OCN 150 Chapter 4

A drill ship used to confirm the existence of seafloor spreading by discovering: -the age of the ocean floor was oldest the farther away from the mid-ocean ridge it was -Sediment thickness increased with distance from the mid-ocean ridge -Earth's magnetic field polarity reversals were recorded in ocean floor rocks

Deep Sea Drilling Project (DSDP)

The calcite compensation depth (CCD) represents the depth where wave action ceases to form calcareous oolites. True/False

False

__________ are protozoans that use an external food source and are found in warmer waters

Formanifers

When sampling sediment, generally every deposit is a mixture of different sediment types. However, different sediment types twnd to dominate and this allows scientists to identify them as lithogeneous, biogeneous, hydrogeneous, or cosmogeneous (True,False)

True

Shallow water on the continental shelf has ________ sediments (neritic/pelagic)

neritic

Pelagic lithogeneous sediment is formed from ___________ ___, wind-blown dust, and fine-grained material transported by deep ocean currents

volcanic ash

Which of the following is the most fine-grained sediment? a) beach sand b) cobbles on the beach c) silt from a quiet lagoon d) a pebble beach e) abyssal clay

e) abyssal clay

_________ ooze is made up of coccolithophores and formanifers

Cacareous

_______ ooze forms under warm surface waters in low latitudes

Calcareous

the ____________________ is where calcite dissolves readily past a certain depth.

Calcite Compensation Depth

What is the correct order of grain size from the Wentworth Scale from smallest to largest?

Clay, Silt, Sand, pebble, Boulder

_________ are photosynthetic algae that form "rock chalk" and are 10-100 times smaller than diatoms. found in warmer waters

Coccolithophores

Where does most of the lithogeneous sediment end up?

Continental Margin

A sediment that is derived from extraterrestrial sources. (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

Cosmogeneous

The skeletal remains (tests) dissolved in sea water at a certian depth that determines the distribution of biogeneous sediment

Destruction

A hydrogeneous sediment that forms when there is restricted open ocean circulation and where evaporative rates are high. They are minerals that form when sea water evaporates

Evaporites

Because they tend to move downslope, most lithogenous sediments are deposited in abyssal plains. True/False

False

Black volcanic beach sand is a type of hydrogenous sediment. True/False

False

A hydrogeneous sediment that are small calcite spheres that have layers like an onion and form in shallow tropical waters where there is a lot of CaCO3. (egg rocks)

Oolites

Sediment that contains quartz sand, quarts silt, clay, volcanic ash, and rock fragments (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

Lithogeneous

the depth in the ocean at which the pressure is high enough and the amount of carbon dioxide in deep ocean waters is great enough to begin dissolving CaCO3

Lysocline

Large enough to be seen without a microscope. Includes shells, bones, and teeth of large organisms. Rare in deep sea

Macroscopic biogeneous sediment

A hydrogeneous marine sediment that is rounded, fist-sized lumps of manganese, iron, adn other metals

Manganese nodules

A hydrogeneous sediment that is associated with hydrothermal vents and are found throughout the ocean floor due to sea floor spreading

Metal Sulfides

Only can be seen under a microscope. More abundant than macroscopic biogeneous sediment. made by microscopic organisms

Microscopic Biogeneos sediment

Naturally occurring compound

Mineral

_______ sediment covers about 1/4 of the sea floor, is in shallow water, is dominantly lithogeneous, and typically deposited quickly. (neritic, pelagic)

Neritic

the build up of tests on the ocean floor

Ooze

Deep water on the abyssal planes has __________ sediments (neritic/pelagic)

Pelagic

________ sediments cover about 3/4 of the sea floor, is found in deeper water, has fine grains, is deposited slowly, and has more biogeneous material. (neritic, pelagic)

Pelagic

A hydrogeneous marine sediment occurs as a coating on rocks and nodules on the continental shelf. They occur beneath area of very high productivity

Phosphates

Sediment that contains a variety of different sized particles are _________ sorted

Poorly

__________ occurs when there is a change in conditions

Precipitation

The number of organisms in the surface water above the ocean floor that determines the distribution of biogeneous sediment

Productivity

Distribution of biogeneous sediment is determined by __________, ____________, and ____________

Productivity, destruction, dilution

What is the most stable, durable, and abundant mineral?

Quartz

__________ are protozoans that use external food, they are often planktonic, and symmetrical. Found in cooler waters.

Radiolarians

eroded particles and fragments of dirt, dust, and other debris that have settled out and accumulated on the ocean floor

Sediments

Which ooze accumulates in areas of high productivity?

Siliceous

________ ooze forms under cool surface waters in high latitudes

Siliceous

_________ ooze is made up of diatoms and radiolarians.

Siliceous

Measure of the uniformity of grain sizes

Sorting

________ and ____ _______ are the two main types of cosmogeneous sediment.

Spherules, meteor debris

Neritic carbonate deposits found in warm, shallow-ocean, high salinity water. They are sedimentary rocks that have fine layers of carbonate and cyanobacteria.

Stromatolites

Which of the following statements about the Deep Sea Drilling Project (DSDP) is FALSE? a) The DSDP drilled to the center of Earth and confirmed that the outer core is composed of liquid iron-nickel material. b) The DSDP confirmed that the age of the ocean floor increases with distance from the axis of the mid-ocean ridge. c) The DSDP confirmed that sediment thickness increases with distance from the axis of the mid-ocean ridge. d) The DSDP confirmed that Earth's magnetic field polarity reversals are recorded in sea floor rocks.

a) The DSDP drilled to the center of Earth and confirmed that the outer core is composed of liquid iron-nickel material.

Populations of microscopic marine organisms in ocean surface waters closely match their abundance in sediments on the ocean floor, even though it takes 10 to 50 years for an individual particle to sink to deep-ocean depths. What accounts for this pattern? a) concentration of the particles in fecal pellets. b) accumulation in manganese nodules c) movement of horizontal ocean currents d) transportation by turbidity currents e) rain falling in the ocean

a) concentration of the particles in fecal pellets.

Lithogenous sediments are ___________. a) made of material derived from pre-existing rock material b) primarily made up of manganese nodules c) derived from outer space d) composed of the hard remains of once-living organisms e)composed of dissolved material from seawater

a) made of material derived from pre-existing rock material

Which of the following is the most abundant component by weight for deep-ocean sediments? a) evaporites b) Clay c) Sand d) gravel e) fecal pellets

b) Clay

How is most sediment transported from the continental shelf out to the continental rise? a) in underwater streams that flow along the sea floor b) by turbidity currents c) by hitching a ride with deep-dwelling marine life d) by sinking far offshore once it gets waterlogged e) through winds

b) by turbidity currents

Which of the following marine organisms lives in cold, polar waters? a) coccolithophores b) diatoms c) foraminiferas d) radiolarians

b) diatoms

Calcareous ooze is associated with ________ surface water conditions, and siliceous ooze is associated with ________ surface water conditions. a) warm; warm b) warm; cool c) cool; warm d) cool; cool

b) warm; cool

Sediments that contains Silica and Calcium Carbonate (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

biogeneou

Sediments that were brought to the ocean by cold surface waters (diatoms and radiolarians), warm surface waters (coccolithophores and formanifers), microscopic shells, and coral reefs (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

biogeneous

What is the second most abundant sediment? (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

biogeneous

Which of the following statements about biogenous oozes is FALSE? a) The organisms that form biogenous oozes live in the sunlit surface waters of the ocean. b) Biogenous oozes include sediments that contain at least 30% CaCO3 tests. c) Biogenous oozes are created by underwater eruptions, which cover the sea floor with fine ash particles. d) Biogenous oozes include sediments that contain at least 30% SiO2 tests. e) Biogenous oozes are composed of the hard remains of once-living organisms.

c) Biogenous oozes are created by underwater eruptions, which cover the sea floor with fine ash particles.

Most chalk is made from ___________. a) Oolites b) diatomaceous earth c) Coccoliths d) Radiolarians e) manganese nodules

c) Coccoliths

Which of the following statements about manganese nodules is FALSE? a) Manganese nodules are a type of hydrogenous sediment. b) Manganese nodules form in layers around a central nucleation object, such as a grain of sand or a shark's tooth. c) Manganese nodules are a type of foraminifera. d) Manganese nodules are thought to precipitate directly from seawater. e) Manganese nodules are composed of oxides of manganese, iron, cobalt, and other metals.

c) Manganese nodules are a type of foraminifera.

In sediments, what does the Wentworth scale describe? a) grain color b) grain density c) grain size d) grain shape e) grain composition

c) grain size

The two most common compouns that make up biogeneous sediment are _________ __________ and ________

calcium carbonate, silica

Sediments brought to the ocean by space dust and meteors (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

cosmogeneous

Sediments that contain iron-nickle spherules, iron-nickle meteorites, and silicate chondrites (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

cosmogeneous

Scientists can locate natural resources like _______ _________ and ________ ____ by studying sediments.

crude oil, natural gas

All of the following are examples of sediment-transporting media EXCEPT ___________. a) Streams b) Glaciers c) Gravity d) Wind e) Levitation

e) Levitation

Where are most modern-day calcareous oozes found in the ocean? a) in deep-ocean trenches b) near hydrothermal vents c) on abyssal plains d) along the mid-ocean ridge beneath warm surface waters e) anywhere beneath cold surface waters

d) along the mid-ocean ridge beneath warm surface waters

Beneath the calcite compensation depth (CCD), ___________. a) organisms with siliceous hard parts cannot live b) the water temperature rises c) abyssal clays cannot form d) calcium carbonate dissolves in seawater e) calcareous oozes are currently forming

d) calcium carbonate dissolves in seawater

The only way for siliceous ooze to be preserved in the ocean is ___________. a) during conditions of high salinity b) for the deposit to be mixed with hydrogenous sediment c) to accumulate above the CCD before it is transported to deeper depths by sea floor spreading d) to have it accumulate faster than it dissolves e) to have slow burial

d) to have it accumulate faster than it dissolves

Sediment maturity ___________ as sorting decreases. (increases,decreases)

decreases

Microscopic shells that create biogenous sediment on the sea floor are called ___________. a) Smush b) Slime c) Clays d) Nodules e) Tests

e) Tests

What lithogeneous neritic deposits are formed from turbidite currents and form graded bedding?

turbidite

_______ are made up of photosynthetic algae and are planktonic, they form light weight white rock. Found in cooler waters

diatoms

the deposition of other sediments decreases the percentage of biogeneous sediments. Determines the distribution of biogeneous sediment.

dilution

Sediments brought to the ocean by precipitating directly from sea water (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

hydrogeneous

Sediments that contain manganese nodules, phosphorite, oolites, metal sulfides, and evaporites (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

hydrogeneous

Which two sediments make up the smaller proportions of marine sediments? (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

hydrogeneous and cosmogeneous

rock particles trapped in glacial ice are carried out to sea by icebergs

ice rafting

Poorly sorted glacial deposits which contains large quantities of clay and poorly rounded grains are ___________. (mature,immature)

immature

Sediment maturity ___________ as clay content decreases. (increases, decreases)

increases

Sediment maturity ___________ as grains become more rounded (increases,decreases)

increases

Sediment maturity ___________ as you eliminate non-quartz material (increases,decreases)

increases

conversion of sediments to rocks by pressure or cementation

lithification

Sediments that were brought to the ocean by wind, rivers, volcanic eruptions, landslides, glaciers, gravity, and turbidity currents (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

lithogeneous

What is the most abundant sediment? (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

lithogeneous

What sediment is most abundant in neritic environments? (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

lithogeneous

_____________ sediment is deposited in bays, lagoons, deep sea ocean basin by turbidity currents (low energy), beaches, and the continental margin (high energy) (lithogeneous, biogeneous, hydrogeneous, cosmogeneous)

lithogeneous

What are the two main origins of the sediments found in the ocean? external _______ material and internal ________ + _________ material

lithogeneous, biogenic, hydrogenic

Well sorted beach sand that contains well rounded and very little clay is considered __________. (mature,immature)

mature

Glacial till and ice-rafted sediments dominate _______ shelves

polar

lithogeneous Continental shelf deposits are know as ________ sediments

relict

Spherules are made of silica and can contain space dust and ________ that are rare evidence of impact events.

tektites

river supplied sands and muds dominate _________ shelves

temperate

What controls the distribution of Sediments on the continental shelf?

tides, waves, and currents

Calcareous biogenic sediments dominate _________ shelves

tropical

Sediment composed primarily of particles the same size are _____ sorted

well