What characterizes an artesian well?

An artesian well is characterized by its ability to tap into a confined aquifer, which is an underground layer of water-bearing rock or sediment that is trapped between two layers of impermeable material. This configuration allows water to be under pressure. When a well is drilled into this aquifer, the natural pressure can cause the water to rise to the surface without the need for a pump, often resulting in the water level in the well being higher than the top of the aquifer itself.

This characteristic makes artesian wells unique and different from other types of wells. They are specifically designed to access confined aquifers where the water is under pressure. The presence of the impervious layers above the aquifer is crucial as it prevents the water from escaping and maintains that pressure.

The other answer choices highlight misconceptions. For example, tapping into a surface water source pertains to different forms of water extraction, and drawing water from the atmosphere does not relate to well drilling. Furthermore, while irrigation can be one use of an artesian well, it is not exclusive to this purpose, as artesian wells can supply water for various applications, including municipal and domestic use.