Physical Geology
Volcanoes formed as a result of oceanic crust subduction are enriched in which of the following two elements, compared to the upper mantle? A iron and oxygen B silicon and oxygen C iron and magnesium D silicon and nickel E oxygen and nickel
B
What did Wegener name the supercontinent, or the mass of land that existed before continents drifted? A Panga B Pangaea C Paengae D Pengaea
B
The sediment that accretes on oceanic crust can only ever reach a maximum thickness of about 50 meters.
False
___ is the force applied to plates at spreading centers. a. inertia b. ridge push c. convection d. slab pull
Ridge Push
What do geologists call the action that tears open the crust of the lithosphere at a divergent boundary?
Rifting
The formal term that describes the events that occurred after Earth passed iron's melting point is chemical differentiation.
True
The type of rock found at two converging plates is an important factor controlling what happens at the boundary between them.
True
Transform boundaries are characterized by frequent earthquakes.
True
When continental crust collides with another continental crust, not only do mountains form but the crust forms roots, in a sense. This is really just the crust sinking under the weight of the mountains.
True
Plates have what three types of boundaries?
divergent, convergent, and transform
Three plate boundaries, defined by relative motion, are: (Select all that apply.) A Lateral B Spreading center C Transform D Converging E Diverging F Convergent G Divergent H Strike slip I Hotspot
divergent, convergent, and transform
About 81% of the world's largest earthquakes occur:
in the circum-Pacific seismic belt sample.
Subduction zones usually occur very close to spreading centers.
False
Approximately how much of Earth's mass sank to the center of the planet during the iron catastrophe?
1/3
How many major plates have been identified?
12
What temperature is Earth's core?
5000 C
What percent of Earth's core is composed of iron
90%
At ocean-ocean convergent boundaries: A Older, more dense crust tends to subduct beneath younger, less dense crust. B Younger, less dense crust tends to subduct. C There are rarely earthquakes. D Island arcs tend to subduct. E Transform faults typically will develop.
A
At the San Andreas transform fault, A The Pacific Plate moves to the north relative to the North American Plate. B Lithosphere is subducted as one plate dives below another. C New lithosphere is formed as two plates pull away from each other. D Pressure-release melting recycles old crust.
A
During the Hadean Eon, which of the following is thought to have occurred? A The iron catastrophe. B Origin of life on Earth. C Formation of modern continents. D Growth of the modern seas.
A
How does the chemical differentiation of Earth today reflect the influence of the iron catastrophe? A There is more iron in the core than in the crust. B The lower lithosphere stores most of Earth's iron. C Iron is rare in Earth. D Much of Earth's iron has escaped as a result of extraterrestrial impacts.
A
Magnetic reversals are caused by: A Unknown causes. B Faster subduction rates across Earth. C Lunar gravitational effects. D Changes in the rate at which Earth orbits the Sun. E Impacts of extraterrestrial objects.
A
Oceanic crust: A Is enriched in iron and magnesium compared to continental crust. B Is made of metamorphic rock. C Is formed by asteroid impact. D Forms from sea salt.
A
The seafloor sinks as it moves further away from the rift zone, because it becomes ___ as it cools. a. more dense b. less dense c. darker in color d. lighter in color
A
What are the principal differences between the average chemistry of the crust and the average chemistry of Earth as a whole? A Earth as a whole has a greater relative abundance of silicon than does the crust. B The crust is relatively enriched in magnesium and relatively depleted in oxygen. C The crust contains a greater relative abundance of heavier elements than does Earth as a whole. D Earth as a whole has a greater abundance of silicon than does the crust.
A
What must always precede a continent-continent collision? A Ocean and continent must converge. B Ocean and ocean must converge. C The poles must have recently switched. D A major earthquake must occur. E The Mid-Atlantic Ridge must be particularly active.
A
What zone experiences the most volcanoes and earthquakes on Earth? A the Ring of Fire B the Circle of Destruction C the Ring of Death D the Circle of Fire E the Sphere of Fatalities
A
Which nation was struck by a major earthquake on January 10, 2010, leaving 230,000 or more people dead and 1 million more homeless? A Haiti B Puerto Rico C Chile D China E Japan
A
Which plate movement mechanism depends on the gravitational slope from the crest of oceanic ridges all the way down to the base of deep-sea trenches to help pull the plate downhill and ultimately subduct it? A the ridge slide mechanism B the crest to base mechanism C the trenching mechanism D the gravitational subduction mechanism E the sloping mechanism
A
A hypothesis must be testable so that: (Select all that apply.) A It can be objectively evaluated. B Its accuracy can be independently assessed. C It is possible to revise the hypothesis if it does not provide accurate predictions. D Its viability to make accurate predictions can be appraised.
ALL
Mantle convection: (Select all that apply.) A Was proposed by Hess as the driver of seafloor movement. B Is the product of heat flow within Earth's interior. C Causes rifting and seafloor movement between spreading centers and subduction zones. D Is thought to resemble the action in a lava lamp.
ALL
Subduction occurs: (Select all that apply.) A When a plate enters the mantle at a deep sea trench. B When a plate is recycled into Earth's interior. C When seafloor is recycled beneath an overriding plate. D When one plate slides beneath another.
ALL
The process of seafloor spreading predicts that: (Select all that apply.) A Seafloor moves like a conveyor belt from spreading centers toward subduction zones. B The oldest seafloor will be found at subduction zones. C There is high heat flow from Earth's interior into the crust at spreading centers. D Continents shift locations because they are embedded in moving plates.
ALL
Earthquakes occur at: (Select all that apply.) A Divergent plate boundaries. B Transform boundaries. C Ocean-continent plate boundaries. D Ocean-ocean convergent plate boundaries.
All
Which of the following geological features on Earth's surface exist because of plate tectonics?
All
Which period of geologic time immediately followed the Hadean era?
Archean Era
Earth's great recycling engine, perpetually renewing and destroying rock and ultimately providing humans with critically important natural resources, is called: A paleomagnetism. B the rock cycle. C plate tectonics. D chemical differentiation E orogenesis.
B
Earth's plates ride on circulating currents of hot rock. This process moves the plates and is the product of ________________. A conduction B convection C conveyance D transposition E reversion
B
Mountain building resulting from continent-continent collision is known as: A subduction B orogenesis C the mid-oceanic ridge D paleomagnetism E a passive margin
B
Sediment cover _______ fitter away from the MOR. a. decreases b. increases
B
Subduction occurs: A During orogenesis. B When a plate enters the inner core. C When a continent is recycled beneath an overriding plate. D When a lithospheric plate is recycled into Earth's interior. E When one plate crashes into another.
B
The Himalayan Mountains are an example of: A A subduction zone. B Continent-continent convergence. C Extraterrestrial impact. D Continent-ocean convergence.
B
The conclusions from a study are only as good as the __________ is/are. A presentation B tests C All of the choices are correct. D location E financial backers
B
Three types of convergent boundaries exist. What are they called? A desert-mountain, ocean-island, valley-mountain B ocean-ocean, continent-ocean, continent-continent C valley-sea, mountain-sea, desert, sea D None of the choices are correct. E mountain-sea, sea-sea, mountain-mountain
B
Which is the correct order of the layers of the interior of the Earth from the surface to the center. a. asthenosphere, lower mantle, lithosphere, outer core, inner core b. lithosphere, asthenosphere, lower mantle, outer core, inner core c. asthenosphere, lithosphere, lower mantle, outer core, inner core d. lower mantle, asthenosphere, lithosphere, outer core, inner core e. lithosphere, lower mantle, asthenosphere, outer core, inner core
B
Who was the one man responsible for the development of the theory of plate tectonics? A J. Tuzo Wilson B Harry Hess C None of the choices are correct. D an unknown German scientist E Alfred Wegener
B
A mudslide that occurred in 1983 killed 25,000 people. It was a volcanic eruption that incited the mudslide disaster. In which South American country did this happen? A Chile B Paraguay C Colombia D Peru E Bolivia
C
Complete the following sentence. The older oceanic crust is, _____________________. A the less sediment will cover it B the more iron it contains C the more sediment will cover it D the more likely it is that it will soon transform into continental crust E the more silicon it contains
C
Evidence that the polarity of Earth's geomagnetic field has reversed in the past is found: A Where magma develops above a subducting slab. B In accretionary prisms. C In magnetic reversals recorded by iron minerals in oceanic crust. D In magnetic striping in volcanic arcs.
C
In 1883, Krakatau volcano erupted, causing a tsunami. Between the tsunami and the eruption, 37,000 people lost their lives. In which country is this volcano located? A China B Nicaragua C Indonesia D Columbia E Haiti
C
The rock cycle is a concept that: A Has no relationship to plate tectonics. B Was first described only two decades ago. C Describes the recycling of rock. D Is not a well-accepted hypothesis.
C
Which landform is generally not an indicator for the existence of a transform boundary? A offset ridges B linear valleys C mountains D zigzagging stream valleys that run along the plate boundary E long, groundwater-filled lakes
C
Which layer is the least dense a. upper mantle b. asthenosphere c. crust d. outer core e. lower mantle f. inner core
C
Darwin's studies of evolution are now considered A inconclusive. B a hypothesis. C natural law. D a theory. E a fact.
D
Hess's mechanism for moving plates was: A Continental drift. B Volcanic eruptions. C Ocean currents. D Mantle convection.
D
How is Earth organized? A Earth has an inner mantle and an outer lithosphere, with a liquid inner core. B Earth's crust rests atop the liquid mantle and the solid outer core. C The inner core is solid, the mantle is solid, and the crust is solid under the continents and liquid under the oceans. D Earth has an inner and outer core, a mantle, and a crust.
D
What caused the layers of the Earth to form? a. Physical regulation b. Substitution c. Deportation d. Chemical differentiation
D
Which of the following components are involved in the rock cycle? A biosphere B crust C mantle D All of the choices are correct. E hydrosphere
D
Which of the following men was responsible for the rock cycle concept? A Charles Darwin B Nicolas Steno C Sir Charles Lyell D James Hutton E William Smith
D
How long is it estimated that it will take for Los Angeles to be adjacent to San Francisco? A 1 million years B 100 million years C 50 million years D 110 million years E 10 million years
E
Physical Geology is the study of: A None of the choices are correct. B Fossils and past environments. C The nature of how humans and animals interact and influence one another. D The history of life on Earth. E The materials that compose Earth and the ways in which they are organized and distributed throughout the planet.
E
The laws of thermodynamics are considered ________. A hypotheses B theories C facts D outdated E natural laws
E
The subdivisions of the geologic time scale that represent the greatest expanse of time are called: A Periods. B Eternity. C Epochs. D Eras. E Eons.
E
Transform faults take part in a type of motion called: A severing. B splitting. C cleaving. D fragmenting. E shearing.
E
What geophysicist first proposed that a transform boundary is the connecter between two spreading centers? A Luis Walter Alvarez B Samuel Tolansky C Hannes Olof Gösta Alfvén D Herbert L. Anderson E J. Tuzo Wilson
E
An educated guess that has passed repeated testing becomes a hypothesis.
False
As water flows upward off of a subducted plate, it causes the melting point of rock in the upper mantle to go up, thus slowing the rate at which rock melts into magma.
False
Captain Harry Hess of Princeton University introduced a new concept to the scientific community during World War II. He produced evidence obtained from seafloor mapping that proved the ocean floor was indeed flat and featureless.
False
Compulsion-release melting melts rock and creates magma, which then fills in the existent gap in the lithosphere at a divergent boundary.
False
Continental crust always subducts under oceanic crust.
False
During Earth's formation, nickel and silicon were lighter than iron so they flowed toward Earth's surface.
False
Earth's magnetic poles are fixed and have not wandered from their current location in all of Earth's history.
False
Earth's magnetic poles emerge from the planet's surface exactly where its rotational axis exists.
False
Earthquakes and volcanic eruptions always occur along plate boundaries.
False
India and Tibet were once separated by a vast desert before these two countries collided and formed the Himalayas.
False
Most earthquakes occur at divergent plate boundaries.
False
Normal polarity is what geologists call periods in Earth's history when the poles were reverse of what they currently are today.
False
One plate is responsible for moving either continental curst OR oceanic crust. But a single plate cannot move both.
False
Which of the following is not the name of a period of polar reversal in Earth's history? A Brunhes normal B Matuyama reversed C Freichman normal D Gilbert reversed E Gauss normal
Freichman
The thick shell of dense, hot rock that surrounds Earth's core is called the:
Mantle
MOR stands for
Mid-Ocean Ridge
Four major plates are moving away from one another, thus enabling the Atlantic Ocean to open up between them. What are the names of these four plates?
North American, Nubian, South American, and European plates
The three types of convergent plate boundaries are: A Ocean-ocean B Metamorphic C Sedimentary D Subducting E Volcanic F Shearing G Igneous H Divergent I Ocean-continent J Continent-continent K Convergent
Ocean-ocean, Ocean-continent, Continent-continent
Which of the following is not an interaction that occurs along plate boundaries?
Pieces are cooled from the surface.
A very significant event occurred early in Earth's history when the planet's temperature reached, and then went beyond the melting point of iron. What is this even known informally as?
The Iron Catastrophe
From where on Earth does the magnetic field emerge?
The poles
Newly erupted oceanic crust that has emerged from spreading centers displays Earth's magnetic polarity from approximately what period of time? A There is not enough data for geologists to officially hypothesize about this question. B 1,000 years ago C The present D 100 years ago E 50 years ago
The present
An example of a place where paleomagnetism is recorded is in cooling magma at spreading centers
True
Earth has three major layers: core, mantle, and crust
True
Earth's curst can be divided into an oceanic type and a continental type
True
Earth's magnetic field acts as a shield and protects delicate living tissue from solar radiation
True
Earth's outer core (mantle) is thicker than its inner core
True
One hypothesis that geologists have proposed that answers the question "What causes plates to move?" involves convection cells in the upper mantle that actually drag on the underside of plates, inciting movement.
True
Plate tectonics is considered a theory
True
The 2004 Andaman-Sumatra earthquake and tsunami on December 26 left more than 230,000 people dead.
True
The Himalayan, Ural, and Appalachian mountain systems were all formed as a result of a continental crust collision.
True
The Pacific Plate grinds northward along the edge of the North American Plate at a rate of about 6 centimeters a year.
True
Why does the mid-ocean ridge sit higher than the surrounding seafloor?
We know that at a spreading center the lithosphere arcs up, developing a wide bulge on Earth's surface at a mid-ocean ridge. Whether it's pushed up from below, or swollen from the heat escaping the Earth's interior, we don't know for sure.
When two continental crusts converge, what is the resulting landform?
a mountain range
What happens to both subducted and accreted sediments when they are subjected to the pressures at a convergent margin? a. weathering, erosion, and deposition b. melting c. metamorphism
a?
