Answer:
The result of pressure within a confined aquifer that creates a potentiometric surface
Step-by-step explanation:
There are conditions under the Earth's surface, where porous rock layers are tilted and also have a confining, less porous, rock layer about the their boundary, forming a confined aquifer. The existing pressure in the aquifer is therefore confined within the water and the porous rock layer, such that drilling into the pressurized aquifer leads to the water rising under the pressure existing in the aquifer, to a potentiometric surface which is above the actual underground level of the aquifer