Introduction to Earth Science Final
Select the statements that are true regarding sea floor spreading.
- Faster-growing mid-ocean ridges have greater volumes than do more slowly growing ones. - Faster-growing mid-ocean ridges displace more seawater than do more slowly growing ones.
Identify statements true of glaciers.
- Glaciers last throughout the year - Glaciers are thick sheets of recrystallized ice - Glaciers are thick sheets of recrystallized ice that last throughout the year. There are two types of glaciers: mountain glaciers, which are found in or near mountainous regions, and continental glaciers, which can cover large parts of a continent. Although glacial ice is a solid, it flows like an extremely viscous fluid.
In the image below, what does the contact between the Unkar Group and Tapeats Sandstone represent?
- a surface formed by uplift and erosion of tilted older rock layers - missing time in the geologic record - an angular unconformity
Hydrothermal fluids
- arehcemically active solutions that can dissolve and transport ions - can change a rock's chemical composition in a process known as metasomatism - consist of hot water, steam, and supercritical fluid
Which of the following factors may contribute to desertification?
- drought - plowing - overgrazing
What a Geologist Sees This image shows folded layers of sandstone and shale in an outcrop of the Stellarton Formation (Pennsylvanian) near New Glasgow, Nova Scotia. None of the layers have been overturned. Which of the following freatures characterize and anticline?
- oldest beds crop out near hinge - limbs dip away from hinge - arch-like shape
The Earth's internal heat does which of the following?
- permits plate tectonics - keeps the lithosphere warm enough to flow - enables volcanism and mountain building - The Earth's internal heat keeps the lithosphere warm enough to flow, which permits plate tectonics, mountain building, and volcanism.
Which of the following decreases the chances of a mass movement?
- redistributing the mass on a slope by terracing - planting vegetation on slopes - pumping or draining water out of the ground along a slope
Identify the true statement about drainage divides
A drainage divide is a ridge that separates on watershed from another - Precipitation that falls on the west side of the continental divide flows to the Pacific Ocean. The Appalachians divide the Atlantic Ocean drainage from the Gulf of Mexico (not Arctic Ocean) drainage. The ultimate base level for streams on the east side of the continental divide, but to the west of the Appalachians, is the Gulf of Mexico (not the Pacific Ocean).
Which of the following statements is true? - a stream with a single channel is called a braided stream - meanering stream has many active channels flowing at once - a meander bend that gets cut off from the main channel becomes an oxbow lake
A meander bend that gets cut off from the main channel becomes an oxbow lake
Label the diagram depicting how salt and other evaporite deposits form in association with restricted bodies of water.
(From right to left) 1. open ocean 2. restricted basic 3. water evaporates (top) 4. new salt accumulates 5. desert
Label the types of minerals and their corresponding types of fractures. The leader lines indicate fractures
(from right to left) 1. irregular fracture 2. garnet 3. quartz 4. conchoidal fracture
Place the label that identifies the correct layer of the Earth on the following diagram
(From right to left) 1. inner core 2. outer core 3. lower mantle 4. upper mantle 5. crust
Match the three faults with their respective names.
(Top to bottom) 1. Reverse fault (moving into each other) 2. Thrust fault (sliding under/over) 3. Normal fault (sliding away from each other)
Describe the transformation from snow to ice by arranging the following steps in order
(first to last) 1. snow packs together 2. pressure melts snow 3. tightly packed firn forms 4. refreezing forms ice
What a Geologists Sees Match the adjectives for luster with the appropriate specimen
(from top to bottom) 1. glassy 2. metallic 3. earthy
This diagram shows an example of how rocks can change in the rock cycle. Which of the following properly defines the numbered processes?
(from top to bottom) 1. weathering, transport, and depostion 2. burial and heating 3. melting
The image shows photographs of sandstones taken with a petrographic microscope (a special type of microscope used by geologists). Match the description of sorting with the appropriate specimen.
(left to right) 1. Moderately sorted 2. Well sorted 3. poorly sorted
Rank each lava type according to the relative distance it can generally travel from a volcano vent before solidifying.
(left to right, least to greatest) 1. felsic 2. intermediate 3. mafic
Groundwater video labeling
(top to bottom) 1. Unsaturated zone 2. water table 3. subsurface bedrock or sediment (far left) 4. saturated zone (far right)
Part 1 Label the atoms in the silica-oxygen tetrahedron shown in the image below Part 2 The silica-oxygen tetrahedra is the building block of which chemical class of minerals?
(top to bottom) 1. silicon 2. oxygen silicates
Which of the following are methods used by geologists to predict a volcanic eruption?
- measuring an increase in heat flow - measuring an increased incidence of earthquakes - observing changes in the shape of a volcano - measuring an increased occurrence of gaseous emissions Changes in the shape of a volcano, increasing incidence of gaseous emissions and earthquakes, and an increase in heat flow may all signal that an eruption is imminent.
Scientists have been able to determine the numerical age of the most important events in history by using a combination of radiometric age dating and mathematical modeling. Please put the accompanying events in order from youngest (top) to oldest (bottom)
1. Formation of the Moon 2. Formation of the Earth 3. Nuclear fusion in the proto-Sun 4. Big Bang
Identify the statement that is true about soil-forming factors.
A young soil in an arid climate will be thinner that an old soil in a temperate climate
Identify the true statement
Most of the minerals in granite weather to clay except quartz
Intrusive igneous rocks
cool slowly an are coarse-grained - Extrusive (not intrusive) igneous rocks are fine-grained but cool quickly. Intrusive igneous rocks do solidify in the Earth but eventually are exposed by uplift and erosion. Basalt, andesite, and rhyolite are extrusive (not intrusive) igneous rocks.
If a sedimentary rock consists of carbon-rich remains of plants or other organisms, is it clastic, biochemical, organic, or chemical?
organic
Which of the following might be considered sediment?
shell fragments washed up on a beach
When you scrape a mineral along a ceramic plate to observe the color of its powder, you are checking the physical property known as
streak
Scientists can determine the direction of movement of continental glaciers by looking at glacial
striations - Striations, gouged by material on a glacier's bottom, are parallel to its direction of motion. Firn is packed granular snow and cirques and horns are landforms caused by glacial erosion.
(image shows two plates sliding past each other) What does this figure illustrate?
strike-slip faulting
The total sediment load of a stream includes
suspended, bed, and dissolved loards
Identify the correct labels for the sand dues illustrated in this diagram (sand 5 parts)
1. barchan 2. transverse 3. longitudinal 4. parabolic 5. star - Barchan dunes (1) are shaped like horseshoes with their opening facing downwind. Transverse dunes (2) are oriented perpendicular to wind flow. Longitudinal dunes (3) are oriented parallel to wind flow. Parabolic dunes (4) are also horseshoe-shaped but their opening faces upwind. Star dunes (5) radiate out in many directions.
The stream in this diagram flows at an average velocity of 6 feet per second. The area outlined by the dashed line is 800 square feet. The discharge of the stream is
4,800 cubic feet per second - Discharge = cross-sectional area × velocity = 800 square feet × 6 feet per second = 4,800 cubic feet per second.
Identify the true statement.
A 100-year flood has a 1% chance of occuring in any given year - Recurrence interval is related to annual probability. A 100-year flood occurs, on average, once every 100 years because it has a 1% chance of occurring in any given year. An annual probability of 4% means that there is a 1 in 25 (not 1 in 4) chance that a flood will occur. While the term recurrence interval may suggest that floods happen regularly, on predictable scales, it is possible for two 100-year floods to occur in consecutive years or even within the same year. The size of a flood and its recurrence interval are related directly, not inversely: the larger the flood, the greater the time between recurrences.
Identify the statement that is true about mass extinctions.
A mass extinction may happen when a comet or asteroid impact starts a chain of events that blocks sunlight for weeks or even years. - Extinction events are times in the Earth's history when large numbers of species abruptly disappeared. Superplume activity in Siberia (not volcanic eruptions in Hawaii) coincides with the extinction of more than two-thirds of the species on the Earth during the Permian-Triassic boundary extinction event. Dinosaurs, however, became extinct at the end of the Cretaceous (K-Pg boundary), which was 65 million years ago and associated with the Chicxulub crater in Yucatán, Mexico.
The Appalachian mountain belt formed due to the
Alleghanian orogeny - The Himalayan orogeny uplifted the Himalayas and Tibet during the Cenozoic. The Antler orogeny affected what is now western North America during the Devonian. The Sevier orogeny affected western North America during the Cretaceous. The Appalachian mountain belt formed in eastern North America and was caused by the collision of western Africa with eastern North America during the Carboniferous-Permian Alleghanian orogeny.
__________ deposits are wedge-shaped deposits consisting of coarse sediments and a large amount of feldspar, typically at the foot of an eroding mountain range, whereas _________ deposits consist mostly of clay and the skeletons of planktonic microorganisms.
Alluvial-fan; deep-marine
Identify the true statement associated with this diagram
Apparent polar-wander paths for different continents do not match, so each continent must be moving independently of the others
Which of the following images best shows how the Moon was formed?
C (rock is crashing into earth)
Which of the following statements is true?
Carbon dioxide concentration of the atmosphere has increased in the last century. - If global warming continues at current rates, by 2050 the average annual temperature will increase by 1.5° to 2°C, not from 15°C to 20°C. Researchers have used many different climate models that have produced conflicting scenarios of future climate. No single model has been proved to be the best, although all models suggest that significant temperature increases are expected by 2100. Very few climate scientists believe that the current temperature increases are due entirely to natural cycles that can be attributed to short-term climate changes.
In order to answer this question, you'll need to watch the Introduction of the Types of Faults Animation. Click here to access the Types of Faults Animation. Sort attributes according to whether they are associated with faulting or folding.
Faulting - earthquakes, fracturing, and brittle deformation Folding - ductile deformation
Identify the true statement. A. Regolith makes stronger slopes than bedrock. B. Slopes may be made more stable by undercutting. C. Vegetation is heavy, and therefore deforesting an area can help keep slopes stable. D. Forest fires followed by heavy rains are likely to result in severe mud and debris flows.
Forest fires followed by heavy rains are likely to result in severe mud and debris flows - Undercutting a slope removes its support and makes it less stable. Regolith is unconsolidated material that is more susceptible to mass movement than bedrock. The roots of plants often help to hold regolith in place on slopes; therefore, removing trees and vegetation (by deforestation or forest fires) can actually increase the risk of mass movement, especially if the regolith is saturated with water.
Which of the following statements is true?
Fossils of modern humans (Homo sapiens) date back about 200,000 years - Hominins did not appear in the late Mesozoic; even ape-like primates didn't appear until well into the Cenozoic. The human genus, Homo, first appeared about 2.4 million years ago. The Cenozoic (not the Mesozoic) is the Age of Mammals; the Mesozoic is the Age of Reptiles.
Identify the true statement.
Glaciers can undergo ablation by melting , sublimation, or calving - Ablation is the removal of ice and is the opposite of accumulation of more snow falling than melting. Glaciers (especially at high latitudes) can reach sea level. When a glacier retreats, the position of the toe moves back, but the ice continues to flow in the same direction.
Select the statement that best describes glacial movement
Glaciers flow like an extremely viscous fluid by undergoing internal plastic deformation. - Although glacial ice is a solid, it flows like an extremely viscous fluid by undergoing internal plastic deformation resulting from pressure and the force of gravity.
Which of the statements explains why glaciers create valleys with a distinctive shape?
Glaciers rose and pluck from the entirety of the valley floor - Glacial valleys have a distinctive U-shape because glacial ice fills much of the valley and removes material from the valley floor and walls. The stream-carved valley is V-shaped because the river can erode only in a relatively narrow channel at the floor of the valley; mass wasting of the valley walls causes the slope to approach that of the angle of repose. Glaciers carve U-shaped valleys because glacial ice is actively eroding both the valley floor and the sides of the valley.
According to this graph, which of the following statements is true?
Global sea-level change during the Paleozoic was on the order of 250 m. - Present-day sea level is actually low when compared to peaks such as the one during the Cretaceous. Sea level was low during the late Paleozoic/early Mesozoic, a time that coincides with the assembling of the continental landmasses into a supercontinent called Pangaea. Cenozoic sea level has decreased (not increased) throughout the era. Global sea-level change during the Paleozoic was on the order of 250 m.
Experiment with the simulation to categorize the impacts of different levels of precipitation in the zone of accumulation. To do this, begin by placing the sliding bar halfway between the high and low settings for precipitation. Then, increase or decrease the amount of precipitation by slowly sliding the bar either upwards or downwards. Pay careful attention to the changes in glacial ice thickness and rates of motion as you do this. Sort the impacts associated with high and low levels of precipitation. Items (4 items)
High Precipitation Levels - Glacial ice thickens - Glacial flow rate increases Low Precipitation Levels - Glacial ice thins - Glacial flow rate slows
Which of the following statements is true?
Icebergs, by definition, are free-floating chunks of ice that are at least 6 m above water and at least 15 m long - A full 80% of an iceberg lies below the surface. Icebergs float because ice is less dense than water. A tidewater glacier is one whose toes lie in the water; they do not move by tides.
Identify the true statement.
Increased CO2 in Earth's atmosphere, caused by the burning of fossil fuels, is accelerating the rate of glacial retreat. - The Pleistocene Ice Age ended about 12,000 (not 100) years ago. Continental glaciers are found in Greenland and Antarctica (not South America). Global temperature has been warming since about 1850; the rise in temperature is attributed to the release of CO2 into the atmosphere caused by the burning of fossil fuels.
Why is carbon dioxide called a greenhouse gas?
It allows solar radiation to reach Earth but absorbs and traps the infrared radiation re-radiated by Earth. - Carbon dioxide is called a greenhouse gas because, like the glass of a greenhouse, it allows solar radiation to reach the Earth, but it traps some of the infrared radiation that the Earth emits.
Which of the following statements about permafrost is true?
It can melt to a depth of a few meters in summer, and then refreeze in winter - Permafrost is very common in periglacial environments. It extends only meters below the ground surface. Columnar jointing is a volcanic phenomenon caused by cooling lava, not the thawing and refreezing of permafrost. (Review Chapter 5.)
What is true of the ozone hole?
It is caused by the destructive reaction of chlorofluorocarbons (CFCs) with ozone in the atmosphere. - The ozone hole is a zone of depleted (not completely removed) ozone in the atmosphere that occurs over the poles, not the equator. It is caused by CFC emissions into the atmosphere, which react with tiny ice crystals to destroy atmospheric ozone. Ozone blocks harmful solar ultraviolet radiation. The ozone hole does not cause global warming.
Which of the following statements has been asserted in IPCC reports?
It is extremely likely that human activity has contributed significantly to global climate change. - Natural, non-anthropogenic forcing cannot explain the change in global climate that scientists have observed.
In which time period did the first feathered birds appear?
Jurassic - The first feathered bird, called Archaeopteryx, didn't appear until the Jurassic Period of the Mesozoic Era.
Rank the following areas in order of largest to smallest change in average temperature since 1880.
Largest to smallest 1. northern Canada 2. western Europe 3. Australia 4. southern africa 5. eastern Pacific Ocean 6. Antarctic Ocean
The hottest verified temperature on the Earth, measured at 58 degrees C, (136 degrees F), was in
Librya, Africa - The hottest temperature in Death Valley was 57°C (133°F). The hottest in the world was recorded as 58°C (136°F) in Libya, Africa.
From the rock layers shown in this diagram, it is logical to say that oil would most likely be found in which location?
Location B (reservoir rock)
The rocks on this map that underwent the deepest burial are now exposed at the surface in which state?
Massachusetts
Identify the true statement.
Narrow, steep-sided, deep inlets of seawater in glacial valleys are called fjords. - The process by which icebergs form is called calving, not surging. Today, 10% of land is covered in ice; in the ice age, 30% was. Pluvial lakes, like those that existed during the Pleistocene Ice Age, were far from glaciers and existed because of wetter climate conditions.
Categorize processes that may result in sedimentary rock formation versus those associated with hard-rock (igneous and metamorphic) formation.
Sedimentary Processes -erosion of a sedimentary rock -weathering of exhumed metamorphic rock Hard Rock Processes -deep, high-pressure burial of sediments -partial melting of the crust
Reservoirs in the carbon cycle are often described as being sources or sinks of carbon, depending upon whether they release or absorb carbon, respectively. Sort the various statements based on whether they describe a carbon source or sink.
Source - limestone rock weathers on a hillside - volcano erupts - leaf litter on the forest floor decays - electricity is produced at a coal-burning power plant Sink - a clam builds a new layer of shell - living trees in a forest undergo photosynthesis
P- and S-wave arrival times are indicated on seismogram records for three stations. Which of the three stations shown below is farthest from the earthquake that generated the waves?
Station 3 (longest one)
Identify the true statement.
The angle of repose is the steepest angle at which unconsolidated sediments can sit without slipping downhill. - Lahars are mudflows associated with volcanic activity, not earthquake shaking. As the name implies, the head scarp of a slump is found near the top of the slump block; the base of the slump block is called the toe. Slow movement of unconsolidated material downslope is often characterized as creep, not a turbidity current.
What a Geologist Sees The wall of this quarry near Seneca Falls, N.Y. exposes a thrust fault that cuts across bedding in the Onondaga Limestone. Because the beds of limestone all look much the same, the trace of the fault is somewhat hard to see. This fault has a dip (slope) of about 15° to 20°. (Thrust Fault in Onondaga Limestone Cutting Upward into Marcellus Shale, Seneca Falls, N.Y.
The fault dips to the south
In this illustration, which is a correct interpretation of relative ages?
The grainte pluton is older that the fault, which is old than the dike
Which of the following statements is true?
The level of the water table can drop when surface water is diverted away from recharge areas - On the scale of human lifespans, groundwater is considered a nonrenewable resource because we are using it faster than it can be replenished. Freshwater is less dense than saltwater, so saltwater invading a coastal aquifer moves in under the freshwater. Pore collapse occurs when water that normally fills pore space is removed; since water acts to hold grains apart, when it is removed the pores collapse and the porosity of the rock decreases. Remember also that water cannot be compressed.
Which of the following statements is true?
The most extensive deposits of coal occur in Carboniferous-age strata - Fossil fuels store solar energy that reached the Earth long ago and was converted to organic matter through photosynthesis. Coal rank is based on the carbon (not sulfur) content of the coal and is related to the amount of energy released when the coal is burned. Renewable means on a human time scale, not a geologic one; oil and coal are both forming in today's world, but too slowly to replenish themselves as we use them up.
Which of the following is an accurate description of a method used to study short-term climate change?
The oxygen-isotope ratios of glacial ice record changes in global temperature for the past 800,000 years. - The thickness (not the color) of a tree ring indicates the growth rate in any given year. Pollen is commonly preserved in lake sediment and can be used to characterize climate change over thousands to millions of years.
How does the rate of groundwater flow compare with that of ocean currents or river currents?
The rate of groundwater flow is slower than that of surfae-water currents - The rate of groundwater flow is very slow compared to that of currents in surface water, generally moving at less than 1-1.5 meters per day.
Which statement is true regarding this diagram? (sand diagram, a to b)
The wind is blowing from slope A toward Slope B - The wind carries sand up the windward side of the dune (Slope A), which falls down the slip face (Slope B), creating the layers of cross bedding seen in the diagram. The wind direction is from A to B.
Dunes form when currents (wind or water) move in one direction. Much like asymmetrical ripples, they have a gentle slope on the upstream side and a steep slope on the downstream side (slip face). Use the shape of this dune to select the statement that most accurately describes the wind direction in the image.
The wind was blowing from left to right
Of the choices below, select the one that accurately pairs the feature with the type of plate boundary at which it occurs.
Trenches occur at subduction zones
What does the term uniformitarianism mean?
We can inerpret the processes that formed ancient rock by examining the processes that form similar rock today
Which statement is true based on the following diagram?
Well B would yield the most oil because it's on an anticline crest in permeable reservoir rock - Oil flows to the top of an anticline and stays there (anticline trap). Deeper wells that are drilled away from the anticline hinge may miss this oil. Source rock is not permeable, so it prohibits flow into the well.
Scientists estimate the recurrence interval of eruptions at Yellowstone caldera is about 730,000 years. Which of the following statements best describes the recurrence interval of Yellowstone caldera?
Yellowstone erupts on average about every 730,000 years, but it may erupt sooner or later than that - There have been three eruptions from Yellowstone caldera: one 2.1 million years ago, one 1.3 million years ago, and one 0.64 million years ago. The time between eruptions is 0.8 and 0.66 million years, respectively. Thus the recurrence interval is 0.8 million years + 0.66 million years2=0.73 million years or 730,000 years0.8 million years + 0.66 million years / 2 =0.73 million years or 730,000 years
A nonmarine clastic sedimentary rock composed of angular pebbles surrounded by matrix would be
a breccia
The Deepwater Horizon disaster was
a catastrophic blowout that occurred in April 2010 in the Gulf of Mexico. - he Deepwater Horizon disaster was a blowout of a BP oil rig in the Gulf of Mexico in 2010. The other choices describe recent events involving energy that you may have heard about in the news over the past few years (abundant earthquakes in Oklahoma ranging from magnitude 2 to 4.5 due to fracking, the meltdown of the Fukushima nuclear reactor in Japan, and the Exxon Valdez spill off the coast of Alaska).
The Himalayas are growing because
a continental plate is colliding with another continental plate there
Which of the following climate conditions would most likely allow glaciers to form?
a heavy snowfall in winter, coupled with relatively cool summers - Glaciers need a lot of snow that doesn't all slide or blow away when it falls, or melt away in the summer.
The chain of the Hawaiian Islands extends northwest across the Pacific as shown in the figure. The island of Hawaii is the youngest, and the islands get progressively older to the northwest. Plate tectonic theory explains this as
a hot spot currently sitting under Hawaii and the Pacific Plate moving across it in a northwesterly direction
Which of the following is a desert most likely to have?
a location at latitude 30 degrees N or S - Latitude 60° N is an area of convergence and rainfall. Deserts have high evaporation rates and little to no plant life to provide transpiration.
The Late Devonian fossil shown in this image, Tiktaalik, is significant because it represents
a transition from lobe-finned fish to amphibians that could walk on land - Tiktaalik roseae is a transitional fossil of a lobe-finned fish that began to develop wrists suitable for walking on land and is one of the first amphibians in the fossil record.
Riprap added to the base of a steep slope
absorbs wave energy and can slow the undercutting of coastal cliffs - Riprap (large boulders or concrete) can absorb the energy of waves and streams, slowing the rate at which they can undercut the slope and cause it to fail. Riprap has no effect on slope stability (other than to prevent the slope from being undercut), is not used to prevent avalanches, and cannot cause a rockfall.
Which of the following statements is true? A. All of the possible answers are correct. B. Overconsumption of Colorado River water has caused the river to become nearly dry where it crosses the Mexican border. C. Damming a river decreases the amount of sediment and nutrients the river carries downstream of the dam. D. Urbanization can increase the risk of flash flooding.
all of the above
Which statement(s) is true about igneous rocks?
all of the possible answers are correct - Igneous rocks form from molten rock or lava, so they may be found around volcanoes.
What physical characteristics can be used to distinguish individual rock types?
all of the possible answers are correct - Rocks are differentiated and named on the basis of physical characteristics that include composition, texture, grain size, grain shape, and layering.
Magmas can have a variety of chemical compositions for which of the following reasons?
all of the possible answers are correct - The factors affecting magma composition are melt source, degree of partial melting, assimilation, and magma mixing. Three of these are listed in this problem.
Even though earthquake prediction is not highly reliable, what do geologists know about them?
all of the possible answers are correct -Earthquakes occur with greater frequency along plate boundaries than in intraplate locations. The reciprocal of the recurrence interval between earthquakes (in years) is an estimate of the annual probability that an earthquake will occur. So, we can estimate the probability of an earthquake occurring over a set period of time, but not exactly when it will occur.
Which of the following would increase the risk of having a landslide? - adding support to the toe of a slope - allowing water to infiltrate a slope - recontouring a slope to reduce its slope angle - removing weight at the top of a slope
allowing water to infiltrate a slope - All the other choices would help prevent a landslide.
Which of the following is a typical oil trap?
an anticline - Oil rises because of buoyancy and would not settle at the bottom of a syncline; the heat of igneous activity would destroy any oil formed.
The snake-like hill in the photo consists of sediment deposited in a meltwater tunnel beneath a glacier. It is called
an esker - Moraines are deposits of glacial till. A ground moraine is a sheet of poorly sorted sediment deposited beneath a glacier and left behind when the ice melts. Kettles and knobs are the result of blocks of ice melting within glacial till. Braided streams form downstream of a glacier, not within it.
This graph shows average global temperature as measured in shallow ocean water. The overall increase in average temperature has been accompanied by, and attributed to, which of the following trends in greenhouse gases?
an increase in both CO2 and methane - The overall increase in global temperature has been accompanied by an increase in greenhouse gasses. These increases have been particularly dramatic in the decades following the industrial revolution. CO2 levels have increased due to human activity such as burning fossil fuels, making cement, and clearing forests. We have also caused increased methane levels via agricultural activities, livestock production, and fossil fuel production.
If significant global warming happens, the consequences will include
an interruption of ocean currents and the heat transfer they accomplish. - Climate belts will shift, but the shift of temperate climates will be to higher latitudes, not lower. Stronger storms and increased flooding will result, and sea levels will increase because of melting ice.
Deltas
are made of a sediment depositied near the mouth of a stream - Alluvial fans, not deltas, form when ephemeral rivers deposit sediment onto a flat plain at the base of a mountain range. Deltas contain distributaries that flow out to sea from a trunk river, not into it. Frequent floods on these distributaries add sediment to the delta, making new land and keeping it above sea level.
Ore deposits
are rock units that have a significant concentration of metals - While some ore deposits may contain ore minerals with a high amount of lead (Pb), they can have concentrations of various types of metals (not just lead). Ore deposits do not uniformly occur in the crust. Ore deposits are mined specifically because the metals within them are concentrated (not diffusely bonded to nonmetallic elements in a variety of minerals throughout the deposit).
Which of the following is a dry water channel or basin?
arroyo - A haboob is a dust storm. Badlands are barren landscapes covered in a network of drainage channels for ephemeral streams. A mirage is a fake image of shimmering water, produced when a surface hot-air layer refracts sunlight.
The black, fine-grained tabular intrusions between layers of horizontal sedimentary rock shown in this picture are
basaltic sills
The Earth's atmosphere
became more oxygen-rich during the Proterozoic, after the evolution of photosynthetic organisms in the Archean. - The Earth's early atmosphere, after the initial hydrogen and helium from the solar nebula dispersed, consisted mainly of carbon dioxide and water vapor. The atmosphere acquired oxygen (not carbon dioxide) from the photosynthetic process, and it warms when its carbon dioxide concentration goes up, not down.
Wegener's theory of continental drift took decades to be accepted
because Wegener couldn't explain how continents moved
Grains that move by saltation
become rounded and frosted by knocking into other grains - and grains, not fine-grained dust and silt, move by saltation. The grains bounce along the ground (saltation) but never rise more than 2 meters. Dust devils occur when fine-grained particles are moved as suspended load.
What do the Sahel of today and the U.S.-Canada Great Plains of the 1930s have in common?
being subject to natural and human-induced desertification - The two locations do not have a common factor of large dunes, extremely low rainfall, or large amounts of sand.
In this illustration, (layer B and block X)
block x is the hanging wall
Which of the following is a method to prevent mass movements? - bolting loose rock to its substrate - increasing the level of the water table by building a dam - adding weight to the top of a slope - removing slope terraces
bolting loose rock to its substrate - Adding weight to the top of a slope, increasing the level of the water table, and removing terracing will all increase the likelihood of mass movement. Bolting loose rock to its substrate will anchor it to bedrock and prevent it from moving.
Sedimentary rocks form
by grains being cemented together -Igneous (not sedimentary) rocks form from lava or magma. Sedimentary rocks would become metamorphic rocks if they were exposed to high heat and high pressure deep in the Earth.
The reaction to acid can be an important diagnostic test when identifying minerals. The photo shows a mineral that "fizzes" when an eyedropper is used to apply acid. Which of the following minerals is most likely shown in this photo?
calcite
Avalanches
can be triggered by explosions, people, or even just new snow - Avalanches move quickly and can be triggered by explosions, skiers, or even new deposits of snow. As defined by geologists, avalanches are mass movements in which solid fragments (of rock, ice, etc.) are suspended in a fluid (air or water) so that the mixture behaves like a turbulent cloud. Pathways created by avalanches are called avalanche chutes, and avalanches typically run down the same chute many times.
Liquefaction
can cause wet, silty, or sandy sediment to turn into an unstable slurry
Which of the following elements is released into the atmosphere by volcanic outgassing, animal flatulence, production of cement, and metamorphism of limestone?
carbon - All of these elements are involved in biogeochemical cycles, but only carbon cycles among solid, liquid, and atmospheric Earth reservoirs via all of these processes.
Which of the following processes forms biochemical sedimentary rock?
cementing together of shell fragments
Which of the following classes of sedimentary rock is produced by weathering and erosion of pre-existing rocks?
clastic
Plant material (leaves, stems, trunks) in oxygen-poor swamps are buried for a geologically long time. The result is
coal - Kerogen, tar sands, and petroleum are all energy resources that began as microscopic marine organisms, not as leaves, stems, or tree trunks.
The Gobi Desert, in the interior of Asia, sits more than 2,000 km away from the nearest ocean and is therefore a good example of a
continental - interior desert - Because it sits far away from an ocean, the Gobi Desert is an example of a continental-interior desert. It is not at high latitudes (a polar desert), nor is it in the rain shadow of a mountain range. Deserts that form because cold, dense air cannot rise to form clouds most often occur on coastlines and create coastal deserts.
(outer arrows pointing in while the middle arrow is pointing down) The figure shown here is a typical example of a _________ plate boundary
convergent
Which of the following is a method used to determine numerical age?
counting tree rings - Correlation (using either strata or fossils) and determining cross-cutting relations are both types of relative, not numerical, dating. By counting tree rings on a living tree, you can determine a numerical age for the tree because each ring represents a year of growth. This method is similar to counting annual layers in glacial ice, growth layers in shells, and annual layers in some types of sedimentary deposits.
Which of the following processes most logically explains the different tilts of gravestones in a hillside cemetery?
creep - Creep is the slow movement of the ground surface downhill.
Mafic minerals
crystallize at a higher temperature than do silicic minerals - Mafic minerals are rich in iron and magnesium (not aluminum and sodium), typically crystallize first (not last) out of a cooling melt, and form rocks like basalt and gabbro (not rhyolite and granite).
Oil forms when
dead algae and plankton deposited in low-oxygen conditions are buried and heated - Coal, not oil, forms from the decomposition of leaves, twigs, and trees. High levels of oxygen would lead to total decay of organic materials (and preclude the formation of oil). Despite popular media, oil does not form from the dead carcasses of dinosaurs.
The maps above show the numbers of days with temperatures above 32ºC for 1961-1971 (left) and the projected numbers of days for 2080-2099 (right). Using the maps as a guide, select the possible consequences of the predicted change in the numbers of days with temperatures above 32ºC.
decreased snowpack longer summers more droughts more heat waves
This photo (lens cap for scale) shows a fairly smooth, flat surface consisting of tightly packed stones with desert varnish. A surface like this is called
desert pavement - A surface like this is called a desert pavement. Desert pavements were once thought to be lag deposits, but recent research suggests that at least some of them may have been "born at the surface." An inselberg is bedrock and alluvium is sediment, making "alluvium inselberg" a contradictory nonsense term. A cuesta is an asymmetric ridge of resistant bedrock.
Shown here is an intact slab of rock destined to become a kitchen countertop. What is this type of mineral resource called?
dimension stone - Intact slabs of rock used for architectural purposes are called dimension stone.
All deserts are
dry - There are many kinds of deserts; the only thing they have in common is a dry condition.
Which term describes the current theory of earthquake formation?
elastic rebound
These isolated boulders were carried in glacial ice and then left on the landscape once the ice melted. They are called
erratics - Varves are seasonal layers in glacial lake deposits. Moraines are piles of unsorted sediment that are deposited along the sides and toes of a glacier. Moraines are made of glacial till. These lonely boulders are erratics.
The principle of fossil succession states that
every fossil species spans only a limited range of rock layers, corresponding to the time period over which it lived.
How is a fault different from a joint?
faults are fractures along which displacement has occurred; displacement does not occur along joints
Which of the following is a characteristic feature of deserts?
flash floods - Because of the lack of plant cover, deserts are highly susceptible to flash flooding during rainfall events. Deserts typically have thin (not thick) soils and no humus, and they undergo little chemical weathering because of the lack of moisture.
The rate at which temperature increases as depth increases is the
geothermal gradient
Which of the following earthquake phenomena is the LEAST likely to directly injure or kill humans?
ground shaking
The Vaiont Dam Disaster
happened because a properly engineered dam was built in a geologically unstable location - The disaster happened in the 1960s in Italy. There was so much slope movement before the slope failure that the locals called Monte Toc "the mountain that walks."
Metamorphic rock
has changed physical characteristics while remaining solid - Igneous rocks form from a melt. Metamorphic rock forms by changes to the physical characteristics of pre-existing rock in the solid state. Sedimentary rocks often contain bedding, and metamorphic rocks often contain foliation. Although metamorphic rocks do form in mountain belts, there are many other places where they can form (for example, the subduction zone in Figure A.4).
Global human population
has doubled at an accelerated rate since the industrial revolution - The global human population has been growing (not shrinking) at an accelerated rate since the industrial revolution and has been doubling over shorter and shorter periods of time. As standards of living improve, the growing population uses more resources per capita, not less.
Low-viscosity lava
has low silica content - The viscosity of lava relates to the silica content; the silicon-oxygen tetrahedra link together in chains that tangle and make movement difficult. Thus, low-viscosity lavas do not contain a lot of silica.
This image shows a close-up view of a piece of pumice that was washed up onto a beach in Italy. Which of the following sets of properties allow this volcanic rock to float on water?
high porosity, low permeability - This rock exhibits high porosity due to the abundant gas bubbles (pore spaces), which give the rock an overall density that is less than that of water. Despite their abundance, the open spaces are not connected, so the rock has a low permeability. This combination of traits makes the rock very lightweight and keeps the water from forcing air out of the pores and filling them.
Which of the following rocks is nonfoliated? - slate - schist - phyllite - hornfels
hornfels -Hornfels is nonfoliated rock because it forms at high temperature and low pressure in the absence of significant differential stress.
Which of the following chemical reactions breaks down feldspars into clay?
hydrolysis
Which of the following sequences explains the transition path of a rock that first experienced melting and cooling, then burial to deep depths during mountain building, and finally uplift and weathering?
igneous, metamorphic, sedimentary - The key words melting, burial, and weathering indicate that this pathway describes igneous, then metamorphic, and then sedimentary rock formation.
A typical longitudinal profile of a stream
illustrates that a stream's gradient is steeper near its headwaters than near its mouth - A profile shows the cross section along the stream's entire length, not just at one site. A typical longitudinal profile is steepest near the headwaters and flatter near the mouth, which means that most streams have higher slopes at their headwaters than near their mouths.
The Paleozoic Era ended with a mass extinction even that was likely caused by
intense volcanic activity - The late Paleozoic (Permian Period) extinction was most likely due to intense volcanic activity in the region that is now Siberia.
Mass movement
is a gravity-driven downslipe movement of natural materials - There's abundant evidence of submarine mass movements, including submarine slumps, debris flows, and turbidity currents. Wet conditions, rather than dry conditions, help to move material downslope because an increase in moisture decreases friction by pushing grains apart. Certain types of mass movement, like creep and solifluction, can happen on shallow slopes
Solifluction
is a kind of creep that's found in high-elevation regions or in the Arctic on slopes that are underlain by permafrost. - Solifluction is caused by thawed ground sliding above frozen ground (permafrost).
A seal rock
is a necessary ingredient of an oil trap - Fractured or poorly cemented rocks would be good reservoir rocks, but would have high porosity and high permeability (potentially) and therefore would be poor seal rocks. Because it is less dense than the water filling the pore spaces in rocks at depth, oil migrates upward (not downward).
The crystallization of salt from evaporating seawater
is an example of precipitation from a solution - Salt is the result of precipitation from a solution. Salt (NaCl) is a halide mineral (not a silicate) that forms cubic (not hexagonal) crystals that precipitate from saturated (not undersaturated) solutions.
A drainage network
is an interconnected group of streams that collects water over a large area. - A trunk stream that cuts across a resistant ridge is called a water gap (like the Delaware Water Gap). It's a dendritic network, not a trellis network, that forms over uniform substrate with a gentle slope. A drainage network is a collecting basin for area precipitation and a series of channels to conduct the water out of the area and toward the sea (but it does not necessarily empty directly into the ocean).
Quartzite
is basically a solid mass of interlocking quartz grains
A crystalline rock
is composed of interlocking minerals that grew together
Oceanic crust
is covered by a thin blanket of sediment that thickens away from the ridge axis
Granite
is felsic in composition - Granite is a felsic, intrusive (and therefore coarse-grained) igneous rock. It is often found as plutons rather than lava flows, which are extrusive. The coarse-grained equivalent of andesite is diorite, not granite.
Geologists base their estimate that the Earth is 4.56 billion years old on:
isotopic dating of meteorites thought to be from primitive solids of the early solar system - Geologists assume that all objects in the Solar System developed at roughly the same time; therefore, the age of differentiated meteorites should represent the age at which the Earth formed. Although no 4.56-Ga rocks have yet been found in Earth's crust, some sand grains of the mineral zircon have ages of 4.4 Ga, and Moon rocks have yielded ages of up to 4.5 Ga.
Identify the statement that is true about wind abrasion
it can produce faceted rocks (ventifacts) - A wadi is a dry wash carved by running water, lag deposits are materials left behind by wind erosion, and streams create alluvial fans.
Identify the statement that is true about a reservoir
it is a component in the Earth System that holds material for a period of time
What a Geologist Sees? The image shows cross beds in the Navajo sandstone in Zion National Park. Note the person for scale near the bottom right corner of the image. Which of the following best describes the direction that the wind was blowing when these cross beds were formed?
left to right
What is the protolith of marble?
limestone
Which of the following statements about lithosphere and asthenosphere is true?
lithosphere consists of the crust and the upper mantle and behaves like a rigid payer that breaks or bends rather than flowing like the asthenosphere
A tsunami
may be just a broad, gentle swelling out at sea but grows as it approaches shore -caused by volcanic or seismic activity or by undersea landslides. They can get tens of meters high, and they can cross entire ocean basics.
Submarine slumps like the ones highlighted in the image
may displace enough water to create a tsunami - Submarine slumps like the ones that surround Hawaii consist mostly of rigid blocks seen as lumps on the seafloor, not mixtures of suspended sediment like a turbidity current. The blocks may move 150 km or more from the islands, as shown by the map scale, and displace enough water to generate a tsunami that may have drastic effects on land along the shoreline.
A metamorphic rock
may have preferred mineral orientation caused by different stress
Desertification
may occur when human population exceeds the carrying capacity of the land - Desertification can be enhanced by natural events, like drought and wind erosion, but it is driven primarily by human activities such as overgrazing and inappropriate farming practices. It can occur in both less-industrialized regions and industrialized nations like the United States. It is a rapid process of transforming non-desert areas into desert and can occur within a few decades.
Magma may cool and crystalize to become solid igneous rock
more slowly in a deep pluton than in a shallow sill - Magma will cool and freeze when its volatile content decreases, not increases. It will cool faster (not slower) in the presence of circulating groundwater, and it will cool faster if the surface area of the intrusion is high, not low. The deeper the magma (such as a deep pluton), the longer the cooling time.
Which of the following lists accurately reflects an increase in grain size from smallest to largest?
mud, silt, sand
Metallic and nonmetallic mineral resources are considered nonrenewable because
natural processes make minerals much more slowly than we can mine them
The center of a mid-ocean ridge is where
new oceanic lithosphere is created
What changes in the crust do scientists look for when using seismology and seismic networks to mitigate volcanic hazards?
noise/vibrations caused by magma moving through rocks - When magma beneath the ground begins moving, it causes "noise" as rock around it breaks and moves. These seismic waves travel through the surrounding rock as vibrations that can be picked up by seismic sensors.
What type of unconformity occurs when sedimentary rocks overlie either igneous or metamorphic rocks?
nonconformity
Which of the following terms refers to the process of mountain building?
orogeny
Which of the following is a mineral?
oyster shell (CaCO3) - The hard material that makes up an oyster shell fits the definition of a biogenic mineral. Amber and sugar have organic origins, and glass is not crystalline.
In which order does coal develop?
peat, lignite, bituninous coal, anthracite - Coal develops from peat, which turns into lignite, then bituminous coal, and then anthracite coal.
The various geological settings in which rocks can melt, metamorphose, or become sediment are ultimately generated by
plate tectonics - Plate interactions, as a result of plate tectonics, ultimately generate the various geologic settings where Earth materials can melt, metamorphose, or weather to become sediments.
Which term applies to temporary desert lakes?
playa - A bajada is sediment layers built up by alluvial fans. Blowouts are a result of wind deflation. An inselberg is a mountain range that is partially buried by sediment.
Identify possible consequences of rapid groundwater withdrawal
pore collapse occurs, wells go dry, and a cone of depression forms
Which of the following terms has to do with extrusive igneous activity?
pyroclastic - Pyroclastic rocks are igneous rocks with a fragmental texture formed by explosive volcanic eruptions. The other terms describe intrusive bodies or their components.
Stratigraphic correlation
relates layers in different places that are the same age, regardless of how different they look.
The oil window is the
relatively narrow range of temperatures in which oil can form: 90°C to 160°C. - The oil window refers to temperature and pressure conditions necessary to form oil, not to a time period when oil formed. Oil forms no deeper than 6.5 km; gas, no deeper than 9 km. Oil enters the drilling apparatus through various methods, none of which are called an oil window. Natural gas forms between 160°C and 250°C; above 250°C, organic matter transforms into graphite.
Identify outcomes of the rock cycle
rocks are recycled over geological time very few old rocks are present on the surface of the Earth
What is a typical reservoir rock into which oil can migrate and collect?
sandstone - Sandstone is a good reservoir rock because it is porous and permeable. Shale is impermeable and would not permit oil to move into or through it. Granite and basalt are igneous and metamorphic rocks, respectively, and the heat involved in the processes that create them destroys any material that might develop into oil.
What is the name of the type of foliation that is defined by the preferred orientation of large mica flakes, as shown in the photo (looking down on the foliation plane)?
schistosity
As transgression occurs at a given location,
sea level rises, a mud layer accumulates over a sand layer, & the coastline migrates inland
The principle of lateral continuity says that
sedimentary layers began as continuous expanses of sediment
A petrographic microscope
sends transmitted polarized light through a thin section of rock - The function of a petrographic microscope is to examine mineralogy of a sample in thin section by sending transmitted polarized light through the specimen. To examine samples in a hand specimen, a hand lens is used. To map the distribution of elements within a rock sample, a scanning electron microscope is used. To analyze the atomic weights of elements within a sample, a mass spectrometer is used.
A typical source rock of oil, which started out as mud in which dead organic matter settled, is
shale - Granite is a plutonic rock and contains no organic matter. Conglomerate and sandstone don't represent the oil-forming environment necessary, which is mud at the bottom of standing water.
Bowen's reaction series
shows that minerals in a cooling magma crystallize in a predictable order. - Bowen's reaction series was deduced through laboratory procedures that cooled molten rock. The crystal formation in the resulting igneous rocks followed a predictable order because as a magma crystallizes, the remaining melt becomes more enriched (not depleted) in silica.
Identify the list of rock types that is ordered by increasing degrees of metamorphism (i.e., from lower to higher grade).
slate, phyllite, schist, gneiss
What are slides with a spoon-shaped (concave side up) surface called?
slumps - Creeps are slow movements of material down a slope. Debris flows and avalanches are well-mixed flows of material that travel downslope above the land surface. A slump is a body of earth that moves above a concave-up slip surface.
The tragedy in 1970 at Yungay, Peru,
started with an earthquake that triggered an icefall that in turn triggered a debris flow. - Previous slides had occurred there, as is evident from the "Before" photo in Figure 13.1a. Mass wasting (mass movement) can be slow or fast. The former site of the town is now a grassy meadow.
What a Geologist Sees. This image shows fossils from the Hoyt Limestone, a Cambrian formation in eastern New York. Which of the following best describes the organism that formed this fossil?
sticky cyanobacteria that got coated with sediment - This stromatolite fossil was originally composed of alternating layers of organic material and lime mud.
Which of the following statements about differentiation are true?
the core formed as a result of differentiation the mantle formed as a result of differentiation
Which of the following is an example of anthropogenic change?
the current global warming trend - The current global warming trend is the result of the large-scale burning of fossil fuels by humans.
Landslides are likely to happen when
the downslope force becomes greater than the resistance force - The angle of repose of sandy slopes is 30° to 37°, sliding happens on weak surfaces that parallel (not dip into) the slope, and adding weight to the top (not bottom) of a slope may trigger movement.
The genetic scheme for classifying rocks is based on
the origin of formation
Which of the following is a characteristic of all rocks?
they are a collection of minerals or a body of glass
The global occurrence of earthquakes reveals that
they usually occur on the boundaries of plates or at hot spots
Groundwater
typically moves slowly within the ground through permeable rock layers like sandstone - The zone of saturation is below (not above) the water table. Groundwater moves mainly through interconnected pore spaces in rock and sediment, rarely in underground lakes or streams. Shale is porous, but not permeable like sandstone; therefore, water flows more slowly, or not at all, through shale.
Which statement is true according to the rock cycle?
uplift, weathering, burial, and heating/melting can transform one rock type into another - The rock cycle, by definition, explains how Earth materials change from one type to another, and it occurs because the Earth is a dynamic and changing system. Since continental crust cannot subduct, not all rocks in the crust will subduct, melt, and eventually form igneous rocks.
According to Milutin Milankovic, which of the following caused glacial-interglacial cycles during the Pleistocene?
variations in teh shape of the Earth's orbit - All of Milanković's ideas involved aspects of the Earth's movement around the Sun.
In this image of a metamorphic rock viewed through a petrographic microscope, the preferred orientation of the mineral grains is ________, indicating that the direction of greatest compression was oriented ________.
vertical; horizontally
Lahars are a volcanic hazard that can occur both during an eruption and while a volcano is dormant. Which event below must happen for a lahar to form while a volcano is dormant?
very heavy rainfall over the dormant volcano
The eruption of Mt. St. Helens in 1980
was triggered by a landslide on its northern flank - The Mt. St. Helens eruption occurred after many months of warning signs, including a bulge on the northern flank of the volcano that collapsed into a landslide, triggering the eruption. The lateral blast of steam, rock, and ash that followed flattened forests over a broad area. Although it was a major eruption, Mt. St. Helens was quite small compared to other historical events such as Krakatau and Tambora.
The atmosphere contains many different gases; some of these are greenhouse gases, in that they trap heat in the atmosphere, and some are not. Which of the following gases contribute to the greenhouse effect?
water vapor (H2O) methane (CH4) carbon dioxide (CO2)