oceanography chapter 3

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

Suspension settling

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

Transform fault

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

centimeters

Directly seaward of the continental shelf is a more steeply sloping region called the

continental slope

Older lithosphere is destroyed in association with

deep-sea trenches

A tablemount is another name for a(n)

guyot

The Big Island of Hawaii is an example of a volcanic island associated with volcanic activity at a

hotspot

The direction of motion along a seafloor transform fault is

in the same direction as the plates are spreading

Where are the deepest portions of the world's oceans found?

At convergent plate boundaries

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

Continental rifting and continued sea floor spreading

The relief in which of the following regions is similar to that found in mountain ranges on the continents?

Continental slope

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

Continental slope

Which of the following is an example of a passive continental margin?

East Coast of the United States

Which of the following is the standard unit of ocean depth?

Fathom

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

Is a linear sea floor feature that has the following properties a transform fault, a fracture zone, or neither? It is seismically active, it occurs between offset mid-ocean ridge segments, and the relative movement between two points on either side of the feature is in the same direction.

Neither

Is a linear sea floor feature that has the following properties a transform fault, a fracture zone, or neither? It is seismically inactive, it occurs between offset mid-ocean ridge segments, and the relative movement between two points on either side of the feature is in the same direction.

Neither

Deep-ocean trenches and volcanic arcs result from the collision of two plates at convergent plate boundaries and mostly occur along the margins of which of the following oceans?

Pacific Ocean

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

Pacific Ocean

Which of the following is the predominant process that forms the metallic minerals in and around black smokers?

Precipitation

Oceanographers who want to know about ocean structure beneath the sea floor use which of the following techniques?

Seismic Reflection

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

Sounding

Which of the following best describes turbidity currents?

Underwater avalanches of muddy water mixed with rocks and other debris

The average slope of the continental shelf is approximately

a tenth of a degree

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

abyssal hills

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

abyssal plains

Oceanic ridges and rises result from seafloor spreading along

divergent plate boundaries

Submarine canyons were most likely formed by

erosion by turbidity currents

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 two relatively flat areas on the hypsographic curve represent

interior continental areas and abyssal plains on the ocean floor

The island of Honshu is an example of a volcanic island associated with volcanic activity at a

island arc

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

island arc

Ascension Island is an example of a volcanic island associated with volcanic activity at a

mid-ocean ridge

New lithosphere is produced in association with

oceanic ridges

Segments of the oceanic ridge system that are gentler and less rugged in slope due to faster rates of seafloor spreading are called

oceanic rises

The instrument that emits a high-frequency sound beam to measure the depth of the ocean developed in the 1950s is the

precision-depth recorder (PDR)

Volcanic features on the ocean floor that are less than 1000 meters tall are called

seaknolls

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

seamounts

Volcanic peaks that are below sea level but rise more than 1 kilometer above the deep-ocean floor and have a pointy top like an upside-down ice cream cone are called ________.

seamounts

Underwater avalanches of muddy water mixed with rocks and debris are

turbidity currents

All true oceanic islands are ________ in origin.

volcanic

Seamounts and abyssal hills are ________ in origin.

volcanic

Worldwide, scientists estimate that there are about 125,000 known seamounts, many of which originated at ________ centers.

volcanic

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

white smokers

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

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

85%

How many volcanic peaks are known to exist on the Pacific sea floor?

> 20,000

The average slope of the continental shelf is similar to the slope of which of the following?

A large parking lot

Characteristics of passive continental margins include which of the following?

Broad continental shelves

Active continental margins are characterized by which of the following?

Deep-sea trenches

Which part of Earth's cumulative hypsographic curve includes the continental shelves of passive margins?

The shallowest slope below sea level

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

The shallowest slope below sea level

Which part of Earth's cumulative hypsographic curve includes linear scars in the ocean floor, caused by the collision of two plates along convergent plate margins?

The steep deepest part below sea level

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)

Relatively few abyssal plains are located in the Pacific Ocean due to

the presence of convergent active margins

Satellites are used to map the ocean floor because

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