Test 2

Question 1

ocean sediments

Answer 1

solid, mineral or organic in origin; deposits of insoluble particles that have accumulated on the seafloor

Question 2

How are ocean sediments transported?

Answer 2

Water, air, ice then deposited

Question 3

How are rocks transported?

Answer 3

by river and deposited into the sea

Question 4

Size of sediments control the …

Answer 4

erosion (renewal), transport (lateral), deposition

Question 5

What are the different types of erosion occurs in solutions?

Answer 5

evaporation, chemical reactions, organisms

Question 6

What is the size of sediments from biggest to smallest?

Answer 6

boulder, cobbles, pebbles, granules, sand, silt, clay

Question 7

sediment

Answer 7

Loose particles of rock, mineral, or biological material that accumulate on the seafloor or other surfaces, transported and deposited by wind, water, ice, or biological processes.

Question 8

lithogenic sediment

Answer 8

Sediment derived from the weathering and erosion of rocks, typically composed of mineral grains.

Question 9

Terrigenous Sediment

Answer 9

Derived from land sources through weathering, erosion, and transported by rivers, wind, or glaciers to the ocean.

Question 10

Clastic Sediment

Answer 10

Made of fragments of pre-existing rocks or minerals, often carried by water, wind, or ice.

Question 11

Detrital Sediment

Answer 11

Similar to clastic, a broader term that refers to sediment composed of solid particles derived from the breakdown of pre-existing rocks. It includes all clastic sediments but can also include some materials like volcanic ash or mineral grains that are not necessarily transported as solid fragments, consisting of solid particles from weathered rocks.

Question 12

Volcanogenic Sediments

Answer 12

Sediments formed from volcanic activity, including ash, lava fragments, and pumice, often carried into the ocean by wind or water.

Question 13

Cosmogenic Sediments

Answer 13

Sediments originating from space, including micrometeorite dust and tektites, which accumulate slowly on the ocean floor.

Question 14

Biogenic Sediment

Answer 14

Sediment composed of the remains of marine organisms, primarily shells and skeletal material made of calcium carbonate (CaCO₃) or silica (SiO₂).

Question 15

Active Biogenic Sediment

Answer 15

Actively accumulating organic material, often in areas of high biological productivity.

Question 16

Passive Biogenic Sediment

Answer 16

Older, less biologically active material that has settled in deeper ocean areas.

Question 17

Passive Biogenic Sediment

Answer 17

Older, less biologically active material that has settled in deeper ocean areas.

Question 18

Hydrogenic Sediments

Answer 18

Sediments formed from the precipitation of dissolved minerals in seawater, such as manganese nodules, evaporites, and phosphorites.

Question 19

Erosion

Answer 19

The process of breaking down and removing sediments or rock material by water, wind, ice, or gravity.

Question 20

Transportation

Answer 20

The movement of sediment from one place to another by agents like water currents, waves, wind, or ice.

Question 21

Deposition

Answer 21

The process by which transported sediments settle and accumulate in a new location, such as the seafloor.

Question 22

Sorting

Answer 22

The process by which sediments are separated based on size, shape, or density during transportation.

Question 23

Well-Sorted

Answer 23

Sediment composed of particles of a uniform size, typically found in environments with consistent energy conditions, such as beaches or dunes.

Question 24

poorly sorted

Answer 24

Sediment composed of particles of varying sizes, often deposited in environments with fluctuating energy levels, such as glacial or high-energy river settings.

Question 25

Hjulstrom Diagram

Answer 25

A graph that shows the relationship between particle size and the velocity of water needed to erode, transport, or deposit sediments. It helps explain why some fine sediments require higher velocities to erode due to cohesion.

Question 26

Inertia

Answer 26

The resistance of sediment particles to changes in motion. Larger particles have more inertia and require more energy to move.

Question 27

Minimum Velocity to Erode

Answer 27

The lowest water velocity required to lift sediment particles from the seabed and put them into motion.

Question 28

Maximum Velocity to Deposit

Answer 28

The highest velocity at which a moving sediment particle will settle and be deposited rather than remain in suspension.

Question 29

Cohesive

Answer 29

Describes fine-grained sediments, like clay and silt, that stick together due to electrostatic forces, making them harder to erode compared to larger, non-cohesive particles.

Question 30

Settling Velocity

Answer 30

The speed at which a sediment particle falls through water, determined by its size, shape, and density, as well as water viscosity.

Question 31

Lamellar Flow (Laminar Flow)

Answer 31

A smooth, orderly flow of water in parallel layers, with minimal mixing between them. Common in slow-moving water.

Question 32

Turbulent Flow

Answer 32

A chaotic and irregular flow of water with swirling motion and mixing, which enhances sediment transport. Found in fast-moving currents and rivers.

Question 33

Eddies

Answer 33

Swirling currents of water that form within turbulent flow, often causing localized mixing and influencing sediment transport.

Question 34

Fluid Density

Answer 34

The mass of a fluid per unit volume, which affects the ability of water to transport sediment. Higher-density fluids, like seawater, can carry more sediment than freshwater.

Question 35

Solution

Answer 35

A mode of sediment transport where dissolved minerals are carried in water, often contributing to chemical sediment deposition.

Question 36

Suspension

Answer 36

A transport mode in which fine sediment particles (such as silt and clay) are carried within the water column without settling quickly.

Question 37

Saltation

Answer 37

A transport process in which medium-sized sediment particles (such as sand) bounce or skip along the seabed as they are lifted and dropped by water currents.

Question 38

traction

Answer 38

A mode of sediment transport where large particles, such as pebbles and cobbles, are rolled or dragged along the seabed by strong currents.

Question 39

Competency

Answer 39

The maximum particle size that a fluid (such as water) can transport; determined by the velocity and energy of the moving water.

Question 40

Capacity

Answer 40

The total amount of sediment that a fluid can carry at a given time, depending on flow strength and sediment availability.

Question 41

Load

Answer 41

The total amount of sediment transported by a river or ocean current, which can be carried in solution, suspension, saltation, or traction.

Question 42

Flocculation

Answer 42

The process by which fine-grained particles, such as clay, clump together due to chemical interactions (like saltwater mixing with freshwater), increasing their size and causing them to settle faster.

Question 43

Ions

Answer 43

Electrically charged atoms or molecules dissolved in seawater, contributing to chemical sediment formation and ocean salinity.

Question 44

Salts

Answer 44

Compounds formed from the combination of positive and negative ions, such as sodium chloride (NaCl), that contribute to seawater salinity and can precipitate as sediment.

Question 45

Bioagglomeration

Answer 45

The process by which biological activity causes sediment particles to clump together, often forming biogenic sediments or contributing to the formation of oozes.

Question 46

Ice Rafting

Answer 46

The transport of sediments by floating ice (glaciers or icebergs), which later melt and deposit the carried material in the ocean.

Question 47

Productivity

Answer 47

The rate at which marine organisms, such as phytoplankton, produce organic matter, influencing the accumulation of biogenic sediments on the seafloor.

Question 48

Chemical Stability

Answer 48

The tendency of a mineral or compound to remain unchanged under specific environmental conditions, affecting its dissolution or preservation in ocean sediments.

Question 49

Calcite

Answer 49

A mineral form of calcium carbonate (CaCO₃), commonly found in marine sediments and making up the shells of many marine organisms.

Question 50

Aragonite

Answer 50

A less stable, but structurally different, form of calcium carbonate (CaCO₃) compared to calcite, often found in coral skeletons and some mollusk shells.

Question 51

Silica

Answer 51

A mineral composed of silicon dioxide (SiO₂), commonly found in marine sediments from the skeletal remains of diatoms and radiolarians.

Question 52

Apatite (Calcium Phosphate)

Answer 52

A phosphate mineral (Ca₅(PO₄)₃) found in marine sediments, often derived from fish bones, teeth, and other biological sources.

Question 53

Oozes

Answer 53

Deep-sea sediments composed of at least 30% biogenic material, primarily made of silica (from radiolarians and diatoms) or calcium carbonate (from foraminifera and coccolithophores).

Question 54

Aragonite Compensation Depth (ACD)

Answer 54

The depth in the ocean below which aragonite dissolves faster than it accumulates, preventing its long-term preservation in sediments.

Question 55

Calcite Compensation Depth (CCD)

Answer 55

The depth (~4,500 meters) below which calcite dissolves more quickly than it accumulates, preventing carbonate-rich sediments from forming.

Question 56

Silica Compensation Depth (SCD)

Answer 56

The depth at which silica dissolution equals its accumulation, controlling the distribution of siliceous sediments on the ocean floor.

Question 57

Red Clay

Answer 57

A fine-grained deep-sea sediment primarily composed of wind-blown dust, volcanic ash, and small amounts of biogenic material, accumulating in areas with low biological productivity.

Question 58

Authigenic Sediments

Answer 58

Sediments that form in place through chemical reactions within seawater or sediments, such as manganese nodules and phosphorites.

Question 59

Evaporites

Answer 59

Minerals that precipitate from seawater due to evaporation, including salts like gypsum and halite, typically found in shallow, enclosed marine environments.

Question 60

Manganese Nodules

Answer 60

Rounded deposits of manganese, iron, and other metals that form slowly on the deep-sea floor through chemical precipitation from seawater.

Question 61

Rare Earth Elements (REEs)

Answer 61

A group of valuable metallic elements (like neodymium and yttrium) that accumulate in deep-sea sediments, often found in association with manganese nodules.

Question 62

Phosphate Nodules

Answer 62

Rock-like deposits of calcium phosphate that form on the ocean floor, often in areas of high biological productivity where organic matter decomposes and releases phosphorus.

Question 63

What are the various types of ocean sediments?

Answer 63

Lithogenic, biogenic, hydrogenic, cosmogenic

Question 64

How are lithogenic sediments derived, distributed, and found near?

Answer 64

Derived from rocks, transported by rivers, wind, ice, or volcanic activity. Found near continental margins and deep-sea basins.

Question 65

How are biogenic sediments derived, distributed, and found near?

Answer 65

Composed of organic material from marine organisms (e.g., calcareous & siliceous oozes). Found in areas of high biological productivity.

Question 66

How are hydrogenic sediments derived, distributed, and found near?

Answer 66

Formed by precipitation of minerals from seawater (e.g., evaporites, manganese nodules). Found in isolated basins or deep-sea environments.

Question 67

How are cosmogenic sediments derived, distributed, and found near?

Answer 67

Dust and debris from space, widely dispersed in small quantities.

Question 68

How does particle size effect the Relationship of Erosion, Transportation & Deposition?

Answer 68

Larger particles require stronger forces to be transported and settle quickly.

Question 69

How does turbulence effect the Relationship of Erosion, Transportation & Deposition?

Answer 69

Stronger currents suspend and move finer particles further.

Question 70

How does settling velocity effect the Relationship of Erosion, Transportation & Deposition?

Answer 70

Larger and denser particles settle faster, while smaller ones remain suspended longer.

Question 72

types of laminar flow and their differences

Answer 72

Laminar Flow – Smooth, parallel flow with minimal mixing; occurs in slow-moving water. Turbulent Flow – Chaotic, irregular motion that keeps fine sediments in suspension. Eddies – Circular currents caused by turbulence, affecting sediment transport.

Question 73

what Factors Controlling Fluid Density?

Answer 73

temperature, salinity, pressure

Question 74

How does temperature, salinity, and pressure affect fluid density?

Answer 74

Temperature – Cold water is denser than warm water. Salinity – Higher salinity increases density. Pressure – Greater depth increases density due to compression

Question 75

What Factors control Settling Velocity?

Answer 75

particle size, density, shape, water viscosity

Question 76

How does particle size, density, shape, and water viscosity control settling velocity?

Answer 76

Particle Size – Larger particles settle faster. Density – Heavier particles sink more quickly. Shape – Spherical particles settle faster than irregularly shaped ones. Water Viscosity – Warmer water reduces settling velocity

Question 77

What Ways in Which Water Transports Sediments?

Answer 77

Solution – Dissolved minerals transported in water. Suspension – Fine particles carried without settling. Saltation – Medium-sized particles bounce along the seafloor. Traction – Large particles roll or drag along the bottom.

Question 78

How is Clay removed from the Marine Environment?

Answer 78

Removed by flocculation (clumping of particles) or settling in low-energy environments.

Question 79

in what Ways Lithogenic Sediment is Transported into the Ocean

Answer 79

Rivers – Major source of terrigenous sediment. Wind – Carries fine dust and volcanic ash. Ice Rafting – Glaciers transport and drop sediments as they melt. Gravity Flows – Turbidity currents carry sediment downslope.

Question 80

Controls on the Distribution of Oozes in the Ocean Basin

Answer 80

Productivity – More biological activity = more biogenic sediment. Dissolution Rates – Oozes accumulate where dissolution is minimal. Depth – Below the CCD, calcareous oozes dissolve.

Question 81

Why Size Matters in Sediment Deposition & Erosion

Answer 81

Larger particles require stronger forces for movement and settle quickly. Smaller particles stay suspended longer and are easily eroded.

Question 82

Carbonate Compensation Depths & Stability of Aragonite vs. Calcite

Answer 82

Aragonite dissolves at shallower depths (ACD) because it is less stable than calcite. Calcite dissolves at deeper depths (CCD), around 4,500 meters. CO₂ levels and acidity increase with depth, causing dissolution.

Question 83

Factors Controlling the Depth of the CCD

Answer 83

Water Chemistry – Higher CO₂ and acidity at depth dissolve carbonates. Temperature & Pressure – Cold, deep water promotes dissolution. Supply of Carbonate Material – More carbonate input raises the CCD.

Question 84

Distribution of Sediment Types in Terms of Abundance

Answer 84

Near Coasts – Lithogenic sediments dominate. Deep Ocean – Biogenic sediments (oozes) and red clay are most common. Hydrothermal & Hydrogenic Areas – Authigenic sediments like manganese nodules.

Question 85

Formation of Red Clay Deposits

Answer 85

Found in low biological productivity areas below the CCD. Consists of wind-blown dust, volcanic ash, and cosmic debris. Settles slowly in the deep ocean basins.

Question 86

Layering of Deep-Ocean Sediments in the Atlantic & Pacific Oceans

Answer 86

Pacific Ocean – Deeper, colder, and more acidic → more red clay and siliceous oozes. Atlantic Ocean – Shallower, less acidic → more calcareous oozes. Layering is controlled by ocean depth, productivity, and dissolution rates.

Question 87

Most Common Sediments in Different Parts of the Ocean

Answer 87

Continental Shelf – Lithogenic sediments from rivers. Mid-Ocean Ridges – Biogenic oozes (calcareous & siliceous). Abyssal Plains – Red clay and hydrogenic deposits. Upwelling Zones – Siliceous oozes from high productivity.

Question 88

Formation of Hydrogenic Deposits

Answer 88

Evaporites – Form when seawater evaporates, leaving behind salts (e.g., halite, gypsum). Manganese Nodules – Form over millions of years by slow precipitation of metals. Phosphate Deposits – Accumulate where organic material decomposes, releasing phosphorus.