Ocean tidal loading (OTL) induced surface displacements, driven by lunar and solar gravitational forces, present significant challenges in geodetic applications, requiring precise modeling to improve GNSS positioning accuracy. The study conducts a methodological and feasibility assessment of the differential and absolute approaches for detecting and quantifying OTL signals from GNSS coordinate time series. By analyzing GNSS data from selected stations, this research assesses the strengths and limitations of DD and PPP in estimating OTL displacements. Applying the OTL model correction reduced coordinate RMS values by up to 22 K_1 . However, diurnal constituents are particularly sensitive to GNSS-related systematic effects, including satellite orbit mismodelling and constellation repeat periods. Long baselines in DD improved detectability of differential signals but can introduce residual atmospheric biases, whereas shorter baselines were more resilient to noise yet less sensitive to weak tidal components. These results demonstrate that millimeter-level OTL displacements can be reliably detected with GNSS, but the choice of processing strategy and baseline configuration strongly influences the accuracy, resolution, and spectral completeness of the recovered tidal signals. By quantifying these effects across contrasting tidal regimes, this study provides a rigorous assessment framework that can guide the optimal use of DD and PPP in geodetic and geophysical applications.

Landslides are significant natural hazards frequently triggered by heavy rainfall and earthquakes, representing the most damaging secondary coseismic environmental effects. In geologically active regions like the Northern Apennines (Italy), high seismic hazard often couples with frequent large-scale slope failures. Global evidence suggests a complex interplay between triggers: earthquakes following intense rainfall tend to induce more landslides, while seismically impacted areas often show elevated landslide rates in subsequent years. Analyzing these tectonic-meteorological interactions is crucial for accurate hazard prediction.The central goal of this research is to resolve the intricate interactions among tectonic, meteorological, and surface processes by evaluating the role of seismicity and rainfall (whether concurrent or not) in the evolution of slope failures. This presentation details the conceptual framework and preliminary implementation of a newly initiated project aimed at monitoring these dynamics in real-time. The investigation focuses on the fundamental mechanisms of landslide induction, considering pre- and post-seismic meteorological states to identify crucial triggering parameters.The study utilizes a dedicated, multi-technique monitoring network at the Roncovetro landslide, a relatively young complex-earthflow, with a mean discharge rate of ∼ 0.16 × 105 m3/yr, that serves as a natural laboratory for landslide characterization in the Apennines. To discriminate between induction mechanisms, we integrate:Remote Sensing Tools: Repetitive Unmanned Aerial System (UAS) surveys are employed to conduct high-resolution terrain analysis and quantify volumetric changes. Comparison of digital topography (including historical 1973 data vs. 2014–2025 datasets) allows for the assessment of long-term discharge rates and morphological evolution.Ground-Based Monitoring: An already existing local network of Global Navigation Satellite System (GNSS) stations and Ultra Wide Band (UWB) sensors provides high-frequency displacement data, enabling the correlation of movement with specific triggers. New GNSS stations will be installed in different sectors of the landslides in order to extend the real time analysis of the slope movements.Meteorological Data: Continuous hydro-meteorological parameters are gathered from a nearby weather station managed by the Regione Emilia Romagna, providing the high-resolution rainfall data necessary to establish triggering thresholds.Novel Geophysical Sensing: High-resolution seismic data will be acquired through Distributed Acoustic Sensing (DAS), leveraging fiber optic cables to create a dense linear array of seismic sensors at a 1-meter spatial scale.Field Analysis: Conventional geomorphological mapping and field-based geological surveys validate the remote sensing products and ground-truth the internal boundaries of the landslide body.The availability of this integrated observational network will allow for the spatial and temporal discrimination of landslide sectors triggered by meteorological events versus those sensitive to seismic shaking. Future analysis of the Roncovetro site—an area already characterized by historical data and impacted by both significant earthquakes (e.g., the 1996 Mw 5.4 event) and recent extreme rainfall (2024–2025)—will try to highlight relationships between antecedent moisture conditions and seismic history to define slope stability. This integrated analysis is expected to provide fundamental insights into event timing, shaking intensity, and the ultimate magnitude of landslide movements. Ultimately, the project will offer a robust, multi-sensor framework for multi-hazard risk assessment in complex terrain.

Identifying seismogenic faults in offshore regions presents significant challenges, particularly in achieving their precise geometry and kinematics. Geological data derived from deep-sea exploration and geophysical surveys are commonly used to characterize offshore active faults together with earthquake hypocentral locations. However, limitations may arise in the quantity and quality of geophysical available data, inhibiting the realization of accurate 3D models. Furthermore, the precise relocation of seismic events is demanding, especially in the depth domain, due to the limited azimuthal coverage and the minimum station-event distance that is well beyond the mean depth of the events. In this context, an interdisciplinary approach becomes imperative to mitigate over-interpretation and over-simplification in defining the seismogenic sources and establishing an all-encompassing rupture model. By means of an interdisciplinary (geological, seismological, and geodetic) approach, we investigate the outermost Northern Apennines fold-and-thrust belt front in the Adriatic Sea (Italy) involved in the Costa Marchigiana Pesarese seismic sequence started with the 9 November 2022 Mw 5.5 mainshock. Given the proximity of the mainshock and the subsequent seismic sequence to the urbanized coastline, where several cities are situated, characterizing the activated faults and the related estimation of ground displacement becomes crucial for seismic risk assessment and the tsunamigenic potential. We analysed the geological setting of the area by means of an accurate interpretation of numerous seismic reflection profiles and well data acquired over the past decades, which complemented the publicly available seismic data. The interpretation of this dataset, provided by oil companies, led to an accurate definition of the thrust systems highlighting both the geometry of the activated sector of the thrust front and its relation to potentially active adjacent faults. Moreover, the results show the strong influence of past paleogeography and paleomorphology on the evolution and geometry of this sector of the fold-and-thrust belt, including the buttressing effect of carbonate platforms and inherited highs. The resulting 3D model was integrated with seismological data and geodetic observations allowing us to well highlight the activated portion of the fault plane: strong motion data and continuous GNSS stations hosted by onshore (storage centers) and offshore (seabed-anchored hydrocarbon platforms) infrastructures were jointly inverted to retrieve the Mw 5.5 coseismic rupture history.

Nowadays, information obtained through Global Navigation Satellite Systems (GNSSs) is widely employed in modern geodesy. The Precise Point Positioning (PPP) approach, which leverages signals from multiple GNSS constellations (e.g., GPS, GLONASS, Galileo, and BeiDou), enables high-precision positioning—crucial for seismic monitoring and early tsunami warning systems (EEWs). Recent advances, such as increased satellite availability and additional frequency bands, have significantly improved PPP performance, particularly in terms of positioning accuracy and convergence time. This study focuses on the Rete Integrata Nazionale GNSS (RING) network, managed by the Istituto Nazionale di Geofisica e Vulcanologia (INGV), which comprises dual-frequency GNSS receivers distributed across the Italian peninsula and parts of the Mediterranean Basin. We evaluate the performance of the RING data (GPS and GNSS) acquired in a period of three weeks between 19 January 2024 and 9 February 2024 and analyzed in real time by using different PPP strategies: standard PPP and PPP with Regional Augmentation (PPP-RA). The preliminary results show that the PPP-RA approach enhances positioning accuracy and reduces convergence time, especially when comparing GPS-only datasets with those incorporating full multi-GNSS configurations. For the daily solution, in the optimal setup (i.e., full GNSS with RA), real-time solutions exhibit average accuracies of 2.05, 1.73, and 4.35 cm for the North, East, and vertical components, respectively. Sub-daily accuracies’ analysis, using 300 s sliding windows, showed even better uncertainties, exhibiting median values of 0.41, 0.32, and 0.9 cm for the North, East and vertical components, respectively. Based on the outcomes for network-wide sub-daily accuracies, 84% of the stations demonstrate average errors within 2 cm for North and East components and 3 cm for the vertical one. The analysis on the convergence time after data gaps occurred during the investigation period shows that 87% of the RING stations experienced convergence times lower than five minutes in the GNSS PPP-RA solution. These findings underscore the potential of RT-GNSS RING data for enhancing seismic monitoring and early warning systems, particularly in tectonically active regions.

The Roncovetro landslide is a complex active earth flow located in the Enza Valley (Emilia-Romagna Region, Italy). It carves the southern flank of Monte Staffola from its summit to the riverbed of Tassobbio stream, with a total involved volume of ~ 3×106 m3. This ~ 2.5 km landslide has a maximum width of 300 m and a 30-40 m wide channel that separates the depletion zone from the accumulation zones. Since the clay fraction is largely dominant, the landslide mainly behaves like a fluid-viscous earthflow. capable of reaching maximum velocities of up to 10 m/day. The perennial activity of the Roncovetro landslide is characterized by phases during which the detachment is limited to deep creep, sliding, and flowing, as well as major events that result in the interruption of the white road between Roncovetro and Vedriano villages. In recent years, the Roncovetro landslide has been selected as a test site for evaluating new monitoring technologies based on Ultra-Wide Band (UWB) wireless sensors. Currently, it has been designated as a study area for the "Land-slide Enhanced Monitoring Network (LEMON)" project funded by the INGV. As part of the LEMON project, a small network of UWB wireless sensors has been installed on the landslide body to monitor its movement. The technology used was previously described in Intrieri et al. (2018) and Mucchi et al. (2018). The installed network consists of five sensors, comprising one master node and four slave nodes. The master node and one slave node were placed outside the area recently affected by displacements, while three nodes were positioned inside the landslide body. The acquisition frequency was set at one acquisition every three hours, totaling eight acquisitions per day. In November 2023, the Roncovetro landslide experienced a significant displacement that once again swept away the white road. This displacement was fully recorded by the UWB network. Additionally, an Unmanned Aerial System (UAS) survey was conducted before and after the displacement to offer a comprehensive view of the movement. In this work, we first describe the technological improvements and updates made to the UWB wireless network compared to previous works. Second, we describe the November 2023 displacement of the Roncovetro landslide as recorded by the UWB network with a frequency of one acquisition every three hours. And finally, we compare the data provided by the UWB network with the changes in the landslide detected through the comparison of pre- and post-UAS-derived orthophotos.

The RING (Rete Integrata Nazionale GNSS) is a research infrastructure developed for accurately measuring deformations at different spatial and temporal scales in the Eurasia-Africa plate boundary region (Avallone et al., 2010). Currently, the RING network (http://ring.gm.ingv.it/) is composed of 280 real-time transmitting remote sites, 70% of which are now equipped with full-GNSS (GPS, Galileo, Glonass and Beidou) instrumentation. The data streaming, in standard RTCM v.3 format, from these sites to the acquisition centre in southern Italy (Sezione Irpinia, Grottaminarda, AV) is managed by a tuned Ntrip Caster (https://igs.bkg.bund.de/ntrip/bkgcaster). The typical magnitude of the strongest events that occurred in the last century in this region (5.5-7) should require high accuracy (2-3 cm) GPS/GNSS time series to properly observe both static and dynamic coseismic displacements and, then, to properly model the earthquake source. Furthermore, the detection of any afterslip or, in general, any transient deformation should require even better accuracy (< 2 cm). The real-time GPS/GNSS data analysis has been implemented by means of the RTPPP software developed by GFZ (Ge et al., 2012). This software allows the determination of various Precise Point Positioning products with increasing accuracy (standard PPP, PPP with ambiguity resolution [PPP-AR], and PPP with regional augmentation [PPP-RA]). We performed some preliminary investigations on different (limited in time) datasets and we compared GPS-only and full-GNSS results. In the case of GPS-only PPP-RA solutions, the accuracies estimated on 24-hour data for the whole network amount up to 1.7 cm and 6 cm for the horizontal and vertical components, respectively. In the case of full-GNSS solutions, the same approach (PPP-RA) allowed an improvement of about 22% on both horizontal and vertical components (1.3 cm and 4.6 cm). Furthermore, we compared both GPS-only and full-GNSS solutions with another method, i.e. by using a short-term accuracy analysis. Using 60-s or 120-s sliding windows, that should better simulate the time span for detecting coseismic displacements, we can achieve 0.5 cm and 1 cm for horizontal and vertical components, respectively, for GPS-only solutions, and 0.3 cm and 0.5 cm for full-GNSS ones. Finally, for a few examples of earthquakes that recently occurred in Italy, we will show comparisons between post processed high-rate solutions carried out by Gipsy-Oasis II solutions and those obtained by RTPPP simulating real-time time series. The obtained accuracies will demonstrate the reliability of the RING infrastructure real-time GNSS solutions for early warning and rapid response applications.

Fault maturity has long been recognized as a critical control on coseismic behavior, but its influence remains underexplored in compressional settings, particularly offshore. This study investigates the offshore 2022 Mw5.8 earthquake in the northern Adriatic Sea using an integrated multidisciplinary approach that combines seismic reflection data, well logs, on- and offshore GNSS measurements, and instrumental and historical seismology. We identify the northwestern segment of a regional thrust (the Cornelia thrust) as the seismogenic source, where the thrust geometry, the low cumulative displacement (<0.3 km), and the structural setting suggest limited fault maturity. Our finite-fault model reveals a down-dip propagating rupture and a low rupture velocity (similar to 1.3 km/s), markedly lower than values typical for mature thrusts. The integration of geological and seismological observation, highlights how structural immaturity correlates with seismic behavior. In particular, our analysis confirms that low rupture velocities are indicative of fault immaturity, also along active thrust fronts. Furthermore, GNSS data constrain a long-term slip rate of similar to 1 mm/yr for the thrust, consistent with geologically derived longer-period rates. The joint analysis of coseismic slip with long-term strain accumulation and historical seismicity provides significant clues for the seismic cycle. These findings provide new insights into the seismogenic potential of immature thrust systems and emphasize the importance of evaluating fault maturity as part of seismic hazard assessment, particularly in offshore compressional belts where direct observation is limited.

The fast individuation and modeling of faults responsible for large earthquakes are fundamental for understanding the evolution of potentially destructive seismic sequences. This is even more challenging in case of buried thrusts located in offshore areas, like those hosting the 9 November 2022 Ml 5.7 (M w 5.5) and M L 5.2 earthquakes that nucleated along the Apennines compressional front, offshore the northern Adriatic Sea. Available on- and offshore (from hydrocarbon platforms) geodetic observations and seismological data provide robust constraints on the rupture of a 15 km long, ca. 24° SSW-dipping fault patch, consistent with seismic reflection data. Stress increase along unruptured portion of the activated thrust front suggests the potential activation of longer portions of the thrust with higher magnitude earthquake and larger surface faulting. This unpleasant scenario needs to be further investigated, also considering their tsunamigenic potential and possible impact on onshore and offshore human communities and infrastructures.

Tidal sea level variations in the Mediterranean basin, although altered and amplified by resonance phenomena in confined sub-basins (e.g., Adriatic Sea), are generally confined within 0.5 meters and exceptionally up to 1.5 meters. Here we explore the possibility of retrieving sea level measurements using data from GNSS antennas on duty for ground motion monitoring and analyze the spectral outcomes of such distinctive measurements. We estimate one year of GNSS data collected on the Mediterranean coasts in order to get reliable sea level data from all publicly available data and compare it with collocated tide gauges. A total of eleven stations were suitable for interferometric analysis (as of 2021), and all were able to supply centimeter-level sea level estimates. The spectra in the tidal frequency windows are remarkably similar to tide gauge data. We find that the O1 and M2 diurnal and semidiurnal tides and MK3, MS4 shallow sea water tides may be disturbed by aliasing effects.

GINGER (Gyroscopes IN General Relativity) project aims to directly measure the Lense-Thirring (LT) and de Sitter (dS) effects on the Earth and it is based on an array of underground Ring Laser Giroscopes (RLG), the most sensitive inertial sensors to measure the rotation rate of the Earth. Since LT and dS act on a ring laser as angular rotation vectors summed to the earth rotation rate, by using at least two gyroscopes it is possible to retrieve the General Relativity (GR) contribution to the rotation rate. The kinematic component is independently measured by the International Earth Rotation and Reference Systems Service (IERS) with very high accuracy. Ginger could also make it possible to discriminate among different theories, minimizing modeling. The measurement of the Earth angular rotation rate, in order to be fruitful for a fundamental physics test, has to have sensitivity of 1 part in 10(9) or better. The most recent analysis of our prototype GINGERINO data indicate a sensitivity better than 1 part 10(12), i.e. 0.1% of the LT term.

We present the geomorphological map of the upper sector of the Roncovetro active landslide (Enza Valley, Emilia-Romagna, Italy). The 1:1500 scale map provides an accurate picture of the landslide in October 2014. The map is mainly based on the data collected during an airborne LiDAR survey. The capability of LiDAR to 'penetrate' the vegetation cover makes these data the most complete and accurate topographic dataset of this landslide. The map shows that the upper sector of the Roncovetro landslide consists of gravity- and water runoff-related forms. Gravitational features are linked to sliding and flowing movements that characterize the short- and long-term behaviour of the landslide. By comparing the 2014 LiDAR-Digital Elevation Model (DEM) with the 1973 DEM provided by the Emilia-Romagna Region, we calculated that 6.2 +/- 0.8 x 105 m3 of material has moved from the top of the Roncovetro landslide in about 40 years.

Among the various applications of astrometry in astronomical geodesy we must point out the accurate time frame maintenance, the measurement of the Earth rotation, and the study of the local geoid. At the time, the authors have found being no mention of use of astrometry techniques dedicated to measure variations of inclination of a ground infrastructure. We present herein a device composed by a tiny telescope coupled with a CMOS astronomical camera used to acquire star field images overnight. The pointing angle of the telescope is accurately computed by a process called plate-solving and then actualized to account for Earth precession and nutation. A series of tests was conducted for a preliminary assessment of the instrument performances. The results proved that the sensitivity of this cost-effective device is in the range of 10–20 μrad, while long-term repeatability is of the order of tens μrad, comparable to MEMS inclinometers, but without the need of frequent recalibration operations.

In this work we present and discuss new geodetic velocity and strain-rate fields for the Euro-Mediterranean region obtained from the analysis of continuous GNSS stations. We describe the procedures and methods adopted to analyze raw GPS observations from >4000 stations operating in the Euro-Mediterranean, Eurasian and African regions. The goal of this massive analysis is the monitoring of Earth’s crust deformation in response to tectonic processes, including plate- and micro-plate kinematics, geodynamics, active tectonics, earthquake-cycle, but also the study of a wide range of geophysical processes, natural and anthropogenic subsidence, sea-level changes, and hydrology. We describe the computational infrastructure, the methods and procedures adopted to obtain a three-dimensional GPS velocity field, which is used to obtain spatial velocity gradients and horizontal strain-rates. We then focus on the Euro-Mediterranean region, where we discuss the horizontal and vertical velocities, and spatial velocity gradients, obtained from stations that have time-series lengths longer than 6 and 7 years, which are found to be the minimum spans to provide stable and reliable velocity estimates in the horizontal and vertical components, respectively. We compute the horizontal strain-rate field and discuss deformation patterns and kinematics along the major seismogenic belts of the Nubia-Eurasia plate boundary zone in the Mediterranean region. The distribution and density of continuous GNSS stations in our geodetic solution allow us to estimate the strain-rate field at a spatial scale of ∼27 km over a large part of southern Europe, with the exclusion of the Dinaric mountains and Balkans.

The RETRACE-3D project (centRal italy EarThquakes integRAted Crustal model) focused on the revision of all the available geological and geophysical data in the area interested by the 2016-2018 seismic sequence of central Italy, with the final aim to reconstruct a reliable and consistent 3D geological model of that area. It is based on a collaboration, which was framed into a formal agreement, between Dipartimento della Protezione Civile (the Italian Civil Protection Department), Istituto di Geologia Ambientale e Geoingegneria, and Istituto per il Rilevamento Elettromagnetico of the Consiglio Nazionale delle Ricerche, Istituto Nazionale di Geofisica e Vulcanologia, and Istituto Superiore per la Protezione e la Ricerca Ambientale. The agreement purpose was to develop a project aimed at the geological and seismotectonic characterisation of the crustal volume hosting that seismic sequence. We present and discuss the approach, methodology and results of the project. The 3D geological model of the study area is developed in detail down to a depth of about 12 km, and extended to the Moho based on available regional-scale information.

The analysis of long time series of Global Navigation Satellite System (GNSS) observations has recently evidenced that the slow tectonic processes are not the only ones producing the observed slow deformations, but the Earth's crust reacts also to stresses induced by pressure variations and water circulation. The basic mechanisms are substantially of two kinds: deformations induced by the elastic response of the loaded surface and deformations due to the poroelastic properties of the ground. These mechanisms are quite different, in the first case the water load causes subsidence, in the second uplift; both create horizontal deformations moving away from the centre of deformation. Under anisotropic conditions, water pressure changes in poroelastic soils can induce large horizontal deformations especially where highly fractured rocks may provide permeability for fluid flow. Both elastic and poroelastic phenomena are observable and measurable by continuous GNSS monitoring of ground deformations. Both can be triggered by periodical atmospheric processes but also by extreme events, like heavy rainfalls. We will show a few case studies, observed in the Italian area, that demonstrate how the deformation patterns, at different repeating periods, clearly correlate with groundwater circulation in different environmental condition.

We provide a dataset of 3D coordinate time series of 37 continuous GNSS stations installed for stability monitoring purposes on onshore and offshore industrial settlements along a NW-SE-oriented and ~100-km-wide belt encompassing the eastern Italian coast and the Adriatic Sea. The dataset results from the analysis performed by using different geodetic software (Bernese, GAMIT/GLOBK and GIPSY) and consists of six raw position time series solutions, referred to IGb08 and IGS14 reference frames. Time series analyses and comparisons evidence that the different solutions are consistent between them, despite the use of different software, models, strategy processing and frame realizations. We observe that the offshore stations are subject to significant seasonal oscillations probably due to seasonal environmental loads, seasonal temperature-induced platform deformation and hydrostatic pressure variations. Many stations are characterized by non-linear time series, suggesting a complex interplay between regional (long-term tectonic stress) and local sources of deformation (e.g. reservoirs depletion, sediment compaction). Computed raw time series, logs files, phasor diagrams and time series comparison plots are distributed via PANGAEA ( https://www.pangaea.de ).

The Adria microplate is the foreland of the oppositely verging Apennines and Alps or Dinarides fold-thrust belts associated to the related subduction zones. Along its western margin, the Adria plate hosts the active Northern Apennines accretionary prism, which is buried under the Adriatic Sea and the Po Plain. The interpretation of seismic reflection profiles and borehole data allowed us to define the geometry of the transition from the Apennines fold-thrust belt to its undeformed foreland. Moreover, continuous GPS (CGPS) data from offshore hydrocarbon platforms anchored to the seabed of the northern Adriatic plate allow to measure present-day kinematics. Although the CGPS signals are affected by non-tectonic components associated with hydrocarbon extraction, the integration of geodetic analysis, subsurface geological reconstructions, and analytical modeling allowed us to constrain the ongoing tectonic activity. Shortening is currently accommodated by aseismic slip along the basal detachment, likely accumulating elastic energy along the frontal ramp that may eventually seismically slip. Our multidisciplinary study suggests that the study area may not be sheltered from relevant seismic sequences similar to the Mw 6 Emilia 2012 events and that the occurrence of potential seismogenic sources in the area should be carefully evaluated. Similar studies may be useful to constrain the present-day activity in other marine areas and to identify potential and hitherto unrecognized seismogenic sources along the entire Apennines belt and other accretionary prisms worldwide.

Water supply from karst sources is a worldwide natural resource and the exploitation is tied to the knowledge of the positions of the hydrologic channels. We show that surface deformation induced by flood events in karst conduits is observable, and consists in uplift and outward movement from the hydraulic channel. Precipitation events produce the natural occurrence of subsurface hydraulic overpressure up to 1 MPa. Numerical modeling shows that the stresses are so strong to uplift and dislocate the surface by several mm and induce tilts in the order of microradians. The naturally induced deformation is compatible with a transient internal pressure loading of a channel. The results can be used to find new channels with dense GNSS networks. Sea water incursion and channels accessed for tourism could be monitored. Seismicity has been shown to have a seasonal variation in some areas, which could be explained by the subsurface stresses induced by the natural subsurface overpressure. The pressure induced deformation is expected to be observed in all karstic systems worldwide.

The rapid development of several permanent GNSS networks in Italy has made available a huge amount of GNSS observations, giving the chance to figure out and significantly improve the spatial and temporal resolutions of the crustal deformation in the Italian area. More than 20 GNSS networks, promoted and managed by different institutions, constitute the grid of monitoring stations that includes over 1000 permanent stations, mainly devoted to real-time positioning services but that has proven to be suitable for monitoring slow deforming processes, such as for instance, intraplate deformation processes. The whole set of raw GPS data is routinely processed at INGV providing daily solutions of station coordinates and estimating linear velocities for each station. The information content of coordinate time series is wide, the station position variations incorporate linear and non-linear effects caused by geophysical phenomena of different nature, of which we show some evidences. The sectors where the permanent network is augmented with non-permanent sites allows to study tectonic processes with a finer resolution.