Mastering Geography Assn. #7 - PHSC 131

64) Rough, sharp-edged lava is known as: A) Scoria. B) Peridotite. C) aa. D) Obsidian. E) Pahoehoe.

C) aa.

56) The subsurface area where the motion of seismic waves is initiated along the fault plane is called the: A) Epicenter. B) Moho. C) Focus, or hypocenter. D) Mercalli point. E) Richter zone.

C) Focus, or hypocenter.

61) Mounting evidence indicates that the dramatic increase in the number of earthquakes in the central United States is caused by: A) The re-awakening of a long dormant fault. B) Geothermal energy production. C) Large wind turbine farms. D) Deep wastewater injection wells. E) Global climate change.

D) Deep wastewater injection wells.

57) The area at the surface directly above the subsurface location where seismic waves are initiated is termed the: A) Mercalli point. B) Fault area. C) Focus, or hypocenter. D) Epicenter. E) Richter zone.

D) Epicenter.

51) A(n)________is displacement of the ground surface caused by faulting. A) Dome. B) Hanging wall. C) Anticline. D) Escarpment. E) Fracture zone.

D) Escarpment.

18) Which rock type makes up approximately 90% of the Earth's crust? A) Clastic. B) Foliated. C) Metamorphic. D) Igneous. E) Sedimentary.

D) Igneous.

46) Folded layers of rock can form a wavelike pattern of troughs and crests. The layers near the crest (i.e., the upward fold) form: A) A tension zone. B) A syncline. C) Shear. D) A thrust fault. E) An anticline.

E) An anticline.

43) The nucleus of old crystalline rock in each of the principal continental masses is called a: A) Terrane. B) Composite zone. C) Mountain mass. D) Basalt mass. E) Craton.

E) Craton.

28) The_________drives the exogenic processes of the rock cycle. A) Tectonic cycle. B) Biogeochemical cycle. C) Rock cycle. D) Atmospheric circulation. E) Hydrologic cycle.

E) Hydrologic cycle.

67) A gently sloping mountain landform built from effusive eruption is known as a: A) Shield volcano. B) Crater. C) Pluton. D) Caldera. E) Cinder cone.

A) Shield volcano.

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART H The East African rift is a divergent plate boundary that is splitting the continent of Africa into two pieces. What will eventually form around this divergent boundary? A) A convergent boundary. B) An ocean. C) A hurricane. D) A continent. E) A transform boundary.

B) An ocean.

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART D In general, where do BOTH earthquakes AND volcanic eruptions occur? Choose all that apply. A) Away from plate boundaries. B) At convergent plate boundaries. C) At transform plate boundaries. D) At divergent plate boundaries.

B) At convergent plate boundaries. & D) At divergent plate boundaries.

66) Small, circular surface depressions usually found at or near the summit of a volcano are as: A) Cinder cones. B) Craters. C) Calderas. D) Domes. E) Shield volcanoes.

B) Craters.

19) Coarser grained igneous rocks tend to be________because________. A) Either intrusive or extrusive; the slower cooling of magma & lava allows more time for crystals to form. B) Intrusive; slower cooling of magma allows more time for crystals to form. C) Extrusive; the slower cooling of lava allows more time for crystals to form. D) Extrusive; the faster cooling of lava allows more time for crystals to form. E) Intrusive; the faster cooling of magma allows more time for crystals to form.

B) Intrusive; slower cooling of magma allows more time for crystals to form.

54) At this convergent boundary, a subduction zone forms as the result of density differences of the converging plates. A) Continental plate--continental plate. B) Oceanic plate--continental plate. C) Continental shield--craton. D) Oceanic plate--oceanic plate. E) Terrane--craton.

B) Oceanic plate--continental plate.

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART A How do plates move at divergent plate boundaries? A) Plates move together. B) Plates move apart. C) Plates move side by side. D) Plates do not move.

B) Plates move apart.

7) The scientific study of rock strata (layers) is known as_________and based on the principle of________. A) Paleogeography; plate tectonics. B) Stratigraphy; superposition. C) Sedimentology; deposition. D) Geomorphology; uniformitarianism. E) Paleontology; catastrophism.

B) Stratigraphy; superposition.

5) The Precambrian Eon encompasses what percentage of Earth's total history? A) 0.04% B) 5% C) 88.3% D) 54.1% E) 72.4%

C) 88.3%

24) Limestone formed from the shells of marine organisms is an example of___________sedimentary rock. A) Clastic. B) Contact. C) Inorganic. D) Biochemical. E) Extrusive.

D) Biochemical.

52) The San Andreas system in California is an example of: A) A strike-slip fault, only. B) A transform fault, only. C) A thrust fault, only. D) Both a strike-slip & transform fault. E) A strike-slip fault, a transform fault, & a thrust fault.

D) Both a strike-slip & transform fault.

40) Transform faults along plate boundaries are typically associated with: A) Near seafloor creation. B) Volcanism. C) Subduction zones. D) Earthquake activity. E) Sea-floor spreading centers.

D) Earthquake activity.

53) Orogenesis refers to: A) Eroding away of surface material to expose a craton (continental shield). B) A general thinning of the crust. C) The creation of an escarpment during normal faulting. D) The beginning of extensive faulting. E) A general term for a mountain-building episode that thickens continental crust.

E) A general term for a mountain-building episode that thickens continental crust.

41) The Hawai'ian Islands were formed as a result of: A) Activity along a mid-ocean ridge. B) A continental-oceanic plate collision. C) An oceanic-oceanic plate collision. D) Divergent plate boundaries. E) A rising plume of magma from the mantle.

E) A rising plume of magma from the mantle.

31) Pangaea is currently dated at: A) 225 million years ago. B) 65 million years ago. C) About half the time-span of Earth's existence. D) 4.6 billion years ago. E) The beginning of the Holocene.

A) 225 million years ago.

47) Folded layers of rock can form a wavelike pattern of troughs and crests. The layers near the trough (i.e., downward fold) form: A) A syncline. B) A tension zone. C) An anticline. D) Shear. E) A thrust fault.

A) A syncline.

36) Earth's crust is roughly made up of: A) At least 14 plates capable of movement. B) Strong, unbroken material. C) A brittle material that does not move. D) Mantle and core material. E) 2 large plates and 22 microplates.

A) At least 14 plates capable of movement.

22) Sedimentary rock formed from the combined processes of weathering, erosion, transportation, deposition, lithification, and compaction of rock fragments of other rocks are: A) Clastic. B) Organic. C) Biochemical. D) Basaltic. E) Chemical.

A) Clastic.

3) Which is the correct order of geologic time spans, from largest to smallest? A) Eon - era - period - epoch. B) Eon - epoch - period - era. C) Epoch - era - period - eon. D) Epoch - period - era - eon. E) Era - eon - epoch - period.

A) Eon - era - period - epoch.

20) Finer grained igneous rocks tend to be_______because_______. A) Extrusive; the faster cooling of lava limits time for crystals to form. B) Either intrusive or extrusive; the faster cooling of magma & lava limits time for crystals to form. C) Extrusive; the slower cooling of lava limits time for crystals to form. D) Intrusive; the faster cooling of magma limits time for crystals to form. E) Intrusive; slower cooling of magma limits time for crystals to form.

A) Extrusive; the faster cooling of lava limits time for crystals to form.

50) When rock strata are strained beyond their ability to remain an intact unit, displacement occurs in a process known as: A) Faulting. B) Stressing. C) Shearing. D) Folding. E) Broad warping.

A) Faulting.

16) What type of rock forms from the solidification of molten material? A) Igneous. B) Sedimentary. C) Clastic. D) Metamorphic. E) Foliated.

A) Igneous.

48) The principles of buoyancy & balance, when applied to Earth's crust, helps us to explain fluctuations in Earth's outer crust, a property known as: A) Isostasy. B) Folding. C) Moho effect. D) Faulting. E) Orogenesis.

A) Isostasy.

17) Molten rock beneath the Earth's surface is known as_______, whereas molten rock on the Earth's surface is called_______. A) Magma; lava. B) Intrusive; extrusive. C) Lava; extrusive. D) Extrusive; intrusive. E) Lava; magma.

A) Magma; lava.

4) Boundaries between intervals of the geological time scale are determined by: A) Major events in the Earth's history, such as major extinctions. B) Dividing the time range of the interval by the number desired subdivisions, thereby creating equal intervals between the divisions. C) Historical misunderstandings based on the principle of uniformitarianism; they remain as relics of this bygone scientific period. D) Using a quantile method whereby the number of years in each subdivision is determined by dividing the number of years by the desired number of classes. E) Climatic periods based on paleoclimatological reconstructions.

A) Major events in the Earth's history, such as major extinctions.

59) The______scale would use Roman numerals to qualitatively describe an earthquake based on actual effects experienced at the exact time & location of the quake. A) Modified Mercalli Intensity. B) Mohs. C) Beaufort. D) Richter. E) Moment Magnitude.

A) Modified Mercalli Intensity.

55) At this convergent boundary, volcanic island arcs form where one plate is subducted under another. A) Oceanic plate--oceanic plate. B) Continental plate--continental plate. C) Terrane--craton. D) Oceanic plate--continental plate. E) Continental shield--craton.

A) Oceanic plate--oceanic plate.

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART F In general, where do volcanoes form in subduction zones? A) On the overriding plate, away from the convergent boundary. B) On the subducting plate, away from the convergent boundary. C) On the overriding plate, at the convergent boundary. D) On the subducting plate, at the convergent boundary.

A) On the overriding plate, away from the convergent boundary.

65) Lava that forms ropy cords in twisted folds is called: A) Pahoehoe. B) Obsidian. C) Scoria. D) aa. E) Peridotite.

A) Pahoehoe.

30) _________is the theory that describes the motion of the Earth's lithosphere. A) Plate tectonics. B) Sea floor spreading. C) Metamorphism. D) Pangaea. E) Orogeny.

A) Plate tectonics.

44) Most cratons date to the: A) Precambrian eon. B) Paleocene epoch. C) Mesozoic era. D) Devonian period. E) Paleozoic era.

A) Precambrian eon.

27) The continuous alteration of Earth materials from one rock type to another is known as the: A) Rock cycle. B) Biogeochemical cycle. C) Geologic cycle. D) Hydrologic cycle. E) Tectonic cycle.

A) Rock cycle.

15) The three basic rock types are: A) Sedimentary, metamorphic, and igneous. B) Intrusive, extrusive, and plutonic. C) Felsic, mafic, and ultramafic. D) Laterite, schist, and basalt. E) Conglomerates, clastics, and evaporative.

A) Sedimentary, metamorphic, and igneous.

21) What type of rock is derived from the bits & pieces of former rocks? A) Sedimentary. B) Hydrothermal. C) Mafic. D) Igneous. E) Metamorphic.

A) Sedimentary.

58) An instrument used to record vibrations in the crust is the: A) Seismograph. B) Tiltmeter. C) Sextant. D) Land barometer. E) The Richter scale.

A) Seismograph.

6) Uniformitarianism assumes that: A) The same physical processes we see today are a key to understanding the processes that have been operating throughout geologic time. B) Mountains, plains, and canyons formed by catastrophic events. C) Catastrophic episodes have regularly occurred. D) Earth is quite young & is shaped by dramatic events. E) Much of Earth history is ultimately unknowable & we must therefore only concentrate on those parts that have been documented by written historical events.

A) The same physical processes we see today are a key to understanding the processes that have been operating throughout geologic time.

60) Within the United States, which area has the highest earthquake hazards? A) West Coast. B) Upper Midwest. C) East Coast. D) Mid-continent. E) Gulf coast.

A) West Coast.

34) How does the ocean floor preserve evidence of past magnetic reversals? A) The ocean floor is uniformly old, preserving the Earth's 4.6 billion history. B) Magnetic particles in basalt orient with the magnetic field in force at the time the oceanic lava cooled and hardened. C) Isotopic analysis of ocean core sediments help determine sea floor age & this can be used to infer past magnetism. D) Mantle hot spots are always oriented to the magnetic field. E) The oldest oceanic crust is always found near mid-ocean ridges. As one moves out from these ridges, the crust is simultaneously younger & oriented according to the polarity at the time.

B) Magnetic particles in basalt orient with the magnetic field in force at the time the oceanic lava cooled and hardened.

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART E What forms at divergent plate boundaries? A) New continental lithosphere. B) New oceanic lithosphere.

B) New oceanic lithosphere.

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART G Why are volcanoes NOT found at transform boundaries? A) Transform boundaries cause decreases in temperature that exactly offset increases in pressure of the mantle. B) Transform boundaries do not cause changes to the pressure, temperature, or composition of the mantle. C) Transform boundaries cause increases in temperature that exactly offset decreases in pressure of the mantle. D) Transform boundaries cause changes to the pressure, temperature, or composition of the mantle.

B) Transform boundaries do not cause changes to the pressure, temperature, or composition of the mantle.

45) A large region where a craton is exposed at the surface is known as a: A) Continental platform. B) Terrane. C) Continental shield. D) Mountain mass. E) Composite zone.

C) Continental shield.

39) Areas of crustal collision & subduction occur along: A) Mid-ocean ridges. B) Areas of seafloor spreading. C) Convergent boundaries. D) Transform boundaries. E) Divergent boundaries.

C) Convergent boundaries.

49) Glaciers that once covered the Hudson Bay area melted 8,000 years ago. As a result of this, the bay is gradually rising. In another 10,000 years or so, it will have risen above sea level & become dry. This process can best be considered an example of: A) Shear. B) Accretion. C) Isostasy. D) Orogenesis. E) Catastrophism.

C) Isostasy.

62) Molten rock that pours forth on Earth's surface is called: A) Intrusive. B) Metamorphic. C) Lava. D) Pyroclastics. E) Magma.

C) Lava.

25) A rock transformed from any other rock through extreme heat and/or pressure is referred to as: A) Ancient. B) Sedimentary. C) Metamorphic. D) Igneous. E) Clastic.

C) Metamorphic.

10) The_________is liquid and is responsible for producing Earth's magnetic field. A) Asthenosphere. B) Mohorovii discontinuity. C) Outer core. D) Lower mantle. E) Inner core.

C) Outer core.

12) At least 90% of Earth's magnetic field is generated by the: A) Inner core. B) Lower mantle. C) Outer core. D) Mohorovii discontinuity. E) Asthenosphere.

C) Outer core.

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART B How do plates move at convergent plate boundaries? A) Plates move apart. B) Plates move side by side. C) Plates move together. D) Plates do not move.

C) Plates move together.

14) The continuous alteration of Earth materials from one rock type to another is known as the: A) Biogeochemical cycle. B) Hydrologic cycle. C) Rock cycle. D) Geologic cycle. E) Tectonic cycle.

C) Rock cycle.

29) The______drives the endogenic processes of the rock cycle. A) Rock cycle. B) Hydrologic cycle. C) Tectonic cycle. D) Atmospheric circulation. E) Biogeochemical cycle.

C) Tectonic cycle.

33) Which of the following are located along the mid-ocean ridges? A) Evaporite deposits. B) Seamounts. C) Volcanoes. D) Old oceanic sediments. E) Outcrops of granite.

C) Volcanoes.

8) Knowledge of Earth's interior is mostly derived from: A) Work in Earth's deepest caverns and caves. B) Historic & prehistoric records. C) Analysis of exposed materials from geologic uplifting events & volcanic eruptions. D) Indirect evidence involving the analysis of seismic waves. E) Direct sampling of the interior using deep-test wells.

D) Indirect evidence involving the analysis of seismic waves.

13) Geomagnetic reversals: A) Cause in mass species extinctions due to increased cosmic radiation. B) Are caused by rapid tectonic movement. C) Are predictable events, occurring at set intervals of 100,000 years. D) Involve slow diminishments to low intensity & a rapid regaining of full strength. E) Are rapid events in which the magnetic field "blinks" off and on again.

D) Involve slow diminishments to low intensity & a rapid regaining of full strength.

11) The rigid crust and uppermost mantle are known collectively as the: A) Gutenberg discontinuity. B) Moho. C) Asthenosphere. D) Lithosphere. E) Rigid layer.

D) Lithosphere.

32) _______is the coherent theory that describes the motion of the Earth's lithosphere & associated processes & results. A) Pangaea. B) Contact metamorphism. C) Sea floor spreading. D) Plate tectonics. E) Metamorphism.

D) Plate tectonics.

38) Mid-ocean ridges occur where: A) The geographic middle of an ocean basic occurs. B) At ocean-continent margins. C) Plates are converging. D) Plates are moving apart (diverging). E) Plates are sliding past one another (transform boundaries).

D) Plates are moving apart (diverging).

42) ANIMATION: MOTION AT PLATE BOUNDARIES PART C How do plates move at transform plate boundaries? A) Plates do not move. B) Plates move apart. C) Plates move together. D) Plates move side by side.

D) Plates move side by side.

23) If you were driving down the highway and saw mountains composed of layered strata, you could be confident that you were looking at: A) Extrusive igneous rocks. B) A shield volcano. C) Intrusive igneous rocks. D) Sedimentary rocks. E) Batholiths or laccoliths.

D) Sedimentary rocks.

63) Pulverized rock & clastic materials ejected violently during an eruption are called: A) Volcanic ash. B) Cinders. C) Scoria. D) Tephra, or pyroclastics. E) Explosive debris.

D) Tephra, or pyroclastics.

2) Which of the following is an exogenic process? A) Volcanism. B) Earthquakes. C) Flows of heat & materials in the mantle. D) Weathering. E) Radioactive decay.

D) Weathering.

9) Earth's interior is layered because: A) Successive subduction events at convergent plate boundaries forcing earthen materials downward. B) Centrifugal force separated out the materials based on weight as the Earth solidified. C) The planet was formed due to successive bombardments of cosmic debris. D) Materials became sorted based on electromagnetic fields as the Earth solidified. E) Materials became sorted based on density as the Earth solidified.

E) Materials became sorted based on density as the Earth solidified.

37) Along________, new ocean floor is formed by upwelling flows of magma, whereas along______, old oceanic crust is destroyed. A) Subduction zones; mid-ocean ridges. B) Archipelagos; oceanic trenches. C) Oceanic trenches; archipelagos. D) Seamounts; mid-ocean ridges. E) Mid-ocean ridges; subduction zones.

E) Mid-ocean ridges; subduction zones.

26) Metamorphism that occurs over broad areas when the pressure & associated heat of overlaying rocks or other tectonic forces cause the rocks to undergo deformation is known as: A) Clastic metamorphism. B) Contact metamorphism. C) Extrusive metamorphism. D) Intrusive metamorphism. E) Regional metamorphism.

E) Regional metamorphism.

35) Ocean floor subducts under continents because: A) The ocean floor has a lower density and therefore sinks more easily. B) Granite is denser than basalt, forcing the basaltic ocean floors downward. C) The ocean floor is made of felsic minerals & is heavier than continental material. D) The weight of the continents is so great that they push the ocean floor material downward. E) The ocean floor is made of mafic material & is therefore more dense than continental material.

E) The ocean floor is made of mafic material & is therefore more dense than continental material.

1) Which of the following is an endogenic process? A) Wind erosion. B) Stream deposition. C) Glacial erosion. D) Weathering. E) Volcanism.

E) Volcanism.