Final answer:
Artesian wells occur when water from a pressurized aquifer rises to the surface without the need for pumping, due to the water pressure above the aquifer.
Step-by-step explanation:
The type of wells described, where the water pressure surface (potentiometric) lies above the ground surface, allowing water to rise above the top of the aquifer without any pumping, are known as artesian wells. Artesian wells tap into confined aquifers where the water is under sufficient pressure to rise on its own. This can occur when the aquifer is trapped between layers of impermeable materials such as clay or rock, and is inclined so that one end receives water recharge. Because of this pressure, when the aquifer is penetrated by a well, the internal pressure is often enough to push the water up through the well without the need for mechanical pumps.