GEO 101 Exam 1
All of the following criteria define a mineral except? a. it is organic b. it is inorganic c. it has an orderly internal structure d. it is naturally occurring e. it has a well-defined chemical composition
A
How are felsic magmas formed? a. heat from the mantle melts part of the lower crust b. felsic magmas form when volcanoes mix mafic rock with dissolved gases c. felsic magmas generally do not exist d. pressure from overlying crust forces mantle magmas through cracks to Earth's surface
A
How does water content of melt change with increasing pressure? a. water content increases with increasing pressure b. water content remains the same with increasing pressure c. water content decreases with increasing pressure
A
Name two minerals that are unlikely to coexist in the same igneous rock. a. muscovite and pyroxene b. na-plagioclase and amphiboles c. pyroxene and olivine d. quartz and muscovite e. quarts and feldspar
A
Quartz exhibits (blank). a. conchoidal fracture b. four sets of cleavage at non-90 degree angles c. thin, transparent sheets that are easily separable d. three sets of cleavage at 90 degree angles e. a cubic shape
A
The amount or quality of light that is reflected from a mineral surface is known as (blank)? a. luster b. crystallization c. color d. streak e. transparency
A
The micas (biotite and muscovite) exhibit what type of silicate structure? a. sheet b. single chain c. 3D d. independent e. double chain
A
What are composite volcanoes made of? a. pyroclastic deposits b. pyrobasalt deposits c. basalt flows d. granite flows
A
What causes vesicles to form in lava? a. trapped gas bubbles b. large crystal formation due to slow cooling c. a turbulent lava flow d. decomposed organic matter e. magma that heats above its boiling point
A
What does it mean if an igneous rock has an aphanitic texture? a. the igneous rock exhibits mineral crystals too small to see with the naked eye b. an igneous texture that results from the cooling of magma below the surface of the Earth c. the igneous rock displays mineral crystals easily seen with the naked eye d. the igneous rock exhibits a texture that results from the slow cooling of molten rock e. this igneous rock texture can be described by a variety of both large and small mineral crystals
A
What is a magma chamber called after the conduit has solidified and been exposed by erosion? a. batholith b. dike c. sill d. volcanic neck e. volcanic conduit
A
What is a volcanic conduit called after the conduit has solidified and been exposed to erosion? a. volcanic neck b. hot spot c. volcano d. volcanic conduit
A
What is peridotite? a. the rock making up the mantle b. the mineral that absorbs water in the mantle c. the rock making up the subducting plate d. the mineral that releases water in the mantle
A
What lies underneath volcanic features at Earth's surface? a. magma chambers and volcanic conduits b. volcanic conduits and mantle chambers c. magma conduits and volcanic chambers d. mantle conduits and volcanic chambers
A
What type of plate interaction produces the San Andreas fault? a. plates sliding past one another b. diverging plates c. converging plates
A
Where are tectonic plates located? a. at Earth's surface b. below Earth's surface, near the core c. just under Earth's surface d. below Earth's surface, in the upper mantle
A
Which of the following would best describe the shape and composition of a volcano in the Cascade Range? a. cone-shaped volcano with alternating layers of lava and pyroclastic material b. broad, gently sloping volcano composed of layers of lava c. cone-shaped volcano composed of layers of lava d. cone shaped volcano composed of pyroclastic material e. broad, gently sloping volcano composed of alternating layers of lava and pyroclastic material
A
Why are shield volcanoes wider than composite volcanoes? a. the lava that flows out of shield volcanoes is more fluid than the lava that flows out of composite volcanoes b. the pyroclastic material that comes out of shield volcanoes is more fluid than the lava that flows out of composite volcanoes c. the lava that flows out of shield volcanoes is less fluid than the lava that flows out of composite volcanoes d. the pyroclastic material that comes out of shield volcanoes is less fluid than the lava that flows out of composite volcanoes
A
Why is Tuttle and Bowen's experiment useful to geologists? a. this experiment allows geologists to interpret where granitic rock solidifies beneath Earth's surface b. this experiment allows geologists to interpret where basaltic rock solidifies beneath Earth's surface c. this experiment allows geologists to interpret where granitic rock will emerge at Earth's surface d. this experiment allows geologists to interpret where basaltic rock will emerge at Earth's surface
A
Why is decompression melting common at mid-ocean ridges but not at subduction zones? a. tectonic plates are moving apart at mid-ocean ridges, resulting in a lowering of pressure beneath the ridge; tectonic plates are moving together at subduction zones, resulting in an increase of pressure under new mountains b. tectonic plates are moving together at mid-ocean ridges, resulting in an increase of pressure beneath the ridge; tectonic plates are moving apart at subduction zones, resulting in a lowering of pressure under new mountains c. tectonic plates are moving together at mid-ocean ridges, resulting in a lowering of pressure beneath the ridge; tectonic plates are moving apart at subduction zones, resulting in an increase of pressure under new mountains d. tectonic plates are moving apart at mid-ocean ridges, resulting in an increase of pressure beneath the ridge; tectonic plates are moving together at subduction zones, resulting in a lowering of pressure under new mountains
A
Yellowstone is best described as which of the following? a. an active volcano that has erupted in the last 1 million years b. an extinct volcano (it will never erupt again) c. a currently erupting volcano d. an active volcano that has erupted in the last 100 years
A
Which of the following could cause rock to melt? a. increase in temperature b. decrease in pressure c. decrease in temperature d. increase in pressure e. change in composition
A, B, E
Which of the following pieces of evidence for a past volcanic eruption are present at Yellowstone National Park? a. pyroclastic material b. lava flows c. a cone shaped volcano d. human documentation e. a caldera rim
A, B, E
When would a granitic magma remain a magma beneath Earth's surface? a. when the magma remains below the depth at which magmas become solid b. when the magma remains above the depth at which magmas become solid c. when the magma retains enough water to keep it from solidifying, regardless of depth d. when the magma loses enough water to keep it from solidifying, regardless of depth
A, C
Which of the following are type of volcanoes? a. shield volcano b. caldera c. composite volcano d. cinder cone e. cinder volcano
A, C, D
If previous eruptions had left Mount St. Helens with a different shape, what differences might have influenced the timing of the eruption? a. if the northern slopes had been less steep initially (same height), the eruption would likely have happened later b. if the northern slopes had been steeper initially (same height), the eruption would likely have happened later c. if the volcano had been significantly taller initially (same steepness), the eruption would likely have happened sooner d. if the volcano had been significantly shorter initially (same steepness), the eruption would likely have happened sooner
A, D
Which of the following features at Yellowstone National Park is evidence for a magma chamber beneath the park? a. rising (or bowing upward) ground near Yellowstone River b. a thin, recent layer of volcanic ash c. actively flowing lava d. welded tuff e. geysers and hot springs (steam)
A, D, E
Which of the following statements best describes a part of the process of the formation of the Cascade Mountain Range? a. rising of magma to the surface b. subduction of continental crust underneath oceanic crust c. decompression melting and crust thinning d. eruption of material at the surface e. partial melting due to the presence of water
A, D, E
A scientist creates diamonds using high-pressure laboratory experiments. These diamonds are not considered minerals because which of the following requirements has been violated? a. minerals must be inorganic in origin b. minerals must occur naturally c. minerals must have a known chemical composition d. minerals must be solid e. minerals must have an orderly crystalline structure
B
Hornblende has (blank) cleavage planes at (blank) angles. a. three; non-90 degree b. two; non-90 degree c. two; 90 degrees d. three; 90 degrees e. four; non-90 degree
B
How is the thickness of the lithosphere going to change as it moves away from a divergent plate boundary? a. thickness of the lithosphere will increase with the addition of continental material below b. lithosphere will thicken as more mantle is added c. lithosphere will thin as mantle material is sheared off d. the thickness will alternate between thick and thin due to collisional forces e. the thickness of the lithosphere will remain constant
B
How much material was removed from the volcano? a. 0.28 cubic kilometers of rock b. 2.8 cubic kilometers of rock c. 28 cubic kilometers of rock d. 280 cubic kilometers of rock
B
In addition to rock deposits, what evidence do we have that the eruption that preceded the formation of Crater Lake was very large? a. the eruption was so large that the volcano became unstable and collapsed, causing Crater Late to partially empty b. the eruption was so large that the magma chamber under Crater Lake partially emptied, causing the volcano to become unstable and collapse c. the eruption was so large that Crater Lake partially emptied, causing the volcano to become unstable and collapse d. the eruption was so large that the volcano became unstable and collapsed, causing the magma chamber under Crater Lake to partially empty
B
The offset of Wallace Creek is caused by (blank)? a. movement of the North American plate as it slides past the California plate in a northwest direction b. right-lateral movement along the San Andreas strike-slip fault c. left lateral slip along the San Andreas normal fault d. squeezing along the Big Bend over the past 2-4 million years e. subduction of the Pacific plate under the North American Plate
B
There had been many earthquakes in the area prior to this eruption; why did the last earthquake trigger a massive landslide? a. clearing of trees allowed erosion on the mountain slopes b. moving magma had over-steepened the mountain slopes c. extensive rain had weakened the mountain slopes
B
Transform boundaries are classified under which type of fault? a. reverse b. strike-slip c. normal
B
What are two differences between oceanic crust and continental crust? a. continental crust is thicker and denser than oceanic crust b. the continental crust is thicker and less dense than oceanic crust c. oceanic crust is thinner and is a liquid d. oceanic crust is denser and thicker than continental crust e. the oceanic crust is denser and therefore is below the continental crust
B
What causes an earthquake such as the one that occurred in San Francisco in 1906? a. when the two edges of a fault slowly glide past one another, an earthquake occurs b. as plates move, stress builds up at the boundary; when the boundary eventually snaps, energy is released as an earthquake c. an abrupt change in the direction of plate motion causes an earthquake to occur (e.g. when a plate that is moving northward suddenly moves to the south) d. as volumes of magma beneath the lithosphere rise toward the surface, the sudden upward thrust causes an earthquake to occur
B
What evidence supports that the glaciers on the southern continents were once part of a single, massive ice sheet? a. depositional ridges of sediment point out a direction of ice flow away from a central location b. striations c. glaciers reshaped continental coastlines to match d. decreasing thickness of glacial deposits from the center outward
B
What experiments did Tuttle and Bowen perform? a. tests of the temperature and pressure conditions required to melt basalt and form magma b. tests of the temperature and pressure conditions required to melt granite and form magma c. tests of the temperature and pressure conditions required to generate granite from basalt d. tests of the temperature and pressure conditions required to generate basalt from granite
B
What is fractional crystallization? a. melting of part of a rock, leaving behind solid rock with a different composition from the original magma b. crystallization of part of a magma, leaving behind melted rock with a different composition from the original magma c. crystallization of part of a magma, leaving behind melted rock with the same composition as the original magma d. melting of part of a rock, leaving behind solid rock with the same composition as the original magma
B
What is the difference between aa lava and pahoehoe lava? a. aa lava erupts from stratovolcanoes; pahoehoe erupts from shield volcanoes b. aa lava has a prickly texture; pahoehoe has a smooth, ropy texture c. pahoehoe lava is older than aa lava; that is why it displays more evidence of weathering d. aa lava is associated with basaltic eruptions; pahoehoe lava is associated with andesitic eruptions e. aa lava is made up of cinders; pahoehoe is formed from volcanic bombs
B
What is the range of dome complex height? a. 20 to 5,000 meters b. 500 to 2,000 meters c. 200 to 500 meters d. 20 to 500 meters
B
What is the range of shield volcano height? a. 300 to 1,000 meters b. 300 to 10,000 meters c. 3,000 to 10,000 meters d. 1,000 to 3,000 meters
B
What role do transform boundaries play? a. tranform boundaries create other segments of place boundaries b. transform boundaries connect other segments of plate boundaries c. transform boundaries replace other segments of plate boundaries d. transform boundaries destroy other segments of plate boundaries
B
What type of magma erupts out of dome complexes? a. mafelsic b. felsic magma c. felmafic magma d. mafic magma
B
What type of magma would you expect to see after crystallization of minerals containing significant amounts of iron? a. a magma enriched in iron b. a magma depleted in iron c. a magma with the same amount of iron as before
B
When was the last time the Earth had a magnetic reversal? a. 3.35 million years ago b. 700,000 years ago c. 900,000 years ago d. 4 million years ago e. 2.5 million years ago
B
Where does the water involved in melting at subduction zones come from? a. water contained within minerals in the overriding plate is released during metamorphism b. water contained within minerals in the subducting plate is released during metamorphism c. water from the ocean is pulled down by the subducting plate and released during metamorphism d. water from the ocean is pulled down by the subducting plate, is absorbed into minerals, and is released during metamorphism
B
Which of the following best describes the term streak? a. when both light and an image are visible through a mineral sample b. the color of a powdered form of a mineral produced by rubbing it across a hard surface c. the amount or quality of light reflected from a mineral surface d. when no light is transmitted through a mineral sample e. the arrangement of atoms in an orderly, repetitive structure
B
Which of the following statements about earthquakes with magnitude greater than 4.0 is most accurate? a. earthquakes with magnitude greater than 4.0 occur in a pattern than correlates closely with hot spots b. earthquakes with magnitude greater than 4.0 occur in a pattern than correlates closely with plate boundaries c. earthquakes with magnitude greater than 4.0 occur in a pattern than correlates loosely with hot spots d. earthquakes with magnitude greater than 4.0 occur in a pattern than correlates loosely with plate boundaries
B
Which of the following statements about rock melting is most accurate? a. rock can only remain solid, become partially melted, or melt completely at each depth within Earth, regardless of temperature b. rock can remain solid, become partially melted, or melt completely at the same depth within Earth, depending on the temperature c. rock an remain solid or become partially melted at the same depth within Earth, depending on the temperature
B
Which phenomenon can explain the presence of volcanoes in the middle of the Pacific Ocean? a. earthquakes b. hot spots c. transform motion d. subduction e. divergence
B
Which type of plate boundary is most closely associated with uplifting continental regions and mountain building? a. divergent boundaries b. convergent boundaries c. hot spot boundaries d. transform boundaries
B
Why does magma composition change during fractional crystallization? a. different magmas in the crystals form at different rates, leaving behind less of the unused elements b. different elements in the magma form crystals at different rates, leaving behind more of the unused elements c. different magmas in the crystals form at different rates, leaving behind more of the unused elements d. different elements in the magma form crystals at different rates, leaving behind less of the unused elements
B
You have found a mafic rock with a phaneritic texture. What is a potential rock name? a. andesite b. gabbro c. diorite d. olivine e. granite
B
How do calderas form? a. calderas form when a collapsed volcano summit fills with water b. calderas form when the summit of a volcano forms c. calderas form when the summit of a volcano collapses d. calderas form when a volcano lies dormant
C
How does water content of granitic magmas change as the magmas move towards Earth's surface? a. water content remains the same b. water content increases c. water content decreases
C
In general, how often do most cinder cones erupt? a. most cinder cones erupt seasonally b. most cinder cones do not erupt c. most cinder cones erupt once d. most cinder cones erupt annually e. most cinder cones erupt several times each decade
C
In general, when will melted rock in the mantle rise? a. almost never b. sometimes, depending on the magma's temperature c. almost always d. sometimes, depending on the magma's pressure
C
In general, why does Earth's crust sit on top of the mantle? a. Earth's crust is denser than the mantle b. Earth's crust is hotter than the mantle c. Earth's crust is less dense than the mantle d. Earth's crust is colder than the mantle
C
Minerals must be solid, have an orderly atomic structure, have a recognized chemical composition, be naturally occurring, and (blank). a. made by organisms b. found only in igneous rocks c. be generally inorganic in origin d. be reproducible in a laboratory setting e. be a highly valued natural resource
C
The principal mineral used in making glass is? a. gold b. hematite c. quartz d. copper e. talc
C
What are the three types of plate boundaries? a. divergent, convergent, and transverse b. digressive, convergent, and transform c. divergent, convergent, and transform d. divergent, converse, and transform e. divergent, converse, and transform
C
What is an accurate description of the silicon-oxygen tetrahedron? a. the silicon-oxygen tetrahedron is a pyramid-shaped feature that commonly bonds to negative ions to produce silicate minerals b. the silicon-oxygen tetrahedron is a double-chained structure of the amphibole group c. the silicon-oxygen tetrahedron is a four-sided figure with a silicon atom in the middle bonded to four neighboring oxygen atoms d. the silicon-oxygen tetrahedron is a structure that is a significant building block to nonsilicate minerals e. the silicon-oxygen tetrahedron is a four-sided figure with an oxygen atom in the middle bonded to four neighboring silicon atoms
C
What is piled up along the cone of SP Crater that causes it to be so steep? a. loose black pebbles b. volcanic ash c. cinders d. volcanic bombs e. a lava flow
C
What material was added to powdered rock during Tuttle and Bowen's experiments? a. magma b. pressure c. water d. air
C
What minerals make up rhyolite? a. muscovite, biotite, and clays b. olivine and pyroxenes c. quartz, K-feldspar, and plagioclase feldspars, with relatively fewer biotite and amphiboles d. amphiboles and pyroxenes e. ca-plagioclase, biotite, and amphiboles
C
What type of volcano is Mount St. Helens? a. plinian b. shield c. composite d. cinder cone
C
Where is Crater Lake? a. Arizona b. Florida c. Oregon d. Virginia e. Texas
C
Which of the following best describes the term cleavage? a. cleavage is the characteristic growth pattern or shape of a mineral b. cleavage is the colored mark that a mineral makes when scratched on a porcelain tile c. cleavage is the splitting of minerals along natural planes of weakness d. cleavage describes the quality and amount of light reflected from a mineral surface e. cleavage describes a mineral's resistance to abrasion
C
Which of the following exhibits three sets of cleavage at 90 degree angles? a. feldspar b. fluorite c. galena d. calcite e. mica
C
Which of the following is a mineral? a. plastic b. charcoal c. ice d. water e. granite
C
Which of the following is true about mafic igneous rocks? a. mafic igneous rocks are rich in Si, K, and Na b. mafic igneous rocks have a melting temperature around 650 degrees C c. mafic igneous rocks are rich in Fe, Mg, and Ca d. mafic igneous rocks are dominantly composed of muscovite and quartz e. mafic igneous rock exmaples include diorite and andesite
C
Which of these most directly triggered the main eruption? a. mud flows in the Toutle river b. avalanches of pyroclastic debris c. a massive landslide d. the formation of a bulge on the north slope e. outgassing of the magma
C
Which part of the earth is responsible for generating the planet's magnetic field? a. continental lithosphere b. oceanic lithosphere c. core d. mantle e. crust
C
Which plate boundary is NOT associated with volcanic eruptions? a. divergent b. convergent c. transform d. converse
C
Which two processes commonly generate magma? a. compression melting and wet melting (the addition of volatiles) b. compression melting and dry melting c. decompression melting and wet melting (the addition of volatiles) d. decompression melting and dry melting
C
Why does Crater Lake have an island in it? a. the volcano is still active, and a new caldera has formed b. the volcano is inactive, and a new volcanic peak has formed c. the volcano is still active, and a new volcanic peak has formed d. the volcano is inactive, and a new caldera has formed
C
the belief that Earth's landscapes were shaped primarily by great catasthrophic events of a short-term nature
Catastrophism
the part of the continental crust that has attained stability; that is, it has not been affected by significant tectonic activity during the Phanerozoic eon; it consists of the shield and the stable platform
Craton
Cinder cones are made of (blank)? a. pyrobasalt deposits b. basalt flows c. granite flows d. pyroclastic deposits
D
Do fracture zones near transform boundaries play a role in plate motion? a. yes, fracture zones mark areas where plate are moving past each other b. yes, fracture zones mark areas where plates are moving away from each other c. yes, fracture zones mark areas where plates are moving toward each other d. no, fracture zones play no role in plate motion
D
How do mafic volcanic rocks get to Earth's surface? a. heat from the lower crust melts part of the mantle to form magma that rises to Earth's surface; these magmas erupt out of volcanoes, cool, and solidify into rock. b. heat from the mantle melts part of the lower crust to form magma, which rises to Earth's surface; these magmas erupt out of volcanoes, cool, and solidify into rock c. pressure from overlying mantle forces crust magmas through cracks to Earth's surface; these magmas erupt out of volcanoes, cool, and solidify into rock d. pressure from overlying crust forces mantle magmas through cracks to Earth's surface; these magmas erupt out of volcanoes, cool, and solidify into rock
D
How is information about magnetic fields recorded in rocks? a. rust particles in sedimentary rocks align with the Earth's magnetic field b. marine organisms align with the Earth's magnetic field and are preserved in sedimentary rocks c. iron particles in basalt rocks become aligned with the magnetic field of the Earth d. iron particles in magnetically susceptible mineral within basaltic lava align with the magnetic field of the Earth while the lava is still liquid and then freeze in position when the lava solidifies e. the mid-ocean ridge spreading direction will align with the Earth's magnetic field
D
How was the fossil record of ancient life used to support Wegener's hypothesis about Pangea? a. fossils are evidence of mass migrations of organisms in search of resources on other continents b. organisms on multiple continents are independently evolved to have the same appearance c. organisms used a series of islands to "leap frog" to another, stationary continent d. fossils of identical organisms were found on several continents, indicating the continents were once joined e. the identical fossils are all marine fossils, indicating that the continents were all once covered by a global sea
D
How were scientists able to determine the date of the magnetic reversals during seafloor spreading? a. deep-sea clays b. magnetic signatures c. seawater isotopes d. continental landmasses e. small marine fossils in deep-sea sediments give the age of the portions of the seafloor
D
Igenous rocks of felsic composition have (blank) and (blank) relative to mafic igenous rocks. a. greater Ca; lower melting temperature b. darker color, lower melting temperature c. greater K and Na; higher melting temperature d. greater silica; lower melting temperature e. lighter color; higher melting temperature
D
Intrusive and extrusive igneous rocks are classified based on what criteria? a. the composition of the molten rock and how quickly it cools and crystallizes b. the composition of the molten rock, and where it cools with respect to Earth's surface c. the linked framework of the silicon-oxygen tetrahedra, and where the molten rock cools with respect to Earth's surface d. how quickly the molten rock cools and crystallizes, and where this occurs with respect to Earth's surface e. the grain size and composition of the igneous rock
D
Late Paleozoic sedimentary rocks often contain extensive coal seams that were used to support the existence of Pangea. What would the climate have been at that time and at the location where the coal deposits were formed, and what would it indicate about the continent's past latitude? a. temperate climate in the mid-latitudes b. cold climate near the South Pole c. arid climate near the Equator d. warm, humid climate near the Equate e. polar tundra climate
D
Regardless of their size most rocks are made up of (blank)? a. magma b. synthetic minerals c. grains d. minerals
D
Since color is not a very useful way to identify a mineral, what other optical property or properties can be used? a. internal structure and transparency b. opacity c. chemical composition d. luster and streak e. strength
D
The bend in the stone walls in the town of Hollister, California are a result of (blank)? a. groundwater withdrawal from a former sag pond b. a large earthquake that caused major loss of life and property damage c. ground subsidence due to compaction of unlithified sediments d. a fault creep along the Calaveras Fault e. extensive igneous activity whereby magma rose towards the surface, causing structural damage
D
What are shield volcanoes generally made of? a. granite flows b. pyrobasalt deposits c. pyroclastic deposits d. basalt flows
D
What are the two most abundant elements in Earth's crust? a. iron and aluminum b. silicon and aluminum c. silicon and calcium d. oxygen and silicon e. oxygen and iron
D
What geologic process is related to caldera formation? a. hurricanes b. tsunami c. landslides d. volcanism e. river erosion
D
What is the difference between a dike and a sill? a. a sill leads to volcanoes above sedimentary layers, and a dike leads to volcanoes below sedimentary layers b. a dike leads to volcanoes above sedimentary layers, and a sill leads to volcanoes below sedimentary layers c. a still intrudes across sedimentary layers, and a dike intrudes between sedimentary layers d. a dike intrudes across sedimentary layers, and a sill intrudes between sedimentary layers
D
What is the main material being subducted at an ocean-continent convergent boundary? a. oceanic crust only b. asthenosphere c. continental crust only d. oceanic lithosphere e. continental lithosphere
D
What is the relationship between transform boundaries and mid-ocean ridges? a. transform boundaries create segments of mid-ocean ridges b. transform boundaries move segments of mid-ocean ridges c. transform boundaries destroy segments of mid-ocean ridges d. transform boundaries connect segments of mid-ocean ridges
D
What minerals make up half of the Earth's crust? a. quartz and amphiboles b. quartz and pyroxenes c. amphiboles, micas, and clays d. feldspars e. nonsilicates
D
What type of volcanoes are the highest? a. dome complexes b. cinder cones c. composite volcanoes d. shield volcanoes
D
When matching up once-joined continents such as South America and Africa, the coastlines do not fit together as nicely as the continental shelves. Why might this be the case? a. large volumes of sediment eroded from the continent fills in the gaps between the shelves b. the coastlines have been altered by the vast deposits of lava c. separation of the continents resulted in deformation of the coastlines d. the continental shelves are the edges of the continent; the shoreline simply shows where the sea level is in relation to topography
D
When will magma rise to Earth's surface? a. when the magma has more volume than adjacent rock b. when the magma has more mass than adjacent rock c. when the magma is denser than adjacent rock d. when the magma is less dense than adjacent rock
D
Which of the following statements best describes Wegener's idea of continental drift? a. continents are subsiding into the sea b. ancient organisms had undergone mass migrations to reach the continents where they are found today c. global oceans were draining, which exposed stationary parts of the seafloor we now call continents d. continents were formerly in different positions on the Earth and have shifted to their present locations over time e. continents are building up through sedimentation
D
Which of the following statements best represents the relationship between magma and crystals formed from the magma? a. the crystals contain more volume than the magma b. the crystals are less dense than the magma c. the crystals contain more mass than the magma d. the crystals are denser than the magma
D
Which of the following volcanoes is associated with the Ring of Fire? a. killimajaro b. hekla volcano c. manua loa d. Mt. Pinatubo e. Mt. Vesuvius
D
Which of the following was a stage in the formation of Yellowstone caldera? a. the magma chamber emptied completely during the eruption b. pyroclastic material erupted from a single vent c. material exploded from the center of the caldera d. crust blows upward above a magma chamber
D
Why are volcanic rocks often exposed at Earth's surface as hills, ridges, and mountains surrounded by areas of lower elevation? a. volcanic rocks are often more susceptible to erosion than surrounding rock b. volcanic rocks are often younger than surrounding rock c. volcanic rocks are often older than surrounding rock d. volcanic rocks are often more resistant to erosion than surrounding rock
D
Why glass is not considered a mineral? a. glass is made by organisms b. glass has an unknown chemical composition c. glass is solid d. glass has a disorderly atomic structure e. glass is not naturally occurring
D
which of the following substances is a mineral? a. amber b. petroleum c. granite d. quartz e. pearl
D
felsic
Describes magma or igneous rock that is rich in feldspars and silica and that is generally light in color.
(blank) SiO4^4- tetrahedra join with (blank) ions to produce the mineral olivine in the rock peridotite. a. double chain; positive b. independent; negative c. single chain; Mg^2+ and Fe^2+ d. three dimensional; Ca^2+ and Na^1+ e. independent; Mg^2+ and Fe^2+
E
A phaneritic texture is characteristic of a(n) (blank) igneous rock that cooled (blank). a. extrusive; below the surface b. extrusive; at Earth's surface c. extrusive; over a long period of time d. intrusive; very quickly e. intrusive; below the surface
E
Earth's outer layer is composed of seven dominant plates. What is the name of this rigid outer layer? a. mesosphere b. mantle c. asthenosphere d. hydrosphere e. lithosphere
E
How are igneous rocks formed? a. igneous rocks are formed only from material ejected during a volcanic eruption b. igneous rocks are produced by the weathering and transport of pre-existing rocks c. igneous rocks are formed by the cooling of magma above Earth's surface and lava below the surface d. igneous rocks are formed by recrystallization due to intense heat and pressure e. igneous rocks are formed by the cooling and crystallization of molten rock
E
Oceanic lithosphere contains oceanic crust and the (blank). a. innermost part of the mantle b. continental crust c. outer core d. asthenosphere e. outermost part of the mantle beneath the oceanic crust
E
What causes a lack of cleavage in some minerals? a. the shape of the mineral b. bonds of differing strength in certain directions c. the chemical composition of the mineral d. a small impurity in the atomic structure e. bonds of equal strength in all directions
E
What causes the same mineral to occur in varieties that are different colors? a. the ability to transmit light varies in the same mineral b. the amount and quality of light reflected off the surface differs in the same mineral c. chemical bonds are rearranged in the same mineral d. the crystalline structure often exhibits differences in shape e. a small amount of impurities in the crystal structure
E
What information do geologists use to classify volcanoes? a. height of peak and type of deposits b. shape and height of peak c. color and type of deposits d. color and height of peak e. shape and type of deposits
E
What is one way that cinder cones differ from composite and shield volcanoes? a. only cinder cone volcanoes are topped by craters b. cinder cones can only be found in Arizona, whereas composite and shield volcanoes are found all over the world c. cinder cones are the only type of volcano with basaltic lava d. cinder cones form slowly, whereas shields and stratovolcanoes can form in less than one year e. cinder cones are smaller than composite and shield volcanoes
E
What is required to generate and igneous rock with a fine-grained texture? a. a fine-grained texture is the product of very slow cooling and crystallization of magma b. a fine-grained texture results from large grains that recrystallize to smaller grains with increased heat and pressure c. a fine-grained texture requires an environment where heat is lost slowly over a long period of time d. a fine-grained texture results from cooling far below the crust e. a fine-grained texture is the product of rapid cooling and crystallization of lava
E
Which of the following is a layer of the Earth that is classified NOT by composition, but by physical properties? a. geosphere b. crust c. mantle d. core e. asthenosphere
E
Which one of the following statements is NOT true about andesite and basalt? a. cinder cones can be comprised of either andesite or basaltic magma b. basalt has more iron and magnesium than andesite c. andesite and basalt are extrusive igneous rocks d. andesite has more silica than basalt e. basaltic lava is thicker than andesitic lava
E
Why is water a necessary component of the melting process in subduction zones? a. water creates a buoyant force that allows the magma to rise b. the addition of water lowers the friction experienced by rising magma c. water changes the density of the rock, allowing the rock to melt d. water is a liquid, and rock needs to encounter a liquid in order to become a liquid e. the addition of water lowers the melting temperature of rock
E
Anglican Archbishop of Armagh, Primate of all Ireland, who constructed a chronology of human and Earth history in which he calculated that Earth was only a few thousand years old, having been created in 4004 B.C.
James Ussher
the zone of active volcanoes surrounding the Pacific Ocean
Ring of Fire
igneous rock
a type of rock that forms from the cooling of molten rock at or below the surface
a type of lava flow that has a jagged, blocky surface
aa flow
a texture of igneous rocks in which the crystal are too small for individual minerals to be distinguished without the aid of a microscope
aphanitic texture
the smallest particle that exists as an element
atom
a large mass of igneous rock that formed when magma was emplaced at depth, crystallized, and subsequently exposed by erosion
batholith
a large depression typically caused by collapse or ejection of the summit area of a volcano
caldera
a strong attractive force that exists between atoms in a substance; it involves the transfer or sharing of electrons that allows each atom to attain a full valence shell
chemical bond
a rather small volcano built primarily of ejected lava fragments that consist mostly of pea- to walnut-size lapilli
cinder cone
the tendency of a mineral to break along planes of weak bonding
cleavage
a phenomenon of light by which otherwise identical objects may be differentiated
color
a volcano composed of both lava flows and pyroclastic material
composite cone
the portion of the seafloor that is adjacent to the continents; it may include the continental shelf, continental slope, and continental rise
continental margin
a boundary in which two plates move together, resulting in oceanic lithosphere being thrust beneath an overriding plate, eventually to be reabsorbed into the mantle; it can also involve the collision of two continental plates to create a mountain system
convergent plate boundary
a silicate mineral that contains ions of iron and/or magnesium in its structure; dark silicates are dark in color and have a higher specific gravity than nonferromagnesian silicates
dark silicate or ferromagnesian
a property of matter defined as mass per unit volume
density
mafic
describes magma or igneous rock that is rich in magnesium and iron and that is generally dark in color
a tabular-shaped intrusive igneous feature that cuts through the surrounding rock
dike
a boundary in which two plates move apart, resulting in upwelling of material from the mantle to create new seafloor
divergent plate boundary
a negatively charged subatomic particle that has a negligible mass and is found outside an atom's nucleus
electron
a substance that cannot be decomposed into simpler substances by ordinary chemical or physical means
element
flows of basaltic lava that issue from numerous cracks or fissures and commonly cover extensive areas to thicknesses of hundreds of meters
flood basalts
any break or rupture in rock along which no appreciable movement has taken place
fracture
the span of time since the formation of Earth, about 4.6 billion years
geologic time
the division of Earth history into blocks of time- eons, eras, periods, and epochs; the time scare was crated using relative dating principles
geologic time scale
a term used to describe the texture of certain igneous rocks, such as obsidian, that contain no crystals
glassy
a mineral's resistance to scratching and abrasion
hardness
a concentration of heat in the mantle, capable of producing magma that, in turn, extrudes onto Earth's surface; the intraplate volcanism that produced the Hawaiian Islands is one example
hot spot
a tunnel in hardened lava that acts as a horizontal conduit for lava flowing from a volcanic vent; lava tubes allow fluid lavas to advance great distances
lava tube
a silicate mineral that lacks iron and/or magnesium; light silicates are generally lighter in color and have lower specific gravities than dark silicates
light silicate or nonferromagnesian
the appearance or quality of light reflected from the surface of a mineral
luster
a continuous mountainous ridge on the floor of all the major ocean basins and varying in width from to 500 to 5000 kilometers (300 to 3000 miles); the rifts at the crests of these ridges represent divergent plate boundaries
mid-ocean ridge
a naturally occurring, inorganic crystalline material with a unique chemical structure
mineral
a model for the origin of the solar system that supposes a rotating nebula of dust and gases that contracted to form the Sun and planets
nebular theory
a subatomic particle found in the nucleus of an atom; the (blank) is electrically neutral, with a mass approximately equal to that of a proton
neutron
a lava flow with a smooth to ropy surface
pahoehoe flow
a texture of igneous rocks in which the interlocking crystals are all larger than one centimeter in diameter
pegmatitic texture
an igneous rock texture in which the crystals are roughly equal in size and large enough so that individual minerals can be identified without the aid of a miroscope
phaneritic texture
a structure that results from the emplacement and crystallization of magma beneath the surface of the Earth
pluton
an igneous rock texture characterized by two distinctively different crystal sizes; the larger crystals are called phenocrysts, whereas the matrix of smaller crystals is termed the groundmass
porphyritic texture
a positively charged subatomic particle that found in the nucleus of an atom
proton
the volcanic rock ejected during an eruption; pyroclastics include ash, bombs, and blocks
pyroclastic material
a large, relatively flat expanse of ancient igneous and metamorphic rocks within the craton
shield
any one of numerous minerals that have the silicon-oxygen tetrahedron as their basic structure
silicate mineral
a tabular igneous body that was intruded parallel to the layering of preexisting rock
sill
the color of a mineral in powdered form
streak
a theory which proposes that Earth's outer shell consists of individual plates that interact in various ways and thereby produce earthquakes, volcanoes, mountains, and the crust itself
theory of plate tectonics
a boundary in which two plates slide past one another without creating or destroying lithosphere
transform fault boundary
the concept that the processes that have shaped Earth in the geologic past are essentially the same as these operating today
uniformitarianism
a term applied to aphanitic igneous rocks that contain many small cavities called vesicles
vesicular
a measure of a fluid's resistance to flow
viscosity
gaseous components of magma dissolved in the melt; will readily vaporize (form a gas) at surface pressures
volatiles
