Deck 2: Plate Tectonics: a Scientific Revolution Unfolds

Question 1

Early results of the Deep Sea Drilling Project clearly justified the conclusion that .

A)Proterozoic rocks are found only as seamounts in the deepest parts of the ocean basins
B)the youngest sediments were deposited directly on the oldest seafloor basalts
C)the oceans have not always contained most of Earth's water
D)the ocean basins are relatively young; most ocean basin rocks and sediments are Cretaceous or younger in age

Answer 1

D

Question 2

Today, _ is in about the same geographic position as during late Paleozoic time.

A)Australia
B)Antarctica
C)India
D)South America

Answer 2

B

Question 3

The modern- day Red Sea is explained by plate tectonics theory because it is .

A)a tiny remnant of a once immense ocean that was closed as Africa moved Asia
B)a rift zone that may eventually open into a major ocean if Arabia and Africa continue to separate
C)the site of a transform fault along which Arabia is moving away from Africa
D)a rare example of a two- continent subduction zone where the African continental plate is sinking under the Arabian continental plate

Answer 3

B

Question 4

Cooler, older, oceanic lithosphere sinks into the mantle at _.

A)transform fault zones along divergent plate boundaries
B)sites of long- lived, hot spot volcanism in the ocean basins
C)rift zones along mid- ocean ridges
D)subduction zones along convergent plate boundaries

Question 5

was an ancient reptile that lived in South America and Africa during the late Paleozoic.

A)Mesosaurus
B)Glossopteris
C)Granopteris
D)Monastarious

Question 6

The continental drift hypothesis was rejected primarily because Alfred Wegener could not .

A)identify a mechanism capable of moving continents
B)disprove competing theories that were more accepted by scientists
C)find geologic similarities on different continents
D)all of the above

Question 7

New oceanic crust and lithosphere are formed at .

A)convergent boundaries by submarine eruptions and intrusions of basaltic magma
B)divergent boundaries by submarine eruptions and intrusions of basaltic magma
C)divergent boundaries by submarine eruptions and intrusions of rhyolitic magma
D)convergent boundaries by submarine eruptions and intrusions of rhyolitic magma

Question 8

The is(are)a logical evolutionary analog of the African Rift Valleys ten million years from now.

A)Ural Mountains
B)Red Sea
C)San Andreas fault
D)Peru- Chile trench

Question 9

Which one of the following is an important fundamental assumption underlying the plate tectonic theory?

A)Radioactive decay slows down at the extreme pressures of the inner core.
B)Earth's ocean basins are very old and stable features.
C)Earth's diameter has been essentially constant over time.
D)Earth's magnetic field originates in the outer core.

Question 10

Deep ocean trenches are surficial evidence for .

A)sinking of oceanic lithosphere into the mantle at a subduction zone
B)transform faulting between an oceanic plate and a continental plate
C)rifting beneath a continental plate and the beginning of continental drift
D)rising of hot asthenosphere from deep in the mantle

Question 11

Deep- oceanic trenches are most abundant around the rim of the ocean basin.

A)Pacific
B)Atlantic
C)Arctic
D)Indian

Question 12

Which of the following energy sources is thought to drive the lateral motions of Earth's lithospheric plates?

A)gravitational attractive forces of the Sun and Moon
B)swirling movements of the molten iron particles in the outer core
C)electrical and magnetic fields localized in the inner core
D)export of heat from deep in the mantle to the top of the asthenosphere

Question 13

A typical rate of seafloor spreading in the Atlantic Ocean is .

A)0.1 inches per year
B)2 feet per year
C)20 feet per year
D)2 centimeters per year

Question 14

The late Paleozoic supercontinent is known as .

A)Panatopia
B)Pangaea
C)Pandomonia
D)Pancakea

Question 15

was never proposed as evidence supporting the existence of Pangaea.

A)Islands of Precambrian rocks along the Mid- Atlantic Ridge
B)Similar fossils on different continents
C)Late Paleozoic glacial features
D)Geometrical fit between South America and Africa

Question 16

first related the symmetrical magnetic patterns in seafloor basalts to seafloor spreading at a mid- ocean ridge.

A)Wegener and Wilson
B)Evans and Novak
C)Matthews and Marks
D)Vine and Matthews

Question 17

The temperature below which magnetic material can retain a permanent magnetization is called the .

A)Vine temperature
B)Darcy temperature
C)Bullard point
D)Curie point

Question 18

Pull- apart rift zones are generally associated with a plate boundary.

A)divergent
B)transform
C)convergent
D)all plate boundaries

Question 19

Linear, magnetic patterns associated with mid- ocean ridges are configured as .

A)normal and reversed magnetized strips roughly parallel to the ridge
B)reversed magnetizations along the rift valleys and normal magnetizations along the ridge
C)concentric circles about a rising plume of hot mantle rocks and magma
D)normal and reversed magnetized strips roughly perpendicular to the ridge axis

Question 20

The is an example of an active, continent- continent collision.

A)westward movement of the South American plate over the Nazca plate
B)Arabian Peninsula slamming into North Africa under the Red Sea
C)northern movement of Baja California and a sliver of western California toward the Hawaiian Islands
D)northward movement of India into Eurasia

Question 21

If you could time travel back to the 1920s and meet Alfred Wegener, who was the original proponent of the continental drift hypothesis, what could you tell him about our modern idea of plate tectonics? What would you tell him regarding the structure of the Earth's interior, what evidence exists for plate tectonics, what is the relationship between volcanoes and earthquakes to plate tectonics (specifics), and what are some (if any)of the problems we still have in explaining certain features of plate tectonics?

Question 22

During the first two decades of the twentieth century, was a vigorous proponent of continental drift.

Question 23

The today marks the location of the rift along which Africa separated from South America.

Question 24

A transform plate boundary is characterized by .

A)two converging oceanic plates meeting head- on and piling up into a mid- ocean ridge
B)a divergent boundary where the continental plate changes to an oceanic plate
C)a deep, vertical fault along which two plates slide past one another in opposite directions
D)stratovolcanoes on the edge of a plate and shield volcanoes on the adjacent plate

Question 25

A(n)is a long- lived, stationary magma source deep in the mantle, well below the base of the lithosphere.

Question 26

All of the following are evidence supporting the theory of plate tectonics EXCEPT for .

A)changes in the Moon's orbit due to shifting plates
B)ocean floor drilling
C)paleomagnetism
D)hot spots

Question 27

Rifting and normal faulting are characteristic of a(n)_ plate boundary.

Question 28

In the early part of the twentieth century, argued forcefully for continental drift.

A)Karl Wagner
B)Alfred Wegener
C)Peter Rommel
D)Bill Kohl

Question 29

The San Andreas fault in California is a good example of a(n)plate boundary.

Question 30

Which of the following statements apply to the asthenosphere, but not the lithosphere?

A)deforms mainly by brittle fracturing and faulting
B)zone in the upper mantle that deforms by plastic flowage
C)cool, rigid layer of crust and upper mantle that forms the tectonic plates
D)partial melting of rising granitic plumes produces huge volumes of basaltic magma

Question 31

Which one of the following most accurately describes the volcanoes of the Hawaiian Islands?

A)shield volcanoes fed by a long- lived hot spot below the Pacific lithospheric plate
B)stratovolcanoes associated with a mid- Pacific transform fault
C)shield volcanoes associated with a mid- Pacific ridge and spreading center
D)stratovolcanoes associated with subduction and a convergent plate boundary

Question 32

The volcanoes and deep valleys of east Africa are related to a .

A)continental collision zone between Africa and the Zagros Mountains along the southern margin of Eurasia
B)continental rift along which parts of the African continent are beginning to slowly separate
C)transform fault aligned with the Red Sea carrying the Arabian and African blocks in opposite directions
D)fault allowing Arabia to slip westward past east Africa and penetrate into Turkey

Question 33

The Aleutian Islands occur at a .

A)transform boundary where North America has moved towards Alaska
B)convergent, continental margin with uplifted fault blocks, much like those of the Basin and Range Province
C)convergent boundary on a volcanic arc above a northward- subducting Pacific plate
D)divergent boundary where shield volcanoes are forming

Question 34

Describe exactly what type of plate boundary is illustrated below and explain your answer.

Question 35

Although Alfred Wegener presented compelling evidence for his continental drift hypothesis (despite lacking a mechanism), why was the true nature of plate boundaries not determined until the 1960s?

Question 36

, in the north Atlantic Ocean, is a volcanic island formed over a hot spot on a divergent plate boundary.

Question 37

A very long- lived magma source located deep in the mantle is called a _.

A)hot spot
B)magma welt
C)basalt spout
D)melt well

Question 38

Japan and the Aleutian Islands have formed from a(n)to convergent boundary.