Oceanography Ch. 3

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern.

Rift valley

Which of the following techniques used to determine ocean bathymetry is illustrated in the image?

Side-scan Sonar

The first recorded attempt to measure the ocean's depth was conducted using which of the following techniques?

Sounding

Which of the following is the predominant process that forms the thick blanket of sediment on abyssal plains the deep-ocean floor?

Suspension settling

Judge the following sentence according to the criteria given below: Multibeam SONAR systems have resolution limitations in deep water BECAUSE beams of sound spread out with depth.

The assertion and the reason are both correct, and the reason is valid.

Characteristics of passive continental margins include which of the following?

Broad continental shelves

Passive margins are usually produced over geologic time by which of the following?

Continental rifting and continued sea floor spreading

Active continental margins are characterized by which of the following?

Deep-sea trenches

What is a linear sea floor feature that is seismically inactive, occurs beyond offset mid-ocean ridge segments, and the relative movement between two points on either side of the feature is in the same direction?

Fracture zone

Which of the following features is related to transform faults along mid-ocean ridges?

Fracture zone

The distinctive type of sedimentary layering that has largest particles on the bottom and smallest particles on the top, with intermediate sized particles in the middle, is called which of the following?

Graded Bedding

To which planet is NASA sending the spacecraft InSight to study crustal movements similar to earthquakes

Mars

Which of the following techniques used to determine ocean bathymetry is illustrated in the image?

Multibeam Sonar

Why is the average depth of the ocean much greater than the average height of land?

Oceanic crust is more dense than continental crust.

Tamu Massif, the largest single volcano on Earth occurs in which of the following oceans?

Pacific Ocean

Judge the following sentence according to the criteria given below: Few abyssal plains are located in the Pacific Ocean BECAUSE turbidity currents only occur along passive continental margins.

The assertion is correct, but the reason is incorrect.

Judge the following sentence according to the criteria given below: The Pacific Ring of Fire is home to the majority of Earth's active volcanoes and large earthquakes BECAUSE of the prevalence of divergent plate boundaries along the Pacific Rim.

The assertion is correct, but the reason is incorrect.

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern.

Trenches

What effect do turbidity currents have on the continental slope?

Turbidity currents are erosive to the continental slope and, as a result, carve out submarine canyons

The average slope of the continental shelf is approximately ________.

a tenth of a degree

Of the following items, which is/are associated with a passive continental margin? Choose all that apply.

a wide continental shelf a continental rise

Volcanic features on the ocean floor that are less than 1,000 meters (0.6 miles) tall are called:

abyssal hills or seaknolls.

Extending from the base of the continental rises into the deep-ocean basins are flat depositional surfaces called:

abyssal plains.

The measurement of ocean depth and the charting of seafloor topography is called ______

bathymetry

Satellites use microwave beams to measure sea level to an accuracy of four ________.

centimeters

What features are associated with a passive continental margin?

continental rise;flat coastal terrain

Older lithosphere is destroyed in association with:

deep-sea trenches.

What is the characteristic layering of an individual turbidity current deposit called?

graded bedding

Volcanic peaks that are below sea level but rise more than 1 kilometer above the deep-ocean floor and have a flattened top are called ________.

guyots

The direction of motion along a seafloor transform fault is:

in the same direction as the plates are spreading.

Volcanic peaks on the deep-ocean floor with conical tops are called:

seamounts

What is turbidity?

suspended sediment

Satellites are used to map the ocean floor because _______

the shape of the ocean surface reflects large features on the seafloor

Along the margins of the Pacific are found most of Earth's:

oceanic trenches.

With respect to mid-ocean ridges, transform faults are:

perpendicular to the ridge axis.

Most large ocean floor features owe their origins to ______

plate tectonic processes

Warm water (From 30°C to 350°C) hydrothermal vents form:

white smokers.

The greatest proportion of Earth's surface lies in this elevation/depth interval.

4,000 - 5,000 m below sea level

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?

5,550 meters Remember that the sound has to travel down and back.

What percent of Earth's volcanic activity, each year, takes place on the seafloor?

85%

Where does the deep-ocean basin begin along a passive continental margin?

Continental slope

Which of the following is a difference between passive and active continental margins?

Convergent active margins will have a steep continental slope, whereas passive margins will have a more gradual slope

Which part of Earth's cumulative hypsographic curve includes the mid-ocean ridges?

The shallowest slope below sea level

Which of the following best describes turbidity currents?

Underwater avalanches of muddy water mixed with rocks and other debris

The island of Java is an example of a volcanic island associated with volcanic activity at a ________.

island arc

New lithosphere is produced in association with:

oceanic ridges.

In comparison with other ocean basins, major sedimentary features such as continental rises and abyssal plains are relatively rare in the Pacific. The primary reason for their scarcity in the Pacific is that __________.

sediment is trapped within the trenches of the convergent plate boundaries ringing the Pacific

The reason the deposit on the bottom forms the way it does is a result of _________

settling velocity

The correct order of seafloor features from the coast to the mid-ocean ridge is:

shelf, slope, rise, abyssal plain.

The method that is used most frequently to investigate sediment and rock layers of the sea floor is

sound waves (specifically seismic reflecting profiling)

All true oceanic islands are ________ in origin.

volcanic

Seamounts and abyssal hills are ________ in origin.

volcanic

Which of the following feature(s) is/are associated with the mid-ocean ridge?

volcanoes; a central rift valley; basalt volcanism and pillow lavas; hydrothermal vents

Which of the following is an example of an active continental margin?

west coast of Chile and west coast of U.S