midterm 1 review Flashcards
manganese nodules are marine sediments that are
found on ocean bottoms far from shore, away from lithogenous sediments
at ________________, deep sea trenches are formed.
convergent plate boundaries
oxygen concentration is generally highest at
cold polar surface water.
sediments on the ocean floor are thickest ________________.
at the edge of ocean basins where oceanic crust is oldest
the concentration of each element in seawater is determined by
the rate of addition and the rate of removal.
the principle process whereby lithogenous sediments reach the middle of the ocean basins is transport by ___________.
winds
tectonic plates…
…are comprised entirely of continental and oceanic crust.
if the concentration of a gas in the surface layer of seawater is greater than the saturation solubility…
…there will be a net transfer of gas from water to atmos.
what are phytoplankton covered by small calcareous plates?
coccolithophores
the vast majority of lithogenous sediment transported by rivers to the oceans originates from
Asia
the relative abundance of different oxygen isotopes in glacial ice and fossils…because…
water molecules containing different oxygen isotopes evaporate at different rates
saturation solubility of gases in seawater increases with
increasing pressure and decreasing temp
CCD (carbonate compensation depth) depends on concentration of ________ in the water.
carbon dioxide
seawater is generally saturated with calcium carbonate from calcareous organisms only in __________.
shallow, warm water
most life on the deep seafloor sustains itself by
feeding on constant rain of detritus from above
hydrothermal water leaches metal sulfides easily from the oceanic crust because
has high CO2 concentration
large-grained sediments are transported down submarine canyons to abyssal plain by
turbidity currents
(2) major factors that determine accumulation rate of biogenous sediment are
rates of production, dissolution of biogenous particles
latent heat is…
heat used to change the phase of a substance but not its temp
lithospheric plates are
all of the above
new oceanic crust forms at ______ plate boundaries.
divergent
turbidity is a measure of
the transparency of the water to light, and the amount of suspended material in the water
from shoreline to deep seal floor, part of seafloor follow a sequence.
continental shelf, shelf break, continental slope, continental rise, abyssal plain
oceanic ridges are elevated above level of older deep seafloor as a result of
heat from the mantle that makes the crust hot and less dense
with increasing distance from an oceanic divergent margin (oceanic ridge) the lithosphere
increases in thickness
island + seamount chains formed by hotspot in the Pacific Ocean provide evidence that
tectonic plate has moved over the stationary hot spot
developing ocean modeling has a number of components. what are they?
sensitivity, parameterization, validation
the movements of lithospheric plates are thought to be driven primarily by
heat-driven convection in the mantle and gravity
the plate boundary between India and Asia is an example of a ______ margin.
convergent
naturally occurring organic compounds (carbon based) are introduced to seawater by
all of the above
seamounts near the middle of the oceans are mostly
extinct volcanoes originally formed at an oceanic ridge
for the ocean as a whole, the most abundant gas dissolved in seawater is
carbon dioxide
density of seawater is controlled primarily by
temperature and salinity
the oldest sediments on the ocean floor are found ____________.
near the edge of ocean basins and away from spreading centers
which of the following bonds is the strongest?
covalent bond
the high heat capacity of water allows it to
transport equatorial heat to high latitudes, moderate climate of coastal regions
the speed of sound in seawater
a, b, c, d
which of the following is true? (light of blue wavelengths)
a, b, c
the siliceous phytoplankton in zones of upwelling and around Antarctica are dominated by
diatoms
[t/f] biogeochemical cycles are thought to be at an approximate steady state.
true
[t/f] CCD is deeper in the Pacific than in the Atlantic
false
[t/f] the lithosphere can “flow” slowly over geologic time, much like the behavior of glass.
true
[t/f] age of islands in hotspot chains increases with distance from hotspot.
true
[t/f] water can dissolve more substances than any other known liquid.
true
[t/f] some of the largest volcanic eruptions go unnoticed because they occur at divergent plate boundaries.
true
[t/f] fine lithogenous sediment is continuously deposited on the ocean surface even far from the continents.
true
[t/f] the melting point temp of a substance increases as the van der Waals forces decreases.
false
[t/f] light of blue wavelengths is absorbed less effectively by seawater than light of red wavelengths.
true
[t/f] earth’s core is composed primarily of iron and lead.
false
[t/f] sound velocity in seawater increases with increasing temps.
true
[t/f] deep seafloor marine sediments typically have a high organic content from the accumulation of detritus.
false
[t/f] the pH of a solution is a measure of the hydroxide ion concentration in the solution.
true
[t/f] manganese nodules grow quickly in areas with high sedimentation rates.
false
[t/f] covalent compounds are generally more soluble in water than ionic compounds.
false
[t/f] it takes more heat to evaporate a gram of water from a rain puddle that it does to produce a gram of water vapor from water that is at its boiling point.
true
[t/f] phosphorite nodules grow near zones of upwelling along continental margins.
true
[t/f] the latent heat of fusion of ice is greater than the latent heat of evaporation of water.
false
[t/f] ttl. quantity of water in earth’s oceans, lakes, rivers, and ice caps has remained fairly constant for millions of years.
true
