This contribution deals with the focusing and time–depth conversion of GPR data in a two-layer scenario. In a layered scenario, the different propagation velocities of the electromagnetic waves in different layers can induce distortion in the reconstruction. In particular, it is not possible, with common data processing, to achieve the focusing of both the targets embedded in the upper and deeper layers at the same time. We will present a strategy for mitigating this problem. The strength points of this strategy are its simplicity and the fact that it only requires a commercial code for the GPR data processing plus some steps easily implementable through a homemade code. This work extends a contribution of the same authors at the 20th International GPR conference held in Chanchung, China, in June 2024, and the conclusions are updated with three-dimensional numerical results, including depth slices determined directly in the spatial domain. Both numerical and experimental data will be shown.

How can the interaction between the seismological community and society contribute to the exploitation and usage of renewable energy resources? We try to provide an answer by describing the seismic experiment realized in March–April 2025 in the hydrothermal area close to Contursi Terme municipality (Southern Italy). We deployed a 29-station seismic array thanks to the availability of local citizens, civic administrations, schools, and accommodation facilities, which provided hosting and power for six-component seismological instruments over a one-month period. By computing the Probabilistic Power Spectral Densities (PPSD) and spectrograms, we assessed the noise level and the quality of the dataset. The seismic recordings were also used for studying the local seismic response of the area by the HVSR method and detecting small magnitude (1.4–4.2) local and regional earthquakes. We thus described some solutions to tackle the challenges of a possible geothermal exploitation project in the area: (a) to map the energy resource through a tomography on good-quality ambient-noise data; (b) to manage the seismic risk related to the resource exploitation by installing a proper local seismic network; (c) to increase the acceptance by the population through a citizen-science action for instituting a fruitful alliance between different actors of civil society.

Earthen levees represent one of the most common structural measures used to reduce the severe effects of flood events. The hydraulic risk assessment on the flood-prone areas is typically achieved by assuming the levee system undamaged during floods, but the levees can fail due to different collapse mechanisms, among which overtopping and seepage/piping, due to infiltration process through the levee body and foundation, are the most frequent.The monitoring of the levee status through techniques such as geophysical methods is fundamental to gather data for levee vulnerability analysis and to evaluate in real-time the possible happening of a breach formation.In this context, this study describes a practical procedure for assessing levee vulnerability to seepage and an experimental monitoring system to be developed for an earthen levee along the Tatarena stream, located in the Umbria Region, central Italy. The selected area was damaged in 2020 by a levee failure due to the presence of animal burrows.The monitoring system is based on combined geophysical methods: Electrical Resistivity Tomography (ERT), Ground Penetrating Radar (GPR) and Frequency Domain Electromagnetic Methods (FDEM). These methods collect different geophysical parameters (i.e. electrical conductivity and permittivity) that are correlated to the main hydraulic characteristics of the investigated subsoil, such as porosity, water content, permeability. Therefore, the geophysical methods could provide useful information on water infiltration process, making it possible to check the hydraulic status of the levees that is fundamental to identify possible critical conditions.The work was carried out in two steps: 1) levee characterization; 2) monitoring system design and implementation.First, the levee (approximately 570 m long) was analyzed using GPR, FDEM and ERT methods. The GPR (Dual-frequency antenna 300-800MhZ) was acquired by running profiles approximately 50 m long, defining a high-resolution image up to 2.0 m deep, while the electromagnetic method (Profiler EMP-400) through a continuous profile. The ERT is long 320m and a multichannel system with 72 electrodes (Syscal Pro instrument) and an electrode spacing of 1m was used. Therefore, an optimized roll – along protocol allowed to acquire a series of profiles (n.10) with 24 shift electrodes approach. All acquired data were elaborated and inverted (ZondRes2D software) to obtain the final electrical resistivity image. All the geophysical results highlighted an integrated interpretation allowing to define the characteristics of the levee and to optimally design the monitoring system.Second, a monitoring system has been designed. It comprises a longitudinal ERT, consisting of 96 electrodes spaced 0.5 m (total length of 47.5 m). Cross-sectional ERTs are planned to be placed along two sections, located 19 m and 28.5 m from the beginning of the longitudinal ERT, consisting of 24 electrodes spaced 0.5 m (total length of 11.5 m).In addition, a continuous self-potential measurement system is foreseen based on 40 electrodes located at a mean distance of 1.5 m (total system length 60 m).The data recorded during the monitoring period will be used to assess the reliability of the estimate derived through the practical procedure.

This work describes first activities carried out in the frame of WP7-7.4 task of the ITINERIS “Italian Integrated Environmental Research Infrastructures System” project (PNRR M4C2 Inv.3.1 IR), financed by European Union – Next Generation EU.An innovative integrated geophysical approach for geohazard evaluation in urban areas has been proposed with the aim of providing scientific and open digital data of multi-scale and multi-resolution near-surface geophysical observations to the scientific community, practitioners, and decision-makers according to the Digital Earth concept. This will be achieved by: a) acquiring cutting-edge geophysical equipment suites to enhance the existing ones; b) establishing a service aimed at integrating the data from a variety of geophysical sensors; c) investing in the next-generation technologies and enabling FAIR data access.One of the three pilot sites of this project is the Basilicata region (southern Italy), that is a predominantly mountainous zone affected by high seismic and hydrogeological risks. Therefore, it is well-suited to test and integrate the different geophysical methodologies, with particular attention to the seismic and electromagnetic methods. Geophysical data collected by each experiment will be integrated into the ICT project platform and made available to the scientific community.In detail, a part of Activity 7.4 focuses on the innovative use of the ERT method as an advanced observing system, able to describe the spatio-temporal changes of the resistivity patterns within the depth range 0-1 km. Preliminary tests have been conducted in some urban areas affected by landslide phenomena. The planned activity will also leverage machine learning technologies for geophysical data processing and analysis.Another action aims at enhancing the suitability of geophysical infrastructures for the characterization of urban areas, specifically for seismic risk mitigation purposes. Great attention is placed on the characterization of the urban subsoil, the overlying-built environment, and their mutual interaction to identify areas of cities where the possible resonance effect between the soil and the built environment during earthquakes may cause increased damage; this aspect is being studied and evaluated for the city of Potenza (southern Italy).The last part of the activity is devoted to designing an experiment aimed at integrating DAS measurements (to be carried out using a 4 km long fiber-optic cable already installed in the industrial area of Tito, located close to the urban area of Potenza), ERT surveys, and seismic array data for a multi-parametric characterization of the near surface and monitoring its changes over time. This will offer unique opportunities for the scientific community to test and improve different methods in a controlled environment, while also assessing the effectiveness of monitoring the near-surface through DAS-recorded ambient noise.

Transportation networks rely heavily on bridges whose safe operation depends on maintaining structural soundness. Natural phenomena, such as landslides and human-induced incidents, pose significant threats to bridges, with consequences ranging from compromised safety to complete failure and service interruption. Multiple variables determine the extent of structural deterioration, including the nature of hazardous events, material composition, and existing maintenance conditions. A comprehensive evaluation of landslide-related threats necessitates examining a variety of factors, including the geophysical properties of the subsoil and an in-depth knowledge of the bridge key structural elements, such as its foundations, piers, and abutments, as well as their current state of conservation.Supported by the FABRE consortium, the EMILI project - ElectroMagnetic techniques for Investigating Landslide and structural damages due to their Impacts on bridges - aims to establish uniform protocols and operational frameworks for electromagnetic investigation techniques in bridge-landslide hazard evaluation. By targeting Electrical Resistivity Tomography (ERT) and Ground Penetrating Radar (GPR), EMILI advances the standardization, reliability, and field implementation of electromagnetic approaches.Initial findings from EMILI are discussed here, encompassing two primary contributions. The first concerns a comprehensive literature analysis examining both capabilities and constraints of ERT and GPR in field applications involving bridges, landslides, and their interactions. The second deals with preliminary results from simplified numerical models exploring the detection potential of ERT and GPR when applied via conventional and unconventional measurement configurations. Specifically, surface and borehole data from simulated scenarios involving diverse lithologies, foundations, and water content are considered and processed to establish the potential and limitations of ERT and GPR in estimating the shape and depth of the foundation piles.Preliminary synthetic results are promising and demonstrate the capability of ERT and GPR to identify foundation structures in simplified geological contexts.

This work is supported by the projects TOGETHER – Sustainable geothermal energy for two Southern Italy regions: geophysical resource evaluation and public awareness (https://www.together-prin.it/) and ITINERIS – Italian Integrated Environmental Research Infrastructures System (https://itineris.cnr.it/), funded by the European Union – Next Generation EU (PNRR, M4C2, Investments 1.1 and 3.1, respectively).As part of the ITINERIS project, the geophysical laboratory of CNR-IMAA was upgraded with advanced geophysical instrumentation characterized by lower operational costs, increased flexibility, higher sensitivity, and faster acquisition rates. The availability of dense and flexibly deployable geophysical sensors significantly improves survey resolution, particularly in complex urban and semi-urban environments, thereby supporting sustainable and resilient urban development.Under the TOGETHER project, the upgraded instrumentation was tested at pilot sites, including the Sele River Valley (SRV) in the Campania region (Southern Italy). This area hosts numerous thermal springs and wells with temperatures reaching up to 48 °C, currently used for spa and therapeutic purposes. These characteristics make the SRV a natural laboratory for testing integrated geophysical approaches aimed at identifying geothermal targets in proximity to existing communities and infrastructure.Geothermal energy, particularly low- to medium-enthalpy systems, represents a key renewable resource for the energy transition, enabling the sustainable exploitation of local resources, the reduction of greenhouse gas emissions, and the strengthening of regional energy resilience. Integrated geophysical investigations play a crucial role in reducing exploration uncertainty and promoting environmentally responsible geothermal development.In the SRV area, geophysical surveys were conducted over a target zone of approximately 6 × 8 km², centered on the hottest thermal manifestations. A comprehensive geophysical dataset was successfully acquired in a challenging urban and semi-urban context characterized by logistical constraints and high levels of anthropogenic noise. Multi-scale and multi-resolution three-dimensional subsurface electrical resistivity models were derived using shallow and deep Electrical Resistivity Tomography (ERT/DERT) and Magnetotelluric (MT) surveys. In parallel, ambient seismic noise recordings were acquired and processed using single-station HVSR analyses and array-based Ambient Noise Tomography (ANT).In parallel with fieldwork, public engagement activities were implemented to foster trust and collaboration with local stakeholders. These activities included the involvement of high school students and teachers, communication through municipal social media channels, the distribution of participation certificates, and the organization of a final dissemination event aimed at citizens, local institutions, schools, and stakeholders. The event was dedicated to sharing the results and research activities developed in the area as part of the TOGETHER project, with a particular focus on energy sustainability and the enhancement of local geothermal resources, also through direct dialogue between researchers and the public. These initiatives proved essential for ensuring transparency, site accessibility, and awareness of local geothermal potential.The results demonstrate the feasibility and effectiveness of an integrated geophysical and participatory approach, highlighting the importance of public engagement and standardized workflows for sensor deployment and data processing.