Coastal Hazards - Shorelines Flashcards
strip of land bordering the sea or ocean along a continent or an island
coast/shore
marks the seaward limit of the landmass,
which is permanently exposed to wave action.
coastline/shoreline
chief agents shaping coastlines
waves, currents, tides, and winds
t or f: some coasts are straight while others are rugged
t
t or f: some coasts contain marshes or coral reefs
t
marks the boundary between the sea and land
shoreline
zone affected by wave action
shore
this part of the shore is nearest to the sea. It is under
water even at low tide.
offshore
between the low tide breaker line and the low tide
shoreline
nearshore
this refers to the zone between high tide and low
tide. It is under water during high tide. It is the surf zone.
foreshore
this is also known as the surf zone
foreshore
t or f: the foreshore is underwater during high tide
t
it is the part of the shore between the high tide and
the highest water level, which can only be reached by
exceptional storm waves
backshore
backshore’s sea bed is strewn with ______ and ________
shingle and pebbles
draw the parts of a coastline
are areas where tectonic forces deform
and uplift the land. They are
usually rugged and irregular,
with beaches sometimes being
restricted to coves and inlets
active shorelines
beaches of active shorelines are sometimes being restricted to ________ and ______
coves and inlets
examples of active shorelines
Pacific Coast of US
Eastern Coast of Philippines fronting the Ph trench
are areas with little to no tectonic activity,
commonly resulting in a
relatively straight coastline with
flat lying terrain
passive shorelines
examples of passive shoreline
U S Gulf
Atlantic Coasts
are mass wasting hazards would be more prevalent along tectonically active or passive shorelines?
tectonically active shorelines
_______ terrain of ________ is conducive to high density development
low-lying ; passive coastlines
are the outer margins of the continents, where continental crust transitions to oceanic crust
continental margin
continental margins can be classified as either:
active or passive
are geologically inactive regions located some distance from plate boundaries
passive continental margins
t or f: passive continental margins are relatively wide and have large quantities of sediments deposited
t
passive continental margins comprises features such as:
continental shelf, slope, and rise
this type of margin is located along convergent plate boundaries, where oceanic lithosphere is being subducted beneath the leading edge of a continent
active continental margin
average slope of continental shelf
1/10th of 1 degree
average slope of continental slope
approx. 5 degrees
these develop along subduction zones where sediments from the ocean floor are scraped from the descending oceanic plate and pressed against the edge of the overriding plate
accretionary wedges
occurs when sediment and rock scraped off the bottom of the overriding plate is carried into the mantle by the subducting plate
subduction erosion
Another important process
that affects the nature of
shorelines is the relative
movement of the shoreline
either _________ or _______
seaward or landward
Shorelines also shift in
response to _____________ that occur
when Earth’s global climate
alternates between cool,
glacial periods and warm
periods called interglacials
worldwide changes in sea level
a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age
interglacial period
sea level today is rising at the rate of
0.6 feet (0.2m) per century
sea level rise could change drastically should global warming destabilize ice sheets on _______ and ______
Greenland and Antartica
