Fracturing of various types of rocks by water and by CO2 are presented with consideration of thermoporoelasticity. The phase-field approach with incorporation of critical energy release rate is the basis of the rock failure and fracture propagation. There are advantages in formulation based on the Euler-Lagrange equation in simulation of fracturing. The mixed finite element may be a natural choice for discretization in fracturing. We can predict fracture branching without parameter adjustment. At superhot temperatures found in many regions of the world, the estimate of renewable geothermal energy exceed hydrocarbon energy resources. At higher temperatures even without thermal stress, fracture intensity from fracture branching and from natural microfractures may provide the path for effective heat extraction. At superhot temperatures, there may be a significant reduction in breakdown pressure. CO2 fracturing is even more effective than water fracturing in such conditions. Lower fracturing pressure reduces seismic activity and helps with safety of fracturing.
Fracturing of various types of rocks by water and by CO2 are presented with consideration of thermoporoelasticity. The phase-field approach with incorporation of critical energy release rate is the basis of the rock failure and fracture propagation. There are advantages in formulation based on the Euler-Lagrange equation in simulation of fracturing. The mixed finite element may be a natural choice for discretization in fracturing. We can predict fracture branching without parameter adjustment. At superhot temperatures found in many regions of the world, the estimate of renewable geothermal energy exceed hydrocarbon energy resources. At higher temperatures even without thermal stress, fracture intensity from fracture branching and from natural microfractures may provide the path for effective heat extraction. At superhot temperatures, there may be a significant reduction in breakdown pressure. CO2 fracturing is even more effective than water fracturing in such conditions. Lower fracturing pressure reduces seismic activity and helps with safety of fracturing.