Changes

==Effect on seal capacity==

==Effect on seal capacity==

The height of the [[hydrocarbon column]] (h) in the above equations is a theoretical maximum. The actual height is less because of the effect of the reservoir. If the reservoir itself had zero [[displacement pressure]], the height of the hydrocarbon column would attain the theoretical maximum and the oil=water contact would coincide with the [[free water level]]. If the reservoir has some displacement pressure greater than zero, then the height of the hydrocarbon column is less than the theoretical maximum, or

The height of the [[hydrocarbon column]] (h) in the above equations is a theoretical maximum. The actual height is less because of the effect of the reservoir. If the reservoir itself had zero [[displacement pressure]], the height of the hydrocarbon column would attain the theoretical maximum and the [http://www.glossary.oilfield.slb.com/en/Terms.aspx?LookIn=term%20name&filter=oil-water+contact oil-water contact] would coincide with the [[free water level]]. If the reservoir has some displacement pressure greater than zero, then the height of the hydrocarbon column is less than the theoretical maximum, or

:<math>\mbox{h} = \left(\frac{\mbox{P}_{\rm ds} - \mbox{P}_{\rm dr}}{\rho_{\rm w} - \rho_{\rm h}}\right) 0.433</math>

:<math>\mbox{h} = \left(\frac{\mbox{P}_{\rm ds} - \mbox{P}_{\rm dr}}{\rho_{\rm w} - \rho_{\rm h}}\right) 0.433</math>