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==Free water level==

==Free water level==

{{main|Free water level}}

{{main|Free water level}}

The '''free water level''' is located at the base of a hydrocarbon column and the transition zone. Above this level, the reservoir produces water alone, hydrocarbon and water, or hydrocarbon alone on a production test. Below this level lies the aquifer of a water-drive reservoir system. It produces water only. Zero buoyancy pressure exists at this level or below.

The '''free water level''' is located at the base of a hydrocarbon column and the transition zone. Above this level, the reservoir produces water alone, hydrocarbon and water, or hydrocarbon alone on a production test. Below this level lies the aquifer of a [[Drive_mechanisms_and_recovery#Water_drive|water-drive]] reservoir system. It produces water only. Zero [[buoyancy pressure]] exists at this level or below.

==References==

==References==