MARINE EXAM 1 QUESTIONS & ANSWERS
Define these terms: divergent boundary, convergent boundary, transform boundary
trailing margin and give examples of where each occur along the US coast line -
Answers :Divergent Boundary - A tectonic plate boundary where two plates are moving
away from one another Example: North part of West Coast, lots of examples around
South America too Convergent Boundary - A tectonic plate boundary where two plates
are moving closer to one another and one will eventually GO UNDER the other
Example: Part of the West Coast Transform Boundary - A tectonic plate boundary
where two plates are 'slipping' against each other sideways Example: California Trailing
Margin - A coastline which is not on a tectonic plate boundary and is moving away from
one Example: US East Coast
Explain how boundary type affects shelf width. - Answers :Places on a convergent will
have a very narrow shelf because there's a boundary right there so it has to stop
abruptly, places on a trailing margin will have a very wide shelf since they have lots of
room.
Define the term isostatic adjustment. - Answers :Adjustment of the Earth's mantle as a
result of erosion from land which results in the mantle sinking and the land being lifted
upwards.
Using isostasy, explain what happens to a shelf on a trailing margin as eroded material
is added. - Answers :The shelf gets heavier and heavier and sinks until eventually a
canyon is formed where all the excess material drops off into.
Define the terms tropical and temperate in terms of latitude. - Answers :Temperate:
23.5° to the polar circles at about 66.5°, north and south Tropical: Latitudes between
23.55 and 23.5 N
Give examples of 4 typical ecosystems on a trailing margin. - Answers :Sandy Beaches,
Salt Marshes, Mangals, Drowned River Valleys
Describe shoreline-erosion distribution along US coasts and how it is related to
shoreline type. Include the east coast, the west coast, the Gulf of Mexico and Alaska. -
Answers :East Coast: Trailing margin, heavily eroding West Coast: Convergent margin
→ rising, moderately eroding with sea surface level rise Gulf of Mexico: Severely
eroding Alaska: Severely eroding
As an estimate, how much shoreline erosion would be caused by a 1-inch sea level
increase? - Answers :100 inches of land will erode
Define the term geological hotspot and give examples of coastal US areas formed by
hotspots. - Answers :The places known as hotspots or hot spots are volcanic regions
thought to be fed by underlying mantle that is anomalously hot compared with the
, surrounding mantle. Their position on the Earth's surface is independent of tectonic
plate boundaries. Yellowstone and the US West Coast have been largely formed by
geological hotspots.
What three things determine wave size? - Answers :Wind speed Wind duration Fetch
(The distance where the wind blows in a straight path) The higher these are, the higher
the waves are
In which direction do hurricanes rotate in the northern hemisphere? - Answers :Counter
clockwise
Describe formation of longshore transport. What does the longshore transport carry? -
Answers :Waves come in at an angle and get pushed back straight, over time they
move farther and farther down the shore and carry sediment from rivers (usually)
Define the following terms (Diurnal tide, Semidiurnal tide, Semidiurnal mixed tide, high
tide, low tide): - Answers :Diurnal tide - Only one tide and one low tide per day
Semidiurnal tide - Two high tides and two low tides per day Semidiurnal mixed tide -
Two high tides and two low tides of different sizes High tide - The point at which velocity
is 0 and starts going out Low tide - The point at which velocity is 0 and starts coming in
What is the most common tide type globally? - Answers :Semidiurnal
How does the Coriolis effect affect large-scale movement in the Northern versus
Southern hemisphere? - Answers :In the Northern Hemisphere, large scale movement
rotates counter clockwise. In the Southern Hemisphere, it rotates clockwise.
Explain how airpressure causes deviations from predicted tidal height. - Answers :When
air pressure is increased, tides will be lower than expected as the air pushes down on
the water's surface.
Explain the difference between high tide and flooding tide. - Answers :High tide is the
specific point at which the tide reaches its highest point, flooding tide is the range of
time in which the tide is coming in.
Explain the difference between low tide and ebbing tide. - Answers :Low tide is the
specific point at which the tide reaches its lowest point, ebbing tide is the range of time
in which the tide is going out.
Describe how a trophic pyramid differs from a food web. Which is more realistic? -
Answers :A trophic pyramid features a number of species in each level and shows
transfer of energy, a food web shows who eats who. A trophic pyramid is thus more
realistic as it is more generalized.
Which compounds are consumed in primary production? Which are produced? -
Answers :Consumes CO2 and water, Produces oxygen and glucose
Define these terms: divergent boundary, convergent boundary, transform boundary
trailing margin and give examples of where each occur along the US coast line -
Answers :Divergent Boundary - A tectonic plate boundary where two plates are moving
away from one another Example: North part of West Coast, lots of examples around
South America too Convergent Boundary - A tectonic plate boundary where two plates
are moving closer to one another and one will eventually GO UNDER the other
Example: Part of the West Coast Transform Boundary - A tectonic plate boundary
where two plates are 'slipping' against each other sideways Example: California Trailing
Margin - A coastline which is not on a tectonic plate boundary and is moving away from
one Example: US East Coast
Explain how boundary type affects shelf width. - Answers :Places on a convergent will
have a very narrow shelf because there's a boundary right there so it has to stop
abruptly, places on a trailing margin will have a very wide shelf since they have lots of
room.
Define the term isostatic adjustment. - Answers :Adjustment of the Earth's mantle as a
result of erosion from land which results in the mantle sinking and the land being lifted
upwards.
Using isostasy, explain what happens to a shelf on a trailing margin as eroded material
is added. - Answers :The shelf gets heavier and heavier and sinks until eventually a
canyon is formed where all the excess material drops off into.
Define the terms tropical and temperate in terms of latitude. - Answers :Temperate:
23.5° to the polar circles at about 66.5°, north and south Tropical: Latitudes between
23.55 and 23.5 N
Give examples of 4 typical ecosystems on a trailing margin. - Answers :Sandy Beaches,
Salt Marshes, Mangals, Drowned River Valleys
Describe shoreline-erosion distribution along US coasts and how it is related to
shoreline type. Include the east coast, the west coast, the Gulf of Mexico and Alaska. -
Answers :East Coast: Trailing margin, heavily eroding West Coast: Convergent margin
→ rising, moderately eroding with sea surface level rise Gulf of Mexico: Severely
eroding Alaska: Severely eroding
As an estimate, how much shoreline erosion would be caused by a 1-inch sea level
increase? - Answers :100 inches of land will erode
Define the term geological hotspot and give examples of coastal US areas formed by
hotspots. - Answers :The places known as hotspots or hot spots are volcanic regions
thought to be fed by underlying mantle that is anomalously hot compared with the
, surrounding mantle. Their position on the Earth's surface is independent of tectonic
plate boundaries. Yellowstone and the US West Coast have been largely formed by
geological hotspots.
What three things determine wave size? - Answers :Wind speed Wind duration Fetch
(The distance where the wind blows in a straight path) The higher these are, the higher
the waves are
In which direction do hurricanes rotate in the northern hemisphere? - Answers :Counter
clockwise
Describe formation of longshore transport. What does the longshore transport carry? -
Answers :Waves come in at an angle and get pushed back straight, over time they
move farther and farther down the shore and carry sediment from rivers (usually)
Define the following terms (Diurnal tide, Semidiurnal tide, Semidiurnal mixed tide, high
tide, low tide): - Answers :Diurnal tide - Only one tide and one low tide per day
Semidiurnal tide - Two high tides and two low tides per day Semidiurnal mixed tide -
Two high tides and two low tides of different sizes High tide - The point at which velocity
is 0 and starts going out Low tide - The point at which velocity is 0 and starts coming in
What is the most common tide type globally? - Answers :Semidiurnal
How does the Coriolis effect affect large-scale movement in the Northern versus
Southern hemisphere? - Answers :In the Northern Hemisphere, large scale movement
rotates counter clockwise. In the Southern Hemisphere, it rotates clockwise.
Explain how airpressure causes deviations from predicted tidal height. - Answers :When
air pressure is increased, tides will be lower than expected as the air pushes down on
the water's surface.
Explain the difference between high tide and flooding tide. - Answers :High tide is the
specific point at which the tide reaches its highest point, flooding tide is the range of
time in which the tide is coming in.
Explain the difference between low tide and ebbing tide. - Answers :Low tide is the
specific point at which the tide reaches its lowest point, ebbing tide is the range of time
in which the tide is going out.
Describe how a trophic pyramid differs from a food web. Which is more realistic? -
Answers :A trophic pyramid features a number of species in each level and shows
transfer of energy, a food web shows who eats who. A trophic pyramid is thus more
realistic as it is more generalized.
Which compounds are consumed in primary production? Which are produced? -
Answers :Consumes CO2 and water, Produces oxygen and glucose