*5.1.2 Initial water saturation*

The initial amount of water present in matrix of rocks has been investigated by several researchers to ascertain its impact on the quantum of imbibition, but findings have been inconsistent, thus making it difficult to draw any conclusions. Whereas Blair [73] and Li et al. [74] found that an initially high water saturation of formation led to lower volumes of imbibed water, Cil et al. [75] and Zhou et al. [76] found the opposite in their experiments. Other works by Li et al. [74], Viksund et al. [77] and Akin et al. [78] also concluded that initial water saturation had no effect on imbibition of water by the formation. They explained that volume of water imbibed is a function of capillary pressure and effective permeability but these show an inverse and direct relation with water saturation respectively. The amount of water imbibed is therefore not controlled by a single parameter, but will depend on which of the two variables is dominant in any given formation. In this regard, they concluded that the influence of initial saturation on imbibition should be ascertained for every formation independently.

*Review of Geochemical and Geo-Mechanical Impact of Clay-Fluid Interactions Relevant… DOI: http://dx.doi.org/10.5772/intechopen.98881*