| Fluid-rock interaction plays a critical role in the evolution of rock permeability. Among the most important engineering applications are flow of hydrocarbons in petroleum reservoirs, thermal energy extraction, water supply exploration, and toxic and radioactive waste management. Important natural examples include multiple dikes and sheeted intrusions, natural hydraulic fracturing, water circulation in the oceanic crust, and ore deposits formation. In this thesis, new effects associated with stress and temperature dependent permeability of fractured rock were studied. The conducted asymptotic and numerical analysis supported by field and laboratory observations resulted in better understanding of these phenomena and useful recommendations for science and engineering.; In particular, the evolution of permeability as a result of the fluid-rock interaction was considered for hydraulic fracturing, fluid flow through jointed layered rocks, and water circulation in seafloor hydrothermal systems. It was shown that in all three cases fluid-rock interaction plays a critical role and must be taken into account by accurately computing changes of fracture apertures. It was also shown that elastic interaction between the segments significantly affects multisegmented hydraulic fracture dimensions and driving pressure and can alter the permeability of jointed layered rocks by orders of magnitude. Fracture closure due to thermal stresses can dramatically reduce water flow through the oceanic crust changing the regime of heat transfer near mid-oceanic ridges and the temperature of the water discharging from the hydrothermal vents. Fracture closure by internal fluid pressure—an effect never previously reported—was found in the study of parallel, closely located fractures. Asymptotic formula that is simple but accurate for all possible parameter ranges was suggested for the permeability of parallel joint sets.; These findings may have a significant impact on hydraulic fracture simulation and design, as well as on permeability evaluation in petroleum and water resources engineering. They are also critical for understanding the nature of multiple volcanic intrusions and permeability evolution in oceanic crust and sedimentary basins. |
