OCE Ch 3 Questions with Correct Answers (Grade A+)
Question 1: Which of the following statements accurately describe(s) the depth and height of Earth's
surface as shown on the hypsographic curve? The percentage of Earth's surface above sea level is
29.2%. More people have been to the top of the tallest mountain on Earth than have been to the bottom
of the deepest trench. The percentage of Earth's surface represented in the hypsographic curve is
70.8%. The average depth of the ocean is much greater than the average height of land. The tallest
mountain on Earth is taller than the deepest trench is deep.
Answer: The percentage of Earth's surface above sea level is 29.2%. More people have been to the top of
the tallest mountain on Earth than have been to the bottom of the deepest trench. The average depth of the
ocean is much greater than the average height of land.
Question 2: Why is the average depth of the ocean much greater than the average height of land?
Answer: Oceanic crust is more dense than continental crust.
Question 3: Which of the following is an example of an active continental margin? west coast of Africa
east coast of Brazil west coast of the United States west coast of Chile east coast of the United States
Answer: west coast of the United States west coast of Chile
Question 4: What features are associated with a passive continental margin?
Answer: continental rise flat coastal terrain
Question 5: Which of the following is a difference between passive and active continental margins?
Answer: Convergent active margins will have a steep continental slope, whereas passive margins will have
a more gradual slope.
Question 6: What is turbidity?
Answer: suspended sediment
Question 7: What effect do turbidity currents have on the continental slope?
Answer: Turbidity currents are erosive to the continental slope and, as a result, carve out submarine
canyons.
Question 8: The reason the deposit on the bottom forms the way it does is a result of __________.
Answer: settling velocity
Page 1
, Question 9: What is the characteristic layering of an individual turbidity current deposit called?
Answer: graded bedding
Question 10: Hypsographic curve
Answer: cumulative plot of the frequency of depth or elevation
Question 11: Precision-depth recorder (PDR)
Answer: uses high frequency sound waves to measure ocean depth
Question 12: Seismic reflection profile
Answer: used to determine ocean structure beneath the sea floor
Question 13: Bathymetry
Answer: measurement of ocean depth and seafloor topography
Question 14: Multi-beam sonar
Answer: a method of mapping the topography of the ocean floor along a strip up to 60 km wide
Question 15: Satellites are used to map the ocean floor because ________.
Answer: the shape of the ocean surface reflects large features on the seafloor
Question 16: The method that is used most frequently to investigate sediment and rock layers of the sea
floor is:
Answer: sound waves (specifically seismic reflecting profiling).
Question 17: The first recorded attempt to measure the ocean's depth was conducted using which of the
following techniques?
Answer: Sounding
Question 18: A ship's fathometer (an echo sounder) transmits a sound pulse and records the return of
an echo 7.4 seconds later. If the speed of sound in water is 1,500 m/second, what is the water depth in
meters?
Answer: 5500m
Page 2
Question 1: Which of the following statements accurately describe(s) the depth and height of Earth's
surface as shown on the hypsographic curve? The percentage of Earth's surface above sea level is
29.2%. More people have been to the top of the tallest mountain on Earth than have been to the bottom
of the deepest trench. The percentage of Earth's surface represented in the hypsographic curve is
70.8%. The average depth of the ocean is much greater than the average height of land. The tallest
mountain on Earth is taller than the deepest trench is deep.
Answer: The percentage of Earth's surface above sea level is 29.2%. More people have been to the top of
the tallest mountain on Earth than have been to the bottom of the deepest trench. The average depth of the
ocean is much greater than the average height of land.
Question 2: Why is the average depth of the ocean much greater than the average height of land?
Answer: Oceanic crust is more dense than continental crust.
Question 3: Which of the following is an example of an active continental margin? west coast of Africa
east coast of Brazil west coast of the United States west coast of Chile east coast of the United States
Answer: west coast of the United States west coast of Chile
Question 4: What features are associated with a passive continental margin?
Answer: continental rise flat coastal terrain
Question 5: Which of the following is a difference between passive and active continental margins?
Answer: Convergent active margins will have a steep continental slope, whereas passive margins will have
a more gradual slope.
Question 6: What is turbidity?
Answer: suspended sediment
Question 7: What effect do turbidity currents have on the continental slope?
Answer: Turbidity currents are erosive to the continental slope and, as a result, carve out submarine
canyons.
Question 8: The reason the deposit on the bottom forms the way it does is a result of __________.
Answer: settling velocity
Page 1
, Question 9: What is the characteristic layering of an individual turbidity current deposit called?
Answer: graded bedding
Question 10: Hypsographic curve
Answer: cumulative plot of the frequency of depth or elevation
Question 11: Precision-depth recorder (PDR)
Answer: uses high frequency sound waves to measure ocean depth
Question 12: Seismic reflection profile
Answer: used to determine ocean structure beneath the sea floor
Question 13: Bathymetry
Answer: measurement of ocean depth and seafloor topography
Question 14: Multi-beam sonar
Answer: a method of mapping the topography of the ocean floor along a strip up to 60 km wide
Question 15: Satellites are used to map the ocean floor because ________.
Answer: the shape of the ocean surface reflects large features on the seafloor
Question 16: The method that is used most frequently to investigate sediment and rock layers of the sea
floor is:
Answer: sound waves (specifically seismic reflecting profiling).
Question 17: The first recorded attempt to measure the ocean's depth was conducted using which of the
following techniques?
Answer: Sounding
Question 18: A ship's fathometer (an echo sounder) transmits a sound pulse and records the return of
an echo 7.4 seconds later. If the speed of sound in water is 1,500 m/second, what is the water depth in
meters?
Answer: 5500m
Page 2
