Oceanography Exam One
How long does it take for the Earth to make one rotation on its axis?
24 hours
If a clock is set to Greenwich Mean Time and the sun is observed to reach its zenith at 10:00 AM, what is the longitude?
30 degrees E
What minimum percent must be exceeded for a deep-sea biogenic ooze to be named after its principal component?
30%
The maximum penetration of visible light in clear seawater is about _____ meters.
300
How long does it take for Earth to make one revolution around the sun?
365 days
The average depth of the ocean is about ______.
3800m
Earth is the _____ planet from the sun.
3rd
How many hours must be added to New York City's Eastern daylight time to obtain Greenwich Mean Time or Universal Time?
4
Fresh water has its maximum density at ______.
4 degrees C
Earth's age is estimated at ______ years.
4.6x10^9
If a sound pulse is sent vertically downward into the sea and its reflected echo from the seafloor returns 6 seconds later, the depth of the water is _____ meters. (The average speed of sound in seawater is 1500m/sec.)
4500
Which ocean basin is the largest?
Pacific
Which layer is believed to behave most like a liquid?
outer core
An error in time of two minutes in determining longitude from local time and Greenwich Mean Time will cause a _____ error in longitude.
0.50 degree
Earth turns on its axis about ______.
1 degree in 4 minutes
Seafloor spreading is continuing at a rate of approximately _________.
1 to 10 cm/year
The pressure increase experienced by equipment lowered to a depth of 1000m is approximately ________.
100 atmospheres
The Big Bang occurred roughly _____ years ago.
13 billion
A time zone is approximately _____ degrees wide.
15
The mean surface temperature of Earth is about ______.
16 degrees C
During the next magnetic reversal, the magnetic force field surrounding Earth will shift by about ______.
180 degrees
The present oceans have been created during the last _______.
225 million years
The Arctic and Antarctic circles are displaced _____ degrees from their respective poles.
23 1/2
During the Northern Hemisphere's summer solstice, the sun stands above _____.
23 1/2 degrees N
The Tropic of Capricorn is at ______ latitude.
23 1/2 degrees S
Major deposits of silicous oozes from the radiolaria are found centered on which latitudes?
5 degrees N
Roughly what percentage of matter in the universe is the type of matter that composes the planets and stars?
5%
The mean radius of Earth is _____ meters.
6.37x10^6
One degree of latitude is about equal to _____.
60 nautical miles
If a clock set to Greenwich Mean Time or Universal Time is moved to a location where Noon, according to the sun, occurs at 4:30 PM clock time, what is the longitude of the clock?
67.5 degrees W
Approximately what percentage of gas emitted by volcanoes is water vapor?
70%
Water covers _____ % of Earth's surface.
71
Which circle of latitude or longitude has the smallest circumference?
80 degrees S
Approximately what percentage of water on Earth is contained within the oceans?
97%
The theory of drifting continents was proposed by _________.
Alfred Wegener
Where do earthquakes occur?
All boundaries (convergent, divergent, and transform)
The South Pole is tilted toward the sun on what day?
December solstice
Identify all of the types of plate boundaries that are associated with active volcanism.
Divergent and convergent
Which of the following factors(s) enable(s) the existence of liquid water on the Earth's surface?
Earth's solar orbit, rotation of the Earth on its axis, and the Earth's atmospheric gases
Which of the following help us believe that Earth's mass is distributed spherically and uniformly around Earth's center?
Earth's spherical shape and lack of rotational wobble
_______ is a measure of the total kinetic energy of the atoms and molecules in a substance.
Heat
Relationships between oceanic depths or land elevations and Earth's area are shown on a _______.
Hypsographic curve
Which ocean basin is located primarily in the Southern Hemisphere?
Indian
The east coast of the US is an example of a(n) _______ continental margin.
Passive and trailing
A program of deep-sea drilling for cores from the ocean's bottom is carried out by the ______.
JOIDES Resolution
Identify all of the planets that are rich in ices of water, ammonia, and methane.
Jupiter, Saturn, Uranus, and Neptune
The deepest depth of the oceans is located in which trench?
Mariana Trench
Identify all of the planets that are rich in metals and rocky materials.
Mercury, Venus, Earth, and Mars
Why are plate boundaries, both present and ancient, of interest to resource economists?
Metallic ore deposits are found in these locations
Which ocean basin is the deepest on average?
Pacific
Identify all of the different observations Alfred Wegener used to support his theory of continental drift.
The geographic fit of the continents, fossils of plants and animals, mountain ranges of similar age, structure, and rock composition, unusual sequences of rocks and rock units of similar age and chemistry, and patterns of glaciation
Why are meteorites used to establish an age for the Earth?
They are believed to be the same material from which Earth formed, rocks on Earth have been recycled since the Earth was formed and are not believed to be as old as the Earth itself
Which of the following is NOT true about passive continental margins?
They are commonly at subduction zones
At what latitude is the sun directly overhead on the June Solstice?
Tropic of Cancer
The floor of a major ocean basin is called a(n) ________.
abyssal plain
Viscosity of ocean water increases primarily _____.
as temperature decreases
Surface coral formations growing around completely submerged seamounts are called ______.
atolls
The long red wavelengths of visible light are ______.
attenuated very rapidly
The motion between the two sides of a transform fault is greatest __________.
between the adjacent ridge axes
The ______ wavelengths of light penetrate deepest into the ocean.
blue
Heat is measure in ______.
calories
Seafloor spreading can be detected by _______.
changes in water temp, changes in water chemistry, sound monitoring, and submarine observation of the seafloor
Which substance has the greatest density?
cold salt water
The 1977 and 1979 expeditions with the ALVIN and the Galapagos Rift _________.
collected large animals from vent communities
Which method best transmits heat through water?
convection
Water heated from below distributes the added heat by _____, whereas the still surface of water heated from above distributes the added heat by _______.
convection; diffusion and conduction
Which of the following is least likely to be a major component of marine sediments?
cosmogenous materials
The polarity of water molecules is responsible for all of the following, except:
covalent bonding
The Moho is located between the ________.
crust and mantle
The particle size of terrigenous sediments generally _____ with distance from shore.
decreases
Lithogenous sediment is _______.
derived fromrock
The US Global Positioning System is used to _________.
determine latitude and longitude, measure altitude, and position storms, currents, and tides
The silica rich oozes of the Pacific Ocean are due to _____ at high latitudes and _____ at low latitudes.
diatoms; radiolarians
A fathom is a unit of _______.
distance
Longitude is given in degrees _________.
east and west of the prime meridian
Identify all of the different observations used to support Harry Hess' theory of seafloor spreading.
epicenters, mid ocean ridges,and deep trenches
The _______ of phytoplankton and zooplankton contribute to marine sediments.
fecal pellets
If ocean water were incompressible, sea level would stand _____ its present level.
greater than
Flat-topped, submerged seamounts are reffered to as ______.
guyots
A great circle can be described as _______.
having its center at Earth's center and being the shortest path between two points on Earth's surface
Extreme variation in the ocean's temperature is prevented by the water's _______.
heat capacity
Where does volcanic activity occur?
hotspots, ocean-ocean convergence, ocean-continent convergence, ocean-ocean divergence, ocean-continent divergence
A water molecule can bond with other water molecules by _______ bonds.
hydrogen
Which type of sediment is the greatest contributor, on a world scale, to the sediments of the neritic zone?
hydrogenous
What type of material is thought to contribute the larger size of the outer planets relative to the inner planets?
ice
The density of Earth materials _______ as the core is approached.
increases
Which of the Earth's layers has the greatest density?
inner core
The trailing margin of a continental landmass ____ than its leading margin.
is wider, shows less tectonic activity, and is more stable
A Secchi disk is used to measure the attenuation of _____.
light
When talking about plate tectonics, which of the Earth's layers comprises the plates?
lithosphere
The crust and the mantle are divided into the following layers in order of increasing depth:
lithosphere, asthenosphere, and mesosphere
Manganese nodule mining has not developed because of _______.
low international market prices in metal, unresolved ownership problems, and technical and developmental costs
Which layer of the Earth contains the greatest mass?
mantle
Which of Earth's layers contains the greatest volume of material?
mantle
Higher seafloor heat flow values are found _____.
near ocean ridge systems
Diatomaceous sediments are _______.
none of these are correct
Which of the following are found along subduction zones?
oceanic trenches, active earthquake zones, and island arc systems
The oceans' oldest sediments are found ________.
on top of the basalt layer, far from spreading centers
The area north of 66 1/2 degrees N is in darkness when the sun is directly _______.
over 23 1/2 degrees S
Red clay obtains its characteristic color from ________.
oxidation of iron
Manganese nodules are ______.
pelagic hydrogenous sediment
The mechanism causing lithospheric plates to move is thought to be _________.
produced by convection cells in the mantle
Which situations cause an ion to have a long residence time in oceans?
rapid reaction with other substances
Side scan sonar images are the product of the _________.
reflectivity of the material, depth of the water, and angle at which the sound strikes the object.
Sediments found on the seafloor and attributed to processes no longer in existence are called ______.
relict sediments
The residence time for water in any of Earth's principal reservoirs can be calculated by dividing _______.
reservoir volume by rate of water supply
Thinning of the Earth's crust and the resulting faulting is called ______.
rifting
Density of seawater increases as ______.
salinity and pressure increase and temperature decreases
The seabed is presently being mined in the US for ________.
sand and gravel
Which processes cause surface seawater to increase in density?
sea ice formation and surface water evaporation
Acoustic profiling is used to study _________
sediment distribution
Lithification of sediments produces ______.
sedimentary rock
The continental rise is a product of ________.
sedimentation
What are turbidites?
sediments deposited by a turbidity current, showing a pattern of coarse particles at the bottom, grading gradually upward to fine silt or mud
Which method is being used to investigate the structure of the mantle?
seismic tomography
A fixed volcanic hot spot on Earth tends to produce a ______ on a moving plate.
series of volcanic peaks
Magnetic stripes on the seafloor are created at _______.
spreading centers
The process of changing ice directly to water vapor is known as ______.
sublimation
Turbidity currents produce some ________.
submarine canyons
Inactive volcanic seamounts on top of the oceanic crust will ______.
subside with time
The _______ of a substance is a measure of the average kinetic energy of the atoms and molecules in the substance
temperature
Crustal fragments with a history distinct from adjoining crustal fragments are known as _____.
terranes
Seventy five percent of all marine sediments are _______.
terrigenous
Why do small particles descend to the seafloor at rates exceeding expectation?
the particles attract each other and the particles are incorporated into the fecal pellets of small animals
Plates move horizontally past each other along _______.
transform faults
A sediment deposit close to the continental rise having a coarse material overlaid by successively finer materials of nonmarine origin is called a ________.
turbidite
The sun stands directly above the equator ________.
twice each year
Which phase change reaction requires the most energy?
vaporization
The deep-ocean trenches are usually associated with ______.
volcanism, island arc systems, and earthquakes
An area drawn on a hypsographic curve equates to a(n) ______.
volume of land or water
Which of the following materials has the highest specific heat?
water
