102 Chapter 14 Groundwater — Physical Geology – 2nd Edition
Chapter 14 Groundwater
After reading this chapter, completing the exercises within it, and answering the questions at the end, you should be able to:
- Explain the concepts of porosity and permeability and the importance of these to groundwater storage and movement.
- Describe the relative porosities and permeabilities of some common geological materials.
- Define aquifers, aquitards, confining layers, and the differences between confined and unconfined aquifers.
- Explain the concepts of hydraulic head, the water table, potentiometric surface, and hydraulic gradient, and apply the Darcy equation to estimation of groundwater flow rates.
- Describe the flow of groundwater from recharge areas to discharge areas.
- Describe the nature of groundwater flow in karst systems.
- Explain how wells are used to extract groundwater and the implications of over-pumping a well.
- Describe how observation wells are used to monitor groundwater levels and the importance of protecting groundwater resources.
- Distinguish between natural and anthropogenic contamination of groundwater.
- Describe some of the ways that groundwater can become contaminated, and how contamination can be minimized.
Figure 14.0.1 An artesian well emitting groundwater to the surface at the Baca National Wildlife Refuge, near Alamosa, CO.
As we saw in Chapter 13, fresh water makes up only 3% of the water on Earth. Approximately two-thirds of that is glacial ice and most of the rest is groundwater. We can’t live without water, and it’s easy to see that groundwater represents a critically important component of our water supply. Groundwater is not as easily accessed as surface water, but it is also not as easily contaminated as surface water. If more than 7 billion of us want to continue living comfortably here on Earth, we have to take great care of our groundwater and learn how to use it sustainably.
Media Attributions
- Figure 14.0.1: Wikimedia Commons
