Coasts Flashcards
what is the littoral zone
the littoral zone is the sub zones of the beach/coast
name the littoral zones
foreshore , backshore , offshore and nearshore
what state is the littoral zone in
dynamic equilibrium
what is both a key input AND output of the littoral system
sediment
name the inputs into the littoral system
sediment , wind , the action of waves and currents
what are the two type of energy coastlines
high energy and low energy
what type of wave would be at a high energy coastline
destructive waves
what is unique about high energy coastlines
long fetches & high rates of erosion
what erosional landforms form at high energy coastlines
wave cut platforms , caves , arches , stacks and stumps and cliffs
what type of wave occurs at a low energy coastline
constructive waves
what is unique about low energy coastlines
shorter fetches & higher rates of deposition
what landforms form at low energy coastlines
spits and bars , tombolas , salt marshes ,sand dunes & beaches
what is the formation of a concordant coastline
alternating bands of hard and soft rock run parallel to the coastline
what is the formation of a discordant coastline
alternating hard and soft rock run 90 degrees to the coastline
which coastline are erosional landforms more likely to be found
discordant
what is an example of a discordant coastline
dorset coastline
what are the two rock types at dorests coastline
portland limestone and greensands
what are concordant coasts also known as
pacific coastlines
what do pacific coastlines led to the formation of
dalmatian coastlines
what is a dalmation coastline
a coastline made up of offshore islands and coastal inlets running parallel to the coast
name an example of a dalmation coast
lulworth cove
what are discordant coastlines also known as
atlantic coastlines
what landforms often form at discordant coastlines
headlands and bays
what’s an example of an area of headlands and bays
swanage bay
what is a dip
the angle the rock layer forms with the horizontal bedding plane
how is faulting and folding formed
through the deformation and stress from tectonic processes
which way can dips form
towards the sea or towards the land
if a dip is towards the sea what type of cliff profile will it have
gentle
if a dip is towards land what type of cliff profile will it have
steep
what is the angle of the dip known as
the joint
why would a rock with more joints and faults be more susceptible to erosion
as they have more weak spots that can be broken down and eroded away through erosion or weathering
what is bedrock lithology
the discussion of the different properties of a rock
what are the three types of rocks
sedimentary , igneous and metamorphic
how are sedimentary rocks formed
through the layers of sand and material compacting overtime through lithification
how are igneous rocks formed
through the crystallization of magma
how are metamorphic rocks formed
through the change in structure of sedimentary and igneous rocks
what is the process called when rocks become metamorphic rocks
metamorphosed
name two types of sedimentary rock
limestone and sandstone
name two types of igneous rock
basalt and granite
name two types of metamorphic rock
slate and marble
which two rock types are more resistant to erosion
igneous and metamorphic
what is the erosion rate of igneous rock each year
0.1 - 0.5 cm a year
what is the erosion rate of sedimentary rock each year
2 - 6 cm
where does the sand dune transect go from
the mobile dunes (embryo and yellow dunes) to the fixed dunes (gray and dune slack)
how many types of plants are within sand dunes
two
what are the two types of vegetation within sand dunes called
xerophytes and halophytes
what are the properties of xerophytes
can withstand periods of dry weather
what are the properties of halophytes
plants that can withstand high levels of salt concentration from seawater
at a high energy coastline _____ outweighs _____
erosion outweighs deposition
at a low energy coastline _______ outweighs ______
deposition outweighs erosion
shape and form of coastal landscapes
coastal morphology
vertical cracks , fractures caused by contraction as sediment drys out
joints
horizontal cracks or natural breaks in the strata caused by gaps in time periods of sediment formations
bedding planes
the layers within rocks
strata
different characteristics of rock
lithology
the angle at which the rock strata lies
dip
these are formed when the stress or pressure to rock is subjected to the coast
faults
name the outputs of the coastal system
depositional landforms , erosional landforms and different types of coasts
name the inputs of the coastal system
-people (human activity and coastal management)
-land (rock type , structure, tectonic activity)
-marine (waves , tides , storm surges) -atmosphere (weather, climate and climate change , solar energy)
name the processes of the coastal system
weathering , mass movement , deposition , transport and erosion
how are waves mostly formed
by wind blowing over water
if the wind is at a greater speed what will the wave be like
larger
what does wind create
fictional drag which produces movement in the upper surface of the water
what is a swell wave and how is it formed?
swell waves are waves formed in the middle of the ocean by storms over the open ocean
what is the fetch
the distance a wave travels
the distance between two different waves crests
wavelength
the highest point of the wave
the crest
the lowest point of the wave
trough
the distance between a waves trough and crest
waveheight
what are the two orbits in the wave cycle
circular orbit and elliptical orbit
when would a wave have a circular orbit?
when it is first forming
when would a wave have an eliptical orbit
when it is about to hit the beach
when the water from a wave retreats back into the sea
backwash
when the wave washes up on the shoreline
swash
