Chapter 4

All of the following are examples of sediment-transporting media EXCEPT ___________. Streams Glaciers Gravity Wind Levitation

Levitation

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

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

False

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

Manganese nodules are a type of foraminifer.

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

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

Which of the following is the most abundant component by weight for deep-ocean sediments? -evaporites -Clay -Sand -gravel -fecal pellets

Clay

Most chalk is made from ___________. Oolites -diatomaceous earth -Coccoliths -Radiolarians -manganese nodules

Coccoliths

Microscopic shells that create biogenous sediment on the sea floor are called ___________. -Smush -Slime -Clays -Nodules -Tests

Tests

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

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

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

abyssal clay

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

along the mid-ocean ridge beneath warm surface waters

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

by turbidity currents

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

calcium carbonate dissolves in seawater

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? -concentration of the particles in fecal pellets. -accumulation in manganese nodules -movement of horizontal ocean currents -transportation by turbidity currents -rain falling in the ocean

concentration of the particles in fecal pellets

Which of the following marine organisms lives in cold, polar waters? -coccolithophores -diatoms -foraminifers -radiolarians

diatoms

In sediments, what does the Wentworth scale describe? -grain color -grain density -grain size -grain shape -grain composition

grain size

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

made of material derived from pre-existing rock material

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

to have it accumulate faster than it dissolves

Calcareous ooze is associated with ________ surface water conditions, and siliceous ooze is associated with ________ surface water conditions. -warm; warm -warm; cool -cool; warm -cool; cool

warm;cool