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Abstract As a pivotal resource for China's energy restructuring and low-carbon transition, shale gas necessitates advanced geoengineering integration for efficient development in complex structural regions. In the Luzhou region of the Sichuan Basin, deep shale gas horizontal wells at depths over 3,500 meters have experienced casing deformation issues during staged fracturing operations. This problem has significantly constrained the development efficiency of deep shale gas in this area. A multi-factor analysis was conducted on typical deep shale gas horizontal wells in the Luzhou block, further clarifying the main characteristics and causes of casing deformation. This study employs multidisciplinary integration of geomechanics, numerical simulation, and reservoir stimulation to systematically decode hydrocarbon accumulation conditions, reservoir heterogeneity, and development potential. The dynamic stress environment during hydraulic fracturing—prone to wellbore/formation damage—directly governs fracture network propagation, impacting development efficacy and post-fracturing optimization. Addressing the limitation of conventional 3D static geoengineering models in capturing stress-field evolution, we propose a novel 4D dynamic geomechanical workflow integrating laminar heterogeneity, geomechanical properties, and fracture complexity. This methodology reconstructs fracture-zone geometry, properties, and boundary conditions via finite-difference methods, establishes a fully coupled flow-geomechanics model, and combines 3D static with 4D dynamic stress fields to multi-dimensionally quantify fracturing impacts on regional stresses. Key findings reveal: (1) Fracture initiation triggers fluid infiltration, elevating pore pressure and reducing effective stress (minimum horizontal stress declining most significantly, by 18–25%); (2) Pressure propagation forms concentrated stress anomalies near wellbores, generating stress-concentration zones and pressure-depletion funnels that deflect principal stress orientations (ΔP > 8 MPa inducing 15–30° reorientation). This integrated 3D/4D geomechanical approach provides a transformative framework for optimizing shale reservoir stimulation in China's complex basins.