The activity of large rockslides is dependent on a combination of interplaying factors that control strain localization within the slope. In some cases, continued deformation may lead to widespread disaggregation of the slide mass (i.e., loss of cohesion and development of debris). Layers with markedly different composition and strength may eventually form, making it difficult to assess the actual nature of hazards and related risks posed to the valley bottom. This paper provides updated insights into the highly disaggregated and rapidly evolving Ruinon rockslide (Central Italian Alps) based on more than a decade of monitoring by means of a Ground-Based Interferometric Synthetic Aperture Radar (GBInSAR). The rockslide was recently affected by a prolonged period of exceptional surface velocities—consistently exceeding 1 m/day. Monitoring data are examined in order to estimate the thickness of the rapidly moving layer of upper chaotic debris by means of the balanced cross-section method as well as determine the effects of hydrological forcing on the slope displacements. Finite-element modelling is then used to derive hypotheses concerning the deformation behavior of the slide mass at greater depth and different elevations. It is suggested that the upper debris moves at rates several orders of magnitude higher than the underlying substrate, and that in relative terms the sensitivity to sliding of the two layers is similarly governed by the increase of piezometric levels in the spring/summer. On lower slopes, the activity of the upper debris appears to be also influenced by precipitation events that are not accompanied by a notable increase of the piezometric levels measured at the rear of the slide. Our findings show the importance of implementing long-term GBInSAR monitoring at challenging sites like Ruinon, where fieldwork and installation of instruments on the slide mass are not feasible.

大型滑坡的活动取决于控制斜坡内应变定位的相互作用因素的组合。在某些情况下，持续变形可能会导致滑动体的广泛解聚（即内聚力丧失和碎片形成）。最终可能会形成成分和强度明显不同的地层，从而难以评估危害的实际性质和对谷底构成的相关风险。本文基于十多年来通过地基干涉合成孔径雷达 (GBInSAR) 进行的监测，提供了对高度分解和快速演变的 Ruinon 岩崩（意大利中部阿尔卑斯山）的最新见解。岩石滑坡最近受到了长时间异常表面速度的影响——持续超过 1 m/天。为了通过平衡截面法估计上层混沌碎片快速移动层的厚度以及确定水文强迫对斜坡位移的影响，检查监测数据。然后使用有限元建模来推导出关于滑体在更大深度和不同高度下的变形行为的假设。这表明上层碎片的移动速率比下面的基底高几个数量级，并且相对而言，两层滑动的敏感性同样受春季/夏季测压水平增加的影响。在较低的斜坡上，上层碎片的活动似乎也受到降水事件的影响，而降水事件并没有伴随着在滑梯后部测得的测压水平显着增加。我们的研究结果表明，在 Ruinon 等具有挑战性的地点实施长期 GBInSAR 监测的重要性，在这些地点，实地工作和在滑动块上安装仪器是不可行的。