Effect of Discontinuous Shales on Reservoir Performance During Horizontal Waterflooding

We investigate quantitatively the effect of inclined and intersecting discontinuous shales on horizontal waterfloods, using generic, dimensionless twoand three-dimensional models. We focus upon whether the shales alter the sweep efficiency. We find that they have a significant effect only if they are continuous over large areas of the bedding surfaces and are steeply inclined to the flow, or if the displacement is highly unfavorable. We also find that two-dimensional simulations can significantly overestimate the effect of intersecting shales, because they assume that the shales are entirely continuous in the third dimension.