Deck 5: Ocean Sediments

Question 1

Which of the following would be considered oozes?

A) Terrigenous sediments.
B) Biogenous sediments.
C) Hydrogenous (or authigenic) sediments.
D) Cosmogenous sediments.

Answer 1

B

Question 2

Sediments that originate in the ocean are called:

A) pelagic sediments.
B) abyssal sediments.
C) biogenous sediments.
D) neritic sediments.

Answer 2

A

Question 3

Large volumes of bottom sediments may be transported long distances by:

A) storm waves.
B) icebergs.
C) tidal action.
D) turbidity currents.

Answer 3

D

Question 4

Select the finest particles in this list.

A) sand
B) silt
C) clay
D) granules

Question 5

Underlying the unconsolidated sediments of the seafloor are:

A) basalt pillows and basement rocks.
B) granite crust.
C) glacial deposits left from the Ice Age.
D) ancient remnants of continental crust.

Question 6

Which of the following are hydrogenous sediments?

A) quartz sand
B) evaporites
C) siliceous oozes
D) tektites

Question 7

Which of the following is of organic origin; i.e., made by organisms?

A) terrigenous sediments
B) biogenous sediments
C) hydrogenous (or authigenic) sediments
D) cosmogenous sediments

Question 8

The oozes on the seafloor mostly consist of:

A) boulders and cobbles from glaciers oozing off the land.
B) bones and teeth of bottom-dwelling fishes.
C) fine muds washed down the continental slope to the seafloor.
D) microscopic hard parts of single-celled living organisms.

Question 9

Carbonate sediments are rare in deep sea sediments because:

A) the organisms providing shells do not live in the deep sea.
B) the abundance of muds and clays cover the carbonate shells.
C) the carbonate shells are dissolved in deep water.
D) the organisms do not live beyond the edge of the continental shelf.

Question 10

Which of the following metals is not usually found in manganese nodules?

A) iron
B) uranium
C) nickel
D) cobalt

Question 11

Radiolarians and diatoms are both examples of:

A) multicellular organisms.
B) single-celled animals.
C) creatures whose shells form siliceous oozes.
D) calcareous oozes in the deepest parts of the ocean.

Question 12

Which of the following is the most abundant sediment in neritic deposits?

A) terrigenous sediments
B) biogenous sediments
C) hydrogenous (or authigenic) sediments
D) cosmogenous sediments

Question 13

Which statement characterizes sediments of the North Pacific?

A) The sediments of the North Pacific are primarily composed of radiolarian deposits.
B) The sediments of the North Pacific are thicker than the sediments of the Atlantic.
C) The sediments of the deep North Pacific are mainly pelagic clays.
D) The sediments of the North Pacific are mostly calcareous oozes.

Question 14

Scientists can derive all of the following types of information from observing deep ocean cores EXCEPT:

A) how much light penetrates the ocean
B) the presence or absence of mineral resources
C) historical water temperatures
D) ancient current patterns.

Question 15

All of the following are valid methods for classifying sediments EXCEPT:

A) the size and settling rate of sediment grains.
B) the thickness of sediment layers.
C) the source material of the sediment.
D) the location on the sea floor where the sediment accumulates.

Question 16

In the process of lithification, sediments:

A) are subducted into the mantle at a deep trench.
B) are converted into solid rock.
C) slip into the center of the mid-ocean ridges and become new seafloor.
D) are uplifted to form the edges of continents.

Question 17

Which of the following arrive in the ocean from continents via rivers?

A) terrigenous sediments
B) biogenous sediments
C) hydrogenous (or authigenic) sediments
D) cosmogenous sediments

Question 18

Most of the floor of the North Pacific Ocean is covered with:

A) manganese nodules.
B) biogenous oozes.
C) red and brown clays.
D) evaporites.

Question 19

Which of the following is generated in place, on the spot where we find them?

A) terrigenous sediments
B) biogenous sediments
C) hydrogenous (or authigenic) sediments
D) cosmogenous sediments

Question 20

Which of the following sediments cover the greatest area of seabed?

A) terrigenous sediments
B) biogenous sediments
C) hydrogenous (or authigenic) sediments
D) cosmogenous sediments

Question 21

Some sediment originates from the remnants of organisms.

Question 22

An example of a terrigenous sediment is the manganese nodule.

Question 23

Sand is classified as sediment that has a diameter no larger than:

A) 4 mm.
B)0.2 mm.
C) 2 mm.
D)0.004 mm.

Question 24

A depression along the boundary of a seamount where sediment has built-up is a:

A) scour moat.
B) guyot.
C) island arc.
D) abyssal plain.

Question 25

Over millions of years, natural gas and oil can be formed from:

A) erosion.
B) volcanic ash.
C) biogenous sediments.
D) terrigenous sediments.

Question 26

Stratigraphy is the study of the deposition and layering of sediments over time.

Question 27

More than 75% of the total ocean floor is considered:

A) continental shelf.
B) deep ocean floor.
C) continental slope.
D) continental rise.

Question 28

The only way in which calcium carbonate sediment can form is by evaporation.

Question 29

Scientists use ocean sediments to obtain information about ocean processes throughout the history of the ocean.

Question 30

Which of the following is a major source of terrigenous sediments?

A) Erosion.
B) Dissolved organic material.
C) Dissolved nutrients.
D) Precipitation over the open ocean.

Question 31

The analysis of layered sedimentary deposits in the ocean is:

A) stratigraphy.
B) oceanography.
C) marine biology.
D) ecology.

Question 32

Clays are the coarsest and most easily transported of the terrigenous sediments.

Question 33

Sediment refers to the inorganic materials that accumulate on the ocean floor.

Question 34

Manganese nodules were discovered during the Challenger expedition and are hydrogenous sediments.

Question 35

An example of a siliceous ooze are those formed from radiolarian shells.

Question 36

The age of most marine sediments is:

A) no older than about 10,000 years old.
B) about 1 million years old.
C) rarely older than about 180 million years old.
D) not possible to determine.

Question 37

One area in the ocean that has an extreme abundance of sediment deposition is:

A) the shallow waters around Alaska.
B) the waters around the tip of Africa.
C) the deep ocean floor in the middle of the Pacific Ocean.
D) the waters near the Gulf Coast of North America.

Question 38

The white cliffs of Dover are chalk-like deposits of coccolithophores and are around 100 million years old.

Question 39

A layer of sediment that contains a mixture of sediments with various sizes is referred to as:

A) homogeneous.
B) poorly sorted.
C) well-sorted.
D) eroding sediments.

Question 40

Neritic sediments are found on the:

A) deep ocean floor mostly in the Atlantic Ocean.
B) continental shelf.
C) continental rise.
D) abyssal plains.

Question 41

Describe neritic sediments and explain what you would expect the composition of a typical neritic sample to be.

Question 42

What are the main sources of terrigenous sediments?

Question 43

What is the origin of manganese nodules?

Question 44

What is sediment and what are the 4 classifications of marine sediments based on their origin?

Question 45

Paleoceanography is the study of past processes and past events that have occurred in the ocean. What types of questions do paleoceanographers ask and what are the methods they use to obtain information about the ocean's past?