Enter the resistivity index and the saturation exponent into the calculator to determine the water saturation.

Water Saturation Formula

The following formula is used to calculate water saturation.

Sw = ((1/Ir) ^n) *100

  • Where Sw is the water saturation (%)
  • Ir is the resistivity index
  • n is the saturation exponent

What is water saturation?


Water saturation is a measure of the percentage of a medium that is saturated with water.

How to calculate water saturation?

Example Problem:

The following example outlines how to calculate a water saturation ratio.

First, determine the resistivity index. In this example, the index is measured to be 2.5.

Next, determine the saturation exponent. The saturation exponent for this problem is found to be 3.5.

Finally, calculate the water saturation using the formula above:

Sw = (1/Ir) ^n

Sw = (1/2.5) ^3.5

Sw = .04 = 4%