Although central to accurate prediction of subsurface porosity and permeability, assessing the influence of oil emplacement on compaction, solution, and cementation processes in sandstone has remained enigmatic. Sathar et al. describe a series of lab experiments that systematically alter the ratio of brine to oil and quantify volumetric strain and characterize its expression. The results illustrate that as brine:oil ratio decreases, the generally increasing strain is accommodated less by pressure solution and more by grain fracturing, but only to a 5:95 ratio, whereupon volumetric strain decreases. The results of this study suggest the important role of oil on the amount and character of compaction and cementation in sandstone.
The effect of oil saturation on the mechanism of compaction in granular materials: higher oil saturations lead to more grain fracturing and less pressure solution by Shanvas Sathar, Richard H. Worden, Daniel R. Faulkner, and P. Craig Smalley