Definitions of fluid contacts are based on comparison to [[capillary pressure]] curves ([[:file:fluid-contacts_fig1.png|Figure 1]]). The ''[[free water surface]]'' is the highest elevation at which the pressure of the hydrocarbon phase is the same as that of water. The ''hydrocarbon-water'' (''[http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%20name&filter=oil-water%20contact oil-water]'' or ''[http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%20name&filter=gas-water+contact gas-water]'') ''contact'' is the lowest elevation at which mobile hydrocarbons occur. The ''[[What is a reservoir system?#Waste and transition zones|transition zone]]'' is the elevation range in which water is coproduced with hydrocarbons. The ''[http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%20name&filter=gas-oil%20contact gas-oil contact]'' is the elevation above which gas is the produced hydrocarbon phase. | Definitions of fluid contacts are based on comparison to [[capillary pressure]] curves ([[:file:fluid-contacts_fig1.png|Figure 1]]). The ''[[free water surface]]'' is the highest elevation at which the pressure of the hydrocarbon phase is the same as that of water. The ''hydrocarbon-water'' (''[http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%20name&filter=oil-water%20contact oil-water]'' or ''[http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%20name&filter=gas-water+contact gas-water]'') ''contact'' is the lowest elevation at which mobile hydrocarbons occur. The ''[[What is a reservoir system?#Waste and transition zones|transition zone]]'' is the elevation range in which water is coproduced with hydrocarbons. The ''[http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%20name&filter=gas-oil%20contact gas-oil contact]'' is the elevation above which gas is the produced hydrocarbon phase. |