TEST #2 Flashcards

Question

Where us most water stored?

Answer 1

Oceans + Glacial Ice ***The rest of the reservoirs hold a very small percent

Answer 2

Hold very small amounts of water -- water in category primary is found in streams - Water in reservoir comes from precipitation falling into the lakes and streams

Answer 3

Clouds + the things that fall like rain ***0.001% of total water budget

Answer 4

NOT considered groundwater because the soils are not saturated BUT they still have moisture -- the moisture is not filling the pore space

Answer 5

Small amounts of water are present in living organisms

Answer 6

A given water molecule may move quickly through some reservoirs or it may be stored for thousands/millions of years - A given water molecule will go through the reservoir BUT it may spend more time in one reservoir than another Quickly = atmosphere Stored = Deep groundwater Example - A water molecule spends less time in the atmosphere as water vapor than the amount of time it would spend in the ocean or in groundwater

Answer 7

Deep groundwater --> some of the water being pumped out to drive agriculture is water that has been in aquifer for millions of years

Answer 8

The hydrologic cycle is tied to the geosphere + biosphere --> it is tied to erosion + sedimentary rock formation Geosphere --> tied by erosion + sedimentary rock formation Biosphere --> water is required for life Example -- Sedimentary rocks + erosion

Answer 9

Sedimentary rocks --> usually involve some form of transport in water -- sediments might be physically broken apart and carried in a stream and then deposited and then get cemented together OR the water can dissolve minerals (like halite) --> THEN when the water gets saturated or the water evaporates and you get a mineral deposit Erosion --> Water is the main thing used for erosion ***Shows that the geosphere and the hydrologic cycle are related

Answer 10

Any body of water confined within a Chanel of any size - Has a geologic area that it is contained in that is defined by topography

Answer 11

Streams flow downhill and ultimately go into the ocean -- they move in response to gravity

Answer 12

Streams come in all different sizes - can be a giant river or a small creek that occurs because of a big wave

Answer 13

Has a geographic area that it is containing in the is defined by topography ***There are divides between the drainage basin for the stream network

Answer 14

Topographic area

Answer 15

The region from which a stream draws water

Answer 16

The size of the stream is a function of the area of the drainage basin upstream -- the area of the drainage basin upstream determines how much water from precipitation is flowing into the stream ALSO affected by: 1. Climate 2. Vegetation 3. Underlying geology

Answer 17

Stream ordering affects the size of the stream --> Looks to see how many chanels come together ***More upland in darinage basin = 1st order --> When the first two chanels come together = get second order --> Multiple second order come together to form third order --> If third order come together then you get fourth order

Answer 18

Looks at how many chanel come together -- affects stream size ***More upland in darinage basin = 1st order --> When the first two chanels come together = get second order --> Multiple second order come together to form third order --> If third order come together then you get fourth order

Answer 19

Size of streams change over years due to climate + rainfall events

Answer 20

Stream 1 in stream ordering

Answer 21

You could say that the Missouri river is just part of the Mississippi river because they join together ***The same applied to the Ohio river - Ohio + Missouri both join the Mississippi --> all water in the whole area eventually drain into the Mississippi River

Answer 22

Mississippi river

Answer 23

Main Drainage basin in U.S. - One the sides of Mississippi = have Rocky mountains + Appalachians --> Have topgenic high spots on both sides of the Mississippi Drainage basin

Answer 24

Two topographic high spots Rocky mountains = West Appalachians = East

Answer 25

Things west of Appalachians = go west Things east of Appalachians = go east

Answer 26

Streams go towards the east coast - NE = have smaller drainage basins that DO NOT go to the Mississippi

Answer 27

Flow south --> Binghamton is the most upland part of the Chesapeake bay drainage basin ***They flow into chesapeake bay darinage basin

Answer 28

Binghamton

Answer 29

Get to the Catskills --> things east of Binghamton = doesn't go over the Catskills = goes towards NYC = goes to the NY watershed ***Catskills = act as a barrier

Answer 30

The volume of Water flowing through past a given point (through a given cross section) in a specific length of time - Calculating how much water is moving through a Chanel at a given time ***RATE MEASURMENT Discharge = Cross sectional Area X Stream velocity

Answer 31

Discharge = Cross sectional Area X Stream velocity - Look at how wide the stream is + Look at how deep it is as you walk across -- take measurements at certain intervals --> get depth measurements from one bank to another --> take average - Use average to estimate the cross sectional area of the water THEN -- look at flow

Answer 32

- Look at how wide the stream is + Look at how deep it is as you walk across -- take measurements at certain intervals --> get depth measurements from one bank to another --> take average - Use average to estimate the cross sectional area of the water

Answer 33

Look at the flow

Answer 34

Use instruments that you can put in the water - The instruments have a propeller --> the faster it spins then the faster the water is moving ***Less specific way = can just see how long it takes something to go from one point in the stream to another point in the stream

Answer 35

Can take measurements at intervals because water might not be moving at the same rate in the center as it might be moving in more shallow areas ***If you don't care about being precise then can just take one measurement

Answer 36

Headland = more upstream + higher topographic areas

Answer 37

Streams go from higher topographic areas to lower topographic areas eventually draining to the ocean at sea level

Answer 38

Flow faster ***Closer to the stream source = the faster the stream moves

Answer 39

Stream Chanel morphology = function of the gradients (steep vs. flat) and the sediment supply (amount of sediment that the stream is carrying 1. How much slope is the that the stream is flowing over 2. How much sediment is the stream carrying (does it have a heavy load of sediment that is moving OR is it farther from the source of sediment so most sediments have settled already)

Answer 40

Usually are closer to the source + have higher flow rates --> can transport more and larger sediments - Usually the tream is closer to topographic highrise (hills + mountains) ***higher gradient areas have more + larger sediments

Answer 41

Hills/mountains -- because those places are being eroded down ***Erosion = trying to make it all level

Answer 42

Trying to level out the topographic high spots ***Erosion = trying to erode the high places down to create a gradient equal to surrounding areas - Essentially gravity at work using water as a tool

Answer 43

Closer to the source -- have larger sediments (cobbles + Boulder) --> as gradient levels the energy is less = the heaviest sediments settle first --> only the smaller ones are left

Answer 44

Large = Boulders + cobbles Small = Sand + silt

Answer 45

The heavy sediments settle first --> then only have the small ones in low gradient areas

Answer 46

Only have the smaller sediments left (sand + silt)

Answer 47

Higher = the water is moving faster

Answer 48

Higher = the water is moving faster = the sediments are bigger -- Cobbles + Boulders (have more energy to carry heavy sediments) Lower = the water is not moving as fast --> streams might be getting larger in size BUT they are not moving at fast

Answer 49

The size gets bigger BUT the rate is slower (they are not moving as fast) ***The get larger in size because streams might have more channels feeding into them creating a bigger stream in the low lands

Answer 50

1. Mineral deposits --> One way that we find economic deposits to mine = places with sedimentary deposits that are deposited by streams 2. Flooding events --> Way environment affects humans

Answer 51

1. Braided Streams 2. Meandering Streams

Answer 52

Closer to the sediment source + closer to topographical high spots

Answer 53

Streams coming right out of the mountains -- closer to the headland areas of water shed ***Coming from a high area that is just starting to level off

Answer 54

The heavy sediments are getting deposited = they accumulate = water goes around the sediments = creates braided affect - Water finds channels and is weaving through the sediments that is coming from surrounding highlands ***Because there is so much sediments it causes the stream to have many channels to flow around the sediments = makes the braids

Answer 55

HIGH sediment load -- water is just just trying to find a path through the sediments - Sediments form island in Chanel - Sediments = course grain (Ex. Gravel) ***Because there is so much sediments it causes the stream to have many channels to flow around the sediments = makes the braids

Answer 56

Close to the headlands --> makes it high velocity ***Usually forms just downstream of a decrease in gradient where water begins to slow down and drop their larger sediments ***Places were the water is coming out of really steep gradients

Answer 57

Also form on the front side of receding (melting) glaciers BECAUSE there was a lot of sediments that were being carried or pushed by the glaciers being washed out ***Because glaciers have a lot of sediments - As glaciers melt = provide s a lot of water --> water has the sediments that were in ice = forms braided streams

Answer 58

Typically low gradients stream further from sediment source

Answer 59

Low gradient --> Further from sediment source - Flatter topography + further from highspot ***Kinds of rivers that they have in the midwest + places that are lower gradient

Answer 60

Streams in the midwest -- low gradient

Answer 61

Water = not going as fast

Answer 62

Not carrying a lot of sediments

Answer 63

Water flows in a way of the path of least resistnce = causes it to bend/meander -- not going in straight line

Answer 64

As it goes around the bend = amplifies the curve --> flows faster on the outside of the bend ***Water flows faster on the outside of the bend --> centripetal force pushes the water to the outside of the bend = over time one side gets exaggerated --> bend becomes ore pronounced over time AND eventually the stream can cut through and abandon the bend

Answer 65

Water flows faster on the outside of the bend --> centripetal force pushes the water to the outside of the bend = over time one side gets exaggerated --> bend becomes ore pronounced over time AND eventually the stream can cut through and abandon the bend

Answer 66

Low gradient streams in flat topography = don't travel in straight lines --> small irregularities in the channel become amplified by erosion to form bends + meanders

Answer 67

Called meandering because when the water is in a low gradient system it doesn't travel in a straight line --> flows and looks for the past of least resisten = it winds around --> when it makes it way around the bend = it moves faster on the outside than the inside because of centripital force --> when water is moving faster its more erosive than when its moving slower --> Over time the outside where it was moving faster has more erosion and the slower drops more sediement grains RESULT: Overtime on the outside of the bend where water is moving faster you have more erosion happening AND on the inside where water is moving slower you have more sand being deposited --> overtime the meander moves as a unit -- outter bank is being eroded + moving and the inner part deposits and moved = EXAGERATES THE MEANDER MORE - Eventually the meaders = become very exagertaes = now water will break through becvause it wants to go in the path of least resistence = it staightns out and the process starts again

Answer 68

Exaggerates meanders If look over time – will see meander will move as a unit → outer band is being eroded and moving and inner part deposits and also moves = exaggerates the meander over time It moves around like a snake

Answer 69

Eventually the meander is TOO exagerated --> evnetually water will break through because it wants to go the path of least resistence = it straightns out and the process starts again - Can get abondded meanders in a meandering stream

Answer 70

Lakes that are abandoned meanders -- still collect want BUT not part of stream anymore ***Abandoned meander

Answer 71

Outside edge of the meander ***More steep -- when have erosion = have steeper gradients = can be very steep Cut bank:Erosional bank on the outside edge of a meander where water is travelling fastest around the bend.

Answer 72

Inner part of meander --> less steep ***Area where there is less deposition happening Point Bar: Sediments deposited on the inside of a meander where water is travelling slower around the bend

Answer 73

In point bar -- pleaces where we might look for minaerlas + metals in stream system --> pleaces where the stream is going around a bend -- makes sediemnt deposits

Answer 74

Look for ancient point bars

Answer 75

Fin in North/Midwest --> AFTER you get passes mountains and you are in low gradient plane regions - Farther from mountains -- now just have water making its way down watershed BUT the gradient is not as steep = its not going as fast BUT might have more streams that feed into it = have total larger volume but might not be traveling as fast

Answer 76

Have higher volume BUT the speed is slower

Answer 77

Sediment = now finer grains (sand size or finer) --> Larger grain sediments = came out of suspension by the time it is downstream ***It might be moving through deposits of finer grain that were deposited before

Answer 78

Broad flat expanse on either side of channel created by erosion and deposition described above. This is the area that usually is submerged during normal flooding events.

Answer 79

Surrounding sediments might be an ancient point bar that were from pre-existing streams

Answer 80

partially because the river deposits were fertile --> because they have minerals in water + organic deposit --> when it floods it puts the good things into field = it is good to farm there

Answer 81

When streams flood = times where there is a big water event --> causes streams to leave its channel -- places where the water goes when stream water leaves its channel = the surrounding areas --> areas that meanders have curved out = called "floodplains"

Answer 82

The velocity of the water (the gradient of the stream) High velocity (steeper) --> carry gravel or boulders along with finer sediments Leveled out gradient (farther from the source) --> carries successively finer and finder grain sizes

Answer 83

As gradient levels out (moves away from teh source) --> successivley finer and finer grain sizes will drop out - In a slow stream only fines and dissolved minerlas will be trasnported ***As water moves slower as the gradient levels out the first thing to deposit out are the courser grain – as it moves to flat areas the stuff that it is carrying successive deposit out based on grain size (at the start is courser → then goes to finer that is carried farther) ***Gravel --> Sand --> Clay

Answer 84

Gravel --> Sand --> Clay

Answer 85

When a stream flows into a standing body of water like lake or ocean flow drops to zero and all remaining sediments are deposited

Answer 86

Larger --> because faster water can carry big things

Answer 87

Even though the streams are bigger in size they ahve less energy = can only carry smaller sediments ***Flat gradinets -- carry finer sediemnt size

Answer 88

Grains are too large to be freely carried along --> instead they are rolled or bounced along

Answer 89

Get Alluvial Fans ***Occurs when a stream suddenly loses force BUT is still close to topographical source

Answer 90

Fan or cone shaped seidments or deposit ***Result from a sudden decrease in stream velocity when a steam flows from hills onto a plain OR when a tributatry empties into a slower moving stream

Answer 91

The sediment or allivial tends to be poorley sorden -- because the sudden decarse in velocity causes a range of sediment sizes to be deposited

Answer 92

Alluvial fans are NOT the same as deltas because of loss of velocity when they enter the body of water --> alluvial fans are not entering water body they just have decrease in velocity

Answer 93

1. Death valley California 2. The Rocky Mountains in Colorado

Answer 94

***Example of alluvial fan formation Occasionallt gets stroms --> gets rain = causes the dry streams in valleys to flow --> when they flow they go fast because there is high gradient = it carries sediemnts --> when the stream flows and suddeneley levels out = drops all of teh sedemenits -- hits decreasing gradient and just hits the breaks = get alluvial fan - Sediements get dumped in an alluvial fan

Answer 95

They might have valuable mineral + might have gold -- might be a a place in the future where we look for gold + might be a place to mine

Answer 96

Tends to be poorly sorted -- IN meandering streams over the course of the movement the grains get dropped off (things at high elevation start to get dropped off earlier + things at low gradient are smaller sized) --> means that at the end it is more uniform in size because the courser grains have been dropped out VS. Alluvial fans all of the sized of rocks all suddenly lose velocity = pretty much everything is dumped in the one area

Answer 97

Triangular shaped bodies of sediment that build up where streams carrying a significant sediment load empty into a still standing water body - At the very end of the stream

Answer 98

At the very end of the stream -- can have it when the stream goes to the ocean or a lake

Answer 99

Mississippi Delta

Answer 100

- Primarliy made of fine grain -- sand + silt + mud - Courser grain that is in the delta = placves where the river chanel is currentley OR has been in the past - Outskirts of the river chanel + areas where the river chanels used to be = has stuff around it (fine grain -- silt + mud deposits)

Answer 101

Primarily fine grain (Sand + Silt + mud)

Answer 102

Where the chanel is flowing OR plaves wherte the river chanel has been in the past = has the most energy - Sand = usually the coursest = the coursest grain size is where the most energy is

Answer 103

Get there when the chanel floods -- when floods the water that goes to either side doesn't have a lot of velocity BUT still has some small sediemnts and clays in suspension --> When it floods they deposit silt and mud to either side

Answer 104

Flooding happens when you have too much water --> could have precipiation event either in immediate vecinity or upstream to cause the water level to exceed the level of the banks of the stream channel

Answer 105

Could occur in the immediate vicinity or upstream

Answer 106

When discharge exceeds the average maximum --> the water level can exceed the level of the banks and the stream will flood

Answer 107

When discharge exceeds the level of the banks of teh channel

Answer 108

May happen every couple of years

Answer 109

Less often

Answer 110

Most stream floods are linked to large precipitation events --> precipitation can be in the immediate vicinity OR can be further up in the watershed

Answer 111

Can still lead to floods --> If you have precipiation that occirs futher up in the watershed THEN that water will eventually make its way down into the larger broader streams -- depending on the severity of the precipiation events = it can flood

Answer 112

Affects how much the stream will flood -- affects severity of flood

Answer 113

When rain falls or snow melts -- some of the water goes into soil + can be stored as ground water -- goes to the water table --> THEREFORE porosity and permeability affect floods severity - Lower Porosity and Permeability --> water will just flow over land and will make its way to stream systems = more flooding

Answer 114

1. How much rain you get 2. Porosity + permeability 3. Topography 4. The amount of development in the area

Answer 115

If you have flooding at steeper gradient -- the water will run off faster = more inclines to start moving over surface ***Higher topography -- increases the rate of runoff and gives less time for water to infiltrate the ground

Answer 116

1. Building buildings and roads make the water shed less permeable + we put in sewers

Answer 117

Sewers put the water into the water shed immediately = increases flooding

Answer 118

Now instead of flowing in the channel --> the water will come out in every direction

Answer 119

Plants provide a physical barrier to runoff + increase soil permeability with roots + directly absorb water - They make areas less susceptible to flooding ***Arid areas = more susceptible to flooding

Answer 120

During a flood -- stream velocity + Discharge increase

Answer 121

The elevation of water surface at any point -Every stream is in equillibrium -- by nature it is designed to have wtaer at a certain stage above sea level BUT when you have a flood that causes elevation of water to increase above sea levle (when the stream is above the level of equillibrium) = HAVE FLOOD -- water escapes ***Measure elevation of water surface -- look to see how high it is above sea level

Answer 122

A stream is at flood stage when water exceeds bank height

Answer 123

When maximum stage is reached

Answer 124

Using Maximum Stage -- magnitude of floods are often described by maximum stage reached

Answer 125

Places downstream of a flood may not flood until sevral days after a flood begins --> MEANS flooding can continue after rain stops

Answer 126

1. Can affect small localized areas (upstream floods) 2. Can affects entire regions of a state or country (downstream floods) ***Affect depends on the size of the event and the streams involoved

Answer 127

1. The size of the event 2. The streams involved

Answer 128

Have a more immediate and localized affect

Answer 129

NOT immediate affect + might not be affected BUT it will be affected it it is a long or high rainfall - Can affect entire regions of stages or countries

Answer 130

1. Jonhstown PA 2. St.louis

Answer 131

Mountain in Appalachians --> historically get hit by a lot of floods because its in the headlands of the drainage basin + it is near a large creek - They have been affected by numerous events of upstream localized flooding during its history

Answer 132

Example of a downstream flood

Answer 133

1. How much rainfall was there? 2. How does the stream at any particular place respond to rainfall

Answer 134

If you have a rainfall event upstream in the highlands = that upstream part floods immediatley BUT that water will go down the watershed where the streams are able to hold more water THERFORE you might have a flood that occurs upstream that only affects one area (have a flood at the top BUT by the time the waters goes down the watershed the higher order streams won't flood as much because they can accomidate more water)

Answer 135

Can have immediate lower order streams flooded -- now have more water going down the chennel --> eventually the lower parts can be flooded BUT that flooding might be delayed becasue of the time it takes water go go down

Answer 136

Might have flooding upstream (immediate affect) --> eventually the water can make its way down and flood the lower parts BUT could be delayed because of the time it takes for the water to get ther e

Answer 137

1. What would originally happen in the water shed if there was not a town built there -- shows the natural response of the watershed as a whole 2. Shows the response if it is not in its natural state Example -- if there was a lot of buildings and roads and imperbale surfaces that result from humans building --> Now it is faster to reach the crest -- just runs immediatley to the watershed and stream system OVERALL -- show peak of flooding + how long it took to get to peak

Answer 138

Makes imperbale surfaces --> now the water runs immediatley into watershed and stream = the flood is faster to reach crest

Answer 139

Fluctuations in stream discharge ***Can be make whether it is upstream or downstream

Answer 140

Hydrograohs spanning long periods of time are usedful for constructing "normal" rates and amount of floods for a given streams ***Can keep track of stage of strom through the time + can compare years ***Can keep track of flood statistically (see how often a flood happens)

Answer 141

Statistics -- based on statistical predictions of how often it is likely a place will be flooded - Flooding is often discussed in terms of statistical frequency of flooding events of differing severity ***Uses Hydrographs

Answer 142

Normal is no longer neccessarily normal --> frequency at which flooding events happned in the past is happening more and more frequentley in recent times

Answer 143

Frequencey at which flooding events happened in the past is happening more and more frequnetley WHY??? -- has to do with the fact that large precipitation events are occuring more and more frequnecty --> has to do with teh fact that the earth is warmer which leads to more precipitation events

Answer 144

Has to do with the fact that there are more large precipitation events --> Large precipitation event frequencey has to do with the fact that the earth is warmer

Answer 145

Has a weirdley big discharge event because of a large precipitation event that occured

Answer 146

Upstream has faster response AND shorter duration compared to donwstream floods

Answer 147

Had mudflow from Mt. Saint Helens eruptions -- filled a stream with ash and mush + had a long term increase in stream stage

Answer 148

Show discharge as a function of recurrence interval for a particular stream or section of one.

Answer 149

How frequently a flood of given severity occurs on average for that stream

Answer 150

Smaller end of the flood scale = best constained by datat -- data for flood levles that occur every 100 years is less avalble ***Have more data for floods that occur more often

Answer 151

Can also be discussed in terms of the probability that a flood of a given size will occur in any one year ***Probability it will occur during a particular year

Answer 152

Planners and scietists use the information tp designate 50-year flood plains

Answer 153

DO NOT guarantee that a 50-year flood will not occur more than one time within 50 years ***Especially because becoming more frequent

Answer 154

With global warming -- floods in many areas are becoming more sever + more frequent ***Have more moisture in atmosphere because of warming of oceans --> Leads to more precipitation = have more floods

Answer 155

Shows discharge of stream + the probability of the flood in X number of years Example -- looks at discharge -- can expect a flood of that magnitude every X number of years ***Can convert percentage into probability ***Have more data for smaller floods

Answer 156

Smaller floods occur almost every year Vs. bigger onces occur less often

Answer 157

Have more data for smaller floods -- because they occur more often

Answer 158

1. Can have damage 2. Can have loss of life 3. Building on floodplains = can exacerbate flooding

Answer 159

Building in flood plain = can exacerbate flooding (increases flooding)

Answer 160

1. When building a town --> you are convering up the permeable ground (when have rainfall the rain can soak in) --> convering it with impermable surfaces (covering with asphalt + concrete) -- THIS increases runoff to watershed during the rain event - reduces water infultrayoon + increases overland flow that goes to streams and rivers 2. Buildings and fill material used to levle the land all take up volume (it is now space that water can no longer fill) --> makes the water level rise 3. Towns drain strom water --> when there is heavy rain they drain water to steam because the water goes to fast to be able to drain it away from the twon = the channel gets more flooded

Answer 161

Raised banks along a stream channel

Answer 162

Levees form naturally during flood events as sediments suspended in the water is deposited at the channel edges during floods

Answer 163

Levees may be artifically enlarged or created by people to try and contain flood events in a channel

Answer 164

Can artifically enlagre Levee to try and contain flood events in teh channel

Answer 165

As water leaves the banks during a flood it carries sediments with it -- when in a stream the sediemnts all go in ONE directions BUT during a flood event there is a pool of water AND the foward current of the stream is NO LONGER only in one directions it is also flowing towards the side and going over the banks BUT when it goes over the banks it still has sediments -- sediments are carried up to the sides BUT do not have as mouch velocity as when it was only going in one directions = they get deposited --> After successive flood events = get depsoits of sediemnts alongside the chanels that build up over time -- builds slightley raised areas on either side of the chanel

Answer 166

1. By not letting water escape you get a bakcup upstream of water that is trying to flow down = causes upstream to rise more = get flood 2. Raisning = trying to chanel the water through instead of flwoing out and over BUT that water now goes downstream = get more flooding downstream because have more water going downstream 3. If the Levees do get overtopped them sometimes the water escapes --> when the rain stops the flood can receed BUT the water that has escpaed and pooled up now has the Levee in the way and can't receed as fast into the chanel = makes the flood waters stick around for longer

Answer 167

***New Orleans -- has issues with flooding + Costal processes Had artificial Levees -- during Hurricane had strom surge that flooded the city - They keep the city dry with Levees and pumping systems where they pump water out of system to leave the city BUT the strom knocked out the pumping system and flooded over the Levees ***Knocked out pumping system + the water went over the Levees --> water just sat in the cities and neighborhoods for a while -- water in neighborhoods was behind the Levees = couldn't drain back = the water just sat there

Answer 168

1. Knocked out the water pumps 2. Water went over the Levees = the water just sat there and could not drain back

Answer 169

Coasta areas = tend to be the densley populated areas - About 44% of the world's population lives within 150 km of a coast - Coastal areas are getting crowded + their natural resources are under increasing pressures

Answer 170

1. Active Margins 2. Passive Margins

Answer 171

Coastlines located on active plate bounderies where subductions or transform faulting is occuring

Answer 172

Active plate bounderies -- Subduction or Transform faulting ***Oceanic subducting under continent --> causes uplift of continent in many cases

Answer 173

West Coast of U.S.

Answer 174

1. Narrow continental shelf --> water gets deep fast 2. Often cliffs above waterline 3. Erosional coast 4. Sea cliff -- with small areas of beach (different topography than the east coast) 5. Oceanic subducting under continent --> causes uplift of continent in many cases

Answer 175

Water gets deep fast --> less gradient as you move off shore

Answer 176

Areas where there is subductions -- the land is being uplifted --> uplift that is occurring puts the land above sea level -- ocean is trying to erode = gives sea cliff erosional features

Answer 177

Areas where the land is being upflifts --> uplift puts the land above sea level --> ocean is trying to erode at the land = creates the cliff erosional features

Answer 178

Coastlines located where oceanic crust transitions to continental crust with NO collisions or subduction

Answer 179

1. East Coast of the U.S 2. Gulf of Mexico

Answer 180

1. Broad continenta sheld -- extends for some distance offshore 2. Broad beaches + sandy beaches 3. Sediments are being deposits on the beach --> gets moved by the ocean crust 4. Often have sandy barrier islands off shore -- sand being deposited by rivers 5. Have gentley sloping beaches 6. No subduction -- not a plate boundery -- oceanic crust transitions to continental crust without collision or subduction

Answer 181

Have more deposition of sediment than on active margins ***Sediments get moved by the ocean current

Answer 182

Gently Sloping surface washed over by waves + covered in sediment

Answer 183

Sand may be produced locally by wave action OR deleivered to the coast from inland streams and rivers

Answer 184

Have different grains of sand based on where you are --> The grains all go to where they are in equilibrium -- depends on the energy and the water conditions

Answer 185

Beaches are shaped by the waves and currents -- the beach at any given time represents an equilibrium condition of sediment relative to the wave and current conditions

Answer 186

1. Mean Low tide 2. Mean High tide

Answer 187

OCEAN --> Beach face (mean low tide + mean high tide) --> Berm --> Dunes - Dunes = at the back of the beach

Answer 188

Found at the back of the beach

Answer 189

Waves are induced by flow of wind over the surface of the wave --> waves are driven by the flow of wind over the surface of the ocean

Answer 190

Gravitational pull of the moon

Answer 191

Tides -- due to pull of moon Waves -- due to wind on the surface of water

Answer 192

If look at one molecule of water --> it makes little circles ***Individual water molecules actually rise and fall in circular orbits that get smaller with depth

Answer 193

As you go deeper -- the circle gets smaller ***At a certain depth the circle is negligable

Answer 194

The depth depends on the amplitude of the wave above the surface

Answer 195

As the wave comes to the shore it reaches a poiunt where the based interescts sand on the beach offshore --> when intersection occursit causes drag on motion at the mottom of the wave base -- as you go shallower the wave base itersects the ground = the wave breaks because the bottom is slwoing down relative to the top = it leaves foward and the wave breaks

Answer 196

When the bottom of the wave intersects the sand --> the botton loses motion = the bottom starts moving slower than the top = the top topples over and the wave breaks ***When water shallows to the wave base the wave breaks

Answer 197

When water shallows to wave base

Answer 198

Depth at which water motion is negligible

Answer 199

Water levels relative to land elevation varies over time ***Have short term change and long term change

Answer 200

1. Spring Tides 2. Neap Tides

Answer 201

Spring Tides -- Earth + Moon + Sun are aligned --> Have highest tides Neap Tides -- Moon and sun at right angles --> Low high tides - When at the sides the water is still pulled because of the sun's gravity BUT the sun is farther away than the moon = it gets pulled less

Answer 202

1. Tides -- tides change based on time of month 2. Storms

Answer 203

Tides change based on the time of the month -- during certain times of the month there are higher and lower tides - Depending on where moon is in its phases -- affects how higher the moon is at high times ***All has to do with where the moon is located

Answer 204

Global sea level through geologic time has NOT been constant

Answer 205

Time where Ice sheets are expanding = sea level goes down VS Ice sheet smelting = sea level increases ***NOT just water being release or trapped in ice BUT ALSO because warm water expands

Answer 206

Warm water = expands --> as oceans get warmer have THERMAL EXPANSION of the sea water -- same mass BUT takes up more volume

Answer 207

Even though in total there is global sea level rise IN some areas the coeast lines are rising (sea level decreases) -- In some areas the coast lines are going uop because of tectonics pushing them up at a faster rate thna sea level rising = in those areas the sea level is not rising ***In these areas -- the net affect is that the sea level is going down ***Not in most of the world BUT occurs in places with convernnet bounderies OR Tectonic processes can cause sibsidence -- sea level is rising faster than in other places ***Tectonic processes cause plates to uplift + Subside + Buldge

Answer 208

Occurs when the tectonics pushes the continental plates up faster than sea level is rising = net decrease in sea levle in those places ***NOT the global trend ***Occurs in places with convergent bouderies Example -- PNW

Answer 209

1. Can have subsidence becayse you are built on a place that is built on sediemnts and the sediments compact over time which causes subsidence 2. People pumping water out of sediemnts = causes sediemnts to compact -- places that fluid used to occupy goes down and fills space = get subsidence

Answer 210

PLeases where sea level is increases relative to coast elevation ***Can have tectnonics + Subsidence + Eustatic sea level rise

Answer 211

1. tectonics 2. Subsidence 3. Eustatic ***Drownded river valleys/mouths = typical features

Answer 212

Global changes in the height of the ocean that primari;y result from chnages in the volume of water locked up in glaciers or ice sheets + due to the thermal expansion and contraction of water

Answer 213

1. The change in volume of water locked up in glaciers or ice sheets -- water melting and going into oceams -- polar ice and glaciers melt during warm climates 2. Thermal expansion and contraction of water -- water expands

Answer 214

We are still in a relativley cold period BUT we are coming out of it faster than we suually would because of global warming and greenhouse gasses BUT that doesn't mean we haven't seen these temperatures before

Answer 215

Relative rise and fall in sea level affecting a loval or regional area - Regional = due to regional tectonic effects such as regional uplift or subsidence of a coastal area

Answer 216

Relative sea level change may differ from the trends occuring globally at the time ***Sea leveldoes not rise equally in all places

Answer 217

1 foot per Centery

Answer 218

Doesn't sound like a lot BUT that change is verticle -- when a shallow dipping coastline has one foot of verticle chnage in water depth it translates to a LOT of land area that will be submerges ***In places like the east coast where the shore is shallow sloping gradient -- if you increase by one foot vertically then you cover a lot more land + IS AN isse because a lot of cities are on coasts in places with shallow gradients

Answer 219

A small rise in sea level results in larger inland retreat of the shoreline -- especially in gentley sloping areas ***Most coastal areas are gentley sloping or nealy flat - rates of shoreline retreat can be several meteres per year in low lying coastal areas

Answer 220

Rates of shoreline retreat can be several meters per year in low lying coastal areas

Answer 221

Most of the east coast is at risk for sea level rise

Answer 222

If look at a century of data --> have 7-8 inchens in one centery BUT if look at 2000-2020 you already have 4 inches in JUST 20 years ***Means the line of sea level rise is getting steeper because the sea level rising rate is increasing over time (The sea level is rsing faster now than it was in the past)

Answer 223

In Southeast Lousianna --> Sealvel rising 3 feet every 100 years (rising faster) - Result of subsidence of the Mississippi delta + glbal sea level rise - Can be due to the loading on the continental shelf by ice + sediemt - Can be due to human extraction of groundwater or oil from the subsurface

Answer 224

Where water comes into the atlantic ocean -- as the sea level rises the water flows into depression and fills it up

Answer 225

Where a river used to be flowing and as sea level risiong it floods and fills river valley to make an Estuary

Answer 226

Global sea level has varied wideley in geologic oast and has been influenced by many climatic events that have affected ice sheet volume + also affected by tectonic provesses that control the hsape and colume of ocean basins as continenents have shifted amount difefrent geographic arrengments ***Global sea level = affected by ice sheet volume + Tectonics - Graohs = made by where you find marine sediemnts Overall - for most of geologic time sea level has been higher than it is today

Answer 227

We are in a LOW sea level time right now -- most of the time in the past the sea level was higher than it is now ***We are stilling coming out of the last ice age -- there were warmer times in the past where there was smaller ice sheets (we are in a cold period still)

Answer 228

YES -- global warming caused by human activity is still true (even though we are in a cold time) -- by burning fossil fuels we are increasing CO2 and greenhouse gasses = casuing the atompshere to trap more heat in --> causes the ice caps to melt faster than they normally would + casuing oceans to be warmer faster than they normally would - As the poles warm faster and ice melts faster and as oceans warm fatser the sea level rises faster than normal

Answer 229

When we talk about global warming we are talking about human time scale BUT the earth doesn't care about humans ***earth doesn't care about warm temperatures now because the earth has been warmer than it is now

Answer 230

Glabal warming of earth -- the erath doesn't care because it has been warming and it doesnt care about humans BUT humans care because the chnages affect humans ***Glabal warming doesn't matter for earth but matters for humans

Answer 231

1880 -- start to see sea level rising faster --> occurs because of the start of the industrail revolution - Pre 1880 - less emission of greenhouse gases - 1880s -- get chnage in sea level trend --> now sea levels are risning faster 1920s -- now have cars + pumping things out of the ground = sea levels rise even more -- have another chnage in trend ***More recent sea level has been rising at increases rate since the 1800s compared to a relativley stable period that persisted for the previous thousands of years

Answer 232

Sea levels begin rising faster -- because of INDUSTRIAL REVOLUTION -- now putting more greenhouse hasses into atompshere

Answer 233

Have another change in trend --> sea levels rising even faster -- because now have cars + are pumping things out of the ground

Answer 234

More recent sea level rising has been at increased rate because of industrial revolution + cars

Answer 235

1. Southeast U.S 2. NYC

Answer 236

Southeast = more susceptible to effects of rising sea level because has very low graidents + have a lot of cities that are right on coasts - In 2100 --> miami is gone + jacksonville is flooded + virgian beach in flodded - in 600 years -- 1/2 of florida is gone

Answer 237

1. Because very low gradient 2. Have a lot of cities that are right on coasts

Answer 238

BIG issue because a lot of our cities are on coasts -- in places with shallow gradients = suceptable to big rise in sea level (small vertcal changecovers a lot of land) ***Issue because a lot of people live in low lying coastal areas

Answer 239

Thermal Expanssion (not talked about as much BUT it is the higher driving force)

Answer 240

1996 - 2003 --> 0.42 mm per year JUST in last 10 years --> 1.3 mm per year ***Shows that thermal expansion is becoming more and more important as time goes on + shows that the rate of sea level rising is faster as time goes on

Answer 241

1. Floods of low lying areas 2. Increased susceptibility of coastal communities to flooding during storm events/surges + Increased Frequency of Hurricanes 3. Increased beach and shoreline erosions and instability of beaches 4. Seawater intrusion into freshwater supplies like groundwater aquifers

Answer 242

Places where we are used to having beaches on the east coast -- fighting back against erosion to keep the beaches because the ocean wants to take over the beaches + as sea level rises the current wants to take the sand away

Answer 243

Miami -- very susceptible to rising sea level because its low lying and flat --> aquifers that they pump to get freshwater to drink is being intruded by salt water from the ocean + ALSO occurring in South Carolina

Answer 244

Places where the sea level is decreasing relative to coastal elevation - Usually implies that tectonic processes are uplifting the continental plate in that area relative to sea level

Answer 245

Usually implies that tectonic processes are uplifting the continental plate in that area

Answer 246

Wave cut platforms -- feature that can result from emergent coastlines

Answer 247

Important component of the way that beaches are eroded

Answer 248

Wind -- as wind moves acorss water is causes drag --> drag makes water move

Answer 249

Moves in circular pattern --> series of circular pattersn as you get deepr get less intense until you get deep enough that the motion doesn't happen

Answer 250

As you go deeper the motion gets less intense

Answer 251

When the wave gets to the beach it intersects the beach and creates a drag at the bottom = causes the wave to break - Water hits the beach at the base = makes the wave topple and break ***When wave approaches shallow water at a depth 1/2 of its wavelength

Answer 252

Usually 1/2 the wL between the different waves Example -- If the wL is 10M then the depth where the wave will break is 5 Meters

Answer 253

When the wave breaks -- have string current intersecting the sand/beach --> wave moves sand each time the wave comes in ***Each breaking wave moves sediment

Answer 254

Waves rareley apprach shoreline straight on -- they usually come in at an angle -- they come in at some angle to the coast line ***They usually come in at the same angle each time

Answer 255

Causes Longshore Transport of Sediements -- because of the angle they make a current that corresponds to the direction of the waves hitting ***Current that it creates = longshore current

Answer 256

Moves sediments in the direction of the current -- moves sediments more inland down the beach = causes beach erosions ***Sand moving along the shore face in a direction determined by the angle of the wave approach -- has to do with the way that waves come in

Answer 257

As sea level rises it causes long shore current to move sand more and more inland = makes beach erosions ***STILL have long shore current wether or not sea level is rising

Answer 258

Topographic features that “jut out” into the surf zone and are more susceptible to erosion

Answer 259

Waves are deflected around and toward headlands because the waves approaching the headland “touch bottom” first and slow the waves down near the headland

Answer 260

Waves get refracted in one direction depending on the topography of the beach

Answer 261

When waves approach beach at an angle (almost always) water moves laterally in a current along the shoreline

Answer 262

Sand movement along the beach in the same general direction as the motion of longshore current. ***Sand is continuously being transported usually in a constant direction for any given beach. - Is the ACTUAL sand movement in the direction of the longshore current - The direction usually stays the same

Answer 263

Planners try. andcombat longshore current -- they build something perpendicular to the beach to trap the sand and stop the flow downshore - Build Groins/Jetties to stick off the coast and trap the sand

Answer 264

Man made features that try and slow beach loss/erosion by trapping sand being transpoirted by littoral drift

Answer 265

Usually causes eorsion down current from where it wa sbuilt ***Creates build up of sand on one side and then on the other side there is a lack of deposition downstream of jettir = have erosion downstream of the jettie

Answer 266

Upstream -- have beaches Downstream -- Sediment starved

Answer 267

1. RipRap 2. Seawalls 3. Breakwaters

Answer 268

Piling big rocks around the base of. abuilding -- so that as sea level rises and as long shore current erosion occur you can slow eorsion to buildings ***Fors for a time BUT is temperary

Answer 269

Building a hardened structure ***Temperary fix

Answer 270

Biulding hardened structures offshore that are PARALLEL to shore lines -- defelcts waves away from property ***Trying to build structures offshore that block waves from hitting the shore - Slows eorsion immediatley behind the structures BUT they chennel current to either side of teh sturcture which increases erosion in those areas

Answer 271

Trying to stop waves from being able to hit the short

Answer 272

Slows erosion immediatley behind the structure BUT they channel currents to either side of the sturcture = increases eorsion at the sides ***Works immediately behind BUT the water is just deflected to either side = causes more erosion between the breakwaters

Answer 273

Beach nourishment

Answer 274

Placement of sediment ***Beaches being eroded away -- solution is to pump more sand onto it

Answer 275

Not a permament solution -- erosion will continue ***Sand is leaving the beach for a reason -- by trying to replace the sand it will be wahsed away anyway = beach nourishment can only last for a little while

Answer 276

Increasing disconect with hard structure by manicipalities

Answer 277

The sand that is pumped onto the beach from offshore MUST be the correct grain size to be in equillibrium with the waves/current condistions ***Can't just pump sand onto the beach -- needs to be the correct grain szie --> if its not the right grain szie then it will just wash away very fast becasue it wont be in equilibrium with the waves coming in

Answer 278

1. Rising sea level 2. Sinking coasts 3. DImished sediment supply 4. Strom activity

Answer 279

The sand on the beach is dervied from rocks on the top that have been weathers (sand comes from weathering from the continent) --> sediments are bring transported and deposited --> IN the modern world riovers between the ocean NOW have dams -- behind the dam have an accumilation of sediemnts = less sediment is reaching the coast

Answer 280

Long term -- Slow landward march Short term -- storms + changes in waves + climate + sediment input

Answer 281

Moved the Cape Hatters lighthouse ***When they built the lighthouse it was NOT right in the beach it was several miles from the beach BUT now it is on the beach = they moved the lighthouse more inland -- did it on rain track

Answer 282

Bars of sand -- Long + Low + Narrow offshore islands that paralell the coastline slong a PASSIVE margin - They are swamping -- low gradient -- close to sea level with lots of swamp land

Answer 283

Outter banks

Answer 284

The exact way that they form in not completley understood -- seems to involove transport of sand by longshore current during times of changing sea level

Answer 285

They form on depositional coasts -- form on costlines that have abundent sediemnt supply ***Form in places with lots of sand + passive margins ***Get ribbons of samd that form offshore

Answer 286

Passive Margins

Answer 287

1. Provide a variety of habitats + ecosystems - in places where they form they form a barrier between the ocean --> forms unique envirnments behind them ***Important place for fish to lay eggs + important habitate that fish have adapted to live. in 2. Protective barrier from stroms -- provide important protection from storms

Answer 288

Seem to be associated with rising sea levels + form on shorelines with lots of sediemnts ***Seem to form at times of rising sea level BUT the reason why they form is not fully understood

Answer 289

Estuaries + Maritime forests + wetlands

Answer 290

Have beach -- typical beach profile

Answer 291

When tide goes up the ocean wateer goes in and out through the inlets BUT also have freshwater coming in from the rivers on the continent

Answer 292

Have a mixture of fresh and sea water = have estuary

Answer 293

Mix of salt and fresh water -- forms behind barrier islands --> is important for fish ***Salinity of water is a mix between the two

Answer 294

Barrier island = important place for marine fish to lay their eggs + important place that they have adapted to live in

Answer 295

Tidally controlled water body open to the sea where fresh and saltwater mix (brackish) ***Water behind barrier islands = estuary - Genrally refers to a place where you have a mixture of seawater + freshwater coming together

Answer 296

Important coastal environments and breeding areas for marine species ***Estuaries have plants and organisms that are unique for envirnment

Answer 297

Chesapeake bay (drainage is draining into the chesapeake but the tides bring in saltwater = have a mixture) + Pugent Sound + LI Sound

Answer 298

Tidal inlets -- tides can bring ocean water in through Tidal inlet

Answer 299

1. Barrier island themselves -- Beachs + Sand dunes 2. Backsides = have maritime forests + Swamps 3. Terrestrial 4. Marshes 5. Wetlands on coast ***Barrier islands system = have Inlet --> Stroms/wahsover fan --> Marsh --> Shorline --> Fore fune --> Meach and dune reidges (Left to roght) Have Marsh + tidal creek behind the barrier island

Answer 300

Shrubby trees

Answer 301

Along the U.S coast + the gulf coast

Answer 302

Barrier islands = dynamic systems that are constantley moving in repsonse to chnaging sea lebel + are often overhwashed in places during large strom events ***Barrier island is not staionary through time

Answer 303

1. Chnaging sea level 2. Places are often over-washed in large storm events

Answer 304

As sea levels increase they tend to move inland (towards land) + the placves where tiodal inlets are found migrate through time

Answer 305

In places with large barrier island -- people might build roads + bridges over the todal inlets BUT the bridges can be taken down by hurricanes ***Barrier islands = not very good places to build things on

Answer 306

The tidal inlets can migrate (espcially during stroms) + new ones can form in plaves where they were not found before

Answer 307

Barrier islands = NOT very good places to build on -- there are some places that are more stable + prtected from hurricanes and storms BUT people like to live. oncoastlines where it is less stable

Answer 308

There are buildings right. on the beach BUT those are sucpetable to being knocked over during stroms

Answer 309

Sometimes during large storms -- barrier islands are breached and a new tidal inlet may form

Answer 310

Older settlements = located behind the dune crest -- more stable New development = often on the more unstable beach front

Answer 311

Lagoon sediemnts --> Subtidal --> Low tide flats --> peats --> Salt marshes --> barrier flats --> dunes --> Nack shore --> foresore --> nearshore ***Look at image in notes

Answer 312

Because of longshore drift

Answer 313

Reason why barrier islands migrate during sea level rising --> Sand deposits get sediment over where you have grasslands. and marshes behind the dunes = pushes everything back inland

Answer 314

Overwash fans -- reason why barrier islands migrate during sea level rising --> Sand deposits get sediment over where you have grasslands. and marshes behind the dunes = pushes everything back inland

Answer 315

Stuff falls downhill ***Big engineering problem in places with steep topography - Not a huge problem in Binghamton

Answer 316

1. IN bay area in California 2. Problem around roadcuts because roadcuts are steep features

Answer 317

Movement of geologic material downslope in response to gravity ***Includes subsidence and collapse due to sinkholes

Answer 318

1. Slow and cumulative -- soil creep 2. Sudden and swift -- rockslides or avalanches ***Includes subsidence and collapse due to sinkholes

Answer 319

Soil creep

Answer 320

Rockslides + Avalanche

Answer 321

In areas with large topography -- have cavses undergdoun in the bedrocks --> when water moves through the caves = can have collapse = get sinkholes ***Sinkholes = included in type of mass wasting

Answer 322

General term for the results of RAPID mass movements

Answer 323

Casues over 1.5$ Billion in prpoerty damage AND 25-50 deaths in the U.S each year

Answer 324

1. Bay area -- has more landslide potential 2. West virginia -- have appalachian which are very step (most twons are built in mountainous valleys)

Answer 325

1. Things that decrease friction (WATER) 2. Angle of the bed rock - if slope becomes steeper 3. Increase mass 4. Weathering of material (breaks loose = slide)

Answer 326

Whether things start sliding down a slope is about the equillibruim between the pull of gravity and the thing holding it in place

Answer 327

Mass + angle of the slope

Answer 328

Things move when sheering stress exceeds sheer strength

Answer 329

When water fills the pre space AND you have wtare on top = creates a pre ssure that pushes on partciles = pushes them away from eachother ***Makes things slide more

Answer 330

A LITTLE water = can be cohesive ***Surface tension made by a little water that binds particles together

Answer 331

A LOT of water --> holds sediemnts aparts + provides pre pressure that pushes. thesediemnts away from each other + LOTS of water also provodes lubrication that allows particles to move more easily ***Water is a big factor in landslides

Answer 332

If you have a fracture that is exacerbated by freezing and tawing of ice or by tree roots --> THEN layer is fractured = makes it steeper = increase movement ALSO when you fracture you now have somthing that is different composition below you = move more

Answer 333

Couldm be from erosion or tectonic uplift --> casues more movment OR Can have human activities that change slopes

Answer 334

Weathering material by water or ice = causes things to break loose = they sldie

Answer 335

If you are making a roadcut fir a highway OR if you are trying to level a part of a hillslide for road or house --> MIGHT affect slope = can make a situation where the slope is not stable anymore

Answer 336

Changing slope of hillside to make space to put a road

Answer 337

Mass movements occur when downward pull of gravity overcomes frictional forces resisting it

Answer 338

Downslope pull related to mass of material and slope angle

Answer 339

Counteract shear stress

Answer 340

1. Lubrication by water/fluids 2. ncrease of pore pressure in saturated soil/sediments 3. Bedding planes in sedimentary rocks, or clay layers

Answer 341

1. Mass of water 2. Weathering (breakdown of rock by water, wind, ice) 3. Steepening of slopes due to erosion or tectonic processes

Answer 342

1. Factors that decrease friction 2. Factors that increase shearing stress

Answer 343

Damp sand = sticks together --> a little water is good Dry = bad -- wont stay together Completely saturated -- ALSO bad -- even worse than dry --> too much water between the grains lubricate them

Answer 344

If there is more waterlogged soil about the already went soil that have water in the pore space = the waterlogged soil above pushes on the pore space of. thesopil below it = now adds pressure below it = now have pressure in all directions. =pushes things apart ***During rainstorm the combined affect can cause the soil to slide

Answer 345

Maximum slope angle at which a material is stable ***It is the unconsolidated material’s resistance to sliding -- varies with the material - It is the angle that you can pile the material in

Answer 346

Course Material (more angular) -- can be piled up more steep and still be stable Finer rounder -- Angle that you can pile them is slower

Answer 347

Binghamton -- They widened the area of 201 to get off exit to get off vestal --> In areas where they did it it looks like they dig out hole and put rocks. inhole because they did - Issue: They built a slope angle that was too steep for the materials angle of repose and they got slumping occir and parts of the hill was sliding Solution: They scopped out areas that were slumping and put a boulder there -- put courser thingh that can be stakced at a steeper angle

Answer 348

Slumping can occur ***Occurred in Binghamton

Answer 349

Have sediments that are flowing out

Answer 350

Fall at the speed of gravity -- very fast

Answer 351

IF still in contact with the surface below -- Includes rock slides + Soil slumping

Answer 352

Includes snow avalanch + avalache of dirt and debri + mud flows ***Has things that are mixed with water to some extent = makes it flow ***Can refer to chatic movemnt of dirt and consolidated debris

Answer 353

Can refer to the chaotic movement of dirt and consolidated debris

Answer 354

Slowest version of mass movment (less than a centimeter per year) -- takes many years to see efect - Soil is slwoly creeping/flowing in a slow way downhill

Answer 355

Usually takes place with seasonality -- freezing and thawing - Freezing = water expands = prys patrtciles loose --> when it melts it contracts and the hole thing moves ***Almost like waves ***Could just be ebcause of a lot of rain OR could be if. theslope is really steep

Answer 356

1. Creep 2. Falls 3. Slides 4. Slumps 5. Flows

Answer 357

Can be in soil or rock -- very slow downhill movement of soil or rock mass - may be driven by frsot of hevy rain or because of contant stress - Indiviudal movements are short diatnces and the porcess is slow -- cumalative efect over the years can cause property damage

Answer 358

1 cm per year

Answer 359

Slope of five degrees or a little more

Answer 360

May be driven by heavey rain or in repsonse to contanst stress

Answer 361

Indivdiual movement -- short distances and the procvess is slow Cumalative effects -- can cause property danmage

Answer 362

If you have a building where creep is happening -- can cause foundations to crack and be damaged

Answer 363

Free falling material that is not in contact with the groundwater surface

Answer 364

Usually occur. onvery steep slopes where weather breaks up rocks high on sleop and erodes away the materials below them ***Common along rocky coastlines (wave erosion of cliffs) + on road cuts - Happens around cliffs -- seen in erosional cliffs along shorelines --> ocean undercuts cliff phase

Answer 365

Much faster (esocially than creep)

Answer 366

Coarse material that accumilates at the base of a slope due to rock falls

Answer 367

Example rock falls Type of Granie that forms with a lot of fractures between -- over the years it erodes and peices break off and make rock falls

Answer 368

Fairly cohesive unit of rock or soil slips downward along a clearly defined surface or plane.

Answer 369

Along bedding plane is sedimentary orck or contant between rocks of difefrent compositions

Answer 370

Charachetrized by translational movement. inone direction along a plane

Answer 371

Because there are layers --> they can be inclined -- if the diferent composition of rocks are in contact AMND then you have mechinacal weathering in one layer and fracture forms = a portion of. therock layer that lets loose slides on material below it = now have rocks of diofefrent composition on top of each other = get motion

Answer 372

Rotational movement of soik mass during downlope movement

Answer 373

Occur in soil

Answer 374

Scarp forms at the top of slumps -- top surface of slump may remain intect with flow at the bottom

Answer 375

rotational movement

Answer 376

Movement of unconsolidated material along a plane, but not as a coherent unit. - Movement is chaotic and disorganized with mixing of particles similar to a fluid.

Answer 377

1. Soil earth flows (dry) 2. Mudflows (wet) 3. Snow avalachnge 4. Debris avalanche 5. Pyroclastic flows

Answer 378

Soilflows = dry Mudflows =wet

Answer 379

Venezuela -- city. atthe base. ofmountian --> 30,000 deaths and deceminated city due to flows

Answer 380

1. Clearing away stabilizing vegitation (deforistation) 2. Over-steepening of slopes during construction of roadcuts, quarrying, stepped lots on hillsides 3. Building on sleops and adding weight 4. Removal of material at base of dipping rock layers 5. Adding water to slope by lawn watering + Spetic systems + swimming pools

Answer 381

MIght amke stepps in lots. inhillsides -- make steps. inteh side of hill to make a place to build houses ***Removes stabilizing rocks and soils that would noramlly be there --> make steeps lides betyween each of the flat steps

Answer 382

1. Oversteepned slope 2. take away stabilizing material

Answer 383

California -- where land is at a premium

Answer 384

Often build a retaining wall to hold material behind the places you are making a cut -- how effecting this is depends on the situation + how well engineered it is + ultilmaetkley this is a point where it will be too steep and is unstable

Answer 385

1. Slope reduction/stabilization 2. Retaining structures 3. Fluid Removal 4. OTHERS

Answer 386

Move soil/rock to reduce the slope angle or place supporting material at base of slope – Regarding the slope - Can reduce the gradinet of the hillseidfe above roadcuts or if making steps ***Removing material. =makes less steep BUT also makes less weight

Answer 387

Retaining walls or stabilization structures, mesh nets ***If have roadcut = might have mesh to hold things from going to road and hitting cars + Might put imperbale things to stop from sliding and slumping

Answer 388

Strategies to decrease water content and pore pressure in a slope with enhanced drainage - Might put in drains to drain. tehwater out so that it doesn't become waterligged druing rain events ***Might do where you have pore pressure building

Answer 389

Rock bolts + Anchor cables + Vertical piles + Hardening slope surface with concrete - Mght have a weird screw thing --> drill into rocks and put a cable and anchor it to more stable rock underneath it - If there is loose material --> might just build. aconcrete layer on top --> just put a shell of concrete to reduce tge amount of unconsolidated material that will go tinto the road each time there is a rain strom

Answer 390

Mass of ice that moves over land under its own weight in response to Gravity.

Answer 391

Ice flows in repsonse to gravity -- glacier move down slope in the same way. aswater BUT they. donot move as fast as water does

Answer 392

They move from greater thickness of the glacier outwward

Answer 393

Found in polar or arctic regions + in other regions. athigh altitudes

Answer 394

Can have a glacier NOT near the poles if it is at a high altitude Example -- Glaciers in east Africa -- they are near the equator but are over 15,000 feet in elevation (near equator BUT at high elevation)

Answer 395

Glaceiers form when winter snowfall exceeds summer melting -- have net increase in snow over time ***Most start as snow matches in the mounatins that survive the summer on slopes that are protected from the most direct sunlight. - As snow accumalates over the years = it becaomes compacted with each xnowfall = gets compacted into ice = forms ice

Answer 396

Areas of the mounatin that are protected from sunlight. =have less melting in the summer

Answer 397

Can occur over seasons OR can occur over thousands of years -- depends on climate and the rate of accumulation

Answer 398

Evenetually the mass becaomes large enough that the ice will flow downhill OR outwards from the thickest accumalation (when its on level ground) ***Flows from thickest areas -- even if it is on level ground

Answer 399

Can vary -- from meters per year to 10km per year ***If its in a steep area with lots of snowfall = it can be 10. km per year (fastest)

Answer 400

Still coming out of last ice age -- still. ina cold period ***Humans affects how fast we are coming out of the cold period

Answer 401

Have warming of oceans + mealting ice sheets + drying out of arears (making more desserts = have more fires)

Answer 402

1. Alpine Glaciers 2. Continental Glaciers

Answer 403

Smaller glaciers that occupy valleys in mountainous terrain. ***Most glaciers today are this type

Answer 404

Alpine glaciers -- more abundant by number

Answer 405

Glaciers in mountains

Answer 406

Ice caps or ice sheets that cover large areas of continents and can reach thicknesses of > 1 km - There are fewer of them BUT they comprise much more ice

Answer 407

Greenland and Antarctic ice sheets

Answer 408

Antartica + northern hemisphere during the pleistocene

Answer 409

Has sharp peaks because glaciers carve valleys as they move

Answer 410

Ice + Sediments

Answer 411

Glaciers = have sediemnts + rocks --> material that is being eroded off of. theground that they are moving over ***Images have dark lines + bands in alpine glaciers ***Sediemnts get deposited at the edge of glaciers --> get charcahteric types of glacial deposits

Answer 412

NOT carrying them in susoension (like water) + not in a river bed (like water)

Answer 413

Glaceirs can pick up anything of any size -- diferent than water

Answer 414

Glaciers - erosive agents that carve valleys in oceans

Answer 415

When they reach the point in lower latitude --> they reach a point where melting exceeds the rate of snow accumulation

Answer 416

If you have warmer years OR you have a trend of warmer climate then the glaciers start to rceed instead of advancing -- glacier reaches a maxium and then melts ***Sediments. getdeposited at the edge of the glaciers -- get charachteristics types of glacial deposits

Answer 417

When it contact with other rocks -- the firction between the rocsk and the ice makes part of the glacier flow slower than the ice in the middle because the middle is not in contact with rocks

Answer 418

Fastest rate of movement in glacier

Answer 419

Trying to reach an equilibrium ***Ice sheets move away from the thickest parts towrads the thinest in an attmpt to reach equillibruim

Answer 420

Glacier Flows like a river

Answer 421

When the Glacier. isin contect with other rocks the frictiom between the rocks and the ice meakes segments if the glacier flow slower than other parts of the glaceir --> the ice in the middle flows faster because it is NOT in contact with the rocks

Answer 422

In the middle of the glacier ***Analogous to a stream -- becvause the middle of the stream is the fastest

Answer 423

Middle -- because when on the sides there is frictional and drag effects ***Theoretical poles in the middle move teh fartherest in a given amount of time because the middle is not in contact with rocks

Answer 424

Based on various types of evidence we can infer the diresction of ice sheet movement

Answer 425

20,000 Years Ago

Answer 426

In the pleistocene (20,000 YO) --> at the ice age there was the maximum extent of ice sheet

Answer 427

Because there are femenents of ice sheets

Answer 428

We are still coming out of the last ive ige -- coming out of the ice age is a natural process

Answer 429

Started during. theindustrial revolution (200 years ago) ***Before the revolution the earthwas still warming BUT at a much slower rate

Answer 430

NOT the ice moving in reverse BUT the ice is melting faster than the rate it is flowing ***Have a net loss of ice material

Answer 431

Zone of acummilation -- Before (to the left of) the Equillibruim line -- have snow being added Zone of Ablation -- To teh right of the equillibrium lune -- now have snow lost

Answer 432

Have net loss of glacier --> as it gets warmer the equillirbuim line between the zone of accumilation and zone of ablation moves upwards. onthe glacier

Answer 433

A glacier can pick up eveyrthing -- wtaer can only pick up what it has enough energy for (water sediemnet size is affected by the velocity of teh stream)

Answer 434

Morraine at the furthest advance of the glacier reaches and deposits sediemnts at

Answer 435

Build up of sedimenys when the glacier reccedes

Answer 436

The glacier can go back and forth -- not just only receeding once it strats to receede --> means you have a series of morraines behind the terminal morraines

Answer 437

Morrianse behind the terminal morraine that result form a galcier moving back and forth ***Glacier can start to receed and then advance and then begin to receed against -- the seond recession would create the recessional morraines behind the terminal morrianes

Answer 438

Glaciers are receeding faster and faster. +there are more receeding over the last few decades - There are now less glaciers advancing and more retreating

Answer 439

1967 + 1975 --> in those years there was more galcial advance --> the reason is because had a lot of volcanoes erupting = the ash blocked sunlight = the earth was cooler

Answer 440

Used to describe the chnage in glacier mass ***Convertes the change in ice or snow to chnage in the equivilent amount of water - can think about it as the avergage overall chnage in glacier thickness in meters - m.w.e = majes meters of water equiviolent

Answer 441

Measured as the avergae change in thickness across the surface of the glacier - the chnage in ice or snow is converted to the equivilent in the same amount of water in m.w.e units

Answer 442

Morrianse are one of the ways we know how far ice sheets have receeded

Answer 443

Features -- just know that there are certain features that are associated with glaciers EXample -- Morraines

Answer 444

Masive amounts. of sediemnt -- glaciers can pick up anything -- means that they can move small grains and massive boudlers

Answer 445

Powerful erosive agent on the earth's surface -- they act as a massive converyer belt erpdinh and moving sediemt including small grains up to large boulders

Answer 446

Glaciers act like massive conveyer belts eroding and moving sediemnt

Answer 447

Deposited by the melt water + deposited by streams --> all sediemnts are carried out by the melt water and braided streams that are in front of the glkacier

Answer 448

Braided streams -- has massive amounts of sediemnts = braided ***Sedeimnts get deposited. bymelt water and the stream that exits the glacer (stream is a braided stream)

Answer 449

1. Till 2. Outwash 3. Morraine

Answer 450

Sediemnt deposited dircteley by melting ice at the end of the glacier - Includes sediemnt in the morraine itself + sediemnt bieng depoisted in front of the melting glacier

Answer 451

Water = sorted Glacier. =transprt by glacier does not cause size sorting or rounding oif the sediemnt grains -- til is usually poorly sorted and angular

Answer 452

usually poorly sorted (mixtyure of rock types) + angular ***NOt like water that is more sorted and rounded

Answer 453

Till that. istransported and redeposited by meltwater --> have braided stream in front of the glavcier

Answer 454

Landform made of till -- landform made by sedeimnt depsouts directelet by metling at the end of the glacier

Answer 455

By looking at where there are morrianes from advances of ice sheets over contiennets

Answer 456

There can be material that allow us to date the age of when the moriaine was forms Example -- if you have a plant in it then you can use crabon dating

Answer 457

Illanois -- have galciated parts that are flat verycause glaciers went over them - Moraines in Illanois represent the advance of sepoerate tongues of ice during the last ice age

Answer 458

Have lateral morainesa t the edges of glaceirs (at the sides of the glacier)

Answer 459

During the last ice age -- 20,000 Years ago ***Coincidentally the times that modern humans were evolving

Answer 460

Coincidentally was the time that modern humans was evoloving - Had ice birdges + trapped a lot of water = have lowr sea level

Answer 461

There were ice bridges + the ice sheets trapped a lot of water which lowered sea level since the water was not in the oiceans ---> low sea level allows for land bridges between rsussia and alaska = bnridge for humans to migrate out. ofasia and go to the ameiericas

Answer 462

Had land bridges during the last glacier extent nbevause a lot fo wtaer was trapped in the ice sheets which made sea levek lower = have land bridges

Answer 463

1. Morraine 2. Abrasion 3. PLucking 4. Glacial Striations 5. Calving 6. Dropstones

Answer 464

Erosion by. thescraping of ice and included sediemnts on teh surfcae underneath - Indicative of glavcial movement

Answer 465

Glaceirs bulldoze over things --> becasue the ice has sediemnts = the sediemnts can scrape across. thebed rocks that the glacier is moving icer = the caried sediemmts act liek sandpaoer = scratch the rock underneath = makes charachetistic scratched on the surface of the bed rock ***Things bavk be tajen off of the bedrock and then carried by the glacier

Answer 466

Shows glacial movement -- can see orientation of where glacier was moving + direction that glacier was moving

Answer 467

When bits of underlying rock are broken off and carried by the glacier

Answer 468

Paralell lineations on the underlying surface as glacier advances over it

Answer 469

Caused by the scrtaching of the surface by bits of rock carried by the glacier

Answer 470

Indictae the past presence of glaciers + the direction in which they flowed

Answer 471

Indictae the past presence of glaciers + the direction in which they flowed

Answer 472

A signature of ice sheet movement

Answer 473

Marine places

Answer 474

Dropstones

Answer 475

The process of iceburg material breaking off of glaciers when they flow into a lrage body of water

Answer 476

Stones that were incorporated into glacier/iceburg when it calved but are dropped out some distance from the shoreline as the iceberg melts

Answer 477

Dropstones are easily recognize because they are large boulders in otherwise fine graines marine or lake sediemnt

Answer 478

Have stones in glacial ice --> if the ice goes into a body of water --> peices of the ice sheet can calve off into ice burgs -- if the sgeet has rocks then the iceburg snow have the rocks --> the ice burg can float away --> as they flota away the iceburg melts = drops the rock -- rock ends up on the sea flood

Answer 479

Because the sedients depsoited off shore are usually very fine grained things that were carried by the ocean currents or the wind --> if the glacviers were in teh vucinty then glaciers might have large rocks -- the large rocks indicate there was a glacier because the rock would not have been able to travel down a stream = it needed to come from the glacier

Answer 480

Show that there where glaviers in that place at a certauin time

Answer 481

Ocean or large lakes

Answer 482

They found sropstones in lower latutides (near eqiuator) --> leads to hypothesis of snowball earth

Answer 483

Smooth valleys that makes U shape --> featyre = U-shape valley ***Alpine glaceris move through valleys = make U shape valley

Answer 484

Alpine glaciers

Answer 485

Were carved during the last glacial maxiumum --> low lying areas that got filled with water

Answer 486

Bowl Shaped depression at the head of the glacier ***Likes. Ushaoe but at the head of the glacier

Answer 487

Sharp ridge between glacial valleys ***LIke boundary between diffrent glacial valeys

Answer 488

Erosion by several glaciers around a single peak

Answer 489

When you have glaciers goung in different directions off of peak

Answer 490

When you have something that might not tell you directley what was the temperature but might tell you how much water was lcoked up at the time + what timeype of climate zone was fpind in areagion + might tell you have mucj CO2 there was in the atompshere or dissolved in the ocean ***When you have something that indirectlkey tells you something else

Answer 491

Determined by a lot of factors -- including the amount of greenhouse gasses + the amount of solar intensity

Answer 492

The absolute amount of radiation from the sun has varied through geologic time

Answer 493

Because of varaitions in the sun's intesity through time AND due to orbital forcinhg Mikankovitch Cycles (there are some varitions in the way that the earth orbits the sun and. onthe way that the erath spins on its axis)

Answer 494

100,000 Years -- (Circukar --> elipitcal --> circular = 100,000 years)

Answer 495

1. The earth orbits the sun -- sometimes its more eliptical and somes times its more circular -- varies back and forth between more circular and more eliptical

Answer 496

Elipitcal = points during the year where the earth is further from the sun Circular. =constant diatnce from the sun

Answer 497

See the biggest effect in the polar regions -- because the light hits the polar regions at an angle

Answer 498

Minor chnage in solar intesnity can set a period where ice sheet advance in favorable

Answer 499

Both have to do with teh way the earth roattes on axis ***Speed is constant but the angle wibbles Precision = wobbles (20,000 year cycle) Ubiquity. =moves back and forth on title (41,000 year cycle)

Answer 500

Milakovicth cycles

Answer 501

1. Solar intensity 2. Fraction of incominhg radiation that is refected or abscobred 3. Composition of the atompshere

Answer 502

Reflective surfaces = have high Albedo = negitive feedback to warming VS. continenets and oceans are lower albedo --> melting. ifice sheets decreases the planet's albedo and is positive feedback to warming -- the uneven heating of eath from albedo variations between land or ice or ocean surfaces can drive weather patters

Answer 503

1. Cloud cover 2. Ice sheets -- more ice = more reflective vs. .less ice = more absorption of heat (more ice = have continued cooling vs less ive. =drives more warming because the non glacviated areas absorbes the heat) 3. Dust in the atmosphere from volcanic eruptions ***Things with high albedo = negitive feedback

Answer 504

Contients + oceans ***There is a lot of variation becasue of begitivation

Answer 505

Refect heat Example = ice sgeets

Answer 506

Absorb more radiations as heat rather than relecting Example -- contiennets + ocean

Answer 507

Melting if ice sheets + increasing the amopunt iof greenhosue gasses

Answer 508

The uneven heating of Earth from albedo variations between land, ice, or ocean surfaces can drive weather patterns

Answer 509

How much of earth is convered with ice = affects the albedo of earth --> ice. isrefective --> when light hits ice most of the light gets relfected back into space BUT if it hits areas that are not galciated then the light gets absobred as heat

Answer 510

Composition of atmpshere with resopect to greenhouse hasses that trao heat + the amount of dust in the atmosphete due to volacanic eruptions

Answer 511

More dust when volcanoe fist erupts = leads to cooler climates --> BUT CO2 and methans also are release -- after the dust settles the CO2 and methan stay and they increase the temperature by acting as greenhouse gasses

Answer 512

We do not think that the atompshere has chnaged in composition. in the last 800,000 years ***The thing that is chnaging the composition now is humans suing fossil fuels SINCE THERE IS LITTLE CHNAGE IN STOMPSHERE THE MILAKOVITCH CYLES SEEM TO HAVE BIG EFFECT

Answer 513

Because we know that the atompsjhere has not changed a lot = the milakovitch cyels affaect it a lot

Answer 514

We can tell the ice hseet size by the amount of O16 vs O18 in shells of specific organisms ***Proxy record is used to tell us how miuch water is trapped in ice sheets ***It is a proxy record because the hsells dont respond to the ice in the poled BUT the proportion of O in the sheels is a result of the amount of O16 being trapoped in the poles

Answer 515

The grapohs show a correlation between the chnage in O16 and O18 and the Milavovitch cyles

Answer 516

Because when ice sheets are bigger they trap more water --> they tend to trap the lighter isorope

Answer 517

O16 -- becayse the ice sheet is made out if snow and snow is made from evaportaion of the ocean --> the lighter isotope will evaportate fatser = it ends up in the snow more --> that oicean wtaer comes down as snow -- if the ice sheets are trapping more water they are trapping it fronm the snow (if the snow is made from higher O16 then the sheet will more readily trap O16)

Answer 518

O16 --> means that it ends up in the snow

Answer 519

The O16 in water will evaportae first --> means it will go into atsomeposhgere --> means that snow will have more )16 --> means the ice sheet will have more O16 + the oceans will have more O18

Answer 520

Means that there is higher O18 in the ocean THEN when the ice sheets melt they will put the O16 back into the ocean and will have more O16 in the ocean

Answer 521

We can see the variations in the Oxygen contained in calcite of marine shell animals (in the CaCO3)

Answer 522

Are. inequillibruim High O18 in water = High O18 in shells HIgh O16 in water = High O16 in shells

Answer 523

High O18 in the ocean

Answer 524

Lots of water trapped in ice sheets = higher O18 in wtare = higher O18 in shells Less water in ice sheets (ice sheets melt) = Higher O16 in wtaer = more O16 in hsells

Answer 525

Cylostritigraohy -- causes the ice sheets to shrink or grow

Answer 526

Effects can be seen in the seimentary rock record -- escoially for the recent geologic past we can identify some cylical trend in rock chemistry and charachyeristics thriugh time

Answer 527

Cause cylcial increases and decreases in the amount of freshwater that is stored in the polarice caops

Answer 528

Forminifera -- Oxygen isotope variations in. thefossils vary with the oxygen varaitions in the ocean -- BOTH the vraitions in Oxyegn in the ocean and the variation in O in the shells are responding to orgbital forcing by MC

Answer 529

Oxygen variations = occurs in response top Milakovitch cycles -- MC drives the Oxygen variations MC = vary solar intensity at the poles = affecsts the size of ice hseets = affect O in the ocean = affects shells

TEST #2 Flashcards

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