Through-Flow Systems Unconfined and Confined

8 Through-Flow Systems Unconfined and Confined 2.8.1 Phreatic (Unconfined, Free Surface) Aquifers 

Phreatic aquifers have free communication with the aerated zone. The synonym free surface aquifer relates to the free communication between the aquifer and the vadose zone. An example is shown in Fig. 2.5. The term phreatic originates from the Greek word for a well. 

Phreatic aquifers are the most exploited type of aquifer and most of the hydrochemist s work is performed on them. Phreatic aquifers are the collectors of infiltrating recharge water, and this process is well reflected in 

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Confined aquifers are water-bearing strata that are sealed at the top and the bottom by aquiclude rocks of low permeability (Fig. 2.6). Confined aquifers are commonly formed in folded terrains (section 3.4) and have a phreatic section, where the aquifer rock beds are exposed to recharge infiltration, and a confined section, where the aquifer rock beds are isolated from the landscape surface by an aquiclude (Fig. 2.6). 

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