Reduced production from child wells has been observed due to prior depletion around the parent well. In this work, a systematic simulation study is conducted to understand the effects of parent well depletion on child well fracture growth and production.
A three-dimensional hydraulic fracturing simulator based on the displacement discontinuity method is used to simulate parent well fracturing. The created hydraulic fractures are transferred into a finite volume-based geomechanical reservoir simulator for production simulation. The pressure and stress profiles in the reservoir after production simulation are then used in the hydraulic fracturing simulator to capture the effect of depletion on child well fracturing. Infill timing (parent well production duration before child well stimulation) is varied, and its impact on child well fracture geometry and the production (from the child and parent wells) is investigated.
The depletion of the reservoir due to production from the parent well can have a significant effect on the child well fracture growth. Asymmetric fracture growth, the tendency of the fractures to grow towards the depleted region, is clearly observed. The effect of the extent of depletion (infill timing) on asymmetric fracture growth for different reservoir diffusivities () is quantified. The impact of child well fracturing on the parent well production is explored for different operating scenarios. The effect of well spacing on parent-child well interactions is also analyzed. This work provides quantitative estimates of the impact of depletion on the fracture geometry, and productivity.