The Influence of Peri-wellbore Stress and Seepage Fields on Adjacent Faults

Summary Faults are a common type of geological structure, widely found in areas with active tectonic development. Fault zones may be accompanied by a large number of fractures, which are conducive to the formation of complex fracture networks in oil and gas development. However, faults also exhibit characteristics of low strength and susceptibility to deformation. Due to excavation and seepage effects, there are wellbore surrounding stress field and seepage stress fields near horizontal wells. To clarify the influence of the wellbore surrounding stress field and seepage stress field on the near-wellbore faults, this study established two different physical models, derived general theoretical formulas for the near-wellbore faults under the influence of the wellbore surrounding stress field and seepage field, and combined this with the basic fault activation theory based on the Mohr-Coulomb criterion. The study also defined the regional activation rate, analyzed the activation risk of near-wellbore faults under the influence of the two stress fields, and designed orthogonal experiments to study the influencing factors. This research provides certain reference significance for optimizing the selection of horizontal well locations.