An aquifer is typically some layer of permeable rock or unconsolidated material like gravel or sand wherein water that trickles down from the earth’s surface tends to hang out for a while. We like aquifers because by tapping into an aquifer via a well we get fresh water to drink, irrigate crops, cook, clean, fill water balloons, etc.
Aquifers can come in a couple of different flavors, two of which are confined and unconfined. A confined aquifer typically has a layer of finer grained sediments on top if it called an aquitard. This aquitard layer serves as almost a cap on the aquifer below it. Water can still permeate an aquitard, but it does so very…very…slowly. If water isn’t let through at all, the layer is called an aquiclude. Aquitards can be layers of clay or silt or whatever fine grained sediment you fancy.
Unconfined aquifers are just like what they sound: an aquifer that isn’t confined by an aquitard. These aquifers seem so footloose and fancy free. No, but they do contain water that is still a viable source for wells and such. Unconfined aquifers can sometimes be found living above confined aquifers, but below the water table. Think of unconfined aquifers as the confined aquifer’s noisy upstairs neighbor who’s always tromping around in high heels at all hours of the night. I have one of those neighbors. Man, I hate those jerks.
Aquifers can come in a couple of different flavors, two of which are confined and unconfined. A confined aquifer typically has a layer of finer grained sediments on top if it called an aquitard. This aquitard layer serves as almost a cap on the aquifer below it. Water can still permeate an aquitard, but it does so very…very…slowly. If water isn’t let through at all, the layer is called an aquiclude. Aquitards can be layers of clay or silt or whatever fine grained sediment you fancy.
Unconfined aquifers are just like what they sound: an aquifer that isn’t confined by an aquitard. These aquifers seem so footloose and fancy free. No, but they do contain water that is still a viable source for wells and such. Unconfined aquifers can sometimes be found living above confined aquifers, but below the water table. Think of unconfined aquifers as the confined aquifer’s noisy upstairs neighbor who’s always tromping around in high heels at all hours of the night. I have one of those neighbors. Man, I hate those jerks.
There's your quick and dirty look at aquifers. Ta-Da!
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