Energy geotechnology: Implications of mixed fluid conditions

Multi phase fluids are common in energy-related geotechnical problems, including gaswater, gas-oil, ice-water, hydrate-water, and oil-water fluid conditions. The generalization of classical unsaturated soil mechanics concepts to energy geotechnology requires physical understanding of surface tension, contact angle, capillary pressure, solubility and nucleation. Eventually, these pore-level processes affect the granular skeleton. Together, pore and particle-scale interactions upscale through the sediment structure to affect its macroscale response. Possible emergent phenomena include fluid percolation, residual saturation and recovery efficiency; fluid driven fractures, lenses, fingering and pipe formation; bubble migration and bottom blow up. presented in the following section capture the essential characteristics; references are provided for detailed information. 2 AToMIC-SCAlE PhEnoMEnA Geotechnical implications of mixed-fluid conditions arise from interactions at the atomic scale where surface tension and contact angle are defined. Interfaces are in a state of dynamic equilibrium: molecules are continuously jumping from one phase to the other. The average residing time for a