This study addresses some of the problems associated with the Repeat Formation Tester (RFT) tool. Although the RFT detects the filtrate phase pressure at the sandface, this may differ from the oil phase pressure in the undisturbed formation as a result of capillary interface effects, formation wettability effects and supercharging (the pressure superimposed on the initial formation pressure as a result of the viscous flow of filtrate). While capillary driven flow may be significant in high permeability formations, the effect of capillary gradients in low permeability formations may be neglected and the Buckley-Leverett immiscible displacement equation used to model the invasion process. From this basis a modified theory of supercharging is developed.
|Title of host publication||Proceedings - European Petroleum Conference|
|Number of pages||16|
|Publication status||Published - 1984|