Fracture Interference and Refracturing of Horizontal Wells

Abstract

Due to fracture interference, not all perforations can be fractured, resulting in 20% of fractures contributing to 80% of the total production. The extraction of oil and gas also reduces production, necessitating refracturing. In this study, the finite element method was used to simulate multiple fractures fracturing simultaneously and the stress field distribution was then extracted and applied to a new geological model. This paper explains the effect of stress around the horizontal wellbore on new fractures during the refracturing of old wells using a temporary plugging technique. The results show that initial breaking pressures are the same, but as fractures extend, inter-fracture interference increases, resulting in different fracture extension pressures and widths. The fracturing fluid is filtered into the reservoir matrix after fracturing, reducing formation stress. Compared with fracturing at the initial fracture site, reperforating fracturing has a lower fracture extension pressure and a longer fracture length. According to this study, hydraulic fractures have a 15 m effective influence radius on the external formation. Stress relief is beneficial for fracture initiation prior to refracturing. Reperforating and fracturing, in combination with temporary plugging technology, can assist in increasing the effective stimulated reservoir volume and achieving high and stable production.