oceanography chapter 2

Iceland is located on what type of plate boundary? A) Divergent B) Transform C) Continental/continental convergent D) Oceanic/continental E) Oceanic/oceanic convergent

A

What do all plate boundaries have in common? Select only one answer. A) They are all associated with zones of earthquakes. B) They are all located along the edges of continents. C) They occur entirely within the middle of continents. D) They occur only on the ocean floor. E) They are all associated with an abundance of volcanic activity.

A

Compared to the rest of the planet, an unusually high concentration of hot spots and rifting is located on the continent of Africa. A likely explanation for this is that __________. A) the African Plate is essentially stationary with respect to Earth's interior and the thick continental crust acts as a "heat blanket" B) the thick continental crust acts as a "heat blanket" and a large portion of Africa is located near the equator C) mantle plumes do not occur at divergent plate boundaries, and Africa has no divergent plate boundaries D) a large portion of Africa is located near the equator Africa is just very large

A

Consider the geologic fate of the following seamounts and islands in the Hawaiian Island-Emperor Seamount chain. Assuming conditions remain favorable for coral growth, which would most likely be the next to form an atoll? A) Kauai B) Loihi C) Hawaii D) Maui E) Oahu

A

Numerous small, shallow earthquakes tend to occur at __________. A) divergent plate boundaries B) continental/continental convergent plate boundaries C) oceanic/oceanic convergent plate boundaries D) oceanic/continental convergent plate boundaries E) transform plate boundaries

A

Of the following statements about the age of the ocean crust, which one is true? Select only one answer. A) The oldest ocean crust is about 200 million years old and is located near an ocean trench. B) The oldest ocean crust is about 200 million years old and is located near the mid-ocean ridge. C) The oldest ocean crust is about 2 million years old and is located near an ocean trench. D) The oldest ocean crust is about 2 million years old and is located near the mid-ocean ridge. E) The oldest ocean crust is about 4.5 billion years old and is located near the edge of a continent.

A

Of the following statements about ocean crust, which is/are true? Choose all that apply. Hint 1. The processes of seafloor spreading and subduction play an important role in the creation and destruction of oceanic crust. A) Ocean crust is created at the mid-ocean ridge. B) Ocean crust is destroyed at deep-sea trenches. C) Ocean crust is destroyed at the mid-ocean ridge. D) Ocean crust is created at deep-sea trenches. E) Ocean crust is destroyed at transform faults.

A B

Why does the sea floor have a striped pattern of magnetic anomalies that is symmetric with respect to the mid-ocean ridge? Choose all that apply. A) The ocean floor is spreading apart and new sea floor is forming. B) The polarity of Earth's magnetic field experiences reversals. C) The igneous rock of the ocean floor preserves Earth's existing magnetic field as the rock cools. D) Polar reversals cause existing ocean crust to remagnetize. E) Marine organisms that live on the sea floor have caused this pattern.

A B C

Of the following statements about Nemataths and volcanic arcs, which is/are true? Choose all that apply. A) Nemataths and volcanic arcs are both the result of volcanic activity. B) The age of the volcanoes progressively decreases as you move from one end of a volcanic arc to the other. C) In a volcanic arc, any of the volcanoes can be active at any time. D) Volcanic arcs are associated with convergent plate boundaries. E) Volcanic arcs are created at hotspots.

A C D

Of the following statements about Earth's magnetic field, which is/are true? Choose all that apply. A) The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic north pole. B) Magnetic north is at the same point on Earth as the geographic north pole. C) The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic south pole. D) The lines of the magnetic force are parallel with Earth's surface at the equator. E) The magnetic north pole may reverse so that it is located near the geographic south pole.

A C D E

Earthquakes can occur only in the __________. A) crust B) lithosphere C) asthenosphere D) mesosphere E) outer core

B

Which of the following lines of evidence did Alfred Wegener use to support the concept of drifting continents? Choose all that apply. A) the composition of meteors from outer space B) evidence of glaciers in areas that are now tropical C) the pattern of similar mountain belts on different continents D) the way the shapes of the continents fit together like pieces of a jigsaw puzzle E) the distribution of species of fossils

B C D E

Chapter 2 Understanding the Concepts 5 Of the following statements about sea floor magnetic anomalies, which is true? Select only one answer. A) They are oriented perpendicular to deep sea trenches. B) They are oriented parallel to all mountain ranges. C) They are oriented parallel to the mid-ocean ridge. D) They are oriented perpendicular to all mountain ranges. E) They are oriented perpendicular to the mid-ocean ridge.

C

Evidence shows that periodic reversals of Earth's magnetic field have resulted in __________. A) seafloor spreading B) mass extinction of life-forms C) a symmetrical pattern of normal and reverse magnetization in ocean crustal rocks D) interruption of Earth's gravitational field E) apparent polar wandering

C

If the rate and direction of plate movement remain the same for the next 50 million years, an accurate prediction would then be: A) Formation of a land bridge between Australia and Antarctica B) Suturing of the Atlantic Ocean C) Accretion of the California Terrane onto Alaska D) Rifting of the Eurasian plate to form a juvenile ocean E) Subsidence of the Himalayan Mountains

C

Which of the following statements accurately describes a segment of the mid-ocean ridge spreading at a rate of 3 centimeters per year? Choose all that apply. A) It would be classified as an oceanic rise. B) It would create a broad, swollen region symmetrical to the axis of the ridge. C) It would be classified as an oceanic ridge. D) It would have a prominent and deep rift valley. E) It would have few, widely spaced volcanoes associated with it.

C D

A trench and a chain of volcanoes known generally as a volcanic arc are always present where there is __________. A) subduction B) a divergent plate boundary C) a transform plate boundary D) a convergent plate boundary E) a hot spot

D

Which of the following is an example of a nematath? Iceland Great Barrier Reef Mariana Islands Hawaiian Islands-Emperor Seamount Chain Aleutian Islands

D

Which of the following is the main reason that Earth has a magnetic field? Select only one answer. A) Convection of the silicate materials in the asthenosphere generates a magnetic field. B) The solid inner core spins rapidly in the opposite direction as Earth rotates. C) The solid iron-nickel inner core spins rapidly in the same direction as Earth, but much faster. D) Convection in the liquid iron-nickel outer core generates a magnetic field. E) The Sun has such a powerful magnetic field that it creates a magnetic field on Earth.

D

The flat top of a guyot or tablemount in deep water is evidence that __________. A) burrowing organisms have destroyed the peak of the seamount B) the seamount has been submerged by rising sea level that resulted from global climate change C) the seamount is an extinct volcano with the crater filled by a solidified lava lake D) the seamount is an erosional remnant of a flat abyssal plain E) the seamount was once at the surface of the ocean but is now submerged due to plate movement and erosion when it was near sea level

E