Oce 1001 chapter 4

Biogenous sediments are indicated by the number(s):

2, 3, & 4.

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

3 miles

Calcareous oozes are represented by the number(s):

4

What do freeze-thaw and salt weathering have in common?

BOTH freeze-thaw and salt weathering require rain and force rocks apart physically

Why does calcareous material dissolve below the CCD?

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

Of the following sediments, which one(s) is/are considered hydrogenous?

COATINGS of metal sulfides near black smokers MANGANESE nodules

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

Under what conditions will the front of a glacier remain stationary?

Glacial fronts remain stationary when melting and snow accumulation are EQUAL

Pelagic clays contain lots of material that settles to the seafloor through the water column and are:

LESS than 30% BIOGENIUS material.

Which of the following contains silica (SiO2)?

Radiolarians

Neritic sediments are most likely to be composed of

Sand, silt, and gravel

Which of the following conditions allows for calcareous ooze to be found beneath the CCD? Select only one answer.

THE OOZE ACCUMULATES above the CCD and then is covered before being transported to deeper depths by sea floor spreading.

What can you infer about the ocean environment from a core sample composed of the following layers: 1. siliceous ooze (youngest layer) 2. calcareous ooze 3. basalt rock (oldest layer)

The core was collected in a region of HIGH SURFACE PRODUCTIVITY in water deeper than 4,500 meters.

What is salt weathering?

The formation of MINERALS in rock cracks during the EVAPORATION of salty water, forcing rock apart

How would you expect the front of a glacier to move if it undergoes a period of net accumulation, followed by net wastage, and finally a period of net accumulation?

The glacier's front would move FORWARD BACKWARD FORWARD

What do manganese nodules, metal sulfides, and evaporites all have in common?

They all PRECIPITATE from water oversaturated in their respective minerals

Why does water frozen in the cracks of a rock help to break down the rock?

Water EXPANDS when frozen and PHYSICALLY forces the rock apart.

What is calcareous ooze?

a FINE-grained, DEEP ocean sediment containing the skeletal remains of CALCITE-secreting microbes

Sediments that are poorly sorted were most likely deposited by:

a glacier

As a whole, the pH of surface waters of the ocean is slightly __________.

alkaline

What common household item is used in this video to demonstrate rotary drilling?

an apple corer

Ice Rafting

associated with glacial deposits

Why is this drilling process called rotary drilling?

because the drill bit turns around in a circle

What are the three types of loads carried by streams?

bed load, suspended load, dissolved load

coccolithophores

biogenous sediment

identify the word and/or phrase that does NOT fit the pattern A. biogenous B. calcareous C. cosmogenous D. hydrogenous E. lithogenous

calcareous

The depth at which calcite dissolves rapidly in the ocean is called the __________.

calcite compensation depth OR CCD

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

calcium carbonate

Carbon dioxide (CO2) combines with water (H2O) to form __________.

carbonic acid

The presence of what type of macroscopic sediment would provide evidence of a meteorite impact on Earth?

chondrites

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

clathrates

Complete this analogy: Bouncing is to sand as suspension is to____

clay

What have oceanographers determined from analyzing sea floor cores?

climate change and past extinctions

Ocean sediments provide all the following mineral resources except

coal

Which of the following are microscopic, single-celled floating algae that accumulate to form biogenous sediment Diatoms/Foraminifers/Coccolithophores

coccolithophores & Diatoms

Calcite-secreting organisms such as __________ and __________ live in the ocean's sunlit surface waters and form the basis of most marine food webs.

coccolithophores; foraminifers

You add sand, silt, and clay to a jar of water, shake the jar vigorously, and allow the sediment to settle. The resulting sediment will most closely resemble that of a(n) __________.

continental rise

Sediments with an extraterrestrial origin are called:

cosmogenous

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

CCD

depth at which ALL calcium carbonate is in solution (i.e. dissolved)

All the following are examples of lithogenous sediment except : glacial deposits/beach sand./volcanic particles./clays./diatom ooze.

diaton ooze

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 way does ice flow in a glacier retreating uphill?

downslope

Calcareous ooze is found in cooler waters at depth around the world.

false

Macroscopic biogenous sediment is the most abundant biogenous sediment in the marine environment.

false

Sediments derived from weathered rock and volcanic activities are called biogenous sediments.

false

The pH scale is a measure of the __________ ion concentration of a solution.

hydrogen

manganese nodules

hydrogenous sediment

metal sulfides

hydrogenous sediment

Phosphate-rich nodules form in:

intermediate to shallow depth water

Complete this analogy: Sliding is to gravel as dissolution is to_____

ions

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

lithogenous

abyssal clay

lithogenous (terrigenous) sediment

Calcium carbonate is most likely to dissolve in water with which characteristic?

low salinity

All the following statements are true of ocean sediments except :

ocean sediments are THICKEST in pelagic waters overlying the oceanic ridges.

Of the following environments, where would you expect to find large amounts of lithogenous sediment? on the continental slope/along the mid-ocean ridge/on the continental shelf/in deep trenches not far offshore/on coral reefs that exist just below the water surface

on the continental shelf/in deep trenches not far offshore

identify the word and/or phrase that does NOT fit the pattern. A. coccolithophores B. diatoms C. foraminiferans D. oolites E. radiolarians

oolites

Marine sediment with more than 30% biogenous material is called

ooze

Wentworth Scale

particle size classification

The most abundant mineral in lithogenous sediments is __________.

quartz

Which of the following organisms are responsible for the creation of siliceous ooze? Radiolarians/Coccolithophores/Diatoms/Foraminifers

radiolarians & diatoms

How can pieces of rock in contact with a stream bed move?

rolling, sliding, bouncing

Sediment samples from deep beneath the ocean floor are recovered by __________.

rotary drilling

Which of the following are part of the bed load? sand/clay/gravel/ions

sand/gravel

identify the word and/or phrase that does NOT fit the pattern. A. siliceous ooze B. quartz sand C. rock fragments D. clay E. volcanic ash

siliceous ooze

All the following are examples of hydrogenous sediment except :

stromalites

identify the word and/or phrase that does NOT fit the pattern. A. halite and other salts B. manganese nodules C. metal sulfides D. phosphates E. tektites

tekites

In the demonstration, what does the apple represent?

the deep sea floor

What is suspended load?

the fine-grained particles that travel in the water column above the stream bed

Which is the best definition of glacial snow line?

the line dividing zones of ACCUMULATION and melting of ice at the surface of a glacier

What is the calcite compensation depth, or CCD?

the ocean depth BELOW which calcite is UNSTABLE and will dissolve quickly

How would a snow line on a glacier move as a glacial front is advancing?

the snow line would move DOWN SLOPE

Calcareous shells generally will not accumulate on the ocean floor when the water depth exceeds about 4,500 meters (around 15,000 feet).

true

Calcium carbonate, phosphates, and manganese may precipitate out of solution to form deposits on the ocean floor.

true

Organisms that live on the ocean floor may be responsible for keeping manganese nodules from being buried in the sediment.

true

Texture refers to the size and shape of sediment particles.

true

The organisms that contribute to biogenous sediment are chiefly algae and protozoans.

true