In the present paper we have reconstructed the geologic substrate in the area of Rome comprised between the Capitoline Hill and the Colosseum. The analysis of the stratigraphic logs of a large number of boreholes allowed us to highlight the occurrence of a buried fluvial channel of the Paleo- Tiber River, the geometry of which mimics, almost exactly, the fluvial bend hosting the present-day Tiber Island. Several 40Ar/39Ar dates allowed at discriminating two aggradational successions filling this paleo-channel, deposited during two consecutive glacio-eustatic cycles corresponding to Glacial Termination VIII (621 ka) and VII (534 ka). The buried paleo-channel corresponds with a partially obliterated NW-SE morpho-structural lineament affecting the present morphology, parallel to another, more marked lineament, hosting a tributary valley of the Tiber River, the Murcia Valley, 1 km to the southwest. Such lineaments match with the direction of the main Pleistocene extensional faults on the Tyrrhenian Sea margin of central Italy, which are re-activated under the present-day tectonic regime, exerting a close structural control on the drainage network of the Tiber River catchment in the area of Rome. The activity of one of these faults, running along the Murcia Valley, has been recognized to be responsible for the diversion of the Tiber course and the birth of the Tiber Island during the 6th century BCE. We conclude that a long-lasting structural control existed on this portion of the Tiber valley, which caused the repeated diversion of the river channel, around 650 ka and 550 ka, and ultimately in the 6th century BCE, creating the conditions for the origin of a fluvial island in correspondence with the fault-controlled river bend.

This study employs an integrated geophysical approach, combining Electrical Resistivity Tomography (ERT) with Dipole-Dipole, Pole-Dipole, and Pole-Pole arrays and Vertical Electrical Sounding (VES) with a Schlumberger array, to delineate groundwater resources in the municipality of Sucupira do Norte, Maranhão, Brazil, a region with water scarcity. The survey successfully identified three aquifer units: a shallow unconfined aquifer (<35 m depth; 10 to 100 Ω∙m) considered unsuitable for use due to the risk of contamination, and two deeper confined aquifers. Aquifer B was identified at depths of 60 to 90 m, with resistivity values of 500 to 600 Ω∙m, while the main target, Aquifer C, was found at depths of 140 to 190 m, with lower resistivity values of 50 to 100 Ω∙m, indicative of water-saturated sandstones within the Pedra de Fogo Formation. Based on these results, two specific drilling locations were defined, with recommended depths of 160 m and 270 m to ensure sustainable production. The results demonstrate the effectiveness of integrating Electrical Resistivity Tomography (ERT) and Vertical Electrical Sounding (VES) to reduce uncertainty in exploration and provide a robust strategy for the sustainable management of groundwater in drought-prone regions.

Santorini Island is of volcanic origin and has historically faced repeated volcanic and seismic activity. In early 2025, increased volcanism and intensified earthquake activity, similar to 2011-2012, caused residents’ concern. This study aims to characterize ground deformation on Santorini Island during its volcanic unrest in 2025 using InSAR observations. For this purpose, 74 synthetic aperture radar (SAR) images of Sentinel-1A satellites in descending and ascending orbits were acquired from early January 2024 to late March 2025. Line-Of-Sight (LOS) velocity values of the descending and ascending orbits were decomposed to determine the east-west and vertical displacement velocities. According to the results obtained, uplifts up to +60 mm/year velocity values were detected in the central parts of the island called Caldera, and subsidence up to –30 mm/year velocity values were detected in the outer regions. In addition, eastward horizontal movements reaching velocities of +60 mm/year and westward horizontal movements reaching velocities of –50 mm/year were also detected throughout the island. In the second stage of the study, a total of 4 points were selected on the islands of Thira, Thirasia, Nea Kameni, and Palea Kameni, considering the Kameni and Kolumbo fault zones. For these points on the island of Santorini, the displacements occurring over 15 months were analysed by time series analysis, and the temporal behaviour of the deformation (increasing/decreasing trend) was monitored. The analysed data indicate that the ongoing horizontal and vertical movements on the island could be caused by volcanic rather than seismic effects, which is consistent with previous studies. This situation shows that volcanic risk assessments in the region should be monitored for the upcoming processes.

In early‑stage exploration for minerals, hydrocarbons, and geothermal resources, potential geophysical methods such as Gravity and Geomagnetic surveys stand out for their efficiency, rapid data acquisition, and cost‑effectiveness. Despite their advantages, the interpretation of data derived from these methods is often challenged by the non‑uniqueness of the solution, leading to potential biases in the subsurface models without the support of additional geological or geophysical data. Our study was initiated by developing forward models based on synthetic gravity and magnetic data configured for volcanic terrains anomaly scenarios. This approach facilitates the evaluation of inversion algorithms to mitigate the inherent non‑uniqueness of potential method‑derived models. The main objective of our research is to integrate comprehensive regional geological knowledge, which significantly enhances the accuracy of subsurface interpretations when combined with advanced geophysical techniques. This synergy is further exemplified by applying an Lp‑Norm fast 3D cross‑gradient joint inversion strategy, leveraging gravity and magnetic data to optimize computational efficiency while refining anomaly delineation. Notably, our strategy incorporates a hexahedral terrain model to account for gravitational and magnetic effects of complex terrain, marking a significant advancement in the field. Our findings demonstrate that a nuanced understanding of geological conditions, when integrated with a robust geophysical framework, can lead to the successful reconstruction of volcanic complex subsurface models. This breakthrough has profound implications for geothermal exploration, mineral exploration, and volcanic studies, offering a novel pathway toward more accurate subsurface exploration techniques.

Gravity is a force contributing to the strain energy and the tectonic stress driving faulting and generating earthquakes. This paper discusses the role of gravity in earthquake mechanics for different tectonic settings. Considering the stress state in normal and reverse tectonic settings, including gravity as a direct contribution to lithostatic load, it is possible to show that earthquakes on normal faults do not have a different energy source than elastic rebound and that this explains differences with reverse faulting earthquakes. The paper discusses the implications from dismissing the elastic rebound theory or limiting its validity to reverse or strike‑slip faulting, as suggested to support the graviquakes model, and the consequences on the mechanics of dip‑slip earthquakes. A simple model of tectonic stress relying on Anderson theory of faulting can describe the different stress state of normal and reverse faulting earthquakes, showing higher values of tectonic stress acting on reverse faults than normal faults, for different values of the static friction coefficient. The model shows that the difference between tectonic stress before and after a dip‑slip earthquake increases with the static friction coefficient, emphasizing the effect of the drained conditions on compressional tectonic stress, and the negligible effect for extensional tectonic settings. Slip can occur on normal faults creating horizontal extensional deformation when the minimum stress is compressional, since extension is caused by the deviatoric stress acting on the fault plane. The different stress state can explain numerous seismological observations, likely accounting for non‑Byerlee friction, stress and strength heterogeneity and geometrical complexity. The adoption of elastic rebound does not imply that the energetics of normal and reverse faulting earthquakes is the same. Considering crustal faults as passive subjects accommodating slip caused by volume collapse contradicts geological observations of fault zone structure, laboratory experiments and the spectrum of fault slip behavior. Faults are active geological subjects characterizing the strain localization and the energy release.

In many countries, the subsurface is increasingly recognized as an integral part to urban planning, requiring detailed knowledge of the 3D subsurface geometry and properties of both natural sediments and artificial deposits. The underground data are essential for visualizing and analyzing geological features in combination with artificial structures, assessing risks related to groundwater protection, seismic hazard, and preserving archaeological heritage. Geographic information systems offer powerful tools for managing and visualizing spatial data, facilitating the creation of detailed subsurface models. In this work, a novel geo‑lithologic database has been implemented in a GIS environment to provide a comprehensive understanding of the subsurface of the Roman urban area. The Roman area, despite being located in a moderate seismic hazard zone, is exposed to a significant level of seismic risk, also due to the unique cultural heritage of its historical center. Over 800 boreholes, with average depths of 50‑60 m, were georeferenced and interpreted from a large database of civil engineering boreholes. This geodatabase (hereafter GDB) served as the basis for developing a 3D subsurface model, finalised to seismic response analyses in the framework of the INGV Dynamic Planet ST‑Predict project. In addition, the development of an implicit 3D geological model for Rome, based on stratigraphic correlations and lithofacies analysis, provides crucial input for future analyses on the Quaternary deposits of the Roman area.

This study analyzed the stress transfer and the aftershock distribution in the Thailand-Laos-Myanmar border. The fault parameters of the three strong earthquakes with M ≥ 6.0 that occurred during 2010-2022 in the Thailand-Laos-Myanmar border were used to calculate the Coulomb stress change with the numerical modeling techniques resolved on the receiver fault with i) focal mechanism similar to the mainshock, ii) strike-slip, iii) thrust, and iv) normal faulting, respectively. The earthquake events were declustered spatially and temporally to identify the aftershocks in the area. Then, the stress transfer and aftershock distribution were analyzed to investigate the relationship. The results indicated that the type of receiver fault was the important factor that influenced the pattern of stress transfer on the Thailand-Laos-Myanmar border. The M6.1 earthquake in 2014 in Thailand generated most aftershocks in the areas of increased stress with stress change levels of more than 0.8 bar. The M6.9 earthquake in 2011 in Myanmar caused the stress to transfer into Thailand with increased stress levels smaller than 0.3 bar, and there was no aftershock generated in this area of Thailand. Meanwhile, the M6.2 earthquake in 2019 in Laos induced stress transferred into Thailand with levels of increased stress up to 0.8 bar, and there was one aftershock generated around this area of Thailand. The results are likely to be the characteristic of stress transfer and aftershock distribution, especially with increased stress levels above 0.8 bar, which can be used to identify the areas of aftershocks after the strong earthquake occurred in the Thailand-Laos-Myanmar border.

The northern extension of the AdriaArray, a dense network of broadband seismic stations, covers the southeastern part of the Bohemian Massif, the Eastern Alps, the Western Carpathians, and the northernmost part of the Pannonian Basin. Considering also the previous passive experiments carried out since 2015, the existing 32 broadband permanent stations have been complemented by 89 temporary stations deployed in the collaborative effort of institutions from the Czech Republic, Poland, Austria, and Slovakia. We document the seismic station configuration, instrumental equipment, data transmission, preprocessing, and availability, as well as the general organization of the network. Since spring 2022, when the AdriaArray network started its operation, to January 2025, approximately 2.8 TB of data recorded by the temporary stations has been transmitted to the European Integrated Data Archive (EIDA), with an average completeness of 80% and real‑time operation for 91% of the stations. The network records valuable data for a wide range of Earth science studies, including earthquake location, seismic hazard assessment, and high-resolution images of the crust and upper mantle structure. As examples of data utilization, we show Moho depth variations from the Bohemian Massif to the West Carpathians and the northernmost part of the Pannonian Basin, as well as prevailing NW‑SE polarization azimuths of the fast shear waves from the splitting evaluations at stations in the broader surroundings of the Carpathians.

Malta lies in a seismically active region of the Central Mediterranean, where local and distant earthquakes pose a hazard to the local community. To address this, the Malta Seismic Network (MSN) was established, growing from three to eight stations over the past decade. This study reviews the performance and data quality of the MSN, assessing availability, noise levels, timing accuracy, and sensor orientation. Results show generally reliable operation, though a few individual stations faced challenges such as power shortages, equipment failures, and timing inconsistencies. The network has proven crucial during seismic crises and of benefit for geophysical investigations. Future developments aim to expand the station coverage and strengthen international collaborations, ensuring the MSN continues to advance earthquake monitoring and geophysical research in Malta and beyond.

We present the deployment and performance of 17 temporary broadband seismic stations installed in Northern Italy and Sardinia as part of the AdriaArray project. These stations aim to densify the national seismic network, especially in areas with historically sparse coverage such as the Po Plain and Sardinia. We describe here the network design and site selection that follow high‑quality standards developed during previous large‑scale European seismic experiments. Despite challenging environmental and anthropogenic conditions, the stations recorded high‑quality data, enabling both local and teleseismic event detection. We analyze the seismic noise characteristics across the network using probabilistic power spectral densities and observe that stations installed in sedimentary basins typically show higher noise levels at short periods, while stations in rock sites – especially in Sardinia – generally perform better. The use of different sensor types and installation methods also influences noise behavior, particularly in the long‑period components. Despite the diverse conditions, the stations allow for the recording of both local and teleseismic events. The addition of the 4P stations improves the network’s detection threshold by approximately 0.4 magnitude units in Sardinia and 0.2 in the North Italy. The open‑access data from this deployment contribute to AdriaArray’s broader goals of advancing seismic imaging and geodynamic interpretation in the Mediterranean region.