Geology Final
Which letters represent the wave height and wavelength?
E and B
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
Most of the ocean floor is made up of...
abyssal plains
What is the name of this rock type?
conglomerate
The mineral assemblage within metamorphic rock is...
dependent on both the mineral content of its protolith and the temperature and pressure of formation
The density of rocks is generally related to composition. What is the rock composition in order of increasing density?
felsic, intermediate, mafic, ultramafic
The stream gradient of most rivers...
is greater near the source than near the mouth
Continental lithosphere...
is thicker than oceanic lithosphere
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
The sea surface salinity is ... at the mouth of the Amazon River and ... in the Dead Sea
low; high
Waves...
refract so as to impact the shore in a nearly parallel manner
what is NOT considered sediments?
salt wedging
If sea level continues to rise and covers the city of Miami, the Florida coast will become a(n)...
submergent coast
What is the percentage of dissolved salt in seawater?
3.5%
The circumference of Earth is most nearly...
40,000km
Approximately what percentage of Earth's surface is covered with water?
70%
Assuming all other factors are equal, stream ... will have the fastest flow because of the difference in...
A; wetted perimeter
What 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
What river has the greatest discharge of any stream on Earth?
Amazon
Which letters represent the crest and trough?
C and D
What is your professors name in this class?
Harris
The boundary between the crust and the mantle is marked by an abrupt change in seismic velocity called the...
Moho
The deepest part of a curved stream channel, where the flow is fastest, is called the...
Thalweg
The band of earthquakes that follows the shape of the downgoing plate is termed the...
Wadati-Benioff zone
All else being equal, water will flow faster in a stream with ... and a ... wetted perimeter
a straight channel; small
What part of the deep-ocean floor is flat and nearly featureless?
abyssal plain
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 seal level
During a journey to the center to the Earth, one would experience temperature...
and pressure both increasing
Igneous rocks...
are formed through the freezing and 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
Evidence of paleomagnetism can be found in...
basalt, sedimentary rocks, any rock with magnetic minerals present
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 gasses...
becoming less dense
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
What is NOT true about a 100-year flood?
cannot occur in successive years
Broadly, metamorphism involves...
changes in mineralogy and texture in response to heat and stress
Lithified detritus (breakdown products of preexisting rocks) forms what kind of sedimentary rock?
clastic
As compared to aphanitic igneous rocks, phaneritic rocks are...
coarser grained
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 the continents are the...
continental shelves
What basic type of plate boundary is shown in the image?
convergent
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
Here, the distinct internal laminations are inclined at an angle to the boundary of the main sedimentary layers. This is termed..
cross beds
From left to right, correctly label each section of this slice of earth. Note that 1 starts at the surface of the Earth and 6 ends at the center of the Earth.
crust, upper mantle, transition zone, lower mantle, liquid outer core, solid inner core
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
Why does differential weathering occur?
different materials 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
What type of igneous intrusion is the vertical rock unit shown by letter A?
dike
What basic type of plate boundary is shown in the image?
divergent
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
What type of magma has the greatest silica content?
felsic
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
What is NOT true about 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 highly 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
Why is the surface salinity in the tropics so much higher than that of the equator or high latitudes?
higher evaporation rate and a lower rate of precipitation in the tropics
Mid-ocean ridges (MOR's), 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 higher than the surrounding crust
How water reacting with the crust is the basis for what type of metamorphism?
hydrothermal
What 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)...
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 dynamothermal metamorphism
The Moho...
is found deeper underneath continents than under oceans
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
Moving away from its headwaters/source, the flow of a stream usually becomes more...
laminar
What commonly serves as a protolith in the formation of marble?
limestone
Compaction and cementation of grains occurs during...
lithification
The difference between magma and lava is...
magma is found beneath the surface, whereas lava is found below the surface
If you were using both a compass and a map marked with latitude and longitude to navigate you might note that 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...
mas wasting on the valleys 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
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 25C or greater. What is the range of temperatures for the seafloor, approximately 4-5km 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 of 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
What 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
What is NOT a mineral?
petroleum
Bowen's continuous reaction series describes the crystallization behavior of what single mineral (with variable chemical composition)?
plagioclase
The inner edge of a meander, where sediment is deposited, is a(n)...
point bar
The light-colored features labeled with arrows 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
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 "birds foot" delta configuration, similar to that of the Mississippi River delta, forms when the...
river current exceeds the oceanic current
What 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
Marine magnetic anomaly belts are widest when and where?
seafloor spreading rates are relatively rapid
The majority of the rocks that occur at the surface of the Earth are...
sedimentary rocks
What commonly serves as a protolith in the formation of slate?
shale
Which describes the progression of rock types through INCREASING metamorphic grade?
shale, slate, phyllite, schist
Potassium feldspar (KA1Si3O8) is in which mineral class?
silicates
The most common minerals within Earth are...
silicates
What type of igneous intrusion is the horizontal rock unit shown by letter A?
sill
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
Death Valley is currently sinking partly due to the weight of continuously accumulating sediment shed from the mountains that boarder the valley. What phenomenon is this an example of and what depositional environment is created by the sediment deposition?
subsidence and alluvial fans
As compared with metamorphism, diagensis...
takes place at lower temperatures and pressures
What river is a threat to capture the flow of the Mississippi River through avulsion and stream piracy?
the Atchafalaya River
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?
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 suing this sediment?
the silt will be washed away by the waves, leaving the beach no better off
At a river delta, what 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
What will eventually happen to the headlands in the figure?
they will become a straight line of cliffs as rock is eroded away
Compared to oceanic crust, continental crust is...
thicker
Compared with the continental lithosphere, the oceanic lithosphere is...
thinner
What type of basic plate boundary is shown?
transform
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 suspended, bed, dissolved load, EXCEPT...
turbulent
What is the list of compositions in order of increasing silica content?
ultramafic, mafic, intermediate, felsic
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 10C warmer than they had been. Why did this happen?
warm Caribbean Sea waters were forced up into the north Atlantic Ocean
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