Nonsteady three‐phase immiscible fluid distribution in porous media

An experimental investigation was conducted to evaluate the three‐phase fluid distribution caused by a petroleum spill in an unconfined aquifer. The experiment consisted of introducing oil at the top of a vertical column of soil containing water and measuring the oil and water contents at various elevations and times. The static fluid distribution was then compared to the calculated distribution based on two‐phase capillary pressure versus saturation data obtained by a separate laboratory experiment. It was concluded that the water saturation at static equilibrium can be estimated satisfactorily by assuming it is a function of the capillary pressure between oil and water.