Deck 5: Ocean Sediments

Question 1

Most of the floor of the North Pacific Ocean is covered with ____.

A)manganese nodules
B)glacial-marine sediments
C)pelagic clay
D)evaporites

Answer 1

C

Question 2

Neritic sediments are found on the ____.

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

Answer 2

B

Question 3

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

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

Answer 3

D

Question 4

Manganese nodules ____.

A)are a type of cosmogenous sediment
B)are almost exclusively found on continental shelves
C)"grow" very slowly, at an average rate of 1 to 10 millimeters per million years
D)are inexpensive to collect, and are therefore, widely exploited

Question 5

Which particles are the finest in size?

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

Question 6

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 7

Which type of sediment 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

Which type of sediment 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 9

Which of the following are hydrogenous sediments?

A)quartz sand
B)phosphorite deposits
C)siliceous oozes
D)tektites

Question 10

Sediment that contains a mixture of various particle sizes is referred to as ____.

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

Question 11

Which sediments cover the greatest area of seabed?

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

Question 12

Which sediments arrive in the ocean from continents via wind and water?

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

Question 13

Which type of sediment is most abundant in neritic deposits?

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

Question 14

A depression along the boundary of a seamount where sediment has built-up is a(n)____.

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

Question 15

More than 75% of the total ocean floor is considered ____.

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

Question 16

Sand is classified as sediment that has a maximum diameter of ____.

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

Question 17

Sediments that are found on the continental slope and rise and on the deep ocean floor are called ____.

A)pelagic sediments
B)abyssal sediments
C)evaporites
D)neritic sediments

Question 18

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

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

Question 19

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 20

Which method would be valid for classifying sediments?

A)Studying the size and settling rate of sediment grains
B)Studying the thickness of sediment layers
C)Studying the color of the sediment
D)Determining the age of the bedrock underlying the sediments

Question 21

Large volumes of bottom sediments may be transported long distances by ____.

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

Question 22

The depth in the ocean where the rate at which calcareous sediments are supplied to the seabed equals the rate at which those sediments dissolve. What is this depth called?

A)calcium carbonate compensation depth
B)calcium dissolution depth
C)calcium carbonate pressure point
D)carbonate equalization depth

Question 23

Which sediments would be considered oozes?

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

Question 24

Carbonate sediments are rare in deep sea sediments because the ____.

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

Question 25

Some sediment originates from the remnants of organisms.

Question 26

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

Question 27

The study of the ocean's past is referred to as ____.

A)stratigraphy
B)geology
C)paleogeochemistry
D)paleoceanography

Question 28

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

Question 29

Radiolarians and diatoms are both examples of ____.

A)organisms that are only found in tropical parts of the ocean
B)single-celled animals
C)creatures whose shells form siliceous oozes
D)calcareous oozes in the deepest parts of the ocean

Question 30

What type of information can scientists derive from observing deep ocean cores?

A)How much light penetrates the ocean
B)Information about historical changes in Earth's climate
C)Historical changes in tidal cycles
D)Direct measurements of salinity over time

Question 31

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

Question 32

The analysis of layered sedimentary deposits in the ocean is known as ____.

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

Question 33

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 34

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

Question 35

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

Question 36

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

Question 37

An example of a terrigenous sediment is the manganese nodule.

Question 38

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

Question 39

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

Question 40

Aside from manganese, what is the other primary component of manganese nodules?

A)iron oxide
B)uranium
C)silver
D)gold

Question 41

What is the origin of manganese nodules?

Question 42

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?

Question 43

What are the main sources of terrigenous sediments?

Question 44

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

Question 45

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