Geology Exam 3
What percentage of the Earth's land surface is currently covered by glacial ice?
10 %
When was the last glacial maximum
18,000 years ago
What percentage of Earth's liquid freshwater is in the form of groundwater?
96%??
What percentage of Earth's water is in the form of sea water?
97.2 %
What is the geological definition of a stream?
A channelized body of water flowing down gradient
What is permeability?
Ability to transmit water
Which part of a stream's sediment load moves the slowest?
Bed load
Which of the following materials is most readily dissolved by water?
Calcite
_______ is the maximum load of solid parcels a stream can transport per unit time.
Capacity
Which of the following materials would make the best aquitard?
Clay
______ is a measure of a stream's ability to transport particles based on their size rather than quantity.
Competence
What feature develops if a well is withdrawing more groundwater than an aquifer can naturally replace, resulting in a dimple in the water table?
Cone of depression
The______ is an elevational point that divides an entire continent into large drainage basins.
Continental Divide
The general term used to describe cave deposits is
Dripstone
_____ are flat areas along streams that are created by the deposition of alluvium and is subject to periodic inundation.
Floodplains
During what periods would streams see the greatest erosion and transportation of sediment?
Floods
In order for an aquifer to be useful for reliable water extraction, what kind of porosity and permeability should it have?
High porosity, high permeability
What force pushes groundwater from pore space to pore space when below the water table?
Hydraulic gradient
The________ describes the path water takes as it moves between the land, the ocean, and the atmosphere.
Hydrologic Cycle
Which of the following uses the largest percentage of the Earth's groundwater?
Irrigation
Which of the following is not part of the MIlankovitch Cycle?
Isostacy
Streams generally receive their water from two sources. What are these two sources?
Overland flow and ground water
In what spaces or vids does most groundwater reside?
Pore spaces and fractures
______ is when groundwater is being replenished. ______ is when groundwater is flowing back toward the surface.
Recharge; Discharge
Which environmental issue most commonly affects groundwater aquifers in coastal or island areas?
Saltwater contamination
Which of the following locations does NOT currently have glaciers?
Scotland
What is the ultimate base level?
Sea level
Karst features like caves and sinkholes are an example of_____ porosity
Secondary
Which of the following particle sizes is most likely to make up a stream's suspended load?
Silt
Which of the following is an example of a speleothem?
Stalagmite
Glaciers form because of the accumulation of large amounts of ice and snow. Which of the following provides the most water needed to create glacier?
Streams??
If gravity pulls infiltrating water downward, what force allows water to to be pulled upward at the capillary fringe?
Surface Tension
What is the longitudinal profile?
The cross-sectional area from the headwaters to the mouth.
What is base level?
The downward limit of erosion
What is the mouth of a stream?
The location where one stream flows into another body of water.
What will happen to the water level in the stream if the water table is below the level of the stream channel?
The stream will lose water to the groundwater system.
Which household function has the highest daily water consumption?
Toilets
What shape do glacial troughs generally display?
U
How will channel velocity change along the longitudinal profile of a stream?
Velocity will start low and gradually increase toward the mouth due to increasing discharge downstream
What is porosity?
Volume of pore space in a material
What is Infiltration?
Water Soaking into the ground
How will water table respond when there is a drought?
Water table will fall
How will water table respond if it is a wet spring
Water table will rise
What is a flood?
When discharge in a river exceeds the rivers capacity.
