MULTIPLE APPROACHES TO CHARACTERIZING PORE CONNECTIVITY IN THE BOSSIER SHALE, EAST TEXAS

As one of the most important factors controlling fluid distribution and migration, the pore connectivity of shale matrix is influenced by pore size distribution and wettability. However, wettability of shale is complex due to its micro-scale distribution of matrix (minerals and organic matter) composition, it does not show an obvious relationship to the connectivity. To obtain a deep insight into the wettability-connectivity relationship, both mineral composition and organic matter are considered for Bossier shale in East Texas. A total of seven Bossier shale samples were collected from a well in San Augustine county over a vertical distance of 120 ft. Multiple approaches such as total organic carbon (TOC), X-ray diffraction (XRD), contact angle, mercury intrusion porosimetry (MIP), and spontaneous imbibition (SI) were used to investigate organic matter richness, mineral composition, wettability, pore size distribution, and connectivity. For the spontaneous imbibition test, deionized water and DT2 (n-decane: toluene at 2:1 in volume) were used as the imbibing fluids to demonstrate the effects of hydrophilic and hydrophobic fluids on the imbibition behavior of Bossier shale.