Coupled Wellbore-Reservoir-Geomechanics Modeling of Parent Well Depletion-Induced Stress Evolutions and Their Potential Impact on Infill Well Fracturing

Parent well depletion in shale oil reservoirs leads to in-situ stress changes, consequently altering infill well fracturing quality. Parent well depletion-induced responses are often modeled by coupled flow and geomechanics where the effect of wellbore flow is not thoroughly considered. This study introduces a coupled wellbore-reservoir-geomechanics model considering the wellbore flow. Both system responses in the reservoir and in the wellbore are quantified. Results show that considering the wellbore flow can improve the comprehensiveness of the modeling scheme. The non-uniform productivity distribution among perforations and its relationship with the coupled flow and geomechanical response are documented. The effect of wellbore flow becomes greater as the scale of the problem increases, and the synthetic field scenario has a more significant wellbore flow impact on geomechanics. This work proposes a coupled wellbore-reservoir-geomechanics model that considers the mass conservation and fluid flow in both the wellbore and the reservoir. It specifically quantifies the effect of the oil rate competition between parent well fracture clusters. 1. INTRODUCTION Infill well drilling and hydraulic fracturing have become a key strategy in the development of shale oil reservoirs since the combination of parent and infill wells can help to improve the estimated ultimate recovery (Lindsay et al. 2018). Infill wells are often drilled and completed later than parent wells, and the pressure and in-situ stress fields for infill wells fracturing can be rather different from parent wells. Since the hydraulic fracturing quality is often governed by the pressure and stress states, the reliable and accurate prediction and modeling of the stress state changes in infill zones and at candidate infill well drilling locations become very relevant (Kurtoglu and Salman 2015; Zhi et al. 2021 Chen et al. 2021). Pressure drops, stress magnitude changes, and stress orientation changes in infill zones should all be evaluated before infill well completion designs are made. If infill well fracturing parameters are not carefully determined, negative outcomes such as productivity decrease, well control problems, casing damage, and loss of wells can be obtained (Morales et al. 2016; Jacobs 2017; Rainbolt and Esco 2018).