oceanography ch. 4

High-energy environments are most likely to deposit which one of the following?

. large particles such as gravel

Sediments produced by plants and animals in the sea are called:

biogenous.

Micrometeorites are an example of which of the following sediment types?

cosmogenous

A very important way to increase the settling rate of fine particles in the open ocean is via:

fecal pellets

The main energy resources associated with marine sediments are petroleum and ________.

gas hydrates

The number of organisms present in the surface water above the ocean floor is called ________.

productivity

What is the calcite compensation depth, or CCD?

the ocean depth below which calcite is unstable and will dissolve quickly

What factor primarily determines the distribution of radiolarian ooze?

upwelling

What factor primarily controls the distribution of calcareous ooze?

water depth

What is the approximate depth of the calcite compensation depth (CCD) in the ocean?

3 miles (4.5 kilometers)

Why does calcareous material dissolve below the CCD?

Below the CCD, weak acid is formed, which dissolves calcareous material.

Calcareous ooze is an example of which of the following sediment types?

Biogenous Sediment

Siliceous ooze is an example of which of the following sediment types?

Biogenous Sediment

What would happen if the depth of the CCD were above the top of the mid-ocean ridge?

Calcareous ooze would not be found below the CCD.

Of the following, which energy resource(s) can be extracted from marine sediments? Choose all that apply.

Gas hydrates Manganese nodules Phosphorites

Oolites are an example of which of the following sediment types?

Hydrogenous Sediment

Rock salt (halite) is an example of which of the following sediment types?

Hydrogenous Sediment

Abyssal clay is an example of which of the following sediment types?

Lithogenous Sediment

Glacial deposits are an example of which of the following sediment types?

Lithogenous Sediment

Sandstone is an example of which of the following sediment types?

Lithogenous Sediment

Shale is an example of which of the following sediment types?

Lithogenous Sediment

Terrigenous sediment is another name for which of the following?

Lithogenous Sediment

Turbidite deposits are an example of which of the following sediment types?

Lithogenous Sediment

What is calcareous ooze?

a fine-grained, deep ocean sediment containing the skeletal remains of calcite-secreting microbes

The most likely place to find abundant manganese nodules is on the:

abyssal plain far from a continent.

Which of the following are examples of pelagic sediments?

biogenic ooze abyssal clay

Which of the following sediments would you expect to find in a lagoon?

broken bits of coral salt

Which sediment below cannot accumulate below the CCD?

calcareous tests

Marine sediments that originate in the warm tropical surface ocean would create deposits in the deep sea composed primarily of ___________.

calcium carbonate

The sea floor provides the largest reservoir of usable energy in the ocean, and likely the world, in the form of ______________.

clathrates

Of the following types of lithogenous sediment, which one(s) would you expect to find very far from the location of origin? Choose all that apply.

clay, silt, sand

From smallest to largest, which list of sediment particle sizes is in the correct order? (silt, sand, pebbles, clay)

clay, silt, sand, pebbles

What have oceanographers determined from analyzing sea floor cores?

climate change and past extinctions

Which sediment type dominates in the neritic environment?

coarse lithogenous sediment, such as sand and small rocks

Of the following sediments, which one(s) is/are considered hydrogenous? Choose all that apply.

coatings of metal sulfides near black smokers manganese nodules

Sediments with an extraterrestrial origin are called:

cosmogenous

Forams, which are composed of calcium carbonate, __________ above the CCD and __________ below the CCD.

do not dissolve; dissolve

Diatomaceous earth, which is composed of silica, __________ above the CCD and __________ below the CCD.

does not dissolve; does not dissolve

Which of the following contains the most organic carbon on Earth?

gas hydrates

Sediments that are poorly sorted were most likely deposited by:

glacier

Which of the following is a hollow steel tube with a heavy weight on top that is to collect sediment samples?

gravity corer

Sediments produced because of chemical reactions in seawater are called:

hydrogenous.

Sediments derived from pre-existing rocks on land are called:

lithigenous

Which of the following natural gasses is most common in gas hydrates from under the ocean floor?

methane

The ancient remains of which of the following, buried before they could decompose, are the source of today's petroleum deposits?

microscopic organisms

What percentage of the rocks exposed on the continents originated as sedimentary rocks deposited in ancient ocean environments?

more than 50

The type of marine sediment that forms the thickest deposits worldwide is:

neritic, lithogenous sediment deposits.

Where on the ocean floor do abyssal clays develop?

on the deep-ocean floor, far from land

Which of the following is the most advanced technology used to collect sediment samples from the deep ocean?

rotary corer

Neritic sediments are most likely to be composed of __________.

sand, silt, and gravel

What mechanism(s) is/are responsible for transporting clay to deep ocean basins?

slow-moving ocean currents wind

Ocean sediments consist of particles that have slowly settled out of the water by which of the following the processes?

suspension settling

What three steps are required for calcareous ooze to exist below the CCD?

deposition of calcite shells above the CCD, cover of these shells by a non-calcareous material, and movement of the sea floor over millions of years

Collecting adequate samples from which of the following is the most difficult?

deep ocean floor

Marine sediments provide valuable clues about which of the following Earth history events? Choose all that apply.

previous ocean circulation patterns the climate on Earth millions of years ago the ancient geographical locations of ocean basins past catastrophes, such as major extinction events