Hydraulic fracture induced by water injection in weak rock

A two-dimensional model of a hydraulic fracture propagating in weakly consolidated, highly permeable reservoir rock during waterflooding operation is described this paper. The recognizes the essential differences that exist between class fractures and conventional fracturing treatments oil gas wells, namely: (i) large-scale perturbations pore pressure associated poroelastic effects caused by extended injection time; (ii) extremely small volume fluid stored compared with injected volume; (iii) leakage water from both borehole fracture. consists set equations encompassing linear elastic mechanics, porous media flow lubrication theory. Three asymptotic solutions applicable at different time regimes are found theoretically, numerical results obtained discretized governing equations. solution reveals does not evolve monotonically, as it increases early radial-flow regime but decreases late fracture-flow regime. Thus, peak correspond to breakdown formation, usually assumed, rather transition two flow. However, problem exhibits an extreme sensitivity scales on dimensionless rate $\mathcal {I}$ . If {I} \lessapprox 1$ , reach could become so large cannot be observed field operations, i.e. remains hydraulically invisible. Finally, poroelasticity significantly affects response system, increasing delaying which takes place.