Science Erosion and Deposition - FINALS

speed of river is always fastest on ____ _____ because…?

outer curve - has to cover more distance by moving faster

In the experiment we did at school, why did the sand settle to the center of the beaker?

the sand went to where the water moved slower/where there was less power

What type of sediment sinks fastest?

large, round, more dense

Do flat or round sediment sink faster? Why?

round because flat has a lot more surface area - more resistance from water

Relationship between:
settling rate and particle size

settling rate and particle shape

settling rate and particle density

size- bigger settles faster - positive slope
shape - flatter settles slower - negative slope
density - denser settles faster (more surface area) - positive slope

In a container if tiny rocks and big rocks were dopped at the same time, what wouldl the setup be in the container?

big at bottom, small at top

Draw a diagram that shows what pattern various sized particles settle in a stream when it reaches a large body of water, slows, and deposits sediment?

draw

What side of surves in a stream erode most, outside or inside?

outside

does more sand deposit on the inside or outside edge of curves?

inside

what could you do to keep water from eroding soil in a stream?

add vegetation, rocks along side

How can you make a waterfall in a stream?

change elevation (dig or make higher)

how is a waterfall created in nature?

a river meets a hard rock and slowly erodes. the river goes over the rock and over softer rock downstream. when the soft rock is removed, waterfall forms

meander

curve in a river or stream

delta

triangular area of deposited sediment where river meets a larger body of water

oxbow lake

meander that gets cut off from a stream

floodplain

low lying ground near a river that’s prone to flooding

runoff, what factors affect runoff?

water that moves over earth’s surface
amount of rain, vegetation, soil type, shape of land, how people use the land

rills and gullies

rills are tiny cracks in soil, gullies are wider cracks in earth

when surface water runs off it flows from ___ to ____ to ______

river, gullies, streams

diff between streams vs rills+gullies

streams always have water, but rills and gullies do not have to have water

alluvial fans

fan shape, wide sloping deposit where stream leaves a mountain range/higher elevation, goes downhill, doesn’t always have water

deltas

triangle/arc shape (can be many shapes)
sediment settled into another body of water builds up, flows straight, not downhill, usually has water

why can rivers as a political boundary be problematic

rivers will change shape over time - gives one place more land than another

should houses be built near floodplains and why?

No bc floodplains are more subject to flooding and houses near them could get flooded. also taxed will get higher (so govt has enough $ to repair damage)

how are waves created?

WIND AND TECTONIC PLATE MOTIONS! (earthquakes, wind) (Transfer of KINETIC ENERGY to water molecules!)

what happens to sand when it is hit by waves/how does it move?

spreads out - each particle gets carried and sand gets mixed into water

What affects beach erosion

wind, tectonic plates, people’s actions, salinity levels, tide, etc

Name the two processes of erosion by waves and describe them

Impact - physical collision of water with surface that carries particles away
abrasion - sediment scratching against shore and more sediment carried by larger waves

4 landform types created ny wave erosion

sea stack, sea cave, wave cut cliff, sea arch

sea arch

natural opening eroded out of cliff by wave action - can even be a previous sea cave that completely eroded

sea cave

cave formed in cliff by wave action - erodes soft rock first

sea stack

steep vertical column created by a collapse of sea arch due to wave action

wave cut cliff

narrow flat area at base of cliff along coast, caused by wave action

three types of deposition by waves

beach, barrier beach, spit

beach

area of sediment along a coast, sediment dropped off as waves slow down

barrier beach and examples of developed ones

long narrow island formed parallel to shore
provides critical protection of mainland

miami beach FL, long beach island NJ, outer banks NC

spit

beach that projects like a finger
caused by longshore drift

longshore drift

sediment carried at an angle due to wind

draw a picture of longshore drift

done