Shared Flashcard Set

Details

Test Q&A for UGA A.Patino-Douc
Q&A for tests I,II, and III
180
Geology
Undergraduate 1
05/03/2006
Click here to study/print these flashcards.

Create your own flash cards! Sign up here.

Additional Geology Flashcards

 

 

Cards

Term
The distinction between the lithosphere and asthenosphere is:
 Definition
The asthenosphere is weak and plastic-like while the lithosphere is strong and rigid.
Term
The most abundant element in the universe is:
 Definition
hydrogen
Term
If the half life of a radioactive parent isotope is 1.5 million years, and a rock has 12.5% remaining parent and 87.5% daughter, then the ago of the rock is:
 Definition
4.5 Ma
Term
A clastic sedimentary rock contains grains of the mineral feldspar that have an age of 440 Ma. The sedimentary rock is cut by two igneous dikes, one of them has an age of 396 Ma and the other one an age of 68 Ma. Which of the following is possible ages fo
 Definition
410 Ma
Term
The earliest life forms on earth likely to have been:
 Definition
heat-loving prokaryotes
Term
The earliest evidence for life on Earth dates from:
 Definition
3.8 billion years ago
Term
Which of these physical features would most liely be present in a plutonic (or intrusive) rock:
 Definition
course-grained texture
Term
Lava and tephra are:
 Definition
two different ways in which magmas can be erupted
Term
A volcanic rock with about 50% SiO2 is called a :
 Definition
basalt
Term
An important difference between the Solar nebula and the clouds of gas from which generation stars formed is that:
 Definition
the solar nebula contained all of the elements in the periodic table, whereas first generation stars formed from clouds of pure hydrogen and helium.
Term
The compositions of which of these objects tells us about the composition of the Solar Nebula:
 Definition
chondritic meteorites
Term
What is the approximate age (in years) of the oldest rocks round on Earth so far:
 Definition
4 billion
Term
What is the threat from the collapse of volcanic islands in the oceans:
 Definition
it will trigger enormous tsunamis
Term
The reason why silicate minerals are the most abundant rock-forming minerals is that:
 Definition
silicon and oxygen are the main constituents of the earth’s crust and mantle
Term
The elements formed during the Big Bang are:
 Definition
hydrogen and helium
Term
A scientific theory must be successful in doing which of the following:
 Definition
explain observations and predict new observations
Term
The age of the earth is:
 Definition
4.55 billion years
Term
A plutonic rock with 70% SiO2 is a :
 Definition
granite
Term
Why is fresh water a critical natural resource?
 Definition
because food production relies heavily on irrigation and because humans extract groundwater and river water faster than it is replenished
Term
Why do we know that when the moon formed the earth already had diffentiated into a core and mantle:
 Definition
because the moon has only 6% iron
Term
Approximately how much will sea level rise if all glaciers on Earth were to melt:
 Definition
300ft
Term
Which of the following are likely outcomes of a cataclysmic eruption of Yellowstone volcano:
 Definition
a large area of land will be covered in ash and global temperatures will drop
Term
Chemical sediments are formed by:
 Definition
precipitation of minerals from a solution
Term
According to the principle of superposition:
 Definition
the rocks at the bottom of a layered succession are the oldest
Term
What is a requirement for earth-like life:
 Definition
photosynthesis and salty oceans are required
Term
Which of the following is true about lava flows an pyroclastic eruptions:
 Definition
they are different ways in which magma can reach the earth’s surface
Term
Which of the following is not part of a magma:
 Definition
hot ash
Term
Successful predictions of the theory of evolution include:
 Definition
the humans and chimpanzees must have very similar DNA
Term
Which of the following processes is involved in the formation of the clastic sedimentary rock:
 Definition
weathering and erosion
Term
The earth is a differentiated planetary body because:
 Definition
it is made up of concentric layers of different composition
Term
Which of the following is a consequence of the fact that the basic building block of silicate minerals, the SiO4 tetrahedron, can polymerize to form complex molecules:
 Definition
there is a wide variety of silicate minerals
Term
The earliest life-forms on earth:
 Definition
probably arose from volcanic vents and metabolized by fermentation
Term
In order for a naturally occurring substance to be called a mineral it must have:
 Definition
crystalline structure
Term
Which of the following statements is true about the density of the earth’s mantle and crust:
 Definition
the earth as a whole is denser than the mantle and crust and the density relationship proves tha the earth is a differentiated planet
Term
Clastic sedimentary rocks are primarily classified accoreing to their:
 Definition
grain size
Term
A substance is said to be a crystalline solid if:
 Definition
it has a microscopic structure characterized by a regular and periodic arrangement of atoms
Term
Which earth subdivision has the highest density:
 Definition
core
Term
The half life of radioactive isotopes:
 Definition
is constant and characteristic of each isotope
Term
What is the approximate age of the universe:
 Definition
13 billion years
Term
The relationship between the composition of chondritic meteorites, the earth’s mantle and the earth’s core is the following:
 Definition
chondritic meteorites have more Fe than the mantle, so the core must have more Fe than the mantle
Term
The earth’s mantle is composed chiefly of:
 Definition
silicon and magnesium
Term
Rocks with porphyritic texture indicate:
 Definition
two stages of cooling at different rates
Term
Which of the following observations is used to estimate age of the universe:
 Definition
distance to galaxies and velocity with which galaxies are moving apart
Term
Separation of the core from the mantle took place:
 Definition
more than 4 ga, shortly after formation of the earth and as a consequence of a large impact that melted almost all the earth
Term
Why is melting of snow an dice on Mt. Kilimanjaro and other tropical glaciers an alarming occurrence:
 Definition
because it indicates that the earth’s atmosphere is warming at a very fast rate
Term
Which phenomenon is fueled by earth’s internal heat:
 Definition
volcanos
Term
Which of the following statements is true:
 Definition
the moon is more heavily cratered than the earth because the earth’s surface is constantly renewed by plate tectonics
Term
The types of fossils present in sedimentary rocks allows us to do which of the following:
 Definition
determine whether or not two geographically distant rock outcrops are of the same age
Term
Which of the following is not a terrestrial planet
 Definition
Uranus, Jupiter, Saturn, Pluto, Neptune; only Mercury, Earth, Venus, Mars, and the moon are terrestrial
Term
The chief criterion used to classify igneous rocks according to their compositions is:
 Definition
how much silica they contain
Term
Which of the following is threats to the survival of the human species:
 Definition
overpopulation and overconsumption of natural resources
Term
What is an iron meteorite:
 Definition
a fragment of the core of a differentiated planet that was shattered by a large collision
Term
The origin of the oxygen in the earth’s atmosphere is:
 Definition
photosynthesis
Term
What is the approximate difference between the time scale for oil formation and the time scale over which humans have used up half of the world’s oil supply:
 Definition
tens of millions of years vs. 150 years
Term
What is lahar:
 Definition
a mud flow triggered by a volcanic eruption
Term
What is the relationship between burning of fossil fuels and global warming:
 Definition
burning fossil fuels increase atmospheric CO2, which traps heat in the earth’s atmosphere
Term
Which of these elements must be the product of a supernova:
 Definition
silver (any elements past Fe on the periodic table, because Fe is the heaviest produced by stars before they go supernova)
Term
The core of the earth is composed of:
 Definition
predominantly Fe
Term
Which of the following is not part of the process responsible for the origin of metamorphic rocks:
 Definition
????
Term
The first complex organic molecules on earth:
 Definition
were produced by spontaneous combination of simple inorganic molecules (CO2, H2, or H2O.
Term
The best example of a modern Continental Rift is:
 Definition
The East African Rift Valley
Term
Why is the distribution of coal beds in North America and Europe important to the argument that supports continental drift:
 Definition
Because Wegner’s reconstruction of the shape and location of Pangaea places the coal beds near the equator.
Term
What is a lahar:
 Definition
a mudflow triggered by a volcanic eruption
Term
Why do earthquakes at transform plate margins tend to be more destructive than other earthquakes:
 Definition
Because they are shallower than other earthquakes and Because rocks are stronger when subjected to sheer stress
Term
Which of the fallowing provides the basis to calculate the location of an earthquake’s epicenter:
 Definition
the fact that P waves always travel faster than S waves
Term
Continental crust is as old as ____ million years, where as oceanic crust is always younger than ___ million years.
 Definition
4000; 200
Term
Why is there basaltic volcanism in continental rifts:
 Definition
because rifts are underlain by hot molten mantle, associated to continental break up
Term
Which of the fallowing statements about plate tectonics is true:
 Definition
most tectonic plates contain continents and ocean floor
Term
What is soil liquefacation:
 Definition
The softening of the ground during an earthquake, caused by water being squeezed out by shaking and soil particle shifting
Term
The Pacific Northwest is considered to be at risk of suffering a major earthquake because:
 Definition
The area corresponds to a convergent plate margin and There have been no major earthquakes in recent history, implying that elastic energy is building up in the rocks
Term
Which of the fallowing is most important in determining if an eruption is from a shield volcano:
 Definition
the viscosity of the magma
Term
Why was the discovery of stripes of normal and reverse magnetization on the ocean floor a clinching argument in support of sea-floor spreading:
 Definition
Because they prove that the sea floor forms along mid-ocean ridges and moves away from them
Term
Major differences between the a volcanic island arcs, such as the Aleothens, and a chain of oceanic islands, such as the Hawaiian Islands, include:
 Definition
Ages of volcanic centers are more or less the same along an island arc, but become progressively younger towards one end of a chain of oceanic islands
Term
Which of the fallowing is true about volcanic Calderas:
 Definition
Larger calderas form during catastrophic pyroclastic eruptions
Term
The shadow zone for S waves indicates that:
 Definition
part of the core is molten.
Term
There is no active magmatic arc in the Himalayas because:
 Definition
no subduction is taking place at the present
Term
Magmas at subduction zones are formed at the point where the top of the subducting plate is approximately ____ km deep.
 Definition
150
Term
The focusing of P waves in regions of the Earth directly opposite from an earthquake indicates that:
 Definition
the inner core is solid
Term
Which of the fallowing is true about the Earth’s magnetic field:
 Definition
It arises from convection in the molten metal outer core and It has reversed (“flip-flopped”) many times in Earth’s history.
Term
Why are earthquakes stronger at convergent margins stronger than those at divergent margins:
 Definition
because rocks break more easily when being stretched than when being compressed
Term
What is the relationship between magnitude and frequency of an earthquake:
 Definition
Weak earthquakes are much more frequent than strong earthquakes
Term
How was it discovered that earth’s magnetic field has undergone many reversals during Earth’s history:
 Definition
By sampling thick piles of lava flow in large volcanoes, such as in Hawaii
Term
A magma with which of the fallowing statements about lava flows and pyroclastic eruptions is true:
 Definition
viscous and gas-rich magmas produce pyroclastic eruptions, where as low viscosity and gas-poor magmas erupt as lava flows
Term
A magma with which of the fallowing characteristics will be the most viscous:
 Definition
low temperature and low silica content
Term
In which of the fallowing places would you expect to find the oldest oceanic crust on Earth:
 Definition
Off the west coast of South America
Term
What are continental flood basalts:
 Definition
huge flows of basaltic lavas that are erupted along fractures in the Earth’s crust
Term
Which of the fallowing is an example of igneous activity in the interior of a plate (i.e. not associated to a plate margin):
 Definition
the Hawaiian Islands
Term
Why is fire a seismic hazard:
 Definition
because gas lines can break during an earthquake and because the power lines can snap during an earthquake
Term
The distance between a magmatic arc and the corresponding oceanic trench is determined by:
 Definition
the steepness at which the oceanic plate subducts
Term
The boundary between the crust and the mantle, or moho, is located on the basis of:
 Definition
a sudden increase in the velocity of seismic waves
Term
Why is the distribution of ancient glacial pavement in the southern continents a strong argument for continental drift:
 Definition
because it can only be experienced if the southern continents were joined in a single polar land mass
Term
Why is the Martian volcano Olympus Mons so much larger than any volcano on Earth:
 Definition
Because Mars has lower gravity than Earth and Because there are no plate tectonics on Mars.
Term
What was the most important line of argument against Wegner’s idea of continental drift:
 Definition
Wegner could not provide a physically viable driving mechanism for continental drift
Term
How do we know that the asthenosphere is not molten:
 Definition
Because if it was, then the shadow zone for S waves would be much wider than it is
Term
The Red Sea is:
 Definition
A baby ocean basin
Term
One difference between the theory of plate tectonics and continental drift as envisioned by Wegner is:
 Definition
According to plate techtonics lithosperic plates that contain both continents and oceans move as a whole by sliding over the asthenosphere, whereas Wgener thought that continents move by sliding across the ocean floor.
Term
Which of the following is (are) true about normal faults?
 Definition
They are found at divergent plate margins
Term
Is the Atlantic or the Pacific Ocean spreading faster, and how do we know?
 Definition
The Pacific, because stripes of ocean floor of the same age are wider than in the Atlantic.
Term
Why does Subduction not take place when a convergent plate margin involves two continental plates?
 Definition
Because the density of the continental crust is too low to allow it to be subducted.
Term
The difference between P and S seismic waves is that:
 Definition
P waves vibrate in the same direction as the wave propagates, and S waves vibrate in a direction perpendicular to that of wave propagation.
Term
What is the significance of Benioff’s zone?
 Definition
t uses the location of earthquakes to map the path of oceanic floor as it sinks back into the mantle and It shows that oceanic trenches are the place where the ocean floor bends in order to subduct.
Term
The long as narrow depression that borders the western continental margin of South America is an example of a (an):
 Definition
Oceanic trench
Term
Transform plate margins are characterized by:
 Definition
All of the above: strike-slip faults, shallow earthquakes, lack of magmatic activity, destructive earthquakes
Term
The arguments that Wegener used to support the concept of continental drify included:
 Definition
all of these: distribution of animal fossils, jigsaw-puzzle ‘fit’ of the continents, distribution of glacial sediments.
Term
What should be your main source of concern if you lived near a large shield volcano?
 Definition
Extensive lava flows causing property damage.
Term
The theory of isostasy explains the altitude of mountain ranges as a result of:
 Definition
thickness of the crust
Term
Why was Wegener’s idea of continental drift better received in the Southern Hemisphere that in the Northern Hemisphere?
 Definition
Because the fossil evidence for continental drift is better preserved in Southern Hemisphere continents.
Term
The Hawaiian islands are the result of:
 Definition
a mantle hot-spot
Term
Why are continents permanent features of the Earth, whereas oceans have limited life spans?
 Definition
Because ocean floor is able to subduct and continents are not.
Term
For each unit increase in the Richter magnitude of an Earthquake:
 Definition
Ground motion increases by 10.
Term
Which of the following is (are) true about air-fall tuffs and ash-flow tuffs?
 Definition
Air-fall tuffs form from ash that is injected into the stratrosphere and then rains down; Ash-flow tuffs form from clouds of ash and gas that move downhill hugging the ground.
Term
What was the significance of the fossil Mesosaurus to Wegener’s continental drift hypothesis?
 Definition
It is only found in a few localities in South America and South Africa.
Term
What is the central ideas of sea floor spreading that had eluded Wegener?
 Definition
That the ocean floor is not static, but is rather constantly forming by volcanism along mid-ocean ridges.
Term
The process of mantle convection:
 Definition
Causes upwelling of hot mantle under mid-ocean ridges.
Term
The next island in the Hawaiian chain should appear:
 Definition
southeast of Hawaii
Term
Which of the following is (are) true about composite cones?
 Definition
They are composed of alternating layers of lava flows and pyroclastic deposits, they are found at magmatic arcs along convergent plate margins.
Term
Away from mid-ocean ridges the oceanic crusts increases in:
 Definition
age
Term
Divergent plate margins are born at:
 Definition
continental rifts
Term
Shield volcanoes are primarily composed of:
 Definition
Basalt lava flows.
Term
Splitting of the super continent Pangea began:
 Definition
Along a continental rift.
Term
1.Which of the following is (are) part of the definition of a desert?
 Definition
Average rainfall less than 25 cm. per year;IT HAS NOTHING TO DO WITH TEMPERATURE! THERE ARE DESERTS IN SIBERIA!
Term
The Atlantic margin of North American is a passive continental margin because:
 Definition
it is not a plate margin
Term
What is the relationship between Milankovitch cycles and Pleistocene glaciations?
 Definition
Milankovitch cycles explain the timing of Pleistocene glaciations but the magnitude of the glaciations was greater that the cycles by themselves can explain.
Term
What is the term applied to a current that flows away from shore, across the surf zone?
 Definition
Rip current
Term
The landscape of a particular region is controlled by:
 Definition
all of the above: rock type, climate, time
Term
What is (are) differences between sand beaches and wave-cut platforms?
 Definition
Wave-cut platforms are erosional features, sand beaches are formed by depositional sediments.
Term
What does the term “fetch” refer to?
 Definition
distance that wind blows over open water.
Term
In order for a concentration of metallic minerals to be an ore deposit:
 Definition
It must be possible to extract the metal at a profit given current market conditions.
Term
Which of the following is (are) factors in the formation of coastal deserts?
 Definition
Cold ocean currents.
Term
During the Pleistocene, when glaciers covered most of Canada and the northern U.S., climate in the desert southwest was:
 Definition
Colder and wetter than today.
Term
The shape and orientation of sand dunes depends on:
 Definition
Whether or not there is a prevailing wind direction and How much sand is available.
Term
What is a glacial outwash?
 Definition
A stream that originates from beneath a glacier.
Term
What caused the large inland lakes in the Great Basin (e.g., Lake Bonneville, Lake Lahontan, Lake Manly) to dry up?
 Definition
Climate change at the end of the last glacial age.
Term
What is the lowest elevation towards which a river is flowing called?
 Definition
Base level
Term
What determines the size of ocean waves?
 Definition
Wind velocity and Length of time that wind blows and Distance that wind blows over open water.
Term
What is a bajada?
 Definition
An apron of coarse-grained sediment deposited at the foot of a mountain range, formed by overlapping alluvial fans.
Term
What does it mean that a flood is a 100 year flood?
 Definition
That a flood of that magnitude occurs on average every 100 years and That on any given year there is a 1% chance of a flood of that magnitude.
Term
Which of the following is not a desert of the American Southwest?
 Definition
New Mexican
Term
When freshwater is extracted from rivers, what category(ies) do(es) household water use fall into?
 Definition
Off-stream and Non-Consumptive
Term
What causes the bands of subtropical latitudinal deserts at about 30 degrees north and south of the Equator?
 Definition
Sinking of dry air that lost its humidity in tropical regions closer to the equator and Heating up of the air as it sinks towards the Earth’s surface.
Term
What is the discharge of a river or stream?
 Definition
The volume of water that the river carries per unit time.
Term
The chief erosional agent in deserts is:
 Definition
Water
Term
Which of the following is (are) erosional effects of waves on coastlines?
 Definition
They straighten up irregular coasts
Term
Which of the following could help stop desertification?
 Definition
hey are all terrible ideas: Irrigate crops so as to humidify the soil, Build cities in the desert, so that sand dunes are paved over, Build dams so that river water can be collected in lakes. THE ONLY SOLUTION IS HALTING POPULATION GROWTH.
Term
What is the main reason why the east and west coasts of the U.S. look so different?
 Definition
Because the west coast is an emergent coastline and the east coast is a submergent coastline.
Term
When did the large inland Pluvial lakes in the Great Basin begin to dry up?
 Definition
About 11,000 years ago.
Term
What is a playa?
 Definition
A flat area of a desert covered by very fine-grained sediments.
Term
What is desert pavement?
 Definition
An erosional feature produced by deflation;A mosaic of interlocking pebbles covering the desert floor.
Term
Wave-cut platforms and marine terraces:
 Definition
Are formed by wave action as emergent coasts and Are chiefly erosional (as opposed to depositional) features.
Term
Why did banded iron formations form only once in Earth’s history?
 Definition
Because they formed when oxygen first appeared in Earth’s atmosphere.
Term
Which of the following is NOT a factor in the Milankovitch cycle explanation for glacial periods?
 Definition
Changes in the Earth-Moon distance.....READ THROUGH THE NOTES FOR THE MILANKOVITCH CYCLE! THIS QUESTION IS LIKELY TO BE BACKWARD ON THE FINAL. KNOW WHAT THE FACTORS ARE!!!
Term
What is a marine terrace?
 Definition
An old wave-cut platform elevated above sea level.
Term
Which of the following is (are) NOT characteristic(s) of old age river systems?
 Definition
Flash floods and Steep gradient are not! know what is! these are in the other set of geology flashcards i made, and very detailed, so you should look at that.
Term
A rock glacier is:
 Definition
A moraine that creeps skidding on the surface of a frozen lake.
Term
What dies “water mining” mean?
 Definition
Extracting groundwater faster than it is recharged.
Term
Under what circumstances does a glacier flow downhill?
 Definition
When it is advancing, When it is retreating,When its size is not changing
Term
Glacial tributary valleys:
 Definition
are often occupied by waterfalls and are called hanging valleys
Term
How can you distinguish between a glacial valley and a river valley?
 Definition
Glacial valleys are U-shaped, whereas river valleys are V-shaped.
Term
What is a losing stream?
 Definition
A stream that contributes water to underlying aquifers.
Term
Which of the following is an arête?
 Definition
Narrow ridge between two glacial valleys.
Term
Where is most of the world’s freshwater located?
 Definition
Ice and snow
Term
What is land reclamation?
 Definition
Returning the land to its original state after the ore in a mine is exhausted.
Term
Which of the following is a lake formed by water filling in a glacial cirque?
 Definition
Tarn
Term
Which of the following is a weathering-type ore deposit?
 Definition
Bauxite (e.g., aluminum ore).
Term
What kind of desert is the Great Basin desert (Nevada and W. Utah)?
 Definition
Rain shadow
Term
Bauxite:
 Definition
Is a type of ore deposit formed by weathering and Forms only in tropical climates
Term
The Sahara desert that occupies much of northern Africa is an example of:
 Definition
A sub-tropical latitudinal desert.
Term
What is an aquifer?
 Definition
Rock that contains water in its open spaces and Rock that has enough permeability to allow water to flow through it.
Term
What distinguishes an estuary from other types of coastal embayment?
 Definition
they have rivers flowing into them.
Term
Which of the following types of ore deposit formed only once in Earth’s history?
 Definition
Banded iron formations
Term
In a river system, important differences between youthful and old-age topography include:
 Definition
Youthful rivers erode, old age rivers deposit sediments and Youthful rivers undergo flash floods, old age rivers undergo riverine floods.
Term
Which of the following accounts for the largest consumptive water use?
 Definition
Agriculture (irrigation)
Term
Which of the following relationships between inflow and outflow of water allows a fresh water lake to persist as a fresh water lake?
 Definition
precipitation + runoff EQUAL TO evaporation + outflow
Term
What is the most important reason why flood plains have been densely populated by humans since the Neolithic?
 Definition
Because periodic floods generate fertile agricultural soils.
Term
Which of the following is the level underground below which all open spaces in rocks are filled with water?
 Definition
water table
Term
What is a storm surge?
 Definition
A temporary rise in sea level caused by drop of atmospheric pressure in the eye of a hurricane.
Term
What is a cone of depression?
 Definition
A section of an aquifer where the water table has been drawn down around a water well.
Term
What is a littoral drift?
 Definition
Transport of beach sediments in a direction parallel to the shore.
Term
What is the difference between waves of oscillation and waves of translation?
 Definition
Waves of oscillation only move energy, waves of translation move energy and water.
Term
The relationship between a moraine and an outwash plain is:
 Definition
A moraine is made up of glacial sediment; an outwash plain is made up of moraine sediments transported by streams.
Supporting users have an ad free experience!