UCSB Intro to Oceanography Final Exam
Questions with Correct Answers 2026
p-waves - correct answer -compression/longitudinal waves created by earthquakes capable of
traveling through liquids and solids (earths core)
S-waves - correct answer -transverse waves created by earthquakes that are not able to travel
through liquids and thus bend around earths liquid outer core
Lithosphere - correct answer -rigid outer layer of earth ~100km thick, composed of continental
and oceanic crust
Continental crust - correct answer -thick and the least dense, composed of granitic rock
Oceanic crust - correct answer -thinner and denser than continental crust, composed of basaltic
rock
Mantle - correct answer -earths middle layer, composed of silicate materials, iron, magnesium,
and oxygen. Divided into asthenosphere and mesosphere
Asthenosphere - correct answer -"plastic" upper layer of mantle, high viscosity flow ~100-700
km down
Mesosphere - correct answer -mid/lower mantle, semi-rigid due to high pressure ~700-2885 km
down
Outer core - correct answer -earths liquid outer core
,Inner core - correct answer -earths solid iron core
Density stratification - correct answer -early earth likely homogeneous and hot, after cooling
denser layers move towards gravitational pull of center
Isostatic adjustment - correct answer -buoyancy, how less dense crust layers "float" on fluid
asthenosphere
Wegener's hypothesis - correct answer -alfred wegener- hypothesis of continental drift: less
dense crust floats on plastic asthenosphere. This fit pangea hypothesis, matching shorelines,
fossil record/coal deposit/glacial erosion similarities. No motion mechanism
Seafloor spreading hypothesis - correct answer -hess and dietz (1960): new crust formed at mid-
ocean ridges and spreads. Driven by convection current in underlying mantle
Plate tectonic theory - correct answer -combination of seafloor spreading and continental drift:
plates float on plastic asthenosphere driven by mantle convection currents. 7 major lithospheric
plates
Evidence for plate tectonics - correct answer -seismographs plot volcanic and seismic activity at
plate boundaries, echo sounders show mid-ocean ridges on seafloor, radiometric dating shows
ocean crust is much younger than continental (~200 my v ~4 by)
Where does internal heat driving mantle convection come from? - correct answer -radioactive
decay
Paleomagnetism - correct answer -past shifts in earths magnetic poles that produce alternating
stripes in new ocean crust.
, Magnetite - correct answer -iron particles that align themselves with earths magnetic poles
Hot spots - correct answer -surface expression of magma plumes, new crust or island chains are
formed as oceanic crust moves over them
Divergent boundary - correct answer -plates moving away from each other, typically associated
with mid-ocean ridges or continental rifting
Continent-continent convergent plate boundary - correct answer -two continental plates collide,
earth pushes upwards to form mountains (himalayas)
Ocean-continent convergent plate boundary - correct answer -denser oceanic crust subducts
under continental crust, creates oceanic trench and volcanic activity underneath continent
(west coast of south america)
Ocean-ocean convergent plate boundary - correct answer -older, denser oceanic crust subducts
creating trench and typically volcanic island chain
Transform plate boundary (strike-slip) - correct answer -two plates slide parallel to each other,
crust not created or destroyed (san andreas fault), can also occur between offsets of spreading
ridges
Pacific ring of fire - correct answer -ring of high volcanic and seismic activity around the pacific
ocean
Continental accretion - correct answer -continents add landmass when small pieces of land
accumulate on edges
Questions with Correct Answers 2026
p-waves - correct answer -compression/longitudinal waves created by earthquakes capable of
traveling through liquids and solids (earths core)
S-waves - correct answer -transverse waves created by earthquakes that are not able to travel
through liquids and thus bend around earths liquid outer core
Lithosphere - correct answer -rigid outer layer of earth ~100km thick, composed of continental
and oceanic crust
Continental crust - correct answer -thick and the least dense, composed of granitic rock
Oceanic crust - correct answer -thinner and denser than continental crust, composed of basaltic
rock
Mantle - correct answer -earths middle layer, composed of silicate materials, iron, magnesium,
and oxygen. Divided into asthenosphere and mesosphere
Asthenosphere - correct answer -"plastic" upper layer of mantle, high viscosity flow ~100-700
km down
Mesosphere - correct answer -mid/lower mantle, semi-rigid due to high pressure ~700-2885 km
down
Outer core - correct answer -earths liquid outer core
,Inner core - correct answer -earths solid iron core
Density stratification - correct answer -early earth likely homogeneous and hot, after cooling
denser layers move towards gravitational pull of center
Isostatic adjustment - correct answer -buoyancy, how less dense crust layers "float" on fluid
asthenosphere
Wegener's hypothesis - correct answer -alfred wegener- hypothesis of continental drift: less
dense crust floats on plastic asthenosphere. This fit pangea hypothesis, matching shorelines,
fossil record/coal deposit/glacial erosion similarities. No motion mechanism
Seafloor spreading hypothesis - correct answer -hess and dietz (1960): new crust formed at mid-
ocean ridges and spreads. Driven by convection current in underlying mantle
Plate tectonic theory - correct answer -combination of seafloor spreading and continental drift:
plates float on plastic asthenosphere driven by mantle convection currents. 7 major lithospheric
plates
Evidence for plate tectonics - correct answer -seismographs plot volcanic and seismic activity at
plate boundaries, echo sounders show mid-ocean ridges on seafloor, radiometric dating shows
ocean crust is much younger than continental (~200 my v ~4 by)
Where does internal heat driving mantle convection come from? - correct answer -radioactive
decay
Paleomagnetism - correct answer -past shifts in earths magnetic poles that produce alternating
stripes in new ocean crust.
, Magnetite - correct answer -iron particles that align themselves with earths magnetic poles
Hot spots - correct answer -surface expression of magma plumes, new crust or island chains are
formed as oceanic crust moves over them
Divergent boundary - correct answer -plates moving away from each other, typically associated
with mid-ocean ridges or continental rifting
Continent-continent convergent plate boundary - correct answer -two continental plates collide,
earth pushes upwards to form mountains (himalayas)
Ocean-continent convergent plate boundary - correct answer -denser oceanic crust subducts
under continental crust, creates oceanic trench and volcanic activity underneath continent
(west coast of south america)
Ocean-ocean convergent plate boundary - correct answer -older, denser oceanic crust subducts
creating trench and typically volcanic island chain
Transform plate boundary (strike-slip) - correct answer -two plates slide parallel to each other,
crust not created or destroyed (san andreas fault), can also occur between offsets of spreading
ridges
Pacific ring of fire - correct answer -ring of high volcanic and seismic activity around the pacific
ocean
Continental accretion - correct answer -continents add landmass when small pieces of land
accumulate on edges
