Geology Lab Exam 2 Schenk
2%
A 50-year flood is one that has a _______ chance of occurring every year.
Flood
A _______ occurs whenever the volume of water flowing in a channel is greater than the channel's storage capacity.
Intermittent Stream
A blue line with dashes and dots along it represents a(n)
Levee
A raised embankment along a river channel, either natural or man-made, that holds back flood waters is called a _______.
1 unit on the map equals 1000 units in the real world
A ratio scale of 1:1000 on a topo map indicates that _______.
True
A river that has been channelized actually has a greater risk of flooding than if the river's natural course had been left unchanged.
Stage
A river's _______ is defined as the height of the water level in the river above some defined zero point, usually sea-level or the river's stream bed.
Depression
A set of tick marked circles inside circles on a topographic map indicate a
Liquefaction
A very dangerous phenomenon that occurs when seismic waves travel through water-saturated sediment in which the sediment as a whole acts as a fluid, is called _____
True
During an earthquake, buildings oscillate. If the frequency of this oscillation is close to the natural frequency of the building, resonance may cause much greater damages.
Ground Amplification
During an earthquake, the amount of ground shaking can vary depending on the material through which the seismic waves are traveling. For example, solid bedrock will experience minimal shaking, while loose sand. mud, and fill will experience great shaking. This phenomenon is called _______
1994
During the past 99 years, what year you saw the greatest flood on the Flint River at Montezuma?
The same as any other point along that line.
Each point along a topographic line has an elevation of
By contour lines that form V's which point upstream
How are streams indicated on a topographic map?
Silica (Si02) content
In addition to temperature, magma viscosity is also controlled by________
Composite Cone (Stratovolcano)
Mount Rainier in Washington State is a _______
Steeper the slope.
On a topographic map, the closer the contour lines the _______.
False
River downcutting will continue as long as there is water in the channel.
Data Points
The accuracy of a flood-frequency model (best-fit line on a flood-frequency graph) depends on how many _______ are used to construct the model. The more _______, the more accurate the model. (Note: the same answer fills in both blanks).
Gradient
The difference in elevation between two points on a topographic map, divided by the horizontal distance between those two points, and expressed as ft/mile or m/km is called________
Erosion
The headwaters of a river is known as the zone of _____, because the steepest gradients and fastest velocities are found there.
Contour Interval
The regular standard change in elevation between any two adjacent contours is known as the _______.
Drainage Divides
Topographic high points that separate distinct drainage networks are called____________.
False
Water flows faster in the inner side of a meander river bend and erode the inner side of the river bank.
Riparian
Wetlands adjacent to streams, usually on the stream's floodplain, are called _______ wetlands
Lava flows that people can outrun, but vegetation and buildings can't.
What poses the greatest hazard living next to a shield volcano?
Widely-spaced contour lines
What type of contour pattern would you expect to see on areas identified as floodplains?
290 ft.
What was the elevation of the Flint River during that greatest flood?
All along the Pacific Coast and Central Mississippi River Valley.
Which of the following areas of the United States are highly susceptible to earthquakes?
Lahars
_______ are volcanic mudflows that are typically triggered by heavy rainfall in tropical regions or by the melting of glaciers during effusive lava eruptions on stratovolcanoes
Volcanic Ash
_______ in the upper troposphere can gum up jet engines in flight and may even cause temporary global cooling by reflecting incoming solar radiation. Question
Basaltic; shield
_______ lava is low viscosity, has a temperature of 1200°C, and typically forms _______ volcanoes.