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 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>