Aquifers come in many shapes, sizes, and “flavors”. For example, some aquifer systems span hundreds – or even thousands – of kilometers across several states or nations and may include multiple individual layers of rock or sediment that total thousands of meters in thickness. Other aquifers may be restricted to a few kilometers within a stream valley, and be only a few meters thick.
Nonetheless, there are some important common features of different kinds of aquifers. In this section of the module, we provide a basic overview of aquifers: What is an aquifer? What are the different types of aquifers, and what is their anatomy?