Geology "Final"
Which statement about the photic zone is true?
The photic zone has sufficient sunlight for organisms to photosynthesize.
Which statement about valley glaciers is true?
They tend to flow faster than continental glaciers.
What happens when a wave enters shallow water?
Wavelength decreases, wave height increases, and wave speed decreases.
A glaciers budget is balanced when ____.
additions to the zone of accumulation equal losses in the zone of wastage
Ice Ages ____.
are the result of variations in the amount of solar heat received
A deposit of unconsolidated sediment that extends landward from low tide to a change in topography or to where permanent vegetation begins is a(n) ____.
beach
A glacial landform that forms at the head of glacial valleys or troughs is called a(n) ____.
cirque
Which of the following is an erosional feature of glaciers?
cirques
The deep seafloor is primarily composed of ____.
clays and biological oozes
The densest ocean water is ____.
cold and very saline
Sediment is lost from the nearshore zone primarily by ____.
deposition into submarine canyons and offshore transport
Wide beaches, deltas, and barrier islands are characteristic of ____ coasts.
depositional
What type of coast is straight and has marine terraces?
emergent coast
Which of the following is a depositional feature of glaciers?
end moraine
Which type of glacial deposit was formed by running water?
eskers
The area within 200 nautical miles of its shoreline to which the U.S. claims all mineral resources is called the ____.
exclusive economic zone
Sea level has fallen dramatically since the Pleistocene Epoch.
false
There is good evidence that variation in solar energy, as evinced by sunspot activity cycles, is responsible for short-term climatic variations.
false
A terminal moraine marks the ____.
farthermost point of a glacier's advance
The distance wave-producing winds blow over a continuous body of water is the ____.
fetch
The largest waves are generated when ____.
fetch is large, wind speed is high, and wind duration is long
Ocean water evolved ____.
from condensation of water vapor from volcanic eruptions
What term describes the straight scratches on rock surfaces created by glacial abrasion?
glacial striations
The movement of water within a wave travels ____.
in a circular path at a depth of one-half the wavelength
In a cross-section of a glacier, where do the greatest flow velocities occur?
in the few tens of meters below the surface
Emergent coasts form when ____.
land rises or sea level falls
The most important process by which glaciers move is ____.
plastic flow
Although sea level is rising worldwide, the amount of rise varies by location. What two factors influence the amount of sea level rise at a local scale?
rate of uplift or subsidence and volume of water in oceans
If wastage is greater than accumulation, a glacier is said to be ____.
retreating
Worldwide, the majority of glaciers are ____.
retreating
What are narrow surface currents that flow in the same general direction as the approaching waves?
rip currents
A glacial landform produced primarily by plucking rocks on the downstream side and smoothing by the glacier on the upstream side is called a(n) ____.
roche moutonée
The oceans are most likely to get saltier if ____.
runoff from lakes and streams is increased
A glacier forms when ____.
snow accumulates to form ice, and the ice mass begins to flow under its own weight
The three stages involved in the formation of glacial ice are, in order, ____, ____, and ____.
snowfall; firn; glacial ice
What is a lake formed within a cirque?
tarn
Spring tides are tides ____.
that result from the combined gravitational force of the aligned Moon and Sun
The health of a glacier and the glacial budget are determined primarily by ____.
the amount of snowfall and temperature
Ocean energy is difficult to harness because ____.
the energy is not very concentrated
What happens to ice movement within a glacier when the glacier is retreating?
the ice flows downhill
Mountain valleys subjected to glaciation are typically shaped like ____.
the letter "U"
Salinity of seawater is a measure of ____.
the total quantity of dissolved solids
What is a spit that connects an island to the mainland called?
tombolo
Continental glaciers generally flow on the order of centimeters to meters per day.
true
Glaciers are geologically important because they erode, transport, and deposit so much material.
true
Glacial till is ____.
unstratified sediment deposited directly by a glacier
Which term describes vertical ocean circulation, in which water moves from deep to shallow?
upwelling
The most useful way to measure seafloor depth is to ____.
use an energy source to produce strong waves that will reflect from the seafloor and layers beneath the seafloor
A glacier that is unconfined by topography and has tributaries is a(n) ____.
valley glacier
Short-term climatic changes like the Little Ice Age are poorly understood. One hypothesis for why short-term climatic events occur is ____.
variations in solar radiation
Beaches change seasonally in response to changes in ____.
wave intensity
Water in waves is displaced from the circular orbits when ____.
waves enter progressively shallower water
Surface ocean currents are ____ driven, and deep ocean currents are ____ driven.
wind; pressure
A beach with a small berm, coarser sediment, and offshore sand bars is a(n) ____.
winter beach
How much of Earth's surface is covered by glaciers?
10%
When did the Pleistocene Ice Age end?
11,700 years ago
Geologic evidence suggests that oceans formed by at least ____.
3.5 billion years ago
What amount of oil from U.S. production comes from the Gulf of Mexico?
30%
A glacier begins to flow when the ice reaches what critical thickness?
40 meters
If wavelength is 18 meters, wave base is located at ____.
9 meters