Abstract Large earth slides and rocks lides evolving into earth flows are quite widespread in the Northern Italian Apennines. Despite being simply referred to as landslides, many of them are, in fact, large complexes of landslides. They evolved through multiple and/or successive movements, undergoing partial and/or total reactivations. The reactivation of pre-existing landslide bodies is the prevalent mechanism for the known landslide events, as the historical records and the technical reports indicate. Landslide reactivation is, indeed, a relevant topic from the perspective of risk assessment and mitigation. A multi-parameter monitoring system was installed on a large complex of landslides that underwent partial or total reactivations after heavy rainfall events, causing damages to buildings and infrastructures. Two clusters of automatic piezometers—each coupled with an inclinometer—and a time-lapse resistivity deployment were the core of the monitoring system. A weather station, collecting data from subsurface thermometers, and a water content probe completed the system. After the construction of a new geological model of the slope, this study aimed at understanding the possible mechanisms leading to the reactivation of the landslide. This goal was achieved by gaining insights into the process of rainfall infiltration into the landslide deposits, by determining the groundwater flow and evaluating the landslide displacements. The monitoring system captured the processes that took place in the landslide bodies and the bedrock in response to a rainfall event in early February 2017, which followed a dry period of eight months. The recorded data provided indications on the variation of the hydraulic head in the groundwater within the landslide and the bedrock, particularly at the sliding surfaces. The electrical conductivity of the groundwater and the resistivity of the terrain varied across the failure surfaces. In particular, a sudden increase in the electrical conductivity was related to the locations of the main sliding surfaces. The joint analysis of time-lapse resistivity, hydraulic heads, and groundwater electrical conductivity helped identify the locations of weaker levels within the landslide masses, which were confirmed by data from inclinometers. This study improved the knowledge of the hydrogeological behaviour of a complex of landslides in heterogeneous low-permeability media. Moreover, the obtained results contributed to the understanding of the role played by different portions of the landslide complex in the evolution of the movement.

中文翻译：

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一个多参数现场监测系统，用于研究意大利北部亚平宁山脉的大型滑坡-地流动力学

摘要 在意大利北部的亚平宁山脉，大型地滑和岩石滑坡演变成地流非常普遍。尽管被简单地称为滑坡，但其中许多实际上是大型滑坡复合体。它们通过多次和/或连续运动进化，经历部分和/或全部重新激活。正如历史记录和技术报告所表明的那样，先前存在的滑坡体的重新激活是已知滑坡事件的普遍机制。从风险评估和缓解的角度来看，山体滑坡再激活确实是一个相关主题。多参数监测系统安装在大型滑坡群上，这些滑坡在暴雨事件后部分或全部重新激活，对建筑物和基础设施造成破坏。两个自动压力计集群——每个都与一个倾角计相结合——和延时电阻率部署是监测系统的核心。一个气象站，从地下温度计收集数据，以及一个含水量探测器完成了该系统。在建立新的斜坡地质模型后，本研究旨在了解导致滑坡重新激活的可能机制。通过确定地下水流量和评估滑坡位移，深入了解降雨渗入滑坡沉积物的过程，从而实现了这一目标。监测系统捕捉到了 2017 年 2 月上旬的降雨事件发生在滑坡体和基岩中的过程，该事件随后经历了 8 个月的干旱期。记录的数据提供了关于滑坡和基岩内地下水水头变化的迹象，特别是在滑动面。地下水的电导率和地形的电阻率在不同的故障表面上是不同的。特别是，电导率的突然增加与主要滑动面的位置有关。对延时电阻率、水头和地下水电导率的联合分析有助于确定滑坡体中较弱水位的位置，测斜仪的数据证实了这一点。这项研究提高了对非均质低渗透介质中滑坡复合体的水文地质行为的认识。而且，