Chapter 15 Flashcards
What is a recharge zone?
Any area where water infiltrates Earth’s surface and reaches an aquifer below
Recharge zones are crucial for maintaining aquifer levels.
What characterizes a confined aquifer?
A porous, water-bearing layer of rock, sand, or gravel trapped between less permeable layers
The water in confined aquifers is under great pressure.
How does an unconfined aquifer differ from a confined aquifer?
An unconfined aquifer has no impermeable upper layer, allowing water to be readily recharged
This results in lower pressure compared to confined aquifers.
What is the largest known aquifer?
The Ogallala Aquifer
It is located under the Great Plains of the United States.
What ecological role does surface water play?
Surface water is vital for survival and ecological systems
It interacts with groundwater and supports various ecosystems.
What is runoff?
Water that falls as rain, emerges from springs, or melts from snow and flows over land
Runoff converges to form streams, creeks, or rivers.
Define a tributary.
A smaller river flowing into a larger river
Tributaries contribute to the overall watershed.
What is a watershed?
The area of land drained by a river system and all its tributaries
Also known as a drainage basin.
What is the role of springs in the water cycle?
Springs allow groundwater to surface, often maintaining stream flow
They are critical during dry conditions.
Fill in the blank: An _______ well taps into confined aquifers to mine water under pressure.
artesian
Artesian wells are named after the region of Artois in France.
What is the impact of unsustainable water withdrawals from aquifers?
Threatens long-term use for agriculture
Overpumping can lead to depletion of the aquifer.
What is the water table?
The upper surface of the saturated zone in an aquifer
It fluctuates based on recharge and withdrawal.
True or False: Surface water can become groundwater.
True
This occurs through the process of infiltration.
What are the components of a confined aquifer?
Upper confining layer (often clay) and lower confining layer (often clay)
These layers trap water, creating pressure.
How does groundwater become surface water?
Through springs and human-drilled wells
This process helps maintain wetlands and stream flows.
What is the significance of the Ogallala Aquifer for American agriculture?
It supports the most bountiful grain-producing region in the world
Its water is crucial for irrigation in the Great Plains.
