Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
88 Cards in this Set
- Front
- Back
What is the term for the area from low tide to the highest level on land affected by storm waves?
|
Shoreline
|
|
T or F
Shorelines continuously adjust to changes such as increased or diminished sediment supply or wave activity. |
TRUE
|
|
What migrates with sea level changes?
|
Shorelines
|
|
What term includes:
Shoreline Nearshore sandbars and islands Sand dunes Marshes Sea cliffs? |
Coast
|
|
What is the term for regular fluctuations of the sea in response to the gravitational attraction of the moon and sun?
|
Tides
|
|
How many cycles of tides are there usually per day?
|
Usually 2 cycles of tides per day
|
|
How many days revolution does the Moon have?
|
28 days
|
|
How many times smaller is the Moon?
|
27 million times smaller
|
|
What percentage stronger is the Moon's gravitational pull?
|
46%
|
|
What type of tide results from sun and moon combined?
|
Spring tide
|
|
What type of tide averages 20% higher on average?
|
Spring
|
|
What type of tide results from sun and moon at right angles?
|
Neap tide
|
|
What type of tide averages 20% lower tides on average
|
Neap tides
|
|
What is the term for oscillations of the water surface which transmit energy, in the direction of its movement?
|
Wave
|
|
What is the term for the highest point of a wave?
|
Crest
|
|
What is the term for the lowest point of a wave?
|
Trough
|
|
What is the term for the distance from crest to crest between waves?
|
Wavelength
|
|
What is the term for the distance from trough to crest of a wave?
|
Wave height
|
|
What is the term for the time it takes for successive crests of waves to pass a given point?
|
Period (T)
|
|
What does L/2 mean?
|
Wave base
|
|
How is wave speed determined?
|
Wavelength (L)
_______________ Period (T) |
|
Name the 4 causes that create waves:
|
1. Wind
2. Landslides 3. Faultings 4. Volcanic eruptions |
|
How does wind create waves?
|
Fuid air over fluid water causes friction/transfer of energy causing water to oscillate
|
|
Name the 3 controlling factors of waves?
|
1. Wind velocity
2. Wind duration 3. Fetch |
|
What is the term for the distance the wind blows over a continuous water surface?
|
Fetch
|
|
What happens to wavelength and wave height as waves enter water shallower than the wave base?
|
Wavelength decreases
Wave height increases |
|
What is the result of waves that enter water shallower than the waves?
|
Waves become oversteepened and plunge forward as breakers
|
|
What is the term for the area extending seaward from the upper limit of the shoreline to just beyond where the waves break?
|
Nearshore
|
|
What 2 zones are included in the nearshore?
|
1. Breaker zone
2. Surf zone |
|
What 2 types of waves are included as incoming waves?
|
1. Longshore waves
2. Rip currents |
|
What is the term for the bending of waves so that they more nearly parallel the shoreline?
|
Wave refraction
|
|
What is the term for current resulting from wave refraction that flows parallel to the shoreline?
|
Longshore currents
|
|
What is responsible for much transport and deposition?
|
Longshore currents
|
|
What is the term for narrow, surface currents which rapidly carry water from the nearshore zone seaward through the breaker zone?
|
Rip currents
|
|
What type of water movements are extremely dangerous to swimmers?
|
Rip currents
|
|
What type of surface feature develops where erosion exceeds deposition in relation to the sea?
|
Sea cliffs
|
|
What is the term for the surface feature that is formed as a gently sloping, beveled surface abraded by wave action?
|
Wave-cut platforms
|
|
What is the term for the surface feature that are wave-cut platforms that have been raised above sea level?
|
Marine terraces
|
|
Wave erosion causes a sea cliff to migrate in what direction?
|
Landward
|
|
What is the term for the gently sloping surface along the coast of California?
|
Marine terrace
|
|
What is the term for the seaward-projecting parts of the shoreline?
|
Headlands
|
|
What might be formed by the wave refraction around rocky headland?
|
Sea caves
|
|
With continued erosion, what can sea caves merge to form?
|
Sea arches
|
|
With continued erosion, what does a collapsed arch leave?
|
Sea stacks
|
|
What is the term for deposits of unsonsolidated sediment extending landward from low tide to the edge of the dunes or a sea cliff?
|
Beaches
|
|
What is considered to be the most common shoreline depositional feature?
|
Beaches
|
|
What surface feature are continually modified by the action of waves, longshore currents, tides and storms?
|
Beaches
|
|
What surface features may be continuous or isolated pocket?
|
Beaches
|
|
What types of beaches are there?
|
1. Continuous
2. Isolated pocket |
|
What are the 4 component to a beach?
|
1. Backshore
2. Berms 3. Beach face 4. Forehsore |
|
Which beach component is usually dry?
|
Backshore
|
|
Which beach component are platforms that slope gently landward?
|
Berms
|
|
Which beach component is exposed to the wave swash?
|
Beach face
|
|
Which beach component is covered by water in high tide?
|
Foreshore
|
|
What is the term for water that washes up on shore?
|
Swash
|
|
What is the term for wter that roll back down the beach after wave break?
|
Backwash
|
|
T or F
Beach configuration remains unchanged under equilibrium conditions. |
TRUE
|
|
Seasonal changes to beach configuration are related to wate?
|
Wave intensity
|
|
T or F
Longshore currents modify beach configuration to a lesser extent. |
TRUE
|
|
T or F
Summer beaches are coarser grained, have a wide berm and gently sloping beach face. |
TRUE
|
|
How is most beach sediment transported to the beach?
|
By streams
|
|
In what type of pattern do longshore currents move grains?
|
Zig-zag pattern
|
|
What is the term for structures projecting seawards at right angles to the shoreline?
|
Groins
|
|
Whartare often built to widen a beach or slow erosion?
|
Groins
|
|
What is the term for fingerlike projection of a beach into a body of water such as a bay?
|
Spits
|
|
Describe the ends of recurved spits?
|
Curved free ends
|
|
What is the term for a spit that has grown until it completely closes off a bay from the open sea?
|
Baymouth Bars
|
|
What physical features can both be problematic where bays need to be kept open?
|
1. Spits
2. Baymouth bars |
|
What is the term for a type of spit extending out from the shoreline to an island?
|
Tombolo
|
|
What forms on the shoreward side of an island by refracted waves?
|
Tombolo
|
|
What cause the formation and growth of spits, baymouth bars and tombolos?
|
Longshore currents
|
|
What is the term for long narrow islands of sand formed at short distance offshore?
|
Barrier islands
|
|
Describe the beach side of a barrier island?
|
Smoothed by waves
|
|
Describe the landside of a barrier island?
|
Irregular due to storm shower deposits
|
|
What are physical features of barrier islands?
|
1. beaches
2. wind-blown dunes 3. marshy areas |
|
What is the term for the balance of sediment inputs and sediment losses in a shoreline system?
|
Nearshore Sediment Budget
|
|
What is the source for most sediment input?
|
Streams and rivers transporting sediment to the shore
|
|
How is sediment lost along a shore?
|
1. Longshore drift
2. Longshore wind 3. Offshore sediment transport |
|
What are the characteristics of depositional coasts?
|
1. abundant sediment
2. wide sandy beaches 3. deltas 4. barrier islands |
|
What are the characteristics of erosional coasts?
|
1. steep irregularity
2. lack well developed beaches |
|
Where are many erosional coasts in the US?
|
West coast US beaches
|
|
What is the term for coasts where sea level is rising with respect to land?
|
Submergent coasts
|
|
What is the term for coasts where land has risen with respect ot sea level?
|
Emergent coasts
|
|
What causes emergent coasts?
|
1. tectonics
2. isostacy |
|
List the risks of living near shorelines?
|
1. mass wasting
2. beach loss due to erosion/deposition 3. storm damage 4. economic impact |
|
List control techniques for living along shorelines:
|
1. sand replenishment
2. seawalls-reinforce concrete 3. riprap 4. groins |
|
What is the term for reinforced concrete used to control shorelines?
|
Seawalls
|
|
What is the term for piles of stones used to control shorelines/
|
Riprap
|