Modes of free convection in fractured low-permeability media

摘要: [1] Abundant data indicate significant fluid and solute fluxes across low-permeability shales in the Gulf of Mexico, precise mechanisms which are poorly understood. In this study, we analyze possible modes intrafracture interfracture free convection that may occur fractured layers, such as shales. Fracture spacing, fracture aperture, shale thickness, density gradient unit shown to play key roles governing transport processes. All (parallel plane, perpendicular between fractures on larger layer scale) theoretically for reasonable hydrogeologic parameters. Free parallel plane is be dominant (and most likely) mode convection, requiring only very modest salinity differences onset occur. Least likely plane. The results presented here suggest not uncommon thick sequences, Mexico Basin. An important consequence these findings analyses do consider both significantly underestimate likelihood occurrence convection. These have implications study processes media associated numerical modeling analyses.