## 4 Discussion  
Through model construction and numerical analysis, this study demonstrates the critical influence of spatial variability in jointed rock masses on slope stability. The findings reveal that incorporating spatially heterogeneous parameters enables a more accurate representation of the geological characteristics. Quantitatively, the heterogeneous parameter fields exhibit substantial dispersion: for example, the rock mass elastic modulus shows a mean of 1.05 GPa and a coefficient of variation of 0.84; the Hoek-Brown-derived equivalent cohesion shows a mean of 320.71 kPa and a coefficient of variation of 0.37. In addition, the parameter block model exhibits depth-dependent increases in both the elastic modulus and equivalent cohesion, indicating the superior quality and minimal disturbance in the deeper rock strata. This trend can be interpreted from two perspectives. Firstly, it mirrors the actual geological conditions: rock masses at shallower depths are more vulnerable to weathering and fragmentation, whereas deeper rock formations generally maintain greater integrity. Therefore, deeper intervals in geotechnical borehole records typically display higher RQD and GSI values, inherently leading to higher estimated rock mass strength parameters. Secondly, this observed trend is closely linked to the modeling methodology employed. In this study, the equivalent cohesion derived from the generalized Hoek-Brown criterion is intrinsically pressure-dependent. When these Hoek-Brown parameters are transformed into the Mohr-Coulomb framework, the elevated confining pressure at depth tends to amplify the computed equivalent cohesion. This phenomenon potentially results in an overestimation of the in situ rock strength within deeper zones. In contrast, zones with weaker lithology possess intrinsically lower \(\sigma_{ci}\), \(m_{i}\), and \(J\)_Cond\({}_{89}\)_ values that, when fed into the generalized Hoek-Brown criterion, yield reduced mechanical strength; therefore, a thorough geological investigation is the indispensable foundation for a reliable mechanical characterization and slope stability calculations. The stability analysis establishes a strong correlation between the calculated safety factor distributions and actual landslide occurrences. Notably, the severely faulted zones in the southern slope precisely correspond to regions with low safety factors, aligning with areas known to be prone to landslides. This agreement confirms the reliability of our heterogeneous parameter model and analytical methodology for predicting potential instability zones. A quantitative overlay of the unstable region predicted by the heterogeneous analysis onto the mapped 2020 landslide extent reveals that roughly 75% of the observed failure area coincides with the model-identified high-risk zone. Conversely, the homogeneous parameter simulation--which omits spatial variability--produces systematically higher factors of safety, with its 25 th percentile value exceeding that of the heterogeneous model by more than 0.1 in absolute Fs units, and achieves only about 30% recall in delineating the unstable area, thereby failing to capture many hazardous zones. This discrepancy leads to a persistent overestimation of slope stability and highlights the critical need to account for spatial variability in stability assessments. The theoretical significance of this study stems from integrating spatial variability characterization of rock mass parameters with a slope stability analysis. By incorporating the Ordinary Kriging estimation and the generalized Hoek-Brown criterion into the slope mechanical analysis, this research advances knowledge regarding jointed rock mass stability. Regarding its engineering applications, the developed spatial model of mechanical parameters and rapid stability evaluation method can be directly implemented in mine slope design, monitoring, and early-warning systems. The identification of potential instability zones can enable targeted reinforcement strategies, thereby enhancing slope safety.