Open Access

ARTICLE

The Evaluation of Re-Fracturing Potential for Horizontal Wells in Tight Oil Reservoirs Based on Coupled Flow and Geomechanical Modeling

Huiyong Yu¹, Haifu Li¹, Liwei Zhang¹, Yong Chen¹, Rui Wang¹, Qiyong Xiong¹, Xuyang Guo², Shijie Shen^2,*
1 Production Technology Research Institute, PetroChina Xinjiang Oilfield Company, Karamay, 834000, China
2 College of Petroleum Engineering, China University of Petroleum (Beijing), Beijing, 102249, China
* Corresponding Author: Shijie Shen. Email:

Energy Engineering https://doi.org/10.32604/ee.2025.072416

Received 26 August 2025; Accepted 28 October 2025; Published online 01 December 2025

Abstract

Re-fracturing horizontal wells is a critical strategy for enhancing recovery from tight oil reservoirs, but its success depends on the evaluation of candidate wells and locations. This process is complicated by production-induced alterations in reservoir pressure and geomechanical responses. This study introduces a workflow to evaluate re-fracturing potential by integrating coupled fluid flow and geomechanical modeling for the production of initial hydraulic fractures. We developed a numerical model that simulates the poroelastic response of a tight oil reservoir to depletion from an initial set of hydraulic fractures. To quantify the re-fracturing potential along the horizontal wellbore, a novel composite re-fracturing potential index is proposed where fracture shape, stress, and pressure are considered. This index considers four key physical factors: current reservoir pressure, fracture initiation ease, fracture geometry favorability, and fracture propagation efficiency considering tortuosity. Numerical simulations were conducted for scenarios with both uniform and non-uniform initial hydraulic fractures. The results consistently demonstrate that the optimal locations for re-fracturing are the midpoints between existing fractures, where a favorable balance of high reservoir pressure and altered stress conditions exists. The analysis reveals that the overall re-fracturing potential tends to increase with production time, suggesting that a period of depletion can enhance the geomechanical conditions for subsequent stimulation. Furthermore, a sensitivity analysis on the index weighting factors shows that the optimum re-fracturing strategy is highly dependent on the primary field objective, whether it is maximizing resource contact, ensuring geomechanical feasibility, or avoiding operational complexity. The study concludes that heterogeneity in the initial fracture network creates complex and asymmetric potential profiles, which implies the necessity of case-specific and integrated analysis over simplified assumptions. The proposed methodology provides a framework for optimizing re-fracturing designs in tight oil reservoirs.

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Keywords

Tight oil reservoirs; re-fracturing horizontal wells; hydraulic fracture; geomechanical modeling; initial fracture

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