A well capable of producing oil or gas by its own energy without the aid of a mechanical pump. Normally a pump is put on the well after the pressure reduction inhibits the rate of production.

A well that produces through natural reservoir pressure and does not require pumping.

A well in which the static water level is above ground level.

A well that taps an aquifer that is under enough pressure to force water to the surface. Caused when the aquifer has a recharge area at a higher elevation.

A well from which oil or water flows without pumping or artificial lifting.

A well drilled into a confined aquifer with enough hydraulic pressure for the water to flow to the surface without pumping. Also called an Artesian well.

a well which produces oil or gas without any means of artificial lift.

A well that produces oil or gas by its own reservoir pressure rather than by use of artificial means

A well from an artesian aquifer in which the water is under sufficient pressure to rise above the ground surface.