Changes

[[File:Formula 4.png|200px|thumbnail|center]]

[[File:Formula 4.png|200px|thumbnail|center]]

If the hydrocarbon pressure equal to the water capillary pressure equal with zero. This point is called as a free water level (FWL).

If the hydrocarbon pressure equal to the water capillary pressure equal with zero. This point is called as a free water level (FWL).

        <math>\text{P}_\text{c} = \text{P}_\text{hc} - \text{P}_\text{w}</math>

: <math>\text{P}_\text{c} = \text{P}_\text{hc} - \text{P}_\text{w}</math>

Changes in capillary pressure against the reference position below the hydrocarbon zone can be seen as a function of:

Changes in capillary pressure against the reference position below the hydrocarbon zone can be seen as a function of:

[[File:Formula5.png|200px|thumbnail|center]]

: <math>h = \frac{P_c}{0.433(\rho_w - \rho_{hc})}</math>

To determine fluid contacts must be known threshold value of pressure (Pct) is known from the curve Pc against Sw.  

To determine fluid contacts must be known threshold value of pressure (Pct) is known from the curve Pc against Sw.  

[[File:Formula6.png|350px|thumbnail|center]]

[[File:Formula6.png|350px|thumbnail|center]]