The most important factors governing hydraulic fracture propagation are completions and treatment design, in-situ stresses, and reservoir heterogeneity at different length scales (including natural fractures and bedding planes). However, it has been recognized that in depleted reservoirs, stress changes arising due to reservoir drainage significantly affect the growth of fractures and attract them towards the depleted regions.

Using a poroelastic hydraulic fracturing simulator based on the theory of peridynamics, stress reorientation due to production and its sensitivity on Biot’s constant, pressure drawdown and reservoir fluid type is studied. It is shown that a tensile region is created between the fractures of a producing parent well. Consistent with previous studies, it is verified that a fracture from a newly drilled child well grows asymmetrically towards the depleted regions. When the child well lateral is not landed centrally between the parent wells and there is unequal depletion of these wells, asymmetry in the geometry of the child well fracture may further be accentuated. Similar observations can be made when production is from a gas reservoir. This asymmetric fracture growth leads to parts of the undepleted reservoir remaining unstimulated. Re-pressurization of the parent well fractures is shown to revert the stress state closer to the in-situ conditions, thereby reducing the attraction of the child well fracture towards depleted regions resulting in a better stimulation treatment.