Отправлено: 03.02.09 13:47. Заголовок: Influence of wettability on water saturation modelling

Journal of Petroleum Science and Engineering
Vol: 24, Issue: 2-4, December, 1999 Bibliographic Page pp. 243-253

Title: Influence of wettability on water saturation modelling
Authors: Stalheim, S.O.a; Eidesmo, T.a; Rueslеtten, H.a
Affiliations: a. Statoil, Strandveien 4, P.B. 273, 7501 Stjordal, Norway
Keywords: wettability; water; saturation
Abstract (English): In order to calculate water saturation using standard equations (e.g., Archie; Waxmann and Smits), the saturation exponent (n) and the cementation exponent (m) must be determined. These exponents are normally derived from electrical measurements made on cleaned core plugs [i.e., formation factor (FF) and resistivity index (RI)]. However, numerous papers have shown that coring and cleaning processes may significantly alter the wettability of the cores. In this case, the measurements of n and m are no longer representative of the in situ conditions and estimates of the water saturation may thus be seriously wrong. We will demonstrate that wettability will have a serious impact on log estimated water saturation, and that even a very rough estimate of the wettability can significantly reduce the error in estimated water saturation. The cited field examples are taken from North sea sandstone reservoirs.
Publisher: Elsevier Science
Item Identifier: S0920-4105(99)00046-7