rock formation is termed a(n) ________ mineral.
index
The densest layer of Earth is the ________.
inner core
Chemical weathering involves the breakdown of material due to ________.
interaction with water or air
Unlike the lithosphere, the asthenosphere ________.
is able to flow over long periods of time
At a subduction zone, the downgoing (subducting) plate ________.
is always composed of oceanic lithosphere
Regional metamorphism ________.
is another name for dynamo thermal metamorphism
The Moho ________.
is found deeper underneath continents than under oceans
The stream gradient of most rivers ________.
is greater near the source than near the mouth
Continental lithosphere ________.
is thicker than oceanic lithosphere
The entire state of Florida is composed of fossiliferous limestone, what does this imply about Florida during the recent past?
it was submerging 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
Moving away from its headwaters/source, the flow of a stream usually becomes more ________.
laminar
________ commonly serves as a protolith in the formation of marble.
limestone
Compaction and cementation of grains occurs during ________.
lithification
The sea surface salinity is ________ at the mouth of the Amazon River and ________ in the Dead Sea.
low; high
The difference between magma and lava is ________.
magma is found beneath the surface, whereas lava is found at the surface
If you were using both a compass and a map marked with latitude and longitude to navigate, you might note the angle difference between your compass and what is marked on the map, called ________.
magnetic declination
Marine magnetic anomalies result from seafloor spreading in conjunction with ________.
magnetic polarity reversals
Where Earth's magnetic dipole intersects with the surface of the planet is called the ________.
magnetic pole
V-shaped stream valleys result from the downcutting of stream erosion and ________.
mass wasting on the valley sides
What is a primary difference between phyllite and schist?
mica crystals within schist are larger than those within phyllite
Dissolution occurs when ________.
minerals are dissolved into water
Bioturbation is the ________.
mixing of sediment by burrowing organisms
The boundary between the crust and the mantle is marked by an abrupt change in seismic velocity called the ________.
moho
Saline ocean water is ________ dense than fresh water and provides ________ buoyancy to objects floating in it.
more; more
The sedimentary rocks breccia and conglomerate most commonly form in a ________ environment.
mountain stream
At the equatorial ocean basins, the sea surface temperatures may reach 25°C or greater. What is the range of temperatures for the seafloor, approximately 45 km below?
near freezing (1C-2C)
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
Eratosthenes was the first person to accurately estimate the size of Earth. He accomplished this feat by ________.
observing shadows simultaneously cast at two different cities that were separated by a known distance
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
A wave will disturb the water to a depth equal to ________.
one-half its wavelength
Two major sources of energy, coal and oil shale, are considered ________ sedimentary rocks.
organic
A meander that is cut off to become completely isolated from the main channel but which retains water is a(n) ________.
oxbow lake
Which type of weathering process is happening to materials when they rust?
oxidation
Along a uniform and steep slope of relatively weak substrate, a ________ drainage network is expected.
parallel
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
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 place your groin?
perpendicular to the shore to the east of your house
Which of the following is NOT a mineral?
petroleum
Bowen's continuous reaction series describes the crystallization behavior of which single mineral (with variable chemical composition)?
plagioclase
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
The process of low-grade metamorphic rocks being altered to form high-grade metamorphic rocks is termed ________ metamorphism.
prograde
Preexisting rock that is subsequently altered to form a metamorphic rock is termed a ________.
protolith
Waves ________.
refract so as to impact the shore in a nearly parallel manner
The process of high-grade metamorphic rocks being altered to form low-grade metamorphic rocks is termed ________ metamorphism.
retrograde
A well-sorted sandstone with asymmetric ripples was most likely deposited as sand by a ________.
river (far from source)
A "bird's foot" delta configuration, similar to that of the Mississippi River delta, forms when the ________.
river current exceeds the oceanic current
What type of weathering are you most likely to find occurring on the coast?
salt wedging
________ commonly serves as a protolith in the formation of quartzite.
sandstone
Ultimately, the base level of a stream valley can be no lower than ________.
sea level
The majority of the rocks that occur at the surface of Earth are ________.
sedimentary rocks
________ commonly serves as a protolith in the formation of slate.
shale
Which of the following describes the progression of rock types through increasing metamorphic grade?
shale, slate, phyllite, schist
Potassium feldspar (KAlSi3O8) is in which mineral class?
silicates
The most common minerals within Earth are ________.
silicates
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
If sea level continues to rise and covers the city of Miami, the Florida coast will become a(n) ________.
submergent coast
Death Valley is currently sinking partly due to the weight of continuously accumulating sediment shed from the mountains that border the valley. What phenomenon is this an example of and what depositional environment is created by the sediment deposition?
subsidence + alluvial fans
As compared with metamorphism, diagenesis ________.
takes place at lower temperatures and pressures
Oceanic lithosphere thickens away from the mid-ocean ridge primarily due to ________.
the addition of new lithospheric mantle as a result of cooling
Stratification refers to ________.
the development of layering within sedimentary rocks
Barrier islands are constantly moving in the direction of ________.
the longshore drift
Geological evidence suggests that many millions of years ago, the Amazon basin drained toward the west rather than the east. What caused this drainage reversal?
the rise of the Andes Mountains
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 silt will be washed away by the waves, leaving the beach no better off
At a river delta, which of the following is NOT true?
the stream channel becomes very straight because of the large sediment load
According to Archimedes' principle of buoyancy, an iceberg sinks until ________.
the total mass of the water displaced equals the total mass of the whole iceberg
Compared to oceanic crust, continental crust is ________.
thicker
Compared with the continental lithosphere, the oceanic lithosphere is ________.
thinner
Sea level rises locally, and marine sediments are deposited on top of terrestrial sediments during events termed ________.
transgressions
Chemically precipitated limestone that forms in caves or around hot springs is termed ________.
travertine
The atmosphere is divided into several distinct layers. Beginning with the layer in which we live, they are, in order, ________.
troposphere, stratosphere, mesosphere, and thermosphere
The primary stream fed by tributaries within a dendritic drainage network is termed a ________ stream.
trunk
When graded beds are observed in a rock outcrop, this tells geologists that a ________.
turbidity current deposited these beds, depositing coarser material first
The total sediment load of a stream consists of all of following EXCEPT the ________ load.
turbulent
Which of the following lists compositions in order of increasing silica content?
ultramafic, mafic, intermediate, felsic
If a geologist found preserved mud cracks, he or she could conclude that the environment in which they formed ________.
was once covered in wet mud
Retrograde metamorphism will not occur unless an increased amount of ________ is added to the system.
water
Potassium feldspar reacts with water to form clay. This is an example of ________.
weathering
The breakdown of exposed rock into small fragments and dissolved ions is termed ________.
weathering
The shape of a delta is primarily determined by ________.
whether river currents, wave-driven currents, or tidal currents are locally predominant
