weathering, erosion, deposition

where does deposition mainly occur by?

streams, glaciers, waves/currents, wind, mass movements

glacial erosion features/evidence

sub-rounded and scratched, u-shaped valleys, glacial erratics- boulders, unsorted sediment

alluvial fan

stream deposition on land

what occurs when a rock is crushed into a oil of fragments? total surface area ___________ and chemical composition ___________

increases, remains the same

the formation of soil is primarily the result of

weathering and biological activity

types of chemical weathering

1. oxidation 2. hydration 3. carbonation

types of weathering

1. physical/mechanical 2. chemical

most common places for wind erosion

- arid regions, like deserts - lake or ocean coastlines

glacier surrounding terminology

- moraines (ground and terminal) - drumlins - kettle lakes - outwash plains

types of physical weathering

1. root action 2. frost action/wedging 3. exfoliation 4. abrasion 5. wave action

energy transformation in an erosional-depositional system

-high kinetic energy = erosion -low kinetic energy = deposition -dynamic equilibrium: rate of erosion = rate of deposition

weathering occurs when rocks are exposed to...

1. air (atmosphere) 2. water (hydrosphere) 3. living things 4. pressure changes

factors affecting the rate and type of weathering

1. exposure 2. particle size 3. mineral composition 4. climate

evidence of erosion

1. if sediment has been moved from its source 2. transported material have distinct properties that indicate the agent of erosion 3. streams: the sediment is rounded and smooth (the longer the sediment is eroded -> smoother and rounder)

velocity of streams rules

1. if sediment is to be transported by water, the water has to be moving 2. as velocity of a stream increases, the AMOUNT of sediment transport increases (direct) 3. as a velocity of a stream increases, the SIZE of transported particles increases (direct)

what affects the rate of deposition?

1. size: larger particles are heavier and settle faster than small particles; particle size increases, settling time decreases 2. shape: rounder sediments settle faster than flat particles bc less surface area against friction 3. density: high density particles settle faster

what determines stream velocity?

1. slope/gradient (as slope increases, velocity increases) 2. discharge (volume of water increases, velocity increases) 3. position in stream (top = fastest, bottom = slowest)

ways that stream carry sediment

1. solution 2. suspension 3. rolling and bouncing

distinct properties of transported material

1. wind: rounded and pitted 2. glacier: sub-rounded and scratched 3. gravity: sharp and angular

a sedimentary deposit produced by wind erosion is most likely composed of 1. shells of varying size, shape, and composition in isolated mounds 2. a range in particle sizes from 1.0 to 10.0 cm in diameter in thick layers 3. sorted fine-grained particles in cross-bedded layers 4. flat, angular boulders in unsorted piles

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**STREAM LANDSCAPE FEATURES DIAGRAM

PAGE 56, 57, 58, 59

natural levees

a deposit of sand on either side of a river

oxbow lake

a meander that has been cut off from the river

soil

a mixture of rock particles and decayed organic material on earth's surface that supports rooted plants; over time soil develops horizontal layers with a distinctive profile

sand dune

a pile of wind-blown sand created by wind; layers or mounds that sand is deposited in; have a gentle slope facing into the wind and a steeper slope on the side that the wind is; cross bedded sandstone

tributary

a smaller stream that flows into a larger stream

barrier island

a thin strip of land created by deposition

which type of climate has the greatest amount of rock weathering caused by frost action?

a wet climate in which temperatures alternate between below freezing to above freezing

man-made erosion

activities including deforestation, overgrazing, construction, poor farming increase exposure to agents of erosion

water waves and current examples

beaches, barrier islands, long shore current

kettle lake

block of ice left by after a glacier melts and fills with water

chemical weathering

breakdown of rock by chemical action that results in a change in mineral or chemical composition

glaciers

carries sediment by scraping and dragging it along the surface (glacial grooves)

exfoliation

changes in temperature cause the rock to expand, contract, and eventually break

which types of weathering and erosion are primarily responsible for the formation of caves?

chemical weathering and groundwater flow

climate

chemical weathering increases in warm, humid climates; physical weathering increases in cold, humid climates; dry/arid very little weathering

when wind and running water gradually decrease in velocity, the transported sediments are...

deposited over a period of time, and are sorted by size and density

mineral composition

different minerals have different resistance to weathering, hard = more difficult to weather, soft = easier to weather

solution

dissolved minerals are transported this way

running water

dominant moves over land and picks up and carries weathered rock material (watershed, tributaries) evidence: rounded, smoothed, polished, v-shaped valleys

when winds slows down or stops, the sediment it carries is ___________

dropped/deposited (only sand and smaller sized sediment)

which is the direction of wave movement in the barrier islands?

east to west

oxbow lakes are generally formed by

erosion along the outside banks of a curve in a meandering stream

long shore current

flow of water that can carry sediments parallel to the shore

unsorted, angular, rough-surfaced cobbles and boulders are found at the base of a cliff. what most likely transported these cobbles and boulders?

gravity

what is the top layer of soil?

humus; consists of weathered rock particles and organic material from plants and animals

which agent of erosion transported the sediments that formed moraines?

ice

what are sediments moved by?

ice, gravity, water, or air

floodplain

land where excess water from river goes to

rolling and bouncing

large solid sediments (sand, pebbles, boulders) are carried this way

wind erosion

loose sediment the size of sand or smaller are moved by wind (most common arid, sand dunes- wind comes from the gentle slope) evidence: rounded and pitted

hydration

minerals in rocks are dissolved by water which creates a new mineral compound

exposure

more exposure/closer to the surface, faster weathering

horizontal sorting

occurs when larger, denser, and more rounded settle out first and the velocity gradually decreases -occurs at a delta: where a stream or river flows into the ocean

mass movement landscape

piles of unsorted, unlayered sediments that have sharped edges

outwash plain

plain formed of glacial sediments deposited by meltwater outwash at the bottom of a glacier

gravity/mass movement

sediment moving down slope due to gravity (ex. rockslide, mudslide, landslide) evidence: sediments that are sharp and angular

during deposition, sediments of similar size, shape, or density get ____________ by type

separated/sorted

root action

plants roots grow through cracks and break the rock

types of soil

residual and transported

carbonation

rocks, especially limestone react with carbonic acid (caves & stalactities)

which agent of erosion creates sorted sediments?

running water

examples of mass movement deposit sediment of all different sizes, shapes, and densities at the _________... resulting in __________

same time, unsorted deposition

what happens when a shoreline has a projection out into the ocean (jetty)?

sand is deposited on the side facing the oncoming longshore current (the water slows down and the sand settles out) the side facing away gets eroded

stream: deposition/erosion

slow=deposition, fast=erosion

suspension

small particles (silt, clay) are lifted up

particle size

smaller particle size, greater surface area and the faster the weathering

transported soil

soil that has been moved from one place to another area (common in NY)

residual soil

soil that has formed from the bedrock beneath it

watershed

the area of land drained by any one stream (drainage area)

physical weathering

the breakdown of rock into smaller pieces without chemical change

weathering

the breakdown of rocks at or near Earth's surface into smaller particles called sediment

when a stream is straight, where is the velocity the fastest?

the center

erosion

the process by which sediments are picked-up and transported

deposition

the releasing or depositing of solid sediment and dissolved minerals

when a stream curves, where is the fastest water?

toward the outside of the curve

valleys eroded by glaciers are __ shaped, valleys eroded by streams are __ shaped

u, v

glacial moraine

unsorted piles of sediment formed at the end and edges of a glaciers (ground and terminal)

jetties and groins are...

used to prevent longshore drift

valleys eroded by streams

v-shaped

sediment is deposited as a river enters the lake because the

velocity of the river decreases

when does deposition usually occur?

velocity or speed of the stream or wind decreases or stops

frost action/wedging

water freezes and expands which causes the rock to break

wave action

waves pounding against rocks - sand and rocks in the waves help to break up the shoreline.

difference between weathering, erosion, and deposition

weathering: the action of breaking down the rock erosion: the transport/movement of the particles deposition: where the particles are placed

drumlin

whale backed hills (oval shaped) of unsorted sediment; glacier game from the direction of steep slope, dropped sediment which created a gradual slope

definition and examples of agents of erosion

what transports the sediment 1. gravity/mass movement 2. wind 3. ice (glacier) 4. ocean waves 5. humans 6. water**

saturation of dissolved minerals

when a body of water becomes 100% filled with dissolved minerals, the water evaporates and minerals settle out

oxidation

when elements (iron) in the rock react with oxygen to create rust

how is a beach created?

when ocean waves slow down as they approach the shore, they move sediments towards the shore

abrasion

when rocks or sediments grind against another rock - stream abrasion: the rounding and smoothing of rocks as they tumble in a stream - wind abrasion: dry climates, the wind picks up sand and blows it against rocks causing 'pitting' (sandblasted appearance)

vertical (gradual) bedding

when sediments settle out quickly -layers develop with sediment size increasing from top to bottom -oceans/lake bottoms

ocean waves

where ocean meets land, waves acts as agents of erosion (evidence: sharp cliffs)

sand dunes are formed by ________ and sand bars are formed by ___________

wind waves

natural sandblasting (abrasion) of surface bedrock in the desert region is the result of

wind erosion