## 6 Discussion  
The study presented herein offers valuable insights into the anchoring effect of abandoned oil wells on the stability of overburden within coal, oil, and gas co-production zones. The integration of mechanical modeling with numerical simulations forms a robust framework for understanding the influence of wellbore infrastructure on the stability of surrounding rock. Consequently, the findings significantly enhance our understanding of both the mechanical interactions between oil well casings and surrounding rock formations, as well as the broader implications for geotechnical stability in multi-resource extraction zones. 1. The anchoring effect induced by oil well casings plays a crucial role in stabilizing the overburden above oil and gas reservoirs [31]. The results of this study demonstrate that oil well casings, particularly those penetrating coal seams, substantially alter the stress distribution within the surrounding strata. As the burial depth of oil wells increases, the mechanical benefits of casing anchorage become more pronounced. Mechanical parameters such as cohesion, internal friction angle, and compressive strength are all enhanced by the anchoring effect, thereby reinforcing the integrity of the overburden and mitigating the risk of subsidence and fracture propagation. The results of numerical modeling clearly illustrate how oil well anchoring reduces subsidence in the near-wellbore region, offering vital protection against overburden damage. Notably, the depth-dependent expansion of stress concentration zones and the displacement influence range provide key insights into how anchoring can regulate stress distribution in the subsurface. These findings emphasize the importance of wellbore design, particularly in deeper burial zones where stress concentration becomes more localized and the potential for wellbore destabilization increases. 2. One of the most important findings of this study is the significant role that anchoring plays in redistributing subsurface stresses. The mechanical model of the study effectively illustrates how casing systems, through their interaction with surrounding rock, prevent excessive deformation in the overburden, particularly in high-stress environments. By creating a stable support structure within the geological strata, anchoring mechanisms reduce the likelihood of rock slippage and wellbore collapse--risks commonly associated with complex multi-layer formations, such as coal seams and high-pressure gas reservoirs [32]. The results of this study complement earlier works by expanding the focus to include oil and gas co-production zones, which are increasingly prevalent in global resource extraction strategies. The integration of casing and cementing systems in this study enhances rock cohesion and shear strength, providing a detailed quantitative basis for understanding how wellbore infrastructure can modulate the stress and strain fields in the surrounding strata. 3. The theoretical analysis of casing and cementing systems, coupled with the results of numerical simulations, provides critical practical implications for the design of oil and gas extraction operations in coal, oil, and gas co-production zones. The ability to predict and manage overburden stability using anchoring technology will allow engineers to devise more effective strategies for wellbore construction, maintenance, and abandonment. Particularly in regions where resources are located at considerable depths, such as the Yan'an coal mines in China, the anchoring effect offers a viable method for enhancing wellbore stability and preventing catastrophic failures during both drilling and production. Furthermore, the reduction in formation subsidence observed in the study underscores the potential for anchoring systems to mitigate the environmental impact of resource extraction.