Geology final
Chemically precipitated limestone that forms in caves or around hot springs is termed ________. a. dolostone b. agate c. jasper d. travertine
d
If water is the transport mechanism of sediment, the grain size of sedimentary deposits most closely indicates the ________. geographic extent of the weathering source rock at outcrop average velocity of the water from the time of erosion until deposition c. velocity of the water at the moment the sediment settled to the bottom climate conditions at the time of deposition
velocity of the water at the moment the sediment settled to the bottom
The figure below shows a moving source of light with four stationary observers at different locations. Which observer will see red-shifted light from the moving source (arrow is pointing at figure D. Figure D is to the left. A is on top, B is to the right, and C is below)
B
A guyot is ________. a. an extinct oceanic hot-spot volcano that has subsided below sea level b. synonymous with the term hot spot c. an extinct oceanic hot-spot volcano that has not yet subsided below sea level d. any portion of the ocean floor that is topographically higher than surrounding sea floor
a
A heavy book is placed on top of a ball of pizza dough, causing the dough to flatten. This is an application of ________. normal stress pressure shear stress metasomatism
a
A massive flood would be an example of a _________ change. a. catastrophic b. gradual c. unidirectional d. cyclic
a
A runaway greenhouse effect is an example of ________. a. a positive feedback mechanism b. a negative feedback mechanism c. the hydrologic cycle d. a steady-state condition
a
According to the model proposed by geophysicist J. Tuzo Wilson, hot spots are caused by ________. a. hot plumes of mantle material that rise up through cooler, denser surrounding rock b. unusually dense concentrations of radioactive isotopes at various points in the crust c. zones of localized subduction that produce melting of the mantle d. friction due to the lithosphere sliding atop the asthenosphere
a
Aside from Earth, the terrestrial planets are ________. a.Mars, Mercury, and Venus b.Mars, Venus, and Jupiter c.Jupiter, Saturn, Uranus, and Neptune d. Mars and Saturn
a
At a subduction zone, the downgoing (subducting) plate ________. a. is always composed of oceanic lithosphere b. may be composed of either oceanic or continental lithosphere c. is composed entirely of asthenosphere d. is always composed of continental lithosphere
a
Buried erosional surfaces between parallel sedimentary strata are termed ________. a. disconformities b. angular unconformities c. nonconformities d. marker beds
a
Cemented shells of marine organisms form which kind of sedimentary rock? a. biochemical b. chemical c. clastic d. organic
a
Clastic sedimentary rocks are primarily classified on the basis of ________. grain size degree of sorting angularity mineral composition
a
Cleavage in minerals refers to ________. a. a tendency to break along planes of weakness b. the sharpness of edges between crystal faces c. the development of well-formed crystal faces d. a tendency to break in an irregular pattern
a
Continental coastlines that occur within the interior of a tectonic plate are called ________ margins. a. passive b. inert c. internal d. active
a
Continental lithosphere ________. a. is thicker than oceanic lithosphere b. contains more mafic rocks than oceanic lithosphere c. contains no crustal material, consisting solely of lithified upper mantle d. is denser than oceanic lithosphere
a
Diamonds are usually found in pipes 50 to 200 m across made of ________. a. kimberlite b. metamorphic rocks c. sedimentary rocks d. graphite
a
Dissolution occurs when ________. a. minerals are dissolved into water b. minerals are turned into rust c. minerals absorb water and expand d. minerals are removed by frost
a
Eratosthenes was the first person to accurately estimate the size of Earth. He accomplished this feat by ________. a. observing shadows simultaneously cast at two different cities that were separated by a known distance b. sailing around the world and estimating his average rate of travel c. measuring the severity of the greatest earthquakes d. comparing the length of an Earth day with the distance between the Earth and the Sun
a
Geologists call individual layers of sedimentary rocks ________, whereas several of them together are called ________. a. beds; strata b. strata; beds c. laminations; graded beds d. graded beds; laminations
a
Hot-spot tracks result from moving ________. a. plates b. mantle plumes c. hot spots d. asthenosphere
a
How are carbon dioxide (CO2) levels in the atmosphere affected by tectonic uplift of rocks and their resultant chemical weathering? a. CO2 is removed from the atmosphere. b. CO2 is added to the atmosphere. c. CO2 is removed from the atmosphere by uplift, but returned to the atmosphere by chemical weathering. d. They have no net effect on CO2.
a
How is the half-life of a radioactive parent isotope defined? ta. he time it takes for half of the parent isotope to decay to daughter isotope b. half the time it takes for the parent isotope to completely decay c. the time it takes the parent isotope to go through half the decay steps necessary to produce a stable daughter isotope d. half of the average rate of decay of the parent isotope
a
If a geologist found preserved mud cracks, he or she could conclude that the environment in which they formed ________. a. was once covered in wet mud b. was once covered by a glacier c. has been subjected to a major climate change event d. was the site of a mass extinction event
a
If a rock is melted, then erupted at the surface and cooled, then eroded and deposited, what two rock types are involved in the sequence? a. igneous and sedimentary b. igneous and metamorphic c. sandstone and gneiss d. slate and granite
a
If a sandstone lies on top of a shale, ________. a. the shale must be older, according to the principle of superposition b. the sandstone must be older, according to the principle of superposition c. the shale must be older, according to the principle of components d. their relative ages cannot be determined from the information given
a
If an igneous dike cuts across a sequence of sedimentary beds, ________. a. the beds must be older b. the dike must be older c. the beds and the dike must have formed at the same time d. their relative ages cannot be determined from the information given
a
If water is the transport mechanism of sediment, the grain size of sedimentary deposits most closely indicates the ________. a. velocity of the water at the moment the sediment settled to the bottom b. geographic extent of the weathering source rock at outcrop c. climate conditions at the time of deposition d. average velocity of the water from the time of erosion until deposition
a
In the heliocentric model ________. a. Earth orbits around the Sun b. the Sun orbits around Earth c. Earth is a stationary planet d. Mercury and Venus orbit around the Sun, but all other planets orbit around Earth
a
Large, thick-crusted, nonvolcanic mountain belts, like the Himalayas, are associated with ________. a. continent-continent collisions b. hot spots c. subduction zones d. mid-ocean ridges
a
Limestone is most likely formed in which of the following environments? a. shallow-marine carbonate b. shallow-marine clastic c. deep marine d. marine delta
a
Minerals that do not possess cleavage are said to possess ________. a. fracture b. solidity c. massiveness d. invulnerability
a
Ore minerals, such as galena and hematite, tend to be different from typical minerals in that they have a ________. a. large specific gravity b. diamond-like crystal habit c. very dark color d. vitreous luster
a
Our Sun belongs to a galaxy known as ________. a. the Milky Way b. Cepheus c.the Stratosphere dAndromeda
a
Precipitation of gypsum due to evaporation of seawater produces which kind of sedimentary rock? a.chemical b. biochemical c. organic d. clastic
a
Pyrite (FeS2) is in which mineral class? a. sulfides b. carbonates c. oxides d. silicates
a
Siltstone or mudstone containing marine fossils likely formed in a ________ environment. a. shallow-marine b. deep-marine c. marine-delta d. coastal-beach
a
Stratification refers to ________. a. the development of layering within sedimentary rocks b. the act of deposition of sediment that will ultimately form sedimentary rock c. physical and chemical alterations, including compaction and cementation, that occur as sediment is transformed into rock d. the process of breaking down a source rock into smaller pieces called grains
a
Summed over the entire surface of Earth, the rate of spreading at divergent boundaries is ________ lithospheric consumption at subduction zones. a. equal to b. faster than c. This cannot yet be measured by geologists. d. slower than
a
Tectonic plates move at rates that are approximately ________. a. 1 to 15 cm/year b. 10 to 100 m/year c. 1 to 5 cm every 1,000 years d. 1 to 15 m/year
a
The amount of solar energy reflected by a surface is known as ________. a. Albedo b. radiation c. the reflection coefficient d. the absorption coefficient
a
The color of a mineral in powdered form is termed ________. a. streak b. luster c. color d. specific gravity
a
The hydrologic cycle includes which of these? a. the advance and retreat of glaciers b. the accumulation of methane in the atmosphere c. the secretion of carbonate shells by marine organisms d. photosynthesis
a
The lithosphere lies directly above the ________. a. asthenosphere b. crust c. transition zone d. lower mantle
a
The mid-ocean ridges are elevated above the surrounding sea floor because ________. a. ridge rocks are hot and therefore have relatively low density b. the lithosphere is thickest at the ridges so they stand up taller c. rising ocean currents create a vacuum that pulls ridges up d. ridge rocks are mafic, which are less dense than ultramafic ocean basin rock
a
The oceanic lithosphere is typically coated in a layer of sediment. Which of the following is NOT true about this sediment? a. All of the sediment is eventually subducted along with the lithosphere into the mantle. b. Some of the sediment may be scraped off at subduction zones by the overriding plate forming an accretionary prism. c. The layer of sediment is generally very thin or nonexistent at mid-ocean ridges. d. The layer of sediment is generally thicker on older oceanic lithosphere.
a
The shape of Earth's magnetic field is approximately that of a ________. a. dipole, such as that produced by a bar magnet b. sphere, following the shape of Earth c. torus, a doughnut-shaped ring parallel to Earth's equator d. monopole, as would be produced by just one pole of a magnet
a
Trace amounts of impurity in a mineral can commonly produce significant differences in ________ among individual crystals of this mineral. a. color b. streak c. luster d. cleavage
a
Under the theory of plate tectonics, the plates themselves are ________. a. discrete pieces of lithosphere at the surface of the solid Earth that move with respect to one another b. very thick (approximately one-quarter of Earth's radius) c. discrete layers of lithosphere that are vertically stacked one atop the other d. composed only of continental rocks that plow through the weaker oceanic rocks
a
What is the rock cycle? a. the transformation of one rock type to another b. the cycle that rocks undergo when interacting with air c. the transformation of one mineral type to another d. the cycle that rocks go through when interacting with water
a
What type of sediment is typically found in lake bottoms? a. clay/mud b. gravel c. silt d. sand
a
Which greenhouse gas has the greatest total importance in retaining radiant energy from the Earth? a. CO2 (carbon dioxide) b. O3 (ozone) c. NO2 (nitrous oxide) d. H2O (water)
a
Which of the following choices has particles ordered from smallest to largest in size? a. electron, proton, nucleus, atom b. atom, electron, nucleus, proton c. atom, nucleus, proton, electron d. proton, electron, nucleus, atom
a
Which of the following describes the progression of rock types through increasing metamorphic grade? a. shale Ò slate Ò phyllite Ò schist b. basalt Ò andesite Ò rhyolite Ò granite c. sandstone Ò gneiss Ò hornfels Ò zeolite d. migmatite Ò slate Ò eclogite Ò schist
a
Which of the following is NOT a mineral? a. petroleum b. diamond c. quartz d. gold
a
Which of the following is NOT a way for minerals to crystallize? a. bonding carbon to oxygen atoms to form organic compounds b. biomineralization c. solidification of a melt (lava/magma) d. solid-state diffusion
a
Which of the following is NOT part of the process that leads to the exhumation of metamorphic rocks? a. continents squeezing together mountain belts collapsing erosion d. rising plumes of magma in the mantle
a
Which of the following is a type of physical weathering? thermal expansion dissolution oxidation hydration
a
Which of the following minerals is more commonly known as table salt? a. halite b. feldspar c. quartz d. gypsum
a
Which transport medium carries the largest particles? a. ice in glaciers b. water in rivers c. wind d. water in lakes
a
Why do geologists classify rocks? a. because rocks are the key to determining how the Earth formed b. to determine the chemical makeup of the Earth c. so that they can tell how old the rock is d. because it makes it easier to tell them apart
a
With regard to minerals, hardness refers to the ability to resist ________. a. being scratched b. bending c. chemical reactions with other substances d. breaking
a
Glacial till is composed of ________-sized particles. mud sand boulder a mix of anything from mud to boulder
a mix of anything from mud to boulder
A fine-grained clastic sedimentary rock that splits into thin sheets is ________. a. arkose b. shale c. sandstone d. mudstone
b
According to Archimedes' principle of buoyancy, an iceberg sinks until ________. a. the total mass of the iceberg is underwater b. the total mass of the water displaced equals the total mass of the whole iceberg c. the total mass of the water displaced equals 80% of the mass of the iceberg d. about 60% of the iceberg is underwater
b
According to the Big Bang theory, our Universe is ________. a. contracting b. expanding c. static d. periodically contracting and expanding
b
Basaltic clasts within a conglomerate have been radiometrically dated to 50 million years ago. Is this a reliable age for the conglomerate? a. Yes. b. No, this age is likely too old. c. No, this age is likely too young. d. No, basalt never contains minerals bearing radioactive isotopes.
b
Beach sediments travel ________ the ocean during a transgression and ________ the ocean during a regression. a. toward; away from b. away from; toward c. parallel to; perpendicular to d. perpendicular to; parallel to
b
Broad, sediment-covered continental shelves are found along ________. a. deep-sea trenches b. passive margins c. active margins d. mid-ocean ridges
b
Compaction and cementation of grains occurs during ________. a. erosion b. lithification c. transport d. weathering
b
Earth's geothermal gradient is the rate of temperature change incurred by ________. a. increasing depth at ocean trenches b. traversing down within Earth's interior c. traversing from either pole toward the equator d. increasing altitude in the atmosphere
b
Earthquakes occur most frequently near ________ margins. a. passive b. active c. aseismic d. seismic
b
How are greenhouse gases like carbon dioxide and methane different from other atmospheric gases like nitrogen and oxygen? a. Greenhouse gases absorb thermal energy from the Sun and reradiate it, whereas other atmospheric gases reflect it. b. Greenhouse gases are more efficient at absorbing thermal energy and reradiating it than the other atmospheric gases. c. Greenhouse gases are found at higher levels of the atmosphere, where ozone is found. d. Greenhouse gases are found at lower levels of the atmosphere, where ozone is found.
b
How are pollen species used to interpret ancient environments? a. Each plant species is found in many different climates. b. Different plant species live in different climates. c. The ratio of oxygen isotopes can be measured in pollen. d. Specific plant species directly track the carbon dioxide concentration in the atmosphere
b
How does the formation of oil shale deposits, coals, and limestones affect the carbon dioxide (CO2) concentration in the Earth's atmosphere? a. All three increase the total CO2 in the atmosphere. b. All three decrease the total CO2 in the atmosphere. c. The formation of limestones decreases total CO2, while the formation of oil shale and coal increases total CO2. d. The formation of oil shale deposits, coals, and limestones has very little effect.
b
How does water get from the atmosphere into the groundwater system? a. Precipitation falls into rivers and then flows downriver into the groundwater system. b. Precipitation falls on the ground and infiltrates the ground surface to the groundwater system. c. Water from the ocean is sucked up into the groundwater system due to a pressure difference. d. Plants secrete water into the groundwater system in a process called evapotranspiration.
b
If horizontal sedimentary strata overlie tilted strata (and no fault is present), the surface between the horizontal and tilted strata must be a(n) ________. conformable sedimentary contact b. angular unconformity disconformity nonconformity
b
In ancient Greece, Eratosthenes measured the difference in angles of the Sun's rays in two different locations in Egypt at the same time to calculate the ________. a. distance from the Earth to the Moon b. circumference of the Earth c. rate of rotation of the Earth d. distance from Earth to the Sun
b
In the area immediately surrounding an igneous intrusion, a host limestone is locally metamorphosed to produce marble. Which of the following statements is correct? a. The intrusive igneous rock must be older than the limestone. b. The limestone must be older than the marble. c. The marble must be older than the intrusive rock. d. The relative ages of the three units cannot be determined with the information given.
b
In which type of silicate are the greatest proportion of oxygen atoms shared by pairs of adjacent tetrahedra? a. sheet silicates b. framework silicates c. Sharing of oxygen atoms does not occur in silicates. d. chain silicates
b
Increasing ratios of oxygen-18 to oxygen-16 in glacial ice indicate ________. a. advancing ice sheets b. warming temperatures c. increased volcanic emissions d. uplift of land surfaces
b
Milankovitch cycles describe variation in the Earth's ________. a. sea level b. orbit and tilt c. atmospheric carbon dioxide concentrations d. cosmic-ray flux
b
Oceanic lithosphere thickens away from the mid-ocean ridge primarily due to ________. a. the addition of new crust due to hot-spot volcanism b. the addition of new lithospheric mantle as a result of cooling c. the addition of new crust due to sedimentation d. reasons that geologists cannot determine at present
b
Of the ~4,000 known minerals, the vast majority ________. a. are quite common b. are rare c. form only near volcanoes d. are characterized as gems
b
Precipitation of gypsum due to evaporation of seawater produces which kind of sedimentary rock? a. biochemical b. chemical c. clastic d. organic
b
Relative ages expressed on the geologic time scale primarily resulted from the study of ________. a. fossil content and spatial relationships among igneous rocks b. fossil content and spatial relationships among sedimentary rocks c. radiometric dating of igneous rocks d. radiometric dating of sedimentary rocks
b
Salt water is the end product of this weathering process. a. hydrolysis dissolution jointing frost wedging
b
Sedimentary sequences, which are bounded by unconformities, record global sea level rise and fall with variations in ________. a. fossil content b. the coarseness of clastic sediments/sedimentary rocks c. carbon content d. coal grade
b
Slab pull occurs because subducting slabs are ________. a. hotter, and therefore more dense, than surrounding asthenosphere b. cooler, and therefore more dense, than surrounding asthenosphere c. less mafic, and therefore less dense, than surrounding asthenosphere d. cooler, and therefore less dense, than surrounding asthenosphere
b
Summed over the entire surface of Earth, the rate of spreading at divergent boundaries is ________ lithospheric consumption at subduction zones. a. faster than b. equal to c. This cannot yet be measured by geologists. d. slower than
b
The Dust Bowl of the 1930s was created by what phenomenon? increased rainfall b. lack of vegetation increased wind storms differential weathering Question 19
b
The Moho ________. a. is found deeper underneath oceans than under continents b. is found deeper underneath continents than under oceans c. lies at uniform depth everywhere it is found in Earth d. is found well below the crust/mantle boundary
b
The application of ________ during metamorphism causes elongated crystals to align parallel with each other. When this happens, the rock develops ________. a. pressure; a homogeneous texture b. differential stress; foliation c. high temperatures; foliation d. pressure; foliation
b
The lithosphere of Earth will not flow because it ________. a. is too old b. is too cool c. contains radioactive elements d. is too dense
b
The majority of the rocks that occur at the surface of Earth are ________. a. extrusive igneous rocks b. sedimentary rocks c. metamorphic rocks d. intrusive igneous rocks
b
The primary cause of recent global warming is believed to be ________. a. chemical reactions in the atmosphere that are driven by solar heat b. increased burning of fossil fuels c. increased levels of atmospheric pollution d. depletion of the ozone layer
b
The primary difference between lithospheric and asthenospheric mantle that gives rise to numerous different patterns of physical behavior is ________. a. chemical composition: the lithosphere is felsic; the asthenosphere is mafic b. temperature: the lithosphere is cooler than the asthenosphere c. physical state: the lithosphere is solid; the asthenosphere is liquid d. chemical composition: the lithosphere is mafic; the asthenosphere is felsic
b
The rate of motion of a lithospheric plate with respect to a stationary location inside the Earth is termed ________, while the motion of a plate with respect to another is termed ________. a. Both are measures of absolute velocity. b. absolute plate velocity; relative plate velocity c. Both are measures of relative velocity. d. relative plate velocity; absolute plate velocity
b
The ratio of oxygen-16 and oxygen-18 isotopes in plankton fossils in deep-sea sediments can be used to determine ________. a. past carbon dioxide concentrations b. past temperatures c. the age of the fossils d. water depth
b
The removal of detritus from weathered rock at an outcrop is termed ________. a. deposition b. erosion c. weathering d. lithification
b
The thickness of oceanic lithosphere is ________. a. nearly uniformly 100 km b. least near the mid-ocean ridges and thickens away from the ridges c. greatest at the geographic poles and least near the equator d. greatest near the mid-ocean ridges and thins out away from the ridges
b
The volcanoes of the Cascades Mountains in the northwest United States are related to melting of rock associated with a ________. a. divergent plate boundary b. convergent plate boundary c. hot spot d. transform plate boundary
b
Thermal (contact) metamorphism produces ________. a. foliated rocks only b. nonfoliated rocks only c. both foliated and nonfoliated rocks d. Thermal metamorphism does not produce any metamorphic rocks.
b
Uniformitarianism is succinctly summarized by which phrase? a. The future is the key to the present. b. The present is the key to the past. c. The past is the key to the present. d. The present is the key to the future.
b
What is the difference between weather and climate? a. Weather is a long-term cycle, whereas climate is a transient condition. b. Weather is a transient condition, whereas climate is a long-term cycle. c. Weather relates to precipitation, whereas climate relates to temperature. d. The two terms are essentially interchangeable.
b
What process must occur for an igneous rock to turn into a sedimentary rock? a. metamorphism b. erosion c. melting d. petrogenesis
b
What type of weathering are you likely to find occurring in areas with cold climates? a. hydrolysis b. frost wedging c. salt wedging d. dissolution
b
When a solution becomes oversaturated, new solid particles are said to ________. a. react with the solution and produce heat b. precipitate from the solution c. dissolve into the solution d. rapidly expand, causing an explosion
b
When an unstable parent isotope decays, which of these is true? a. The daughter isotope will be a stable isotope. b. The daughter isotope may continue to decay. c. The parent isotope's rate of decay slows. d. The parent isotope becomes stable and stops decaying.
b
Which method of correlation is most reliable for determining age equivalence among bodies of rock that are physically separated by vast distances? lithologic correlation fossil correlation inclusion correlation unconformity correlation
b
Which mineral is integral to paleomagnestim? a. potassium feldspar b. magnetite c. quartz d. iron
b
Which of the following common minerals is hardest? a. fluorite b. quartz c. talc d. calcite
b
Which of the following common minerals is softest? a. calcite b. talc c. quartz d. fluorite
b
Which of the following does NOT affect soil thickness? time types of animals climate vegetation type
b
Which of the following geologic principles is NOT a result of gravity? a. original horizontality b. cross-cutting relationships c. original continuity d. superposition
b
Which of the following is NOT one of the three major rock groups? a. igneous b. crystalline c. sedimentary d. metamorphic
b
Which of the following is NOT true about regressions? a. They are not typically well preserved in the sedimentary record. b. They can occur when the climate warms and continental ice sheets melt. c. They occur when the land is uplifted by tectonic processes. d. Coastal environments will migrate seaward.
b
Which of the following is a mineral? a. cubic zirconia, which is a synthetic diamond substitute b. ice, which is water in the solid state c. petroleum (oil), which is a liquid d. obsidian, a type of volcanic glass
b
Which of the following statements is true concerning rock produced at mid-ocean ridges? a. All of the rock produced is gabbro. b. Basalt is produced at shallow depths and gabbro at deeper depths. c. All of the rock produced is basalt. d. Gabbro is produced at shallow depths and basalt at deeper depths.
b
Which of these parts of the deep-ocean floor is flat and nearly featureless? a. trench b. abyssal plain c. guyot d. ridge axis
b
Why does physical weathering speed up the processes of chemical weathering? a. Physical weathering requires abundant water, as does chemical weathering. b. Physical weathering produces fresh surfaces for chemical weathering to attack. c. Chemical weathering can occur only on small surfaces, not large ones. d. Chemical weathering requires salt, which is provided by salt wedging.
b
With increasing distance from a mid-ocean ridge, the age of oceanic crust ________. a. stays constant b. increases c. varies randomly d. decreases
b
________ commonly serves as a protolith in the formation of quartzite. a. Limestone b. Sandstone c. Shale d. Slate
b
Which environment would most likely produce sedimentary deposits characterized by very well-sorted, very well-rounded grains that are nearly pure quartz? a. river b.beach c.glacier d. alluvial fan
b. beach
A blogger writes that global warming is not real, noting that his or her city had its coldest ever-recorded temperature last winter. The correct statement would be that the blogger is ________. a. correct, because global warming is not occurring b. correct, because global warming is occurring only in the polar regions c. incorrect, because the blogger is confusing weather with climate d. incorrect, because global warming is measured only during the summer
c
A buried body of shale is subjected to differential stress, causing clay minerals to realign and produce slate. This is an example of ________. diagenesis erosion metamorphism weathering
c
A volcanic island arc forms when ________. a. two plates of continental lithosphere collide b. continental lithosphere subducts beneath oceanic lithosphere c. oceanic lithosphere subducts beneath another oceanic lithospheric plate d. oceanic lithosphere subducts beneath continental lithosphere
c
As understood by modern geologists, the principle of uniformitarianism implies that ________. a. the Earth has always had the same basic appearance that it has today b. igneous, metamorphic, and sedimentary rocks are uniformly mixed throughout the crust c. physical processes observed today (such as erosion and volcanic eruption) have been active in the past and are preserved in the rock record d. physical processes observed today (such as erosion and volcanic eruption) have been occurring throughout Earth history at constant rates
c
At transform plate boundaries, ________. a. both earthquakes and volcanoes are common b. volcanoes are common but earthquakes do not occur c. earthquakes are common but volcanoes are absent d. neither earthquakes nor volcanoes are common
c
Compared to oceanic crust, continental crust is ________. a. thinner b.about the same thickness c. thicker d. Sometimes continental crust is thicker; sometimes oceanic crust is thicker. There is no consistent pattern.
c
Deformed (bent, stretched, or cracked) lithosphere occurs ________. a. randomly over the surface of Earth b. primarily at hot spots c. primarily on the margins of tectonic plates d. primarily within the interiors of tectonic plates
c
Diagenesis refers to ________. a. the development of layering within sedimentary rocks b. the act of deposition of sediment that will ultimately form sedimentary rock c. physical and chemical alterations, including compaction and cementation, that occur as sediment is transformed into rock d. the natural process of separating sediment by grain size
c
Differential weathering occurs when ________. a. none of the layers weather at all b. layers of rock weather at the same rate c. layers of rock weather at different rates d. weathering occurs in the tropics
c
Distinctive rock sequences on South America terminate at the Atlantic Ocean but reappear on the continent of ________. a. Europe b. North America c. Africa d. Australia
c
During a journey to the center of the Earth, one would experience temperature ________. a. remaining remarkably constant, but pressure increasing b. and pressure both decreasing c. and pressure both increasing d. increasing, but pressure staying nearly the same
c
During most of the Mesozoic Era, the Earth was ________. a. about as warm as present b. cooler than present c. warmer than present d. experiencing wild temperature fluctuations
c
Earth's magnetic field is generated by the ________. a. magnetic minerals within the crust b. flow of the liquid inner core c. flow of the liquid outer core d. convective flow of the mantle
c
For the majority of minerals, the streak color obtained when the mineral is scratched against a porcelain plate is ________. a. always dark brown or black b. more variable than the color in a hand sample among crystals c. only useful if the mineral is softer than porcelain d. not useful because the porcelain will often chemically react with the mineral
c
Grains become rounded primarily during ________. a. lithification b. deposition c. transportation d. weathering at the outcrop
c
Hot spots can occur ________. a. only within oceanic plates b. only when the thickness of the crust is less than 10 km c. within either continental or oceanic plates d. only within continental plates
c
How much of a radioactive parent isotope will remain after three half-lives have passed? a. one-third b. three-halves c. one-eighth d. one-sixth
c
How would you tell if a rock is crystalline? a. It does not contain crystals at all. b. It contains all one type of crystal. c. It contains interlocking crystals. d. It contains crystals that have been cemented together.
c
Igneous rocks form from ________. a. sediments cemented together b. heat and pressure applied to a rock c. molten rock cooling and forming crystals d. precipitation of minerals out of a solution
c
In a hot-spot volcanic island chain, such as the Hawaiian Islands, which of the following is NOT true? a. The magma source stays approximately fixed, but motion of the overriding plate forms a hot-spot track. b. The presence of volcanism is not related to a plate boundary. c. All volcanoes in the chain can be simultaneously active. d. The ages and distance between volcanoes can be used to calculate plate velocities.
c
In the last few decades, global warming has been most strongly affecting climate and wildlife of ________ regions. a. equatorial b. temperate c. polar d. deep-sea
c
In the scope of plate tectonics, an active margin is defined as ________. a. anywhere on Earth where earthquakes are especially frequent b. a five-mile radius surrounding an active volcano c. a continental coastline that coincides with a plate boundary d. synonymous with "subduction zone"
c
It is unusual for ________ to carry grains larger than sand. a. ice in glaciers b. water in rivers c. wind d. water at a seaside beach
c
Lithified detritus (breakdown products of preexisting rocks) forms which kind of sedimentary rock? a. biochemical b. chemical c. clastic d. organic
c
Magnetostratigraphy takes advantage of the fact that Earth's magnetic field ________. a. only arose 10,000 years ago b. has been uniformly strong, with constant polarity, throughout Earth's history c. has experienced numerous polarity reversals, with periods of normal and reversed polarity of varying lengths d. has experienced numerous regular, predictable polarity reversals
c
Mid-ocean ridges are segmented and contain which two basic types of plate boundaries linked together? a. divergent and convergent b. convergent and transform c. divergent and transform d. conformal and transvergent
c
Minerals are grouped into mineral classes primarily on a basis of ________. a. chemistry, specifically the cations within the chemical formula b. hardness; hard, soft, and medium are the three primary classes c. chemistry, specifically the anions within the chemical formula d. the number of cleavage directions present
c
Models used by the Intergovernmental Panel on Climate Change show that by the year 2100, the average annual temperature will have increased in some parts of the world by as much as ________. a. 1°C b. 2°C c. 4°C d. 8°C
c
Most of the pushing force driving plate motion is produced ________. a. in the interiors of continental plates b. at subduction zones c. at mid-ocean ridges d. at collision zones
c
Natural carbon sinks have generally matched the production of carbon dioxide until ________. a. the end of the last ice age, approximately 16,000 years ago b. the Little Ice Age, approximately 400 years ago c. approximately 1900 d. the Eocene Epoch, approximately 50 million years ago
c
Numerical ages for boundaries between time units on the geologic time scale primarily resulted from the study of ________, in conjunction with relative age data. a. fossil content and spatial relationships among igneous rocks b. fossil content and spatial relationships among sedimentary rocks c. radiometric dating of igneous rocks d. radiometric dating of sedimentary rocks
c
On either side of a mid-ocean ridge, the lithosphere begins to ________. a. sink because convection pulls it downward b. rise because it becomes buoyant c. sink because it cools and contracts d. rise because it thickens away from the ridge
c
Potassium feldspar (KAlSi3O8) is in which mineral class? a. carbonates b. oxides c. silicates d. sulfides
c
Preexisting rock that is subsequently altered to form a metamorphic rock is termed a ________. a. xenolith b. source rock c. protolith d. phenocryst
c
Presently, Earth's atmosphere is dominated by which two gases? a. hydrogen and helium b. oxygen and carbon dioxide c. nitrogen and oxygen d. carbon dioxide and sulfur dioxide
c
Sea level rises locally, and marine sediments are deposited on top of terrestrial sediments during events termed ________. a. turbidity currents b. cross bedding c. transgressions d. regressions
c
Seafloor spreading is driven by volcanic activity ________. a. at the edges of continental shelves b. in the middle of abyssal plains c. along mid-ocean ridges d. along fracture zones
c
Segments of mid-ocean ridge systems are offset. Between the offset segments we observe ________. a. deep-ocean trenches b. hot spots c. transform faults d. a second series of ridges, perpendicular to the main set
c
Some researchers think that ________ are causing a sixth mass-extinction event. a. the cosmic rays b. the tides c. humans d. asteroids
c
Stratification refers to ________. a. the process of breaking down a source rock into smaller pieces called grains b. physical and chemical alterations, including compaction and cementation, that occur as sediment is transformed into rock c. the development of layering within sedimentary rocks d. the act of deposition of sediment that will ultimately form sedimentary rock
c
Subduction zones are found at which basic plate boundary type? a. divergent b. transform c. convergent d. transvergent
c
Synthetically made glass and natural quartz crystals both exhibit a fracture pattern termed ________. a. one-directional cleavage b. obtuse fracture c. conchoidal fracture d. glassy fracture
c
Tectonic plates move at rates that are approximately ________. a. 1 to 5 cm every 1,000 years b. 10 to 100 m/year c. 1 to 15 cm/year d. 1 to 15 m/year
c
Terrestrial planets are mainly composed of ________ while Jovian planets are made dominantly of ________. a. volatiles; rock and metals b. volatiles and metals; refractory materials c. rock and metals; volatiles d. refractory materials; volatiles and metals
c
The San Andreas Fault zone in California is an example of a ________ plate boundary. a. divergent b. convergent c. transform d. transvergent
c
The breakdown of exposed rock into small fragments and dissolved ions is termed ________. deposition erosion weathering lithification
c
The circumference of Earth is most nearly ________. a.4,000 km b.400 km c. 40,000 km d. 4,000,000 km
c
The development of a preferred orientation of large, flaky mica crystals within metamorphic rock is termed ________. slaty cleavage phyllitic luster schistosity compositional banding
c
The evolution of the Earth's atmosphere has been a(n) __________. a. static condition b. Earth system c. unidirectional change d. cyclic change
c
The lithosphere is composed of the ________. a. crust, mantle, and outer core b. crust only c. crust and the uppermost part of the mantle d. top 100 m of sediments and sedimentary rocks
c
The majority of the rocks that occur at the surface of Earth are ________. intrusive igneous rocks extrusive igneous rocks sedimentary rocks metamorphic rocks
c
The mineral class that makes up >95% of the continental crust is termed the ________. a. halides b. oxides c. silicates d. carbonates
c
The reliable paleoclimate record from the Antarctic and Greenland ice cores provides information back to approximately ________ years ago. a. 65 million b. 5 million c. 800,000 d. 150,000
c
The sedimentary rocks breccia and conglomerate most commonly form in a ________ environment. a. beach b. lake c. mountain stream d. deep-ocean basin
c
The silica tetrahedron that forms the backbone of all the silicate minerals is composed of silicon and what other element? a. iron b. magnesium c. oxygen d. carbon
c
The single property that can be used to identify any mineral is ________. a. color b. luster c. Multiple properties must d. be used to identify a mineral. cleavage
c
The surface below sedimentary rocks that overlie igneous or metamorphic rocks is termed a(n) ________. disconformity angular unconformity nonconformity marker bed
c
The theory of plate tectonics ________. a. does not incorporate seafloor spreading or continental drift b. incorporates seafloor spreading but not continental drift c. incorporates and explains both seafloor spreading and continental drift d. incorporates continental drift but not seafloor spreading
c
The youngest sea floor is typically found ________. a. randomly within abyssal plains b. along passive margins c. along mid-ocean ridges d. along active margins
c
Two major sources of energy, coal and oil shale, are considered ________ sedimentary rocks. clastic biochemical organic chemical
c
Unlike the lithosphere, the asthenosphere ________. a. has a density similar to the core b. varies in thickness from place to place c. is able to flow over long periods of time d. is relatively cool
c
Volatile materials can exist as a gas at Earth's surface. Which of the following is NOT a volatile material? a. water b. hydrogen c. silicon d. carbon dioxide
c
What is a primary difference between phyllite and schist? a. Schist contains mica, whereas phyllite contains only clay. b. Phyllite contains mica, whereas schist contains only clay. c. Mica crystals within schist are larger than those within phyllite. d. Mica crystals within phyllite are larger than those within schist.
c
What type of weathering are you most likely to find occurring on the coast? dissolution thermal expansion salt wedging root wedging
c
When two plates composed of continental lithosphere are pulled together at a convergent boundary, the result is ________. a. subduction b. a hot spot is formed c. collision and mountain formation d. transform faulting
c
Where Earth's magnetic dipole intersects with the surface of the planet is called the ________. a. geographic pole b. magnetic inclination c. magnetic pole d. magnetic dipole
c
Which environment would most likely produce sedimentary deposits characterized by very well-sorted, very well-rounded grains that are nearly pure quartz? river glacier beach alluvial fan
c
Which of the following best explains how the carbon cycle plays a role in climate change? a. The carbon cycle influences the amount of moisture in the atmosphere, which influences climate. b. The amount of carbon dissolved in seawater influences ocean temperatures, and thus climate. c. Some carbon occurs in greenhouse gases, which influence climate. d. Carbon in the ozone layer reflects sunlight, which influences climate.
c
Which of the following geologic principles is a direct result of gravity? a. baked contacts b. cross-cutting relationships c. original horizontality d. inclusions
c
Which of the following is NOT true about minerals? a. Some minerals are precipitated by organisms. b. All minerals are naturally made. c. All minerals are compounds of more than one element. d. All minerals can be expressed as chemical formulas.
c
Which of the following is NOT true? Sediments deposited in a beach environment are typically ________. well sorted medium grained composed of angular grains composed of mostly quartz
c
Which of the following processes releases carbon dioxide into the atmosphere? a. photosynthesis b. the weathering of silicate rocks c. volcanism d. the burial of organic matter
c
Which type of weathering process is happening to materials when they rust? hydrolysis hydration oxidation dissolution
c
Why is radiocarbon dating only rarely applied in geological work? a. No substances on Earth contain significant amounts of carbon-14. b. The half-life of carbon-14 is so long that it is effectively a stable isotope. c. The half-life of carbon-14 is so short that it can only be used to date materials that are less than 70,000 years old. d. Carbon-14 is destroyed by the heat of magma.
c
Within the world's sedimentary rocks, fossils ________. are rarely, if ever, found are randomly distributed c. occur in an ordered sequence d. are found only in igneous rocks
c
________ commonly serves as a protolith in the formation of slate. Limestone Sandstone Shale Basalt
c
________ is a mineral property defined by the density of the mineral sample divided by the density of water (1.0 g/cm3). a. Streak b. Luster c. Specific gravity d. Mass
c
A basic history of global climate change is preserved in the stratigraphic record because... a. characteristics of igneous rocks depend on climate because of variations in cooling rates. b. the amount of sediment deposited is a function of climate. c. the amount of fossils preserved in the rock record is dependent on climate. d. depositional setting and the assemblages of organisms depend on the climate.
d
A clastic rock composed of sand-sized grains derived from the physical weathering of granite and containing a sizable proportion of feldspar is termed ________. a. metasandstone b. lithosandstone c. wacke d. arkose
d
According to Archimedes' principle of buoyancy, an iceberg sinks until ________. a. the total mass of the iceberg is underwater b. the total mass of the water displaced equals 80% of the mass of the iceberg c. about 60% of the iceberg is underwater d. the total mass of the water displaced equals the total mass of the whole iceberg
d
Accurate radiometric dating is possible only if a rock contains a measurable amount of ________. a. parent isotope atoms b. daughter isotope atoms c. either parent or daughter atoms d. both parent and daughter atoms
d
At a subduction zone, the overriding plate ________. a. is composed entirely of asthenosphere b. is always composed of continental lithosphere c. is always composed of oceanic lithosphere d. may be composed of either oceanic or continental lithosphere
d
Broadly, metamorphism involves ________. a. the settling of crystals in a melt as it cools b. the sorting of grains by size, as accomplished by rivers and beach waves c. the cementation of loose grains and the precipitation of new minerals into pore spaces d. changes in mineralogy and texture in response to heat and stress
d
Calcite (CaCO3) is in which mineral class? a. sulfides b. oxides c. silicates d. carbonates
d
Can the age of Earth be reliably estimated from sediment thicknesses? a. Yes: sedimentation rates remain constant at any one locality throughout Earth's history. b. Yes: sedimentary rocks are rarely metamorphosed or melted. c. No: sedimentary rocks make up only a small fraction of the rocks on Earth's surface. d. No: much of Earth's history is represented by unconformities between strata rather than the strata themselves.
d
Chemical weathering involves the breakdown of material due to ________. a. mechanical breakdown of rock b. baking in the hot sun c. interaction with molten rock d. interaction with water or air
d
Chemically precipitated limestone that forms in caves or around hot springs is termed ________. a. agate b. dolostone c. jasper d. travertine
d
Clastic sedimentary rocks are primarily classified on the basis of ________. a. degree of sorting b. angularity c. mineral composition d. grain size
d
Climate affects landscape development by controlling... a. the composition of the substrate. b. the amount of water available on the Earth. c. the resistance of the sediments deposited. d. the rate of erosion.
d
Compaction and cementation of grains occurs during ________. a.weathering b. erosion c. transport d. lithification
d
Compared to typical oceanic lithosphere, the thickness of continental lithosphere is________. a. approximately the same b. There is not a consistent pattern of lithospheric thickness. c. less d. greater
d
Deep-oceanic trenches are features of ________ plate boundaries. a. transform b. divergent c. transvergent d. convergent
d
Dendrochronology involves dating of historic and geologic events through the study of ________. a. growth layers in shells b. oxygen isotope profiles in glacial ice c. remnant magnetism in iron-rich minerals d. annual growth rings in trees
d
Earth's surface is protected from solar wind and cosmic radiation by ________. a. Earth's gravitational field b. a powerful stream of ions emitted by the Sun c.a large, metallic shield launched into orbit by NASA in the 1960s d. Earth's magnetic field
d
Iceland is one of the few places in the world that is both above sea level and situated atop a ________ plate boundary. a. convergent b. transform c. Iceland is not located at a plate boundary. d. divergent
d
If all of Earth's history were compressed into a single year, Homo sapiens would first appear on ________. a. February 26 (close to Mardi Gras) b. April 15 (just before taxes are due) c. October 31 (just in time for Halloween) d. December 31, at 11:59 P.M. (just before the ball drops on New Year's Eve)
d
If one were to ride a hot air balloon up into the atmosphere, one would experience the concentration of gases ________. a. becoming denser b. remaining the same c. increasing for the first 10 km, then starting to decline d. becoming less dense
d
If the climate in an area has very little rainfall, what would be the characteristics of the soil in the area? a. thick, with a lot of organic material b. thin, with a lot of organic material c. thick, with very little organic material d. thin, with very little organic material
d
In an unweathered sample of rock, the ratio of an unstable isotope to its stable daughter isotope is 1:15. If no daughters were present at the time the rock cooled below closure temperature, and the half-life of the isotope is 50 million years, how old is the rock? a. 200 million years b. 400 million years c. 750 million years d. 1 billion years
d
In silicate minerals, silica tetrahedra may be chemically bonded to form all of the following EXCEPT ________. a. flat two-dimensional sheets b. long one-dimensional chains c. complex three-dimensional frameworks d. nearly perfect pyramid-shaped crystals
d
James Hutton, the "father of geology," put forth the principle of ________. superposition original continuity original horizontality uniformitarianism
d
Lithified detritus (breakdown products of preexisting rocks) forms which kind of sedimentary rock? a.chemical b.organic c.biochemical d.clastic
d
Minerals are all naturally occurring solid substances with a definable chemical composition. They must also possess ________. a. an ability to be synthesized in the laboratory as well as be found in nature b. metallic elements, such as iron, calcium, or magnesium c. metallic luster d. a fixed crystalline structure (spatial arrangement of atoms and ions)
d
Minerals utilized by humans as a source of metal are termed ________ minerals. a. metallic b. industrial c. source d. ore
d
Natural glass is NOT considered a mineral because it ________. a. is not produced by geologic processes b. can be made synthetically as well as be a naturally occurring substance c. is organic d. does not have a fixed crystalline structure
d
Potassium feldspar reacts with water to form clay. This is an example of ________. a. diagenesis b. erosion c. metamorphism d. weathering
d
Regional metamorphism ________. a. takes place at cool temperatures and low pressure b. takes place at cool temperatures but high pressure c. is another name for thermal metamorphism d. is another name for dynamothermal metamorphism
d
Short-term cycles of sea level rise and fall often create sedimentary sequences with sandstone at the base, grading up into coal. These cycles are called ________. a. geotherms b. Cross-bedding c. bathycycles d. cyclothems
d
The blueschist facies is a metamorphic realm of ________. a. high temperature and pressure b. low temperature and pressure c. high temperature but relatively low pressure d. high pressure but relatively low temperature
d
The cycle of supercontinent formation and breakup is an example of _________ change. a. catastrophic, unidirectional b. gradual, unidirectional c. catastrophic, cyclic d. gradual, cyclic
d
The lithosphere of the Earth is generally thickest at and near ________ plate boundaries. a. transform b. divergent c. transvergent d. convergent
d
The lithosphere of the Earth is generally thinnest at ________ plate boundaries. a. convergent b. transvergent c. transform d. divergent
d
The mineral assemblage within metamorphic rock is ________. a. always identical to that found within its protolith b. dependent only on the mineral assemblage of its protolith c. dependent only on the temperature and pressure of formation d. dependent on both the mineral content of its protolith and the temperature and pressure of formation
d
The most recently formed portion of any crystal is always found ________. a. deep within the interior b. There is no consistent pattern for crystal formation. c. on whichever side is currently facing upward d. on the outer edges
d
The primary difference between breccia and conglomerate is that conglomerate ________. a. is finer grained than breccia b. is coarser grained than breccia c. possesses more angular grains than breccia d. possesses more rounded grains than breccia
d
The warmest global temperatures since the last ice age occurred in the ________. a. recent period of human-induced global warming b. Younger Dryas, approximately 13,000 years ago c. Little Ice Age, approximately 400 years ago d. Holocene Maximum, approximately 6,000 years ago
d
The way a mineral scatters light is a useful diagnostic property termed ________. a. reflectivity b. color c. streak d. luster
d
Two major sources of energy, coal and oil shale, are considered ________ sedimentary rocks. a. chemical b. clastic c. biochemical d. organic
d
What type of rock is formed after erosion, deposition, and lithification? a. metamorphic b. crystalline c. igneous d. sedimentary
d
What type of sediment is typically found in lake bottoms? a. gravel b. sand c. silt d. clay/mud
d
Which common gemstone results from biomineralization? a. diamond b. garnet c. sapphire d. pearl
d
Which environment would most likely produce sedimentary deposits characterized by poorly to moderately sorted, angular to subangular grains that consist of feldspar, quartz, and lithics (rock fragments)? river glacier beach alluvial fan
d
Which greenhouse gases play the most significant role in influencing changes in global atmospheric temperature? a. carbon dioxide and ozone b. nitrogen dioxide and ozone c. nitrogen dioxide and methane d. carbon dioxide and methane
d
Which of the following best describes the hydrologic cycle? a. the movement of water through the ground to form aquifers b. the cycle that water passes through when going from solid to liquid to gas c. the circular motion due to density differences created when water boils d. the movement of the Earth's water through a series of reservoirs
d
Which of the following is NOT true about Earth's tectonic plates? a. Some tectonic plates contain only oceanic lithosphere. b. Some tectonic plates contain both oceanic and continental lithosphere. c. Tectonic plates vary greatly in size. d. Some tectonic plates contain only continental lithosphere.
d
Which of the following is NOT true concerning the color of minerals? a. The streak color tends to be less variable than the color of a whole mineral. b. Some minerals have a consistent color, but many have a range of possible colors. c. Color is often controlled by impurities or minor chemical components of the mineral. d. A mineral's color reflects the wavelengths of light that are absorbed by the mineral.
d
Which of the following processes CANNOT occur in the formation of metamorphic rock? a. the realignment of minerals so that they develop a preferred orientation b. the segregation of minerals into layers of different compositions c. the solid-state rearrangement of atoms or ions to create a new assemblage of minerals d. complete remelting of the rock, followed by solidification to form a new rock
d
Which of the following would NOT be considered a rock? a. a natural material composed of interlocking crystals b. a natural material made of frothy glass c. a natural material made of shells cemented together d. a natural pile of unconsolidated sand
d
Which of these is the longest-lasting sink for carbon dioxide? a. plant tissues and cellulose (the "woody" parts of plants) b. the atmosphere c. air bubbles within glacial ice d. limestones
d
Which process removes carbon dioxide from the atmosphere? a. respiration (breathing) of animals b. burning of coal and other fossil fuels c. volcanism d. photosynthesis
d
With the increased data collected in recent years, scientists have become increasingly certain that the Earth's climate is ________. a. not warming because carbon dioxide levels are decreasing b. not warming because the Sun's activity is at a minimum c. warming solely as a result of increased solar output d. warming as a result of human inputs of atmospheric greenhouse gases
d
Within a single mountain range, ________. a. only low-grade metamorphic rocks are likely to be found b. only high-grade metamorphic rocks are likely to be found c. only nonfoliated metamorphic rocks are likely to be found d. it is possible to find a variety of metamorphic rocks produced in distinct facies, including high-, intermediate-, and low-grade rocks Question 141 / 1 point
d
If a geologist found preserved mud cracks, he or she could conclude that the environment in which they formed ________. a. was once covered by a glacier b. was the site of a mass extinction event c. has been subjected to a major climate change event d. was once covered in wet mud
d.
Which of the following best describes the Earth's climate history? a. The Earth's climate has remained consistent with time. b. Most of the Earth's climate history has been significantly colder than it is currently. c. Most of the Earth's climate history has been significantly warmer than it is currently. d. Temperatures on the Earth have varied throughout geologic time.
d.
Which transport medium carries the largest particles? a.water in lakes b.wind c.water in rivers d. ice in glaciers
d. ice in glaciers
Which soil horizon contains the most organic material? A O B E
o