Development of a Modified Capillary Pressure J-Function


By Noaman El-Khatib.


Capillary pressure curves are represented by the equation Pc=a / Sw-Swi)b. It is shown that for the Leverett J–function to produce a single correlation, the tourtuosity the ire-ducible water saturation and the saturation exponent b must be the same for the different formation amodified capillary pressure function J* is introduced that incorporates the tor– tuosity and irreducible water saturation In its. Definition the modified function is correlated with the normalized saturation SD so that atl curves will have their vertical asymptotes at a single point SD=O. The modified function represents a significant impro- vement over the original one since it is now sufficient to have the value of the saturation exponent b be the same for two samples to get the same correlation. This was verified by analyzing data from the literature and compating the two correlations. A modified linear regression by means of weighted least


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