Earth Science Chapter 10

Front 1

where does most final deposition occur and why?

Back 1

in large water bodies bc running water is the ost important erosional system

Front 2

when does deposition occur?

Back 2

when the velocity of the stream,, wind, or other erosional system decreases or just stops moving

Front 3

what two factors affect the rate of deposition?

Back 3

the velocity of the erosional system and the characteristics of the sediments themselves

Front 4

rate of stream in relation to size of particles it can carry

Back 4

the faster a stream, the larger size particles it can carry

Front 5

what happens when the speed of a stream drops below the speed it needs to carry certain sediments

Back 5

the sediments are deposited

Front 6

what aspects of sediments affect how fast they will be deposited in air or water environments

Back 6

size, shape, density, and sautration of dissolved minerals

Front 7

rate--size

Back 7

larger sdiments settle out first

Front 8

wh?

Back 8

because they are heavier and sink faster

Front 9

rate---shape

Back 9

the more rounded a sediment, the faster it will settle out
the more flattnened it is the greater its resistance to deposition

Front 10

rate-----density

Back 10

the higher the density, the faster it will settle out in air or water

Front 11

affect of saturation of dissolved minerals

Back 11

if evaporation, temp hanges, or increaes in amount of dissolved miinterals in a water body result in a saturated condition, the dissolved mineral or minerals will settle or precipitate out of the dissolved dontion and crystallize. as a result, rocks composed of one mineral can form

Front 12

graded bedding

Back 12

a sediment later formed when a mixture of seidment sizes in water settles out rapidy and a horizonal bed develops w/ sediment size decreasing from bottom to top

Front 13

sediment-laden density currents

Back 13

associated w/ graded bedding
most common of the sloped ocean bottoms off the coasts of continents and on a lake where flooding streams rapdily decrease inv elocity when they enter

Front 14

which particles settle out first when the velocity of a wind or water erosional system gradually decreases?

Back 14

the larger, denser, and more rounded rediments

Front 15

what does this result in?

Back 15

layers w/ horizonal sorting, in which sediemnt size, roundness, and density generally decrease in the direction toward which the erosional system was moving

Front 16

explain horizontal sorting where a stream enters the ocean or lake forming a delta

Back 16

the large sediments settle first (nearer the shore). sediments become smaller as distance from the shore increases.

Front 17

what happens to the sediments when there is mass movement, such as a rock fall, landslide, or avalanche

Back 17

the sediments are usually dumped together in a random deposit that is unsorted and unlayered, similar to glacial deposits

Front 18

where does the stream have max. potential energy

Back 18

at the source, or beginning, of the stream

Front 19

what happens to the energy as the stream flows toward its mouth, or end?

Back 19

potential energy is continuously being transformed into kintetic energy

Front 20

where does the stream have its greatest velocity and greatest kinetic energy?

Back 20

where the slope of the stream is steep

Front 21

where is erosion dominant?

Back 21

wherever the kinetic energy of the system is large?

Front 22

where is deposition dominant?

Back 22

where the kinetic energy is small

Front 23

what regions does erosion occur in?

Back 23

in regions of sleep slope or high discharge

Front 24

what regions does deposition occur in?

Back 24

regions of gentle slope or low dischage

Front 25

where is deposition particularly rapid?

Back 25

at the mouth of the stream, where the kinetic energy becomes zero

Front 26

what would happen if one or more tributaries were to enter a stream?

Back 26

it would increase the mass or discharge of water, thus increasing the potential energy of the stream. the velocity would increase, causing eriosion to increase and deposition to decrease

Front 27

where do the interfaces between erosion and deposition exist?

Back 27

at the meanders in the model stream
between the source and the mouth of a stream
may also be found where changes in slope occur

Front 28

dynamic equilibrium

Back 28

rate of erosion equals the rate of deposition by the stream as a whole

Front 29

depositional agents

Back 29

streams, glaciers, water waves and currents, wind, and mass movements

Front 30

where does a stream deposit sediments?

Back 30

sediments are deposited on the inside of the meanders where stream velocity is slow

Front 31

levee

Back 31

a mound of sediments formed at the edge of a river when a stream floods and overflows its banks

Front 32

where does most of teh sediemnt go when a stream floods and overflows its bnks?

Back 32

it is spread over a relatively flat regions to the ssides of the stream forming a flood plain

Front 33

delta

Back 33

deposition at the end of a stream with characteristic horizontal sorting

Front 34

why might a delta not form is there are strong ocean or lake currents

Back 34

bc the velocity of the water is not reduced enough at this location

Front 35

moraine

Back 35

unsorted piles where the sediments a glacier is carrying is dropped. it is at the end of a glacier where htere is a balance between melting and forward movement

Front 36

ground moraine

Back 36

a moraine that is a thin sheet deposited from the bottom of the glacier

Front 37

what is moraine from?

Back 37

direct glacier deposits

Front 38

what do ground moraines cover?

Back 38

much of northern US including much of NY state

Front 39

terminal moraine

Back 39

formed when a if the end of a glacier stays in one location for some time and the glacier builds up a pile of sediments

Front 40

drumlin

Back 40

a feature similar to the shape of the end of an inverted spoon-formed if a flacier mounds up the grand moraine into a streamlined over shape

Front 41

what does the drumlin indicate

Back 41

the direction a claier came from by being oriented with direction of former glacier movement

Front 42

how can u tell?

Back 42

drumlines have steeper slopes pointing ot the direction the glaciers came from

Front 43

kettle lakes

Back 43

sometimes as a glacier melts back, it leaves block of ice in the terminal or grond moraine. when these blocks of ice melt, they leave behind circular depressions called kettle holes or kettles. if theese kettles intersect the water tables, they will become filled with water and then are claled kettle lakes

Front 44

outwash plain

Back 44

whenerver glaciers melt, running water will carry sediments from the glaciers to produce layered and sorted sediment deposits when the water slows down or stops. one such feature is an outwash plain-- a broad delta-like feature

Front 45

beach

Back 45

a strip of sediment at teh coastline built up by wave movement towards the shore

Front 46

what do varrier island often do for the shore?

Back 46

protects it from pounding by storm waves

Front 47

sandbars

Back 47

depositional feature formed by longshore currents transported sediment-sand, and when the velocity of water slows, deposition creates a sandbar

Front 48

barrier island

Back 48

if a sandbar rises about average sea level, winds will help to pile up the sediments. thne vegetation can stabilize this offshore seidment pile, creating a barrier island.

Front 49

where are barrier islands common

Back 49

along the east and southeast coast of the US

Front 50

dust

Back 50

sediments smaller than sand (silt and clay)

Front 51

what does wind usually tranpport and deposit?

Back 51

only sand and smaller sized sediments

Front 52

sand dunes

Back 52

sand is deposited by wind if layers or in mounds called snad dunes

Front 53

slope of sand dunes

Back 53

have a gentle slop facing into the wind, and a steeper slope oin the side the wind is blowing towards

Front 54

which way do sand dunes migrate?

Back 54

in a body downwind--in the direction the wind is blowing to---creating layers of sloping sorted sediment.

Front 55

what is the sand within the sand dunes like and why?

Back 55

usually very rounded and frosted in appearance due to numerous collisions of sand grains during erosion

Front 56

what are depositional features like when desidemts are deposited by mass movement like an avalance?

Back 56

unsorted and unlayered sediemnts

Front 57

what will the sediments look like?

Back 57

not very rounded-sharp sides

Front 58

what is the most recognizable depositional feature of mass movement ?

Back 58

a pile of sediments that is the result of sediments often found at the base of cliffs

Front 59

where does outwash plain come from

Back 59

deposited mostly by water from melting glaciers

Front 60

where down moraine come from

Back 60

deposited by glaciers

Front 61

where does drumlin come from

Back 61

glaciers

Front 62

where does barrier island come from

Back 62

waves and shore currents

Front 63

where does sand dune come from

Back 63

wind

Front 64

where does flood plain come from

Back 64

streams