GeoHazards doi: 10.3390/geohazards7030083

Authors: Maria Eleni Diamantidou Panagiota S. Katsimpini George A. Papagiannopoulos George D. Hatzigeorgiou

This study investigates the three-dimensional seismic response of plan-irregular reinforced concrete (RC) frame structures subjected to near-fault pulse-like ground motions. The primary scientific contribution lies in evaluating how perimeter-distributed, short-stroke displacement-activated hysteretic dampers interact with complex structural torsional modes under the coupled influence of soil–structure interaction (SSI). Through unscaled nonlinear time–history analyses, this research exposes a critical vulnerability: foundation flexibility elongates the structural period, moving the system into close resonance with near-fault pulse content and more than doubling peak inter-storey drift demands. Concurrently, we demonstrate that the supplemental hysteretic system provides immediate elastic stiffness that successfully counteracts this SSI-induced period elongation, restricting peak drift amplifications to under 0.21% while actively mitigating torsional twisting. These findings provide a quantitative framework for the dual management of foundation flexibility and torsional irregularity using short-stroke metallic yielding devices.

GeoHazards doi: 10.3390/geohazards7030082

Authors: Dimitrios Malamataris Philippos Ganoulis Panagiota Galiatsatou Iraklis Nikoletos Haris Prapas Dimitrios Galiatsatos

Land Use and Land Cover (LULC) change is widely acknowledged as a pivotal driver of environmental change, exerting an escalating influence on surface hydrological processes. The accelerating pace of LULC alterations in response to burgeoning human populations underscores the pressing need for a comprehensive evaluation of their ramifications on surface runoff dynamics. This study investigates the impacts of LULC changes on flood behavior in a Mediterranean watershed in Crete, Greece (Geropotamos watershed). LULC data spanning the years 1990, 2006, and 2018 were procured from the European CORINE Land Cover database at a refined spatial resolution. The HEC-HMS hydrological model is employed to simulate peak discharge and associated hydrograph characteristics under varying recurrence intervals. Subsequently, selected river segments within the studied catchments undergo hydrodynamic flood modelling using the HEC-RAS hydraulic model. Flood depth maps are generated to illustrate the evolution of inundated areas relative to LULC change. The overarching objective of this research is to furnish a comprehensive understanding of how spatiotemporal variations in land use and land cover in-fluence flood characteristics, thereby facilitating informed decision making for sustainable planning.

GeoHazards doi: 10.3390/geohazards7030081

Authors: Chia-Hao Chang Kuo-Chen Ma An-Chi Li

In large-scale seismic scenarios, the operational continuity of evacuation shelters is frequently compromised by limited governmental capacity, necessitating the strategic integration of Disaster Relief Volunteers (DRVs). Traditional assessments often rely on coarse regional aggregates, overlooking the critical spatial mismatch between volunteer availability and localized demand. In this study, a high-resolution, spatially explicit framework was developed to evaluate urban operational resilience in New Taipei City. Utilizing the TERIA platform, a nocturnal magnitude 6.8 Shanjiao Fault rupture was simulated, identifying that approximately 460,000 individuals would be affected, with shelter demand reaching 300,000—double the current capacity. Service areas were delineated using ArcGIS Network Analyst (Dijkstra’s algorithm) based on an 800 m walking threshold, further refined by a secondary assignment rule to redistribute “shadow demand” from peripheral populations. Quantitative analysis of the newly introduced “DRV shortfall” metric reveals that 74% of shelters (148/200) face concurrent spatial and manpower saturation. Notably, 42 analysis units lack resident volunteers entirely, with the most severe shortfall magnitude reaching 361 DRVs at a single “high-risk convergence node”. These results uncover a profound deficiency in urban disaster resilience driven by significant spatial mismatch. This research contributes a three-fold advancement: (i) the high-resolution coupling of volunteer residential data with dynamic demand patterns; (ii) the formalization of the DRV shortfall as a standardized metric for resource adequacy; and (iii) the formulation of a strategic policy framework for multi-shelter activation sequencing, “Support Hub” designation, and resource synchronization in hyper-dense urban environments.

GeoHazards doi: 10.3390/geohazards7030080

Authors: Zafarjon Sultonov Hari K. Pant

Lake Sarez in Tajikistan, formed by a major earthquake-induced landslide in 1911, is located in the highly seismically active Pamir–Hindu Kush region. The lake is impounded by the Usoi Dam, one of the largest natural landslide dams in the world, which has raised concerns regarding its long-term stability and associated downstream flood hazards. Due to its geomorphological setting and potential exposure to multiple triggering mechanisms, including seismic activity and landslides, Lake Sarez is widely considered a high-consequence hazard system. Although the dam has remained stable for over a century and is currently monitored using modern geodetic and satellite-based technologies, uncertainties remain regarding its internal structure and response to extreme external forcing. While existing early warning systems enhance preparedness in downstream communities, effective long-term risk reduction requires continued monitoring, improved hazard modeling, and strengthened regional cooperation. This review synthesizes existing studies on the geological setting, hazard potential, stability assessments, and disaster risk management strategies related to Lake Sarez. It highlights the importance of integrated multi-hazard analysis and precautionary risk governance in managing low-probability but high-impact natural dam failure scenarios.

GeoHazards doi: 10.3390/geohazards7030079

Authors: Jing Zhang Yang Cheng Liang Wang Helong Liu Jiajia Zhu Zhengwei Li Tianzheng Li

Accurate characterization of subsurface stratigraphy is essential for reliable landslide stability assessment. However, stratigraphic models constructed solely from sparse borehole data are often constrained by incomplete spatial coverage and substantial interpretive uncertainty. To address this issue, this study developed an integrated probabilistic stratigraphic modeling framework that combines borehole data with electrical resistivity tomography (ERT) data. In the proposed framework, borehole logs provide direct lithological labels and spatial prior information, while the inverted ERT resistivity profile is introduced as a continuous geophysical constraint. Specifically, logarithmic resistivity and the borehole-derived expected stratigraphic configuration were combined into a support vector machine classifier to establish a nonlinear mapping between geophysical responses and stratigraphic categories. A bootstrapping strategy was also used to quantify the stratigraphic uncertainty. The proposed method was then applied to the Panzhuangzu Landslide in Henan Province, China. Based on the probabilistic stratigraphic models, multiple plausible stratigraphic realizations were generated, and their corresponding stability responses are evaluated through numerical analysis. Monte Carlo simulations were further performed to examine how stratigraphic uncertainty propagates into landslide stability predictions. The results show that incorporating ERT data improves the geological plausibility of the inferred stratigraphy. Compared with the borehole-only case, the results obtained from the integrated framework exhibited reduced uncertainty in both the inferred stratigraphic model and the corresponding landslide stability assessment. These findings indicate that the proposed borehole–geophysical data fusion method can provide a more reliable geological basis for landslide stability analysis.

GeoHazards doi: 10.3390/geohazards7020078

Authors: John B. Rundle Ian Baughman Andrea Donnellan Lisa Grant Ludwig Geoffrey Fox Kazuyoshi Nanjo

In this paper, we describe a method for computing calendar time forecasts in a local area for large earthquakes of a target magnitude MT using a count of small earthquakes in the magnitude range MS to MT in the area. Using the idea that the Gutenberg–Richter (GR) relation is valid throughout the surrounding region, we define an ensemble of earthquakes in larger surrounding regions to be used in computing the forecast. What follows is simple data mining. “Local” is defined by the probability of a large earthquake occurring within a defined circle of arbitrary radius surrounding a point of interest. The main (and for that matter, the only) assumption for all these works is that the GR magnitude–frequency relation holds. The method has significant skill, as defined by the Receiver Operating Characteristic (ROC) test, which improves as the time since the last major earthquake increases. The probability is conditioned on the number of small earthquakes n(t), with M ≥ MS = 3.49, that have occurred since the last large earthquake. The probability is computed directly as the Positive Predictive Value (PPV) associated with the ROC curve. The method is compared with the UCERF3 forecasts for the UCERF3-defined geographic boxes centered on Los Angeles and San Francisco and serves as an indicative benchmark. The method is then applied to a 125 km radius circular area around Los Angeles, California, following the 17 January 1994 magnitude M6.7 Northridge earthquake, and short-term forecasts (1-year and 5-year) are computed. We further apply the method to six additional geographic regions with validation by comparison with an estimate of the time-independent conditional Poisson probability. These regions are Athens, Greece; Chengdu, China; Jakarta, Indonesia; Lima, Peru; Santiago, Chile; and Tangshan, China.

GeoHazards doi: 10.3390/geohazards7020077

Authors: Batuhan Kahvecioğlu Sinan Melih Nigdeli Gebrail Bekdaş Sanghun Kim Zong Woo Geem

This study investigates the comparative effectiveness of Lead Rubber Bearing (LRB) and Friction Pendulum System (FPS) isolation units under varying seismic hazard levels and soil classes, within the framework of the Turkish Building Earthquake Code (TBEC 2018). The assessment was conducted in two stages. First, keeping the site class constant, multiple locations characterized by different seismic hazard levels are examined. Second, a fixed geographical location is considered to evaluate the influence of different site classes on isolator response. The performance of the isolation systems is evaluated in terms of displacement demand, base shear ratio, and code-based verification criteria. Additional sensitivity checks were performed using selected limit values to better understand the response trends under changing hazard and soil parameters. The findings highlight how soil amplification effects and seismic intensity levels influence the relative advantages of LRB and FPSs. The results provide practical insight for the selection of seismic isolation systems in hazard-prone regions, contributing to improved performance-based decision-making in earthquake-resistant design. The isolator parameter choices were set based on average catalogue values provided by manufacturers to make this research an example. As a result of the analysis of the isolators’ performance, it was concluded that the FPS-type isolator performed better as acceleration values increased.

GeoHazards doi: 10.3390/geohazards7020076

Authors: Hajar Mrabet Ibtissam Latachi Tajjeeddine Rachidi Mohammed Karim

Wildfires are a growing threat in Mediterranean regions where climate variability and land-use practices increase vulnerability to fire risk. Developing effective prediction models is essential for robust wildfire management, particularly in such data-scarce environments. Focusing on data-scarce Mediterranean environments, with reference to environmental conditions observed in Morocco, this review presents prediction models across three methodological categories: spatial risk mapping, temporal forecasting, and fire spread simulation, alongside the satellite data products that support their deployment. Each category is assessed in terms of predictive performance, data requirements, and adaptability to low-resource environments. XGBoost showed strong applicability in data-scarce Mediterranean contexts, while ARIMA was validated for forecasting fire-relevant time series under limited data resources. Freely accessible MODIS-derived products represent a significant asset to the region. Based on this synthesis, a hybrid XGBoost-ARIMA framework incorporating MODIS-derived inputs and SHAP-based interpretability is proposed as a promising candidate architecture to be validated after further investigation. The findings aim to support researchers, land managers, and policymakers in strengthening local wildfire prevention and mitigation efforts by aligning model capabilities with regional data and environmental constraints.

GeoHazards doi: 10.3390/geohazards7020075

Authors: Xin Zhang Fang Wang Hao Yang Shixiao Liu

Rainfall is a critical factor inducing slope instability, and accurate prediction of the factor of safety (FOS) of slopes under rainfall conditions is of paramount importance for disaster prevention and mitigation. Conventional numerical simulation methods incur high computational costs, while individual machine learning models are often insufficient to adequately capture the nonlinear spatiotemporal evolution characteristics of multiple factors under coupled multi-physics fields. To address these limitations, this paper proposes a Transformer–LSTM prediction framework. First, a fluid–structure coupling model for rainfall-affected slopes is constructed using COMSOL, and multi-factor orthogonal experiments are performed to generate multi-dimensional time-series data. Subsequently, a Transformer–LSTM fusion deep learning model is built, in which LSTM is employed to extract the temporal dynamic characteristics of rainfall infiltration, and the self-attention mechanism of the Transformer is leveraged to enhance feature extraction and global dependency modeling of key disaster-causing factors. Experimental results demonstrate that the Transformer–LSTM model significantly outperforms traditional PSO-LSTM, PSO-SVM, and standalone Transformer or LSTM models in terms of both prediction accuracy and generalization capability. Its coefficient of determination (R2) remains above 0.94, and key evaluation metrics—including mean absolute error (MAE), root mean square error (RMSE), and mean absolute percentage error (MAPE)—attain the lowest values among the compared models. Furthermore, the SHAP (SHapley Additive exPlanations) interpretability framework is introduced to quantitatively elucidate the model’s predictive decision-making and to establish a physically grounded causal mapping with geotechnical mechanisms. It is confirmed that effective cohesion and slope angle exert a dominant interactive effect on the degradation of slope stability, providing data-driven support for wide-area monitoring of rainfall-induced landslides.

GeoHazards doi: 10.3390/geohazards7020073

Authors: Nadir Murtaza Ghufran Ahmed Pasha

Flooding has become increasingly severe due to rapid urbanization and changing hydrological conditions, necessitating effective and sustainable mitigation strategies. This study investigates the hydraulic performance of a hybrid flood defense system comprising a dike, a moat, and vegetation under varying surface roughness conditions. The results demonstrate that increasing roughness significantly enhances flood mitigation performance by improving energy dissipation and delaying the propagation of floodwater. A maximum energy reduction of approximately 75.56% and a delay in floodwater arrival of up to 65% were observed under higher roughness conditions. In contrast, increasing flow intensity reduced system efficiency, highlighting the importance of optimizing roughness under varying hydraulic conditions. The findings reveal that surface roughness is the dominant factor controlling flow resistance, turbulence generation, and hydraulic jump formation within the system. The novelty of this study lies in systematically quantifying the combined effect of roughness across structural and vegetative components within a hybrid defense framework. These results provide a practical basis for the design and optimization of eco-engineered flood defense systems, offering a cost-effective approach for reducing flood risk in riverine environments.

GeoHazards doi: 10.3390/geohazards7020074

Authors: Stelios Karozis Maria Gavrouzou Diamando Vlachogiannis Athanasios Sfetsos

Greece and the eastern Mediterranean are among the regions that are most exposed to climate-driven natural hazards, with wildfires, floods, and extreme rainfall events consistently producing significant socioeconomic and environmental impacts. Although previous literature has addressed each hazard type individually, a systematic, comparative analysis of the atmospheric circulation regimes associated with all three hazard categories within a unified Lagrangian framework has not yet been conducted for Greece. In this study, a 96 h HYSPLIT back-trajectory analysis driven by ERA5 reanalysis data, combined with k-means clustering, is employed to characterise the air mass origins associated with extreme events in Greece from 2000 to 2020 at two atmospheric levels: 750 m and 3000 m above sea level. Wildfire events are predominantly linked to short-distance northeast airflow at 750 m, and are directly associated with the Etesian wind system and to a coherent northwest-west Mediterranean signal at 3000 m, reflecting the influence of the summer blocking anticyclone over Europe. Conversely, flood events are dominated by northerly flow at 750 m, driven by the eastern flank of Mediterranean depressions. These results indicate that flooding in Greece is primarily conditioned by surface cyclogenesis, regardless of the upper-level flow geometry. Extreme rainfall events exhibit the most complex structure, with a dominant upper-level cluster that describes a recurving trajectory consistent with cut-off low dynamics. Cross-hazard comparisons demonstrate that similar near-surface trajectory patterns may arise from different atmospheric drivers, underscoring the necessity of integrating Lagrangian trajectory classification with additional context, such as thermodynamic and seasonal, to enable robust multi-hazard attribution and enhance early warning capabilities in the eastern Mediterranean.

GeoHazards doi: 10.3390/geohazards7020072

Authors: Gemma Musacchio Elena Eva Fabrizio Meroni Stefano Solarino Luigi Zarrilli

Earthquake risk communication often remains centered on event parameters and structural collapse, while local site effects, building response and non-structural elements vulnerability shape how earthquakes are experienced and what people can do to reduce risk. This study examines whether a multi-modal, experience-based strategy focused on these dimensions, which are referred to as “last mile” of seismic risk, can improve public understanding and support actionable preparedness behaviors. The case study is the exhibition “Terremoti: Attenti agli Elementi!—Dettagli che salvano la vita” (Earthquakes: Beware of the Elements!—Details that Save Lives), designed for school audiences and the general public. Its effectiveness was assessed through five multiple-choice questions administered before (N = 183) and after (N = 174) the visit to the Genoa Science Festival; responses were analyzed overall and by topic and demographic group. Correct answers increased significantly from pre- to post-visit, with the largest gains concerning local site effects (+43.29%) and household prevention measures (+49.45%), whereas building vulnerability (+14.97%) and building dynamic response (+0.49%) showed more limited improvement. These exploratory results suggest that seismic risk communication is more effective when abstract concepts are translated into observable, manipulable, and everyday experiences, and support a shift toward a “last-mile” framework of seismic risk communication.

GeoHazards doi: 10.3390/geohazards7020071

Authors: Gerassimos A. Papadopoulos

The Santorini volcano attracts global interest. The 17th century BCE Minoan eruption was likely the largest ever occurring in the Holocene. The evaluation of an enriched collection of documentary sources combined with geological observations showed that in historical times, 15 eruption episodes were recorded from the 2nd century BCE up to 1950 CE. Little-known episodes occurring in 1667 CE and 1773 CE were uncovered, analyzed and included in the catalogue. Due to many uncertainties and inconsistencies involved in the historical sources, a reliability score ranging from 1 (lowest) to 4 (highest) has been assigned to each one of the 15 episodes. This procedure was based on a Reliability Assessment Matrix, which is a novelty in historical volcanology. The size of an eruption was evaluated in terms of the 8-grade Volcanic Explosivity Index (VEI) by introducing a bimodal assignment form of “V or V + 1”, an approach used for the first time, instead of the traditional unimodal assignment of “V”. The VEI of 4–5 was assigned to the eruptions of 725/726 CE in the Santorini caldera and of 1650 CE in the Kolumbo submarine volcano. The rest of the eruptions were assigned with smaller VEIs. Completeness analysis of the catalogue with statistical tests and Monte Carlo simulation with random and non-random models as baselines showed a 10-fold increase in the eruption record in 450 years after the breakpoint of 1572 CE eruption compared to the 1747 years before that point implying that there are about 30 missing eruption events that escaped record in the pre-1572 CE historical interval. This statistically significant difference is interpreted as a bias discovery effect of anthropogenic origin, but further research is needed to show that it does not represent a drastic change of magma plumbing rate.

GeoHazards doi: 10.3390/geohazards7020070

Authors: Dionysios Chatzidakis Nikolaos Makrakis Prodromos N. Psarropoulos Yiannis Tsompanakis

Offshore high-pressure gas pipelines comprise critical infrastructure that often cross seismic regions for hundreds of kilometers. The intersection of such pipelines with seismic fault zones is frequently inevitable due to high costs or technical constraints of alternative routes. While typical mitigation measures, such as stronger materials or cross-sections and flexible joints, ensure pipeline integrity against earthquake-related geohazards, options for deep-water pipelines are more limited compared to onshore or even near-shore pipelines. This paper numerically investigates the efficiency of various mitigation approaches for surface-laid steel pipelines subjected to normal or reverse seismic faulting. Using ABAQUS finite-element software, the pipeline is simulated under realistic conditions for cohesive and non-cohesive seabed sediments. Critical fault displacements for different pipe steel materials, cross-sections, coatings, pressures, and orientations are calculated according to international standards. Results demonstrate that a 30° fault-pipe intersection angle is the most effective approach, increasing pipe’s capacity to fault dislocation by up to 90% for normal and 75% for reverse faults. Additionally, coating materials can increase a pipe’s resistance by up to 15%, whereas pressure difference variations may also have an impact. This study provides useful conclusions regarding the efficiency of the mitigation measures, the applicability of international standards, and the simulation of pipe–soil interaction.

GeoHazards doi: 10.3390/geohazards7020069

Authors: Swarna Bhowmick Renato Macciotta

Rockfall records for hazard assessments commonly present rockfall volume–cumulative frequency curves based on observations of rockfall occurrences that are noticed at or in the vicinity of infrastructure. These curves are in log–log scale, where the curves for larger volumes are fitted to a power law (linear fit in the log–log plot). The slope of this linear fit in log–log plots has been qualitatively attributed to rock mass characteristics (lithology, rock mass quality, discontinuities); however, there are not many direct insights that greenfield sites (new sites or areas with scarce to no data) could adopt for an order-of-magnitude estimation of rockfall hazard. This paper collects data from the literature, past and current, and presents details of these rockfall volume–cumulative frequency curves for different lithologies and rock mass qualities. Importantly, recent databases on rockfall frequency and volumes as obtained through change detection are utilized, which can provide more detailed and less biased rockfall occurrence data.

GeoHazards doi: 10.3390/geohazards7020068

Authors: Adnane Medrari Brahim Benzougagh Ibrahim Ouchen Halah Kadhim Tayyeh Ahmed Mageed Hussein Mohamed Mastere Taj Benyounes Najat El Ghazi Khaled Mohamed Khedher

The study analyzes a major deep-seated landslide affecting National Road 16 at KP 178+000 in the Rif region of northern Morocco, a corridor repeatedly impacted by geotechnical instability. Using historical information, detailed geological mapping, multiple field campaigns, and extensive subsurface investigations (core drilling, inclinometers), the authors characterize the site as a complex setting of metamorphosed, fractured, and altered peridotites overlain by Quaternary sediments dipping negatively toward the Mediterranean. The landslide is interpreted as deep-seated planar translational landslide and has been exacerbated by human activity, specifically the placement of excavated material on the downslope side during road upgrade works in late 2019. Inclinometer data show active movement extending to at least 20 m depth, confirming the deep-seated nature of the instability. Three remediation strategies were implemented: shifting the road alignment with terracing, combining road realignment with soil nailing and slope reprofiling, and installing large bored piles tied back with anchors, following recommendations from an external expert. The authors emphasize that robust geological investigations and properly regulated construction practices are essential to reduce landslide risk for infrastructure built in mountainous coastal regions.

GeoHazards doi: 10.3390/geohazards7020067

Authors: Igor Chiambretti Luca Lanteri Alessio Salandin Davide Tiranti

Slush flows are rapid mass movements of water-saturated snow and debris that develop when the liquid water content of the snowpack exceeds the critical threshold for the fully funicular regime, resulting in viscoplastic flow behavior fundamentally distinct from that of dry snow avalanches. These phenomena have been extensively documented globally as responsible for fatalities and economic damage comparable to those of snow avalanches. In the northwestern Italian Alps, the situation is markedly different. Until 2025, rain-on-snow (ROS) events in this region had produced amplified effects on the ground in the form of increased landslide activity, debris flow mobilization, and flooding, as typical consequences of snowmelt superimposed on pre-saturated soils but had not generated widespread slush flow phenomena. The 2025 season marked a critical threshold: for the first time, diffuse and unambiguous slush flow events were documented in Italian northwestern Alpine sectors, signaling a qualitative shift in the hazard regime rather than a mere quantitative intensification of known processes. Documented emergence of slush flows in the Italian Alps must be interpreted not as an anomaly but as a measurable indicator of climate change and of its progressive effects on the Alpine environment.

GeoHazards doi: 10.3390/geohazards7020066

Authors: Lorenzo Massa Franz A. Livio Maria Francesca Ferrario

Seismically triggered landslides represent a major secondary hazard of earthquakes, often causing widespread damage over large areas. Rapid and reliable mapping of such phenomena is therefore essential, particularly in emergency contexts. While numerous studies have addressed landslide detection in vegetated regions using optical remote sensing, arid and desert environments remain relatively underexplored due to the limited spectral contrast between stable and failed slopes. In this study, we evaluate the potential of an automatic pixel-based method for the rapid detection of seismic landslides in arid settings, using high-resolution optical imagery. The analysis focuses on the Mw 5.5 earthquake that struck the Northern Red Sea Region of Eritrea on 26 December 2022. A detailed inventory of 1393 coseismic landslides was manually mapped from pre- and post-event PlanetScope multispectral images and used both for geomorphological and macroseismic analyses and as training data for a threshold-based classification approach. Landslide detection was based on changes in the Redness Soil Index (RSI) and its differential (ΔRSI), combined with a One-Class Asymmetric Robust Gaussian classifier. Results show a good capability to delineate landslide-affected areas, although commission errors remain significant. Despite these limitations, the proposed approach, still in need of a more trained implementation in the future, proves its potential effectiveness for rapid mapping purposes, owing to its simplicity and minimal computational requirements. These results open the possibility to implement a fully automatic methodology in the future, when more landslides will be mapped and a model trained on different and normalized datasets will be implemented. The results demonstrate that pixel-based optical methods, particularly those relying on red-band spectral changes, represent a valuable tool for the preliminary assessment of earthquake-induced landslides in arid environments and may support emergency response and first-order hazard evaluation.

GeoHazards doi: 10.3390/geohazards7020065

Authors: Álvaro-Francisco Morote Jorge Olcina Brenda Tévar Alberto Alfonso-Torreño

The aim of this study is to analyze the perceptions of students in Primary Education (5th and 6th grades; n = 260; Valencian Community, Spain) regarding natural hazards, based on their personal experiences, memories, school-based instruction and preventive measures. Methodologically, the study is based on the administration of a mixed-type questionnaire. The high proportion of students reporting strong awareness (68.5%) suggests that school-based instruction is already contributing to a foundational level of risk perception. Floods associated with torrential rainfall are the most frequently recalled hazard, influenced by the cut-off low event of 29 October 2024 (Valencia) (72.3%). Furthermore, no significant differences were found between students who experienced or remembered a flood and those who did not, in terms of preventive measures received, indicating a consistent and homogeneous instruction. In conclusion, this study highlights that students hold a strong awareness of natural hazards, particularly floods, with uniform school-based training. The cut-off low 2024 event in Valencia stood out among other disasters, reinforcing the educational importance of water-related hazards in high-risk regions and underscoring the need to strengthen hydrological awareness as a key component for enhancing socio-territorial risk perception.

GeoHazards doi: 10.3390/geohazards7020064

Authors: Riazud Din Faheem Butt Farhan Ahmad Ali Raza

Earthquakes pose a serious threat to urban areas located in seismically active regions, particularly in developing countries where rapid urbanization and weak enforcement of building regulations increase the vulnerability of the built environment. Pakistan is highly exposed to seismic hazards due to its tectonic setting, and many residential buildings are constructed without adequate seismic design considerations. Therefore, assessing building vulnerability and understanding community perception of earthquake risk are essential for effective disaster risk reduction. This study investigates the relationship between the structural vulnerability of residential buildings and earthquake risk perception among residents in Peshawar, Pakistan. Two contrasting urban settlements were selected as case studies: WAPDA Town, representing a planned residential area, and Hashtnagri, representing an older unplanned settlement. A total of 400 buildings were surveyed through field investigations. Seismic vulnerability was assessed using the Rapid Visual Screening (RVS) method based on structural characteristics such as building age, number of floors, construction materials, structural irregularities, construction quality, and presence of seismic reinforcement features. A Physical Vulnerability Index (PVI) was developed to categorize buildings into different vulnerability levels. In addition, a questionnaire survey was conducted to evaluate earthquake risk perception among residents, and a risk perception index (RPI) was calculated. The results indicate that buildings located in the unplanned settlement exhibit significantly higher seismic vulnerability compared to those in the planned residential area due to poor construction practices, irregular structural configurations, and the absence of seismic-resistant features. Statistical analysis further reveals a positive relationship between physical vulnerability and earthquake risk perception, suggesting that residents living in structurally vulnerable environments tend to perceive higher earthquake risk. The findings highlight the importance of integrating structural vulnerability assessment with community awareness and preparedness programs. Implementation of seismic design provisions and improved enforcement of construction regulations, such as those specified in the Building Code of Pakistan 2022, can significantly reduce earthquake risk in rapidly growing urban areas. However, the present study did not directly evaluate the level of enforcement or compliance with the Building Code of Pakistan 2022 in either WAPDA Town or Hashtnagri. Therefore, the policy recommendations are intended as general implications derived from the observed vulnerability patterns.

GeoHazards doi: 10.3390/geohazards7020063

Authors: Jean-Paul Deroin Belkacem Boumaraf Hacini Messaoud

Multisource remote sensing data is utilised for the purpose of monitoring annual and interannual changes associated with climate change in the water bodies of the Chotts of Merouane and Melrhir, which are located in the Zone of Chotts in North Africa. These endorheic depressions are distinguished by recurrent flooding events of varying magnitude and frequency, which are contingent on fluctuations in climate parameters. It has been determined that certain cities located within the surrounding watersheds, such as Biskra, are subject to the intermittent threat of severe flooding. This has been shown to result in land degradation and soil salinisation during the drying-up process. A detailed examination of chronological data from the 1960s onwards reveals a decline in the frequency of flooding in Chott Melrhir in recent years. It is noteworthy that the region has not experienced any substantial flooding since 2020. This phenomenon is concomitant with the marked decline in precipitation levels observed in the region. Since 1980, there have been at least ten significant floods, resulting in varying degrees of damage and disruption. In contrast, Chott Merouane exhibits a more consistent hydrological pattern, with water flowing almost year-round due to wastewater and the drainage of the palm groves by the Oued Righ. Until the 1970s, the occurrence of flooding in the region was exclusively attributable to the direct overflow of the Biskra River and its tributaries. However, from the 1980s onwards, a new type of flooding emerged, linked to insufficient infiltration and drainage capacity in the soil and sewage systems during rainfall that was sometimes considered normal. The hydrological regime in the area has severe ramifications for the water supply and the state of the oases, which are vulnerable to salinisation.

GeoHazards doi: 10.3390/geohazards7020062

Authors: Diana Contreras Enes Veliu Dimosthenis Antypas Javier Hervas Matthieu Landès Laure Fallou Damiano Koxhaj Rémy Bossu Sean Wilkinson Jose Camacho-Collados Edmond Dushi

Collecting and analysing data after an earthquake is essential to determine its impact. In 2014, the European Mediterranean Seismological Centre launched the LastQuake system. Its app collects reports on the intensity users feel, along with comments that provide situational awareness. However, text data collected through crowdsourcing platforms is unstructured. Therefore, natural language processing techniques such as sentiment analysis and aspect-based sentiment analysis are necessary to extract meaningful information. On the 26 November 2019, following an earthquake in Albania, the LastQuake app recorded 28,220 reports with user comments. For the current analysis, we sampled comments posted on the exact day of the earthquake, in Albanian: 1678 comments (6%). The most frequent polarity detected in comments from LastQuake app users was negative (52%), followed by positive and neutral. However, manual classification is time-consuming and not feasible during the emergency phase. Therefore, we tested the accuracy of two automatic classification models for sentiment analysis: ‘troberta’ and ‘txlm’. These models were fine-tuned using already-classified text data from the 2020 Aegean earthquake. Using the manual classification as the reference to evaluate the accuracy of the automatic classification models for sentiment analysis yields accuracies of 71% for the ‘troberta’ model and 56% for the ‘txlm’ model.

GeoHazards doi: 10.3390/geohazards7020061

Authors: Davide Tiranti

Landslides, defined as downslope movements of rock, soil, or debris under the action of gravity [...]

GeoHazards doi: 10.3390/geohazards7020060

Authors: Zhiyun Liu Ziyang Wang Fuqing Cui Xiang Long Li Wang Te Liu Zhou Yang

Permafrost foundations are prone to settlement during thawing, resulting from both thaw settlement and thaw-induced compression. The relative contributions of these components are strongly influenced by soil structure and loading conditions. Therefore, clarifying their interaction and identifying the conditions for significant compressive deformation are essential for accurate predictions. Laboratory tests were conducted to determine the thaw-settlement and thaw-compression coefficients. A new index, the thaw proportion of thaw settlement, was introduced to quantify the relative contributions of the two deformation components. By combining this ratio with compressive strain characteristics, criteria for identifying significant thaw-compression deformation and the corresponding load–porosity conditions were established. In addition, multiple machine learning models were developed, and their predictive performance was systematically evaluated. The main findings are outlined as follows: (1) The thaw proportion of thaw settlement is controlled by soil type, natural water content, dry density, and external load, with clear differences among soil types. It increases with water content, but decreases with increasing dry density and load. (2) Significant thaw-compression deformation is defined by a compressive strain of 8%, and the corresponding load–porosity conditions are identified. (3) Machine learning models effectively predict permafrost deformation. After Bayesian Optimisation (BO), performance improves markedly, with the BO-Support Vector Machine (SVM) model achieving the highest accuracy for thaw-settlement-coefficient prediction (R2 = 0.85), and the BO-Extreme Gradient Boosting (XGBoost) model performing best for post-thaw compressive strain (R2 = 0.95).

GeoHazards doi: 10.3390/geohazards7020059

Authors: Fuhua Peng Weijun Wang Jingyun Hu Yinghua Huang Congcong Zhao

Dynamically grasping the scope of the caving zone and fractured zone in overlying strata is crucial for ground pressure control in sublevel caving mining. Taking Dahongshan Iron Mine as the research object, this study systematically analyzed the evolutionary characteristics of overlying strata caving during sublevel caving mining from 2009 to 2013. Microseismic monitoring was employed as the main method to monitor and locate rock mass fracturing, while roadway monitoring and borehole monitoring were used as auxiliary means to determine the caving boundary and fractured zone scope of overlying strata. Comprehensive analysis of the monitoring data showed that the elevation of the overlying strata caving zone expanded from 930 m to 1215 m, and the width of the fractured zone varied from 50 m to 75 m in different periods. To clarify the rock mass fracture mechanism, P-wave first-motion moment tensor inversion and the Ohtsu moment tensor decomposition method were adopted to classify fracture types. The results indicated that tensile fracturing-related microseismic events accounted for 76.2–80.2% of all events in different periods, demonstrating that tensile failure dominated the fracturing of overlying strata. After December 2012, the caving scope extended to the surface, and a surface collapse area of 290,000 m2 was formed by December 2013, which effectively eliminated the threat of sudden overlying strata caving disasters to the mine. The research results provide reliable technical support for ensuring mine safety production and can serve as a reference for similar sublevel caving mining projects.

GeoHazards doi: 10.3390/geohazards7020058

Authors: Mohammad Alamgir Hossain Md. Moklesur Ra​​hman Md. Anik Hossain

This study examines the relationship between land use–land cover (LULC) changes and drought risk dynamics in southwestern Bangladesh, focusing on the Kushtia District, Chuadanga District, Jhenaidah District, and Jashore District. Multi-temporal Landsat data (1994–2018) were used to classify six LULC types, and future scenarios (2028–2050) were projected using a CA–Markov chain model. The Combined Drought Index (CDI) was integrated with LULC fractions through Pearson correlation and linear regression to assess drought variability. Results reveal significant landscape transformation, with settlement areas expanding sharply (≈18–27% in 1994 to 66–85% by 2050), while agricultural land, vegetation, and water bodies declined across all districts. Strong statistical associations were observed between CDI and settlement (negative relationship), as well as agricultural land, barren land, and char land (R2 = 0.63–0.82, p < 0.05). Future projections indicate increasing drought vulnerability, particularly in Jashore District, where CDI may decrease from 0.67 (2028) to 0.35 (2050), suggesting a transition toward extreme drought conditions. The Jhenaidah District may shift toward mild drought conditions, while the Kushtia District and Chuadanga District show gradual declines in CDI values, remaining largely within the normal drought range. The findings highlight spatially varying linkages between land use dynamics and drought variability, underscoring the importance of sustainable land management strategies to mitigate potential future drought risks.

GeoHazards doi: 10.3390/geohazards7020057

Authors: Melti Roza Adry Akhmad Fauzi Bambang Juanda Andrea Emma Pravitasari

Indonesia experiences some of the world’s highest seismic activity, making earthquakes a major source of physical, economic, and social losses. To better quantify these impacts, this study proposes a comprehensive evaluation framework with two new metrics: the Seismic Severity Index (SSI) and the Seismic Impact Index (SII). The indices are derived using four weighting methods—Grey Relational Analysis (GRA), Equal Weights, the Entropy Weight Method (EWM), and Criteria Importance Through Intercriteria Correlation (CRITIC)—and applied to 28 regencies and municipalities affected by damaging earthquakes from 2016 to 2022. Results show that the 2018 earthquake, intensified by a tsunami and liquefaction, caused the most severe losses. Palu Municipality and Donggala Regency consistently recorded high SSI values across all weighting schemes. The SII further identifies Sigi Regency, Donggala Regency, and Palu Municipality as the most heavily impacted areas, although rankings varied by method. Overall, Sigi Regency, Palu City, Donggala Regency, North Lombok, West Lombok and Cianjur exhibit the highest combined severity and impact, while Garut, Ciamis, and Cilacap experienced relatively minor effects. The study concludes that integrating GRA with EWM and CRITIC yields a robust earthquake loss index to support future disaster risk reduction policies.

GeoHazards doi: 10.3390/geohazards7020056

Authors: Kushal Acharja Topu Fei Wang William Jenkins Coleman Vaughan

Cover-collapse sinkholes are one of the most hazardous geohazards, causing severe damage to civil infrastructure, roadway networks, and substantial economic disruptions. In the United States alone, the economic loss caused by cover-collapse sinkholes exceed USD 300 million annually. Despite extensive research on the causes and formation mechanisms of cover-collapse sinkholes, reliable prediction of the collapse range remains a significant challenge because the development of cover-collapse sinkholes occurs underground and is generally undetectable at the ground surface until collapse occurs. This study presents a comprehensive review of 162 peer-reviewed journal articles, technical reports, and case studies to systematically identify the key factors governing the collapse range of cover-collapse sinkholes. This paper covers several influencing factors for collapse range of cover-collapse sinkholes, including soil properties, geometric characteristics of cavities and soil cover, hydraulic conditions, and the presence of buried structures. Among these factors, soil cohesion, friction angles, void ratio, soil cover thickness, and cavity geometry are identified as the key influencing factors for the collapse range of cover-collapse sinkholes. In addition, existing prediction methods were also summarized, which are predominantly empirical and have limited capability to capture the influence of multiple factors on the collapse range. Based on the literature review, this study finally identifies current research gaps and suggests future directions for developing more accurate and integrated models to predict collapse range of cover-collapse sinkholes.

GeoHazards doi: 10.3390/geohazards7020055

Authors: Kostas Kalabokidis Olga Roussou Christos Vasilakos Palaiologos Palaiologou Dimitrios Zianis Katerina Trepekli Pau Brunet-Navarro José Ramón González-Olabarria José G. Borges Susete Marques Dagm F. Abate William M. Jolly Alan A. Ager

Greece is facing a wildfire crisis that parallels many other countries in fire-prone regions around the globe. Recent wildfire data for Greece point to an alarming trend of increasing fire size and severity catalyzed by climate change, lack of forest and fuel management, urban expansion into wildlands around major population centers, and rural exodus from areas that traditionally supported fire-resilient land uses. Fire management in Greece has long emphasized suppression with relatively little attention to prevention and coordination. In this paper, we identify key factors that are slowing progress towards a solution to the Greek wildfire crisis, including the current legislative framework around wildfire management that has contributed to conflicts and inefficiency. We then discuss specific policies to rebalance the current suppression emphasis by integrating new prevention strategies aiming to create fire-resilient landscapes and reduce wildfire impacts, widely adopt the use of technology, and enhance stakeholder cooperation for more efficient fire suppression. We also highlight how optimizing landscape scale management of fuels is contributing solutions to the wildfire crisis, specifically from the EU-funded FIRE-RES project.

GeoHazards doi: 10.3390/geohazards7020054

Authors: Betty Namugenyi Hadir Abdelmoneim Chérifa Abdelbaki Sameh Ahmed Kantoush Navneet Kumar Bayongwa Samuel Ahana Mohamed Saber

Floods increasingly threaten communities and infrastructure in Uganda due to climate variability and land use changes. This study assessed flood hazard, vulnerability, and risk in the Mpanga River Catchment using the Rainfall–Runoff–Inundation (RRI) model integrated with the Analytical Hierarchy Process (AHP). The RRI model showed good performance during calibration (NSE = 0.83) and validation (NSE = 0.71), enabling the generation of hazard maps for different return periods. Results revealed a clear escalation in flood extent with increasing return period, where inundation expanded from about 120.5 km2 in the 5-year event to nearly 348.4 km2 under the 100-year flood scenario. Vulnerability was evaluated through AHP using nine indicators (Land use, population density, distance to river, elevation, rainfall, slope, drainage density, Total Wetness Index, and soil type); however, only Land Use and population density were retained in the final mapping due to data relevance and weight dominance. Combining hazard and vulnerability produced risk maps that revealed most of the catchment falls under low to moderate risk, with high-risk areas concentrated in upstream urbanized zones. Validation with satellite-derived flood maps confirmed model reliability. Evaluation of mitigation strategies showed dams and channel improvements to be the most effective in reducing flood extent. The study provides a practical framework for flood risk management in data-scarce environments, supporting evidence-based planning and interventions.

GeoHazards doi: 10.3390/geohazards7020053

Authors: Michele Sisto Cristiano Fidani

A key component of research on disaster risk in modern-age society in the inland areas of the Campania Region, southern Italy, was discovered in parish registers. Ecclesiastical archives, containing thousands of largely unpublished pages, served as a rich source of information on disruption and casualties. The parish registers preserved in these archives from the 16th century provide demographic records as well as notes on the most terrible events that affected society at the time. They include the catastrophic effects of seismic events recorded in this sector of the southern Apennines, an area characterised by high seismicity due to the complex dynamics of the convergence zone between the African and Eurasian plates. New findings reveal a more precise number and previously unreported deaths in several villages, confirming and suggesting some macroseismic intensities for the 1694 seismic event; moreover, further evidence was found for the hypothesised 1692 seismic event. A greater number of deaths was observed in some villages during the 1702 and 1732 events. Parish documents provided details about local construction techniques adopted after the well-known earthquake of 1732, including the use of more resilient materials and design modifications.

GeoHazards doi: 10.3390/geohazards7020052

Authors: Muhammad Zubair Zafar Shah Junji Yagisawa

Rainfall-induced erosion poses a serious threat to river levee slopes, where raindrop impact and surface runoff trigger particle detachment, rill initiation, and gully development, leading to rapid soil loss and local instability. This study experimentally evaluated short-fiber reinforcement as an erosion-control measure for levee slopes under controlled rainfall conditions. Laboratory embankment models were constructed using a uniform soil mixture and compacted under consistent moisture conditions. Simulated rainfall was applied at intensities of 50 and 100 mm/h. Erosion progression was monitored through time-series observations and quantified using sediment collection and three-dimensional surface measurements. Comparative tests were performed on unreinforced and fiber-reinforced slopes to examine the influence of fiber bridging and surface anchoring on the initiation and development of erosion. The results showed that short-fiber reinforcement delayed rill formation and reduced soil loss. Under 50 mm/h rainfall, 1% coir fiber reduced the eroded mass by approximately 70%, whereas polypropylene fiber achieved approximately 42% reduction compared with the unreinforced control. These findings suggest that short natural fibers can effectively enhance the erosion resistance of compacted levee slopes under rain.

GeoHazards doi: 10.3390/geohazards7020051

Authors: Phil J. Watson Hak-Soo Lim

The Korean Peninsula is critically exposed to impacts associated with current and projected rising mean sea-levels (MSLs) associated with climate change. Rising MSL will continue to exacerbate existing coastal hazards (e.g., typhoon-driven storm surges, tidal inundation, beach erosion, etc.). This study updates the previous 2019 national sea-level rise assessment with an additional 7 years of tidal and satellite altimetry data. Having corrected the rate of “relative” MSL rise for vertical land motion, only Busan and Ulsan tide gauge records have not experienced an increase in the rate of “geocentric” MSL rise since the 2019 Assessment. At the 95% CL, the current rate of “geocentric” MSL rise at all stations accord with recent published estimates of the rate of global MSL rise. From satellite altimetry of the sea margins around the Korean Peninsula, there has been a small (≈1%) increase in the average regional trend of sea-level anomalies (SLAs) compared to the previous assessment. The most significant trend estimates in SLAs continue to increase in margins of the East Sea (Sea of Japan) between 35° N and 40° N with increases of around 11% in the average rate of trend above the 2019 Assessment.

GeoHazards doi: 10.3390/geohazards7020050

Authors: Mohammed Mussa Abdulahi Pascal E. Egli Zinabu Bora

Landslides are a critical environmental hazard in mountainous regions like eastern Uganda, posing serious threats to lives, infrastructure, and ecosystems. While recent advances in geospatial technology have improved hazard assessment, existing research often lacks high-resolution, cloud-based analysis for dynamic landscapes such as the Mount Elgon region. This study addresses that gap by developing a landslide susceptibility map (LSM) using Google Earth Engine (GEE), which integrates remote sensing and geospatial data for scalable analysis. The main objective is to identify landslide-prone zones by analyzing eight conditioning factors, namely slope, elevation, vegetation cover, rainfall, land use land cover, soil type, soil moisture, and groundwater levels using the weighted overlay method (WOM). The methodology produced a classified LSM with zones of high (37.7%), moderate (58%), low (2%), and very low (2.3%) susceptibility, with validation via historical landslide data and ROC analysis yielding an AUC of 0.76, confirming strong predictive performance. The study underscores the value of GEE in hazard modeling and provides actionable insights for targeted risk mitigation, sustainable land use planning, and early warning system development in landslide-prone areas.

GeoHazards doi: 10.3390/geohazards7020049

Authors: Gemma Aiello

In order to assess their influence on the marine hazard offshore the Cilento Promontory, the gassy sediments of the Cilento offshore have been thoroughly examined using the geological interpretation of a closely spaced grid of Sub-bottom Chirp profiles. Based on the general stratigraphic framework three areas have been previously identified, highlighting the different acoustic features occurring in the Cilento area. The acoustic anomalies include acoustic blanking, shallow gas pockets, and seismic units impregnated of gas, showing distinct acoustic responses. Understanding these anomalies and the related seismo-stratigraphic units in the offshore Cilento Promontory provides a valuable foundation for evaluating marine geohazards and may assist in developing strategies to mitigate geohazards in the Cilento area.

GeoHazards doi: 10.3390/geohazards7020048

Authors: Ke Ren Cheng Song Na Li Xiaodong Wang Zeming Wang Yanhai Liu

With the expansion of seismic exploration targets to deeper and more complex geological structures, traditional fault interpretation methods face significant challenges in terms of efficiency and accuracy. The extensive application of artificial intelligence (AI) technologies is driving the evolution of fault recognition techniques toward automation and intelligence. This paper systematically reviews the development of AI technologies in fault recognition, from traditional machine learning-based seismic attribute fusion analysis to deep learning-based end-to-end recognition and semantic segmentation. It provides a detailed discussion of key technological advancements, such as sample set construction, weak signal enhancement, and noise suppression. To address the current challenges, including the insufficient authenticity of synthetic data, poor model interpretability, and weak quantitative representation capabilities, this study proposes three future research directions: the development of benchmark datasets based on real geological evolution, the construction of interpretable model architectures that incorporate geological prior information, and the realization of multi-parameter collaborative intelligent fault system analysis. These directions aim to provide theoretical support for advancing the practical and industrial applications of intelligent fault recognition technology.

GeoHazards doi: 10.3390/geohazards7020047

Authors: Mikayel Gevorgyan Arkadi Karakhanyan Avetis Arakelyan Suren Arakelyan Hektor Babayan Gevorg Babayan Elya Sahakyan Lilit Sargsyan

Armenia is located within the central segment of the Arabia–Eurasia continental collision zone and is exposed to significant seismic hazard. This study presents an updated probabilistic seismic hazard assessment (PSHA) for Armenia based on an integrated seismotectonic framework incorporating active fault data, paleoseismological evidence, and historical and instrumental seismicity. A hybrid seismic source model was developed by combining fault-based characteristic earthquake sources with distributed background seismicity. Hazard calculations were performed using the OpenQuake engine within a logic-tree framework to account for epistemic uncertainties in earthquake occurrence and ground-motion prediction. Ground motion was estimated using a weighted set of ground motion prediction equations (GMPEs). Peak ground acceleration (PGA) hazard maps were computed for several return periods, with emphasis on the 475-year return period (10% probability of exceedance in 50 years). The results indicate PGA values across Armenia ranging from approximately 0.2 g to 0.5 g, with the highest hazard levels in northwestern Armenia along the Pambak–Sevan–Syunik Fault System. Hazard deaggregation shows that seismic hazard in major Armenian cities is primarily controlled by shallow earthquakes with magnitudes Mw 6.8–7.4 occurring within ~30 km of urban centers. The results provide a scientific basis for seismic hazard assessment, zonation, and earthquake risk mitigation in Armenia.

GeoHazards doi: 10.3390/geohazards7020046

Authors: Shouguo Yang Shuxin Mei Xiaofei Zhang Jun Liang

This study experimentally investigates the propagation characteristics of static pressure waves (S-waves) and dynamic pressure waves (D-waves) induced by coal and gas outbursts of varying intensities, utilizing a self-built 1:30 scaled laboratory mine ventilation model. Systematic measurements and quantitative analyses were conducted to determine waveform morphology, propagation velocities, attenuation laws, and frequency distributions. The results demonstrate that outburst-induced D-waves exhibit a distinct full-sinusoidal waveform, whereas S-waves present a half-sinusoidal profile. Notably, the wavelength of both wave types remains highly stable regardless of initial outburst intensity and propagation distance. Conversely, the wave amplitude is positively correlated with the outburst intensity and attenuates progressively with distance. Furthermore, D-waves demonstrate a significantly higher sensitivity to propagation distance than S-waves. Spectral analysis confirms that the primary energy of both pressure waves is concentrated in the ultra-low-frequency range below 1.0 Hz. The average propagation velocities of S-waves and D-waves were measured at 395.67 m/s and 280.27 m/s, respectively, indicating that S-waves propagate considerably faster. It should be noted that since these findings were derived under scaled laboratory conditions, direct extrapolation to full-scale, long-distance field roadways requires further validation. Ultimately, this work elucidates the fundamental propagation mechanisms of attenuated pressure waves within mine ventilation networks, providing critical waveform signatures for the remote identification and localization of underground disaster sources.

GeoHazards doi: 10.3390/geohazards7020045

Authors: Osman Nasanlı Devrim Türkan Kejanlı

Population growth and unplanned land use significantly contribute to transforming natural hazards into disasters. Earthquake-induced losses of life and property are often linked to inadequate planning decisions. The city center of Şanlıurfa provides a recent example, where the 6 February 2023 earthquake resulted in 340 fatalities and substantial material damage. Variations in urban planning over different periods have caused disaster risk to fluctuate even across short distances. This study examines Şanlıurfa’s urban development in terms of earthquake vulnerability. Using Geographic Information Systems (GIS) and the Analytic Hierarchy Process (AHP), the earthquake risk map reveals elevated risk in areas near fault lines and regions with high groundwater levels. Approximately 7% of the area is classified as very low risk, 54% as low risk, 37% as moderate risk, and 2% as high risk. Limited consideration of disaster-focused planning has led to both planned and unplanned developments in hazardous zones. Consequently, construction should prioritize low-risk areas, with necessary precautions applied in high-risk zones when unavoidable.

GeoHazards doi: 10.3390/geohazards7020044

Authors: Jing Meng Yulu Fan Chengjun Feng Peng Zhang Bangshen Qi Chengxuan Tan

The aim of this paper is to investigate dynamic adjustment of the in situ stress field and the stability of main faults in the Zhangbei strong seismic region. Firstly, we utilized in situ stress measurement and monitoring data to discuss the dynamic adjustment process of the in situ stress field. Subsequently, the Fault Slip Potential (FSP) v.1.0 software package was employed to calculate the fault slip potential of the main faults. Finally, the potential hazard of fault activity was assessed. The conclusions are as follows. (1) Since November 2015, the in situ stress field has been primarily influenced by NEE compressive tectonic action, with a slight enhancement in the near SN compressive tectonic action. (2) In the initial stage, NE-trending faults exhibited the highest stress accumulation levels, with near-EW-trending faults the lowest. Influenced by the enhanced near-SN-trending compressive action, as of 19 October 2020, near-EW-trending faults displayed the highest stress accumulation, followed by NW-trending faults, with NE-trending faults showing the least accumulation. (3) From November 2015 to October 2020, the in situ stress field was in a continuous accumulation process. Using the Shangyi–Pingquan fault as a boundary, fault activity in the southern part of the strong seismic region is more hazardous than that in the northern part.

GeoHazards doi: 10.3390/geohazards7020043

Authors: Xiaoyi Hu Jian Ye Yani Huang Haolin Liu Menghao Zhai Xue Li

This study develops a framework to capture spatiotemporal population dynamics and assess future earthquake exposure risk, using Hubei Province as a case study. Future population changes at the county level were projected under different shared socioeconomic pathways (SSPs). These projections were then integrated with NPP-VIIRS nighttime light data and the normalized difference vegetation index (NDVI) to simulate the spatiotemporal dynamics of the population from 2020 to 2070 at a 500 m grid resolution. Combined with seismic hazard zoning, the evolution of population exposure risk under different pathways was assessed. The results indicate the following: 1. Different SSPs profoundly influence future population exposure patterns. Under the SSP3 (regional rivalry) pathway, population growth is the fastest with the strongest agglomeration effect and significantly elevated exposure levels. 2. The refined spatiotemporal population model can more realistically reveal the heterogeneity and evolutionary trajectory of population distribution, providing a high-precision data foundation for exposure analysis and effectively enhancing the scientific rigor of risk assessment. 3. Population exposure risk under various pathways exhibits distinct spatiotemporal dynamics, and monitoring its evolution under different scenarios helps identify high-risk counties that require priority attention. This study is expected to provide precise scientific evidence for implementing differentiated disaster prevention and mitigation strategies and territorial spatial resilience planning in Hubei Province, while it demonstrates the forward-looking value of combining long-term scenario simulations with refined exposure assessments.

GeoHazards doi: 10.3390/geohazards7020042

Authors: Patsani Gregory Kumambala Grivin Chipula Ponyadira Corner Chikondi Makwiza

Malawi lies within the southern segment of the East African Rift System and is exposed to infrequent but potentially damaging earthquakes. While recent advances in fault mapping, seismic monitoring, and hazard modelling have substantially improved scientific understanding of earthquake hazard in the Malawi Rift Zone, the practical reduction in seismic risk remains limited. This Perspective paper argues that earthquake resilience in Malawi is constrained less by scientific uncertainty than by challenges in integrating existing hazard knowledge into governance, planning, and preparedness. Drawing exclusively on published geological, geophysical, engineering, and policy literature, the paper synthesises evidence on seismic hazard, historical earthquake impacts, institutional preparedness, and barriers to the operational use of scientific risk assessments. An integrated, multi-pillar framework is proposed to support improved coordination between science, governance, infrastructure practice, and community preparedness. The framework is conceptual in nature and is intended to inform policy dialogue, prioritisation, and future empirical research rather than to provide a validated operational model. While grounded in the Malawian context, the insights presented are relevant to other low-income, rift-hosted regions facing similar challenges in translating earthquake science into effective disaster risk reduction.

GeoHazards doi: 10.3390/geohazards7020041

Authors: Rhommel N. Grutas Margarita P. Dizon Gilbert A. Ramilo Jeanne Benette P. Pabello Maria Leonila P. Bautista

Prior studies have shown that socio-economic and structural risks can be correlated with earthquake effects. The quantification of these effects was used to formulate robust disaster risk reduction (DRR) strategies and building codes. This is more pronounced in countries with complex tectonic settings, such as the Philippines, where strong-to-major earthquakes can occur. Here, we report the evaluation of deterministic ground shaking (GS) intensity measurements for Camarines Norte, the Philippines, with the objective of assessing and mapping the susceptibility of communities to intense ground motion. GS intensities and peak ground acceleration (PGA) were computed using the Rapid Earthquake Damage Assessment System (REDAS) software developed by the Philippine Institute of Volcanology and Seismology (PHIVOLCS). The PGA was computed as a fraction of acceleration due to gravity, while GS used the PHIVOLCS Earthquake Intensity Scale (PEIS). Simulations were based on recorded earthquakes and mapped active faults near the province. Geographic information systems were used to stack and refine each simulation. Results showed that 13 earthquakes and 13 seismic source zones classified most of the province as PEIS VIII or higher, with the PGA maximum at 0.66 g. The results implied that the province is susceptible to very destructive to completely devastating ground shaking, and it is recommended to incorporate these results into DRR policymaking.

GeoHazards doi: 10.3390/geohazards7020040

Authors: Wenjia Li Yongzhang Zhou

Geohazards such as landslides, earthquakes, debris flows, and floods are governed by complex interactions among geological, hydrological, and human processes. Traditional data-driven models have improved hazard prediction but often lack interpretability and adaptability. This review examines the evolution of knowledge-guided approaches in geohazard research, highlighting how knowledge representation and artificial intelligence have progressively converged to enhance understanding, reasoning, and model transparency. A bibliometric analysis of 1410 publications indexed in the Web of Science reveals an evolution from early ontology-based knowledge engineering for expert reasoning to knowledge graphs (KG), frameworks enabling multi-source data integration and relational inference, and more recently, to large language model (LLM), augmented systems for automated knowledge extraction and cognitive geoscience. This review synthesizes advances in knowledge representation, knowledge graphs, and LLM-based reasoning, demonstrating how hybrid models that embed physical laws and expert knowledge can improve the interpretability and generalization of machine learning. These developments enable new forms of knowledge-driven geohazard intelligence and support applications in hazard monitoring, early warning, and risk communication. There are challenges we still face, including semantic fragmentation, limited causal reasoning, and sparse data for extreme events. Future directions require unified knowledge–data–mechanism architectures, causality-aware modeling, and interoperable standards to advance trustworthy and explainable geohazard intelligence.

GeoHazards doi: 10.3390/geohazards7020039

Authors: Massimo Conforti Olga Petrucci

Rainfall-induced landslides represent one of the most recurrent geohazards affecting the transportation network of southwestern Calabria (Italy). This study provides an integrated assessment of landslide occurrence and road damage along the Costa Viola by combining detailed geomorphological mapping, multi-temporal analyses, historical documentation (1950–2025), and GIS-based spatial data processing. A total of 261 landslides were mapped, affecting approximately 19% of the study area. Slides constitute the dominant movement type (66.7%), followed by complex landslides, flows, and falls. Landslide distribution is strongly controlled by geological and morphometric factors: more than 80% of mapped phenomena occur in highly fractured granitic and gneissic rocks, over 70% lie within 500 m of faults, and more than 90% are located within 300 m of streams. Slope gradient (25–55°) and local relief (350–550 m) further contribute to slope instability patterns. The historical dataset documents 237 landslide-induced road damage events over 75 years, with a marked increase in occurrence since the early 2000s. Most damage events affected the SS18 road and frequently corresponded to reactivations of pre-existing landslides, highlighting the long-term persistence of slope instability and the seasonal influence of intense autumn–winter precipitation. Overall, the results demonstrate that landslide hazard in the Costa Viola is governed by the interplay between structural, lithological, geomorphic, and climatic factors, compounded by anthropogenic modifications along road corridors. The combined landslide inventory and historical database provide a robust basis for risk mitigation, identification of critical road sectors, and future susceptibility and predictive modelling to support effective territorial planning.

GeoHazards doi: 10.3390/geohazards7020038

Authors: Andreas Karakonstantis Vasilis Kapetanidis Nikolaos Madonis Haralambos Kranis George Kaviris

We present an enhanced earthquake catalog for Central Evia and the Northern Gulf of Evia, in Central Greece, between June 2018 and November 2023. The area is characterized by a low background seismicity rate, with occasional clustered events and seismic swarms, including those of February–April 2022 near Drosia and of October 2022 near Styra. The seismic catalog was enhanced by integrating additional data acquired through the application of the EQ-Transformer deep-learning model. A total of ~1400 events were analyzed, with ~1200 of them being successfully relocated with the double-difference method. The available focal mechanisms indicate predominantly normal, oblique-normal, and pure strike-slip faulting. The relocated seismicity was examined in conjunction with known mapped faults to investigate the activated structures at depth, providing insight into their degree of activity. In Drosia, the seismicity, at a depth of ~14 km, can be related to an E–W dextral strike-slip fault, with subtle surficial expression. In Psachna, the epicenters are oriented in an NE–SW direction, not matching the strike of the mainshock’s normal focal mechanism, but roughly coinciding with NE–SW-oriented topographic spurs and the local drainage pattern. In Markates and Prokopi, the seismicity is sparse, but the focal mechanisms are consistent with SW–NE dextral strike-slip faulting, aligned with the trend of the Nileas depression and the Prokopi–Pelion fault zone. Finally, in Mouriki, the seismic cluster is characterized by WNW-ESE normal faulting, most likely related to the SSW-dipping Messapio fault.

GeoHazards doi: 10.3390/geohazards7020037

Authors: Muhammad Rizki Nandika Herlambang Aulia Rachman Martiwi Diah Setiawati Abd. Rahman As-syakur Atika Kumala Dewi La Ode Alifatri Tri Atmaja Takahiro Osawa A. A. Md. Ananda Putra Suardana

Utilizing the InVEST coastal exposure model and multi-source geospatial data, this study evaluates coastal vulnerability to sea-level rise along a critical stretch of the North Coast of Central Java, Indonesia, specifically focusing on the Semarang, Demak, and Jepara regions. A Coastal Exposure Index (CEI) was constructed for 256.63 km of shoreline by integrating key environmental variables, including wave climate, high-resolution coastal topography, shoreline geomorphology, bathymetry, coastal habitat distribution, and observed sea-level rise trends-based satellite altimetry from AVISO. The CEI classified coastal segments into five risk categories from Very Low to Very High exposure. A comparative analysis was performed between a scenario incorporating coastal habitats and a scenario without habitats to determine the protective role of natural ecosystems. The results of the analysis show that the average sea-level rise in the study area is 4.3 mm/year. Moreover, the findings also show that the inclusion of coastal habitats significantly reduces extreme exposure levels. Without accounting for habitats, 22.8% of the coastline was classified as Very High exposure, whereas with habitats included this portion dropped to 1.8%. For example, in Jepara Regency the length of shoreline in Very High exposure class decreased from 53.7% (no habitat scenario) to 5.5% when habitats were considered. Overall, the presence of coastal ecosystems shifted large stretches of the coast to lower exposure classes. This study demonstrates that natural habitats have a critical influence on coastal exposure, substantially mitigating the vulnerability of North Java’s coastline to sea-level rise.

GeoHazards doi: 10.3390/geohazards7010036

Authors: Kevin Potoczny Katsuichiro Goda Abouzar Sadrekarimi

Landslide hazard potential is high across the St. Lawrence lowlands of Québec, Canada, due to sensitive glaciomarine clay deposits and the presence of moderate seismic activity, causing slope failures in the region. The main objectives of the study are to develop a working database for landslides in the region and use that database to improve regional landslide susceptibility analysis. Using high-resolution (1 m by 1 m cells) digital terrain models dated from 2009 and validated with satellite photogrammetry from 2012, a landslide inventory of 263 cases related to the 2010 Val-des-Bois earthquake (moment magnitude 5.0) is created. Relationships between landslide susceptibility factors, such as slope angle, and seismic conditioning factors, such as peak ground acceleration, are examined through machine learning methods. For landslide detection, an overall accuracy of approximately 85% (AUC 0.914) is achieved using random forest and logistic regression models cross-validated through 5-fold analysis, showing improvement over the currently employed Hazus method, which achieves an accuracy of approximately 67%. From a regional perspective, the developed inventory and resultant susceptibility models are unique and form the foundation for future studies to improve the understanding of earthquake-induced landslides in the Western Québec Seismic Zone, which historically lacks detailed landslide inventories.

GeoHazards doi: 10.3390/geohazards7010035

Authors: Adnan Ahmed Abi Sen Fares Hamad Aljohani Nour Mahmoud Bahbouh Adel Ben Mnaouer Omar Tayan Ahmad. B. Alkhodre

Smart cities require effective disaster management (like flooding, solar storms, sandstorms, or hurricanes), as it directly impacts people’s lives. The key challenges of disaster management are timely detection and effective notification during the crisis. This research presents a smart multi-layer framework for notification classification and management before and during flooding disasters. The framework includes an early detection module as the main phase in the alerting process. This step depends on an Ensemble Learning (EL) model based on a triad of the three best selected models (Deep Learning (DL), Random Forest (RF), and K-nearest Neighbor (KNN)) to analyze data collected continuously from the Internet of Things (IoT) layer. In the boosting phase, the framework utilizes Large Language Models (LLMs) with DL to analyze social textual crowdsourcing data. The results will enable the framework to identify the most affected areas during a flood. The framework adds a fog computing layer alongside a cloud layer to enable instantaneous processing of user responses and generate specialized alerts based on contextual factors such as location, time, risk level, alert type, and user characteristics. Through testing and implementation, the proposed algorithms demonstrated an accuracy rate of over 98% in detecting threats using a dataset of real, collected weather and flooding data. Additionally, the framework proposes a centralized control panel and a design of a smartphone application that offers essential services and facilitates communication among managed civil defense teams, citizens, and volunteers.

GeoHazards doi: 10.3390/geohazards7010033

Authors: Károly Németh Abdulrahman Sowaigh Mahmoud Ashor Mostafa Toni Vladimir Sokolov

Saudi Arabia is experiencing interactions between ongoing urbanization, tourism growth, infrastructure projects in western regions along the Red Sea, and volcanic hazards. The area contains extensive monogenetic volcanic fields with hundreds of volcanoes formed during the Quaternary period. The large scale of the region often limits and fragments volcanological research, resulting in insufficient age and chemical data to understand the spatial and temporal development of many volcanic fields. Increased tourism has created a need for volcanic hazard assessments, particularly since some volcanic fields are considered possible tourist destinations. Harrat Lunayyir, in northwestern Saudi Arabia, is an example where such assessments have been conducted. Hazard assessments seek to provide information about potential future eruption types, locations, and impacts over timeframes relevant to urban planning and risk management. Due to rapid local development, these assessments may be required on short notice for specific small areas within larger volcanic fields, even when geological data are limited. This report presents a deterministic, scenario-based method for addressing such requests in the Lunayyir Volcanic Field. Results indicate a young Holocene eruption site characterized by a complex scoria cone associated with lava spattering, Strombolian, violent Strombolian activity and extensive transitional-type lava effusion.

GeoHazards doi: 10.3390/geohazards7010034

Authors: Zeinab Bayati Arash K. Pour Ali Saeidi Ehsan Noroozinejad Farsangi

This study evaluates the stability of slopes supported by mechanically stabilized earth walls under combined hydrostatic and seismic loading conditions. Limit equilibrium, pseudo-static methods and permanent displacement approaches, including the Newmark rigid block method as well as coupled and decoupled techniques, are employed to assess the static and seismic performance of the soil slope under investigation. Parametric analyses are conducted using the Slide2 software package (Version 9.041) and verified against geotechnical design criteria to examine the effects of groundwater level and seismic intensity on factors of safety, failure mechanisms, and seismic-induced displacements of the slope. Results based on multiple strong ground motion records indicate that elevated water tables and hydrostatic pressures behind the wall, up to levels near the wall toe, do not significantly increase the failure potential or slope displacement. This behavior is attributed to the MSE wall acting as a rigid stabilizing system that enhances overall slope stability.

GeoHazards doi: 10.3390/geohazards7010032

Authors: Ioannis Grendas Nikolaos Theodoulidis

In the 20th century, several large-magnitude earthquakes (M > 7.0) occurred in Greece and surrounding areas, some of which caused extensive structural damage and significant loss of life. Unfortunately, for these earthquakes, there was no recorded ground motion intensity data to extract information about the macroseismic intensity distribution within the affected areas. A characteristic example of such an earthquake is the M7.2 of 12 August 1953 on Cephalonia island, which led to the almost complete destruction of settlements across the Cephalonia, Zakynthos, and Ithaca islands in western Greece. Although the vulnerability of the buildings affected in 1953 substantially differs from modern structures, the intensity and spatial extent of the shaking indicate that an event of similar magnitude could, even today, place the built environment and critical infrastructure of the region at high seismic risk. This study aims to estimate peak ground acceleration and velocity (PGA–PGV) and macroseismic intensity for the Cephalonia, Zakynthos, and Ithaca islands associated with earthquake scenarios comparable to the 1953 event (M7.2), incorporating seismotectonic information about active faults linked to the historical earthquake and considering associated uncertainties. Ground motion prediction models recently developed for Greece are employed. High PGA values (0.41–0.44 g) are estimated for the M7.2 earthquake, for rock site conditions (Vs30 ≥ 790 m/s), covering almost the entire island of Cephalonia; these can be considered as the minimum values expected on rock site conditions for a similar earthquake scenario.

GeoHazards doi: 10.3390/geohazards7010031

Authors: Gumbert Maylda Pratama Takashi Gomi Rozaqqa Noviandi Rasis Putra Ritonga Teuku Faisal Fathani Wahyu Wilopo

Tropical mountain watersheds contain heterogeneous land cover and land use (LCLU) mosaics, yet the relationship between these mosaics and landslide morphometry and occurrence at the watershed scale remains unclear. We compiled landslide inventory from 2002 to 2023 for the 152.3 km2 Upper Ciliwung Watershed, West Java, Indonesia. We mapped morphometry for a subset of 84 landslides, classified the events into seven LCLU classes, and compared landslide size–frequency distributions across vegetation groups. Principal component analysis (PCA) revealed that LCLU type influences landslide size and mobility. Forested terrain produced narrower, longer-runout landslides on steeper slopes, whereas agricultural and other herbaceous-dominated terrain generated wider landslides on gentler slopes. Clarifying landslides by vegetation characteristics as either tree- or herbaceous-dominated areas (including urban areas) revealed distinct size–frequency patterns, especially for small landslides (tree-dominated: 133 m2, herbaceous-dominated and other: 97 m2; overall 112 m2), which are consistent with the contrasting vegetation structures and hydrological responses. PCA supported these patterns, with PC1 describing a morphometric axis and PC2 capturing gradients in event rainfall and antecedent wetness. Together, these results support the conclusion that vegetation structure and land-use conditions influence slope stability by affecting soil reinforcement and hydrological responses. This provides a foundation for land–use–specific geohazard mitigation and vegetation-based slope stability planning.

GeoHazards doi: 10.3390/geohazards7010030

Authors: Noureddine Dael Gouem Sepehr Saedi Mohsen Seyedi

Earthfill dams located in seismic regions are highly vulnerable to earthquake-induced deformations, particularly when founded on soft alluvial soils. This study presents a comparative numerical investigation of earthfill dams with asphalt and clay cores subjected to seismic loading. A 20 m-high zoned embankment dam founded on soft alluvial deposits was modeled in PLAXIS2D and subjected to four earthquake records. The dynamic responses at the crest and downstream slope were evaluated in terms of acceleration, settlement, and lateral displacement. The results indicate that while lateral displacements are nearly identical for both core types, dams with clay cores experience significantly higher seismic settlements, reaching up to 35% more than those with asphalt cores under strong earthquake loading. Overall, the asphalt core demonstrated enhanced resilience, exhibiting reduced settlement due to its higher stiffness, viscoelastic behavior, and inherent capacity for self-healing following seismic loading.

GeoHazards doi: 10.3390/geohazards7010027

Authors: Joaquín Raul Rodríguez Erik Esteban Ramírez Mario González-Durán

Mexicali, capital of Baja California, has 1,049,792 inhabitants and lies in a high-seismic-hazard zone in northwestern Mexico, according to CENAPRED, the MDOC-CFE-2015 seismic regionalization, and the ASCE 7-22 “Hazard Toolkit”. This study develops a probabilistic seismic hazard map to estimate peak ground accelerations with a 2% probability of exceedance in 50 years, using the OpenQuake platform. The study area coincides with the 2025 urban development plan polygon for the central population area defined by the Municipal Institute for Research and Urban Planning of Mexicali. The Imperial and Cerro Prieto faults, the Pescaderos–Indiviso fault system, and the Laguna Salada fault were modeled as seismic sources. Four PEER-NGA ground motion prediction equations and regional geophysical and geotechnical data were employed to characterize shear-wave velocity (Vs30). Design response spectra were generated for each grid point for the 21 periods specified in ASCE 7-22. A representative Vs30 of 236 m/s was obtained, and the a, b, and Mc parameters were derived for the seismic catalog. Resulting peak ground accelerations range from 0.842 g to 1.221 g, with a maximum spectral pseudo-acceleration of 2.23 g at 0.30 s.

GeoHazards doi: 10.3390/geohazards7010029

Authors: Essi Nadège Parkoo Kossi Adjonou Atsu K. Dogbeda Hlovor Afi Amen Christèle Attiogbé Kossi Komi Kodjovi Senanou Gbafa Kouami Kokou

The Upper Mono Basin Valley (UMBV) in Togo faces recurrent flooding hazards. This study assesses spatial flood susceptibility using an integrated approach combining Geographic Information Systems (GISs), Multi-Criteria Decision Making (MCDM), and the Analytic Hierarchy Process (AHP). Eight factors were weighted according to their influence: accumulation flow, annual precipitation, soil permeability, land use/land cover, slope, elevation, distance from drainage networks, and drainage network density. With a consistency ratio of 0.052, the AHP method proved coherent and enabled the development of a normalized Flood Hazard Index (FHI). Results revealed accumulation flow (weight = 0.33), distance to drainage networks (0.18), and network density (0.16) as the most critical drivers, while precipitation and soil permeability are secondary. Spatial classification revealed heterogeneity: 55% (871,046 ha) of the UMBV has very low susceptibility, while 1% (10,034 ha) is highly vulnerable, mainly in Est-Mono, Ogou, Anié, Tchamba, and Tchaoudjo. In contrast, Blitta and Sotouboua show lower vulnerability due to higher altitudes. This reveals that the UMBV is relatively less prone to flooding. The comparison of data from 28 focus groups in 14 municipalities with the flood susceptibility map shows a strong concordance between local perceptions and the mapping (r = 0.805, p < 0.001). These findings highlight the need for differentiated territorial strategies integrating physical parameters, land use dynamics, and community risk perceptions to strengthen flood risk management in the UMBV.

GeoHazards doi: 10.3390/geohazards7010028

Authors: Robert E. Kayen

The 1964 M7.5 Niigata earthquake remains one of the most significant natural laboratories for understanding seismic–induced soil liquefaction and its dependence on geological setting. Among global field case histories, Niigata stands out for the exceptional documentation of liquefaction triggering, lateral spread displacements, and soil–structure interaction. This paper reexamines the event from an engineering–geologic perspective, emphasizing how Holocene coastal and fluvial depositional processes beneath the Echigo Plain controlled the spatial and stratigraphic distribution of liquefaction during the 1964 earthquake. The most severe ground deformations occurred in fluvially reworked sands derived from three major Holocene dune and barrier island systems (CSD1,2,3) formed along the paleo–shoreline of the Sea of Japan. The largest of these, a mid–Holocene transgressive barrier complex deposited to a thickness of 50–60 m of beach and aeolian sand between 8 and 5 ka B.P., now lies buried 5–8 km inland beneath fine–grained alluvial deposits. Tectonic downwarping and deltaic progradation by the Shinano and Agano rivers redistributed these sands into loose, saturated fluvial facies beneath modern Niigata city. Quantitative geotechnical analyses demonstrate that liquefaction occurs within these reworked Holocene units rather than anthropogenic fills.

GeoHazards doi: 10.3390/geohazards7010026

Authors: Emmanuel Zúñiga Enrique Pérez-Campuzano

Mexico City (CDMX) is located in an endorheic basin historically prone to flooding and waterlogging, the recurrence and magnitude of which have intensified in recent decades. However, flood risk assessment tends to focus primarily on the occurrence of intense rainfall to explain this phenomenon. The main objective of this study is to demonstrate that the risk of flooding in Mexico City (CDMX) depends not only on intense rainfall, but also on changes in hydrological vulnerability resulting from the loss of natural vegetation cover. The curve number (CN) method is used to determine hydrological vulnerability and flood risk in CDMX, integrating environmental information and precipitation values. Changes in surface runoff are also determined for 10 watersheds located west of Mexico City, considering urbanization in 1992 and 2021, as well as a non-urbanized scenario. The results indicate that hydrological vulnerability and flood risk increased from acceptable levels to “high” and “very high” levels, mainly in regions where urbanization increased and natural vegetation decreased. It was also identified that, under different levels of precipitation, agricultural and urban land cover have considerably lower infiltration capacities compared to natural land cover, such as forests, which infiltrate more than half of the precipitation. Finally, the increase in surface runoff in the watersheds located west of the city is closely related to the urbanization process and the physical characteristics of the territory. It was also observed that a degraded watershed can generate approximately 90% more runoff than a non-urbanized watershed.

GeoHazards doi: 10.3390/geohazards7010025

Authors: José Luis Pérez-García José Miguel Gómez-López Antonio Tomás Mozas-Calvache Diego Vico-García

Precise modeling of narrow gorges is challenging due to extreme confinement, hindering visibility and accessibility. These environments often render Global Navigation Satellite Systems (GNSS)-based positioning unfeasible, a difficulty compounded by water and dense vegetation. Consequently, multi-technique data fusion is required. This study proposes a robust methodology to generate high-resolution 3D models of such complex environments by integrating multiple aerial (e.g., Unmanned Aerial Vehicles, UAVs) and terrestrial techniques. A multi-sensor approach combined UAV-Light Detection and Ranging (LiDAR) and UAV-photogrammetry for external areas with Terrestrial laser scanning (TLS), Mobile Mapping System (MMS), and Spherical Photogrammetry (SP) for the canyon floor. Furthermore, the representativeness of these 3D models was analyzed against standard Digital Terrain Models (DTMs) for determining water height levels during flood events. A one-dimensional hydraulic (1DH) model compared the 3D mesh approach with the traditional 2.5D perspective in a challenging, narrow canyon prone to flooding. Our results show that traditional 2.5D DTMs significantly over- or underestimate water levels in narrow sections—failing to account for overhangs and vertical wall irregularities—whereas high-resolution 3D meshes provide a more realistic representation of hydraulic behavior. This work demonstrates that multi-sensor data fusion is essential for accurate flood risk management and infrastructure planning in complex fluvial environments.

GeoHazards doi: 10.3390/geohazards7010024

Authors: Mohammad Reza Yeganegi Nadejda Komendantova

Building resilience is largely affected by the socioeconomic characteristics of the community as well as the physical and environmental local characteristics. The effectiveness of the adopted policies for resilience building partly relies on considering public concerns and insights. Insights from public narratives can enrich the resilience-building policies by sharing experiences or evidence from past disasters. Furthermore, it reveals priorities and concerns that society is expecting to be addressed. Even if the concerns are triggered by misinformation, addressing them (e.g., by disseminating corrective information) can increase the success of resilience-building policies. Tracing the public narrative over time shows how much people’s perspectives have changed after the disaster and how the relief and resilience-building efforts were compatible with society’s expectations. This study is aimed at extracting such insights from the public narrative on social media platforms after Morocco’s 2023 earthquake.

GeoHazards doi: 10.3390/geohazards7010023

Authors: Irshad Ali Zardari Ningsheng Chen Surih Sibaghatullah Jagirani Shufeng Tian Rosette Niyirora

A dam breach is an uncommon but profoundly destructive event that transpires when a dam collapses, releasing accumulated water downstream and leading to extensive damage. This study focuses on the Jure landslide dam, located in the Sindhupalchowk district, Nepal. The region is characterized by complex river channels and steep terrains, which are significantly influenced by flood dynamics. This study aims to establish a compressive numerical simulation of a two-dimensional dam breach unsteady flow hydraulic model to simulate the dam breach process and downstream flood propagation. The study analyzes the dynamics of the Jure landslide dam outburst flood, emphasizing the flood characteristics, inundation, and velocity hazards in the mitigation of flood impacts. The results reveal that the peak discharge of the Jure landside dam was 5336.7 m3/s, while it decreased to 1181.4 m3/s when traveling 35 km. The flood depth obtained by 2D (HEC-RAS) downstream of the dam rages between 0.0334 and 55.9 m, while the corresponding estimated peak flow velocity of simulated breaches was 21.46 m/s, demonstrating extreme hydraulic force conditions, capable of catastrophe. The proposed hydraulic simulations reveal significant variations in overflow dynamics across different terrain types, with narrower sections exhibiting faster flood progression and greater water depths. The findings underscore the necessity of accounting for terrain heterogeneity in future flood risk assessments. This work offers valuable insights into the emergency management of landslide dams in similar regions.

GeoHazards doi: 10.3390/geohazards7010022

Authors: Constantin D. Athanassas Vassiliki Kanavou Regis Braucher Ioannis Vakalas Ioannis Ladas Katerina Theodorakopoulou Harris Zampoukos

This work deals with the quantification of long-term fault slip rates as a basis for seismic hazard assessment along a segment of the Eastern Messinia Fault Zone (EMFZ) in southwestern Peloponnese, Greece. Using cosmogenic 36Cl exposure dating, it provides independent numerical constraints on recent deformation. The resulting late Holocene slip-rate estimates (~0.32–0.46 mm/yr) confirm ongoing fault activity, consistent with earlier paleoseismological and geomorphic studies, while indicating spatially distributed extension. These rates imply loading timescales of several hundred years for moderate (Mw ≈ 5.8–6.0) earthquakes. Although individual exposure ages cannot be uniquely associated with single seismic events, they offer robust benchmarks for cumulative displacement and long-term strain accumulation. Overall, this work demonstrates how numerical dating methods (particularly cosmogenic nuclide techniques applied to carbonate bedrock) can link geological observations with engineering requirements by constraining fault behavior over 103–105 year timescales and improving long-term seismic hazard evaluation in complex tectonic settings.

GeoHazards doi: 10.3390/geohazards7010021

Authors: Mikayel Gevorgyan Dmitri Arakelyan Hayk Igityan Hayk Baghdasaryan Hektor Babayan Gevorg Babayan Suren Arakelyan Khachatur Meliksetian Elya Sahakyan

The territory of the Republic of Armenia (RA) lies within the central Arabia–Eurasia collision zone and is characterized by rugged mountain landscapes, complex geology, active faulting, and seismicity. Armenia is highly vulnerable to seismic and landslide hazards, with more than 2504 active landslides mapped in the country. A significant landslide in the Tumanyan Community, Lori Marz, was activated in January 2018 and threatened critical infrastructure, including the railway linking Armenia to Georgia and the M6 interstate highway. The landslide’s activation was driven by groundwater, a nearby water reservoir leak, and adjacent infrastructure. Preliminary hazard analysis revealed that further movement of the landslide could dam the Debed River, leading to potentially catastrophic downstream impacts. In response, the Minister of Emergency Situations of RA requested urgent studies by the Institute of Geological Sciences of NAS RA. Surveys began on 22 January 2018, involving an interdisciplinary approach including geotechnical study, UAV-based digital mapping, and application of geophysical methods, such as MASW, microtremor recordings, GPR, and VES. The combination of these methods provided reliable information on the landslide’s geotechnical structure, identified the sliding plane, and allowed for numerical slope stability modeling, which confirmed the landslide’s unstable condition and susceptibility to reactivation from earthquakes or elevated groundwater. Based on this complex research, protective measures were developed and applied, including, in particular, horizontal drilling to dewater the sliding plane. These emergency measures stabilized the landslide, mitigating immediate threats to infrastructure and ensuring relative safety.

GeoHazards doi: 10.3390/geohazards7010020

Authors: Javedullah Hemat Sherzai Yoshiya Igarashi Norio Tanaka Hokuto Kato Takuma Takeda

Levee overtopping poses a significant risk to flood defense infrastructure by inducing severe erosion and scour, particularly along the landward slope and toe regions. This study investigates the effectiveness of an integrated protection system combining seamless cement coating with strategically placed H-type piles to mitigate scour and modify flow dynamics under prolonged overflowing. A series of physical model tests were conducted to evaluate full and partial concrete slope protection with and without pile integration. Results showed that the seamless concrete revetment significantly delayed slope failure, resisted joint-related seepage, acted as a rigid cantilever, and maintained the structural integrity despite surrounding erosion. The inclusion of emergent H-type piles at the downstream toe disrupted the overflow jet, enhanced early energy dissipation, and reduced scour dimensions. The FC + P_ES (fully coated with emergent piles) configuration exhibited the strongest performance, reducing downstream scour length by 40%, upstream extent by 66.7%, and maximum scour depth by 7.7% compared to the FC_NP (fully coated, no-piles) condition. Partial slope coverage combined with emergent piles delayed scour initiation by approximately threefold, highlighting the synergistic effect of combined surface and flow-deflected structures measures. Conversely, bed-level piles redirected jet energy beneath the surface layer, intensifying vertical scour and upstream erosion, indicating the critical importance of pile placement and elevation. The findings emphasize the importance of integrating seamless surface protection with vertical flow disrupters to effectively manage flow-induced erosion and enhance levee resilience against overtopping floods. This hybrid approach offers a practical solution for flood-prone riverine levee systems.

GeoHazards doi: 10.3390/geohazards7010019

Authors: Qianhao Tang Stephen Akosah Ivan Gratchev Jeung-Hwan Doh

This paper presents a systematic review of research investigating the effects of elevated temperatures on sedimentary rocks. The literature was selected using keyword-based searches of titles, abstracts, and keywords in the Scopus and Web of Science databases. In total, 107 relevant articles published between 2010 and 2024 were critically examined to address research questions on temperature-treated sedimentary rocks. Furthermore, both bibliometric analysis and systematic synthesis of experimental data were performed. The review identifies sandstone as the most-studied rock type, followed by limestone. It reveals that standard experimental methods include unconfined compressive strength (UCS), Brazilian tensile strength (BTS), and P-wave velocity tests. The study’s findings indicate that a temperature threshold of 400–600 °C governs deterioration in engineering properties, driven by the quartz α–β transition in sandstones and calcite decomposition in limestones. Normalized data show that UCS, BTS, and elastic modulus decline significantly beyond this threshold, while porosity increases. The study highlights the influence of fabric anisotropy, mineralogy, and heating conditions on rock behaviour, and identifies research gaps related to confined testing, real-fire scenarios, and anisotropic rocks. Based on a comprehensive analysis of the literature, the principal factors and processes occurring at different temperature ranges were identified and discussed.

GeoHazards doi: 10.3390/geohazards7010018

Authors: Olha Orlinska Dmytro Pikarenia Leonid Rudakov Hennadii Hapich

Uranium production tailing ponds in Kamyanske (Ukraine) are objects of increased radioecological danger. Violation of the stability and integrity of containment dams threatens the uncontrolled spread of radionuclides. The purpose of this study is to comprehensively assess the factors affecting the technical condition and environmental safety of the Sukhachivske tailing dam. The study included a visual inspection and detailed geophysical work using the natural pulse electromagnetic field of the Earth (NPEMFE) method. This method was chosen to identify hidden filtration paths and stress zones in the body of the earth dam. An analysis of the spatial distribution of waterlogging, filtration, and fissuring in the hydraulic structure was performed. Based on the results of the NPEMFE survey, six zones with varying degrees of waterlogging and stress–strain states of the structure were identified. The presence of externally unmanifested filtration paths and suffusion areas was established, and a tectonic scheme of fracture development in the dam body was compiled. A correlation was found between the dominant azimuths of crack extension (70–79° and 350–359°) and the directions of regional tectonic lineament zones, at the intersection of which the tailing pond is located. It has been established that modern tectonic movements along fault zones create zones of permeability, which serve as primary pathways for water filtration and further development of suffusion. This conclusion introduces a new tectonic feature for risk diagnosis and monitoring of similar hydraulic structures.

GeoHazards doi: 10.3390/geohazards7010017

Authors: Menghao Li Yichen Zhang Jiquan Zhang Zhou Wen Jintao Huang Haoying Li

Ground subsidence in mined-out areas has irreversible impacts on residents’ lives and infrastructure, making its monitoring and prediction crucial for ensuring safety, protecting the ecological environment, and promoting sustainable development. This study employed the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to process Sentinel-1A satellite images of Liaoyuan’s Northern New District from August 2022 to March 2025, deriving ground deformation data. The SBAS-InSAR results were validated using unmanned aerial vehicle (UAV) measurements. Monitoring revealed deformation rates ranging from −26.80 mm/year (subsidence) to 13.12 mm/year (uplift) in the area, with a maximum cumulative subsidence of 59.59 mm observed near the Xi’an Sixth District. Based on spatiotemporal patterns, most mining-induced subsidence in the study area is in its late stage, primarily caused by progressive compaction of fractured rock masses and voids within the collapse and fracture zones. Using subsidence data from August 2022 to March 2024, three prediction models—LSTM, GRU, and TCN-GRU—were trained and subsequently applied to forecast subsidence from March 2024 to August 2025. Comparisons between the predictions and SBAS-InSAR measurements showed that all models achieved high accuracy. Among them, the TCN-GRU model yielded predictions closest to the actual values, with a correlation coefficient exceeding 0.95, validating its potential for application in time-series settlement monitoring.

GeoHazards doi: 10.3390/geohazards7010016

Authors: Giovanni Scapellato Giuseppe Licciardello Giuseppe Lorenzo Maria Blanco Francesco Campione Maria Letizia Carbone Salvatore Castorina Antonio Mirko Londino Mariangela Riggio Giuseppe Sapienza Giuseppe Scrofana Salvatore Tomarchio Salvatore Scalia Marco Neri

Post-disaster reconstruction requires instruments capable of ensuring procedural consistency, administrative transparency, and the systematic integration of geohazards, all of which are essential for safeguarding communities. This study presents the digital platform established under Italian Law 55/2019 for the reconstruction of the areas on Mt. Etna affected by the Mw 4.9 earthquake of 26 December 2018, emphasizing its innovative contribution to current international approaches to reconstruction governance. The platform standardizes the entire administrative workflow and is centered on the Parametric Form, which enables an objective calculation of eligible reconstruction grants based on damage indicators, vulnerability metrics, and parametric cost functions. A defining feature of the Etna model is the structural integration between administrative procedures and geohazard mitigation, achieved through updated hazard maps and protocols that incorporate geological, hydrogeological, and geomorphological conditions. This approach reframes reconstruction as an opportunity to reduce overall territorial vulnerability. The system also includes public monitoring tools (WebGIS and dashboards) that enhance traceability, compliance, and stakeholder engagement. Expected outcomes include shorter administrative timelines, improved interinstitutional coordination, and the potential transferability of the model to other emergency contexts. In comparison with international cases, the Etna experience represents an original integration of digitalization, parametric assessment, and site-specific hazard mitigation.

GeoHazards doi: 10.3390/geohazards7010015

Authors: Chandra Shekhar Dwivedi Suryaprava Das Arvind Chandra Pandey Bikash Ranjan Parida Sagar Kumar Swain Navneet Kumar

Landslides are a persistent hazard in the tectonically active Central Himalaya, frequently affecting roads and settlements. However, quantitative assessments of their spatial drivers have remained limited. This study investigated landslide susceptibility along a 90 km section of the Uttarkashi–Gangotri highway to identify dominant triggering factors and generate a reliable risk map. We applied the AHP–GIS framework, guided by a multi-criteria decision-making approach. Nine thematic parameters, such as slope, geology, lineament density, drainage density, proximity to roads, rainfall, aspect, curvature, and land use/land cover were utilised to quantify their relative influence on slope failure. Results showed that slope (23%), geology (22%), and lineament density (21%) were the most influential factors. Secondary contributions came from drainage density (9%), proximity to roads (8%), and rainfall (>231 mm). The susceptibility map was validated using 105 landslide inventory points, with 64 events (61%) located in very high-risk zones and 31 (30%) in high-risk zones. The model achieved a predictive accuracy of 0.817 based on the Area Under the Curve (AUC) metric. High-risk zones are aligned with steep slopes (30–50°), convex curvatures, and barren land, particularly near infrastructure. These findings provide a scientific tool for hazard mitigation and support disaster risk reduction in similar mountainous regions worldwide, contributing to safer infrastructure development.

GeoHazards doi: 10.3390/geohazards7010014

Authors: Michalis Diakakis Petros Andriopoulos Andromachi Sarantopoulou Ioannis Kapris Christos Filis Aliki Konsolaki Emmanuel Vassilakis Panagiotis Nastos

As the frequency and severity of extreme weather events may increase due to climate change, understanding their impacts on water systems, resources, and infrastructure becomes very important. This study contributes to the growing body of knowledge on how extreme storms and floods disrupt interrelated elements comprising water systems by examining the case of Storm Daniel, which struck the Thessaly region of Greece in September 2023. Using a multi-source approach, including field data, institutional reports, scientific assessments, and publications, the study systematically identifies and categorizes the impacts of the storm and the ensuing flood across surface waters, drinking water supply, and wastewater infrastructure and other water-related systems through various mechanisms. The findings provide an overview of how such extreme storms may affect such systems and reveal widespread, interconnected disruptions that highlight systemic vulnerabilities in both natural and engineered systems, synthesizing these impact pathways. The study presents evidence of poor resilience against extreme events and climate change hazards in water-related infrastructure.

GeoHazards doi: 10.3390/geohazards7010013

Authors: Xiangshen Chen Chao Li Feng Ding Yongju Shao

Freeze–thaw cycles (FTCs) are a prevalent weathering process that threatens the stability of canal slopes in seasonally frozen regions. This study combines direct shear tests under multiple F-T cycles with coupled thermo-hydro-mechanical numerical modeling to investigate the failure mechanisms of slopes with different moisture contents (18%, 22%, 26%). The test results quantify a marked strength degradation, where the cohesion decreases to approximately 50% of its initial value and the internal friction angle is weakened by about 10% after 10 freeze–thaw cycles. The simulation reveals that temperature gradient-driven moisture migration is the core process, leading to a dynamic stress–strain concentration zone that propagates from the upper slope to the toe. The safety factors of the three soil specimens with different moisture contents fell below the critical threshold of 1.3. They registered values of 1.02, 0.99, and 0.78 within 44, 44, and 46 days, which subsequently induced shallow failure. The failure mechanism elucidated in this study enhances the understanding of freeze–thaw-induced slope instability in seasonally frozen regions.

GeoHazards doi: 10.3390/geohazards7010012

Authors: Shane Orchard Aubrey Miller Pascal Sirguey

This study investigates flooding and erosion impacts and human responses in Aoraki Mount Cook and Westland Tai Poutini national parks in Aotearoa New Zealand. These fast-eroding landscapes provide important test cases and insights for considering the public access dimensions of climate change. Our objectives were to explore and characterise the often-overlooked role of public access as a ubiquitous concern for protected areas and other area-based conservation approaches that facilitate connections between people and nature alongside their protective functions. We employed a mixed-methods approach including volunteered geographic information (VGI) from a park user survey (n = 273) and detailed case studies of change on two iconic mountaineering routes based on geospatial analyses of digital elevation models spanning 1986–2022. VGI data identified 36 adversely affected locations while 21% of respondents also identified beneficial aspects of recent landscape changes. Geophysical changes could be perceived differently by different stakeholders, illustrating the potential for competing demands on management responses. Impacts of rainfall-triggered erosion events were explored in case studies of damaged access infrastructure (e.g., roads, tracks, bridges). Adaptive responses resulted from formal or informal (park user-led) actions including re-routing, rebuilding, or abandonment of pre-existing infrastructure. Three widely transferable dimensions of public access management are identified: providing access that supports the core functions of protected areas; evaluating the impacts of both physical changes and human responses to them; and managing tensions between stakeholder preferences. Improved attention to the role of access is essential for effective climate change adaptation in parks and reserves.

GeoHazards doi: 10.3390/geohazards7010011

Authors: Dinara Talgarbayeva Andrey Vilayev Tatyana Dedova Oxana Kuznetsova Larissa Balakay Aibek Merekeyev

Monitoring the stability of hydraulic structures such as dams and reservoirs in seismically active regions is essential for ensuring their safety and operational reliability. This study presents a comprehensive geospatial approach combining lineament analysis and geodynamic zoning to assess the structural stability of the Voroshilov and Priyut reservoirs located in the Almaty region, Kazakhstan. A regional lineament map was generated using ASTER GDEM data, while ALOS PALSAR data were used for detailed local analysis. Lineaments were extracted and analyzed through automated processing in PCI Geomatica. Lineament density maps and azimuthal rose diagrams were constructed to identify zones of tectonic weakness and assess regional structural patterns. Integration of lineament density, GPS velocity fields, InSAR deformation data, and probabilistic seismic hazard maps enabled the development of a detailed geodynamic zoning model. Results show that the studied sites are located within zones of low local geodynamic activity, with lineament densities of 0.8–1.2 km/km2, significantly lower than regional averages of 3–4 km/km2. GPS velocities in the area do not exceed 4 mm/year, and InSAR analysis indicates minimal surface deformation (<5 mm/year). Despite this apparent local stability, the 2024 Voroshilov Dam failure highlights the cumulative effect of regional seismic stresses (PGA up to 0.9 g) and localized filtration along fracture zones as critical risk factors. The proposed geodynamic zoning correctly identified the site as structurally stable under normal conditions but indicates that even low-activity zones are vulnerable under cumulative seismic loading. This demonstrates that an integrated approach combining remote sensing, geodetic, and seismic data can provide quantitative assessments for dam safety, predict potential high-risk zones, and support preventive monitoring in tectonically active regions.

GeoHazards doi: 10.3390/geohazards7010010

Authors: Duo Chu Linshan Liu Zhaofeng Wang

Catastrophic mass flows originating from the high mountain cryosphere often cause cascading hazards. With increasing human activities in the alpine region and the sensitivity of the cryosphere to climate warming, cryospheric hazards are becoming more frequent in the mountain regions. Monitoring the evolution and impact of the glaciers and ice-rock avalanches and hazard consequences in the mountain regions is crucial to understand nature and drivers of mass flow process in order to prevent and mitigate potential hazard risks. In this study, the glacier and ice-rock avalanches that occurred in the Tibetan Plateau (TP) were investigated based on the Sentinel-2 satellite data and in situ observations, and the main driving forces and impacts on the regional environment, landscape, and geomorphological conditions were also analyzed. The results showed that the avalanche deposit of Arutso glacier No. 53 completely melted away in 2 years, while the deposit of Arutso glacier No. 50 melted in 7 years. Four large-scale ice-rock avalanches in the Sedongpu basin not only had significant impacts on the river flow, landscape, and geomorphologic shape in the basin, but also caused serious disasters in the region and beyond. These glacier and ice-rock avalanches were caused by temperature anomaly, heavy precipitation, climate warming, and seismic activity, etc., which act on the specific glacier properties in the high mountain regions. The study highlights scientific advances should support and benefit the remote and vulnerable mountain communities to make mountain regions safer.

GeoHazards doi: 10.3390/geohazards7010009

Authors: Ayla Ocak Sinan Melih Nigdeli Gebrail Bekdaş Zong Woo Geem

The optimization of seismic isolation parameters is essential for balancing displacement demand and acceleration control in base-isolated structures. While numerous studies have applied metaheuristic algorithms to isolator tuning, the influence of objective-function weighting on optimal design outcomes remains insufficiently explored. This study investigates the effects of displacement and acceleration on control performance in a multi-objective optimization function. Thus, acceleration can be reduced economically by limiting the isolator displacement capacity. In the study, the effective values of the acceleration and displacement coefficients in the objective function of the problem are changed for the design optimization of seismic base isolators, and the determination of the most appropriate weights in the equation and their effects on the control are investigated. In the optimization process, the adaptive harmony search algorithm, which is obtained by adapting the parameters of the harmony search algorithm inspired by the search for the best harmony, is used. The results demonstrate that increased emphasis on acceleration minimization leads to longer effective isolation periods and higher damping ratios, whereas displacement-dominated weighting results in stiffer isolation systems with reduced mobility.

GeoHazards doi: 10.3390/geohazards7010008

Authors: Pouyan Abbasimaedeh

This study presents a validated numerical investigation into the seismic liquefaction potential of fine-grained reclaimed sediments commonly encountered in coastal, containment, and reclamation projects. Fine-grained reclaimed sediments pose a particular challenge for seismic liquefaction assessment due to their low permeability, high fines content, and complex cyclic response under earthquake loading. A fully coupled, nonlinear finite element model was developed using the Pressure-Dependent Multi-Yield (PDMY) constitutive framework, calibrated against laboratory Cyclic Direct Simple Shear (CDSS) tests and verified using in situ Cone Penetration Tests with pore pressure measurement (CPTu). The model effectively captured the dynamic response of saturated sediments, including excess pore pressure generation, cyclic mobility, and post-liquefaction behavior, under three earthquake ground motions: Livermore, Chi-Chi, and Loma Prieta. Results showed that near-surface layers (0–2.3 m) experienced full liquefaction within two to three cycles, with excess pore pressure ratios (Ru) approaching 1.0 and peak pressures closely matching laboratory data with less than 10% deviation. The numerical approach revealed that traditional CPT-based cyclic resistance methods underestimated liquefaction susceptibility in intermediate layers due to limitations in accounting for pore pressure redistribution, evolving permeability, and seismic amplification effects. In contrast, the finite element model captured progressive strength degradation, revealing strength gain in deeper layers due to consolidation, while upper zones remained vulnerable due to low confinement and resonance effects. A critical threshold of Ru ≈ 0.8 was identified as the onset of rapid shear strength loss. The findings confirm the advantage of advanced numerical modeling over empirical methods in capturing the complex cyclic behavior of reclaimed sediments and support the adoption of performance-based seismic design for such geotechnically sensitive environments.

GeoHazards doi: 10.3390/geohazards7010007

Authors: Tulasi Ram Bhattarai Netra Prakash Bhandary Kalpana Pandit

The MJMA 7.6 (Mw 7.5) Noto Peninsula Earthquake of 1 January 2024 in Japan triggered widespread slope failures across northern Noto region, but their spatial controls and susceptibility patterns remain poorly quantified. Most previous studies have focused mainly on fault rupture, ground deformation, and tsunami impacts, leaving a clear gap in machine learning based assessment of earthquake-induced slope failures. This study integrates 2323 mapped landslides with eleven conditioning factors to develop the first data-driven susceptibility framework for the 2024 event. Spatial analysis shows that 75% of the landslides are smaller than 3220 m2 and nearly half occurred within about 23 km of the epicenter, reflecting concentrated ground shaking beyond the rupture zone. Terrain variables such as slope (mean 31.8°), southwest-facing aspects, and elevations of 100–300 m influenced the failure patterns, along with peak ground acceleration values of 0.8–1.1 g and proximity to roads and rivers. Six supervised machine learning models were trained, with Random Forest and Gradient Boosting achieving the highest accuracies (AUC = 0.95 and 0.94, respectively). Explainable AI using SHapley Additive exPlanations (SHAP) identified slope, epicentral distance, and peak ground acceleration as the dominant predictors. The resulting susceptibility maps align well with observed failures and provide an interpretable foundation for post-earthquake hazard assessment and regional risk reduction. Further work should integrate post-seismic rainfall, multi-temporal inventories, and InSAR deformation to support dynamic hazard assessment and improved early warning.

GeoHazards doi: 10.3390/geohazards7010006

Authors: Felipe de Jesús Escalona-Alcázar Estefanía García-Paniagua Luis Felipe Pineda-Martínez Baudelio Rodríguez-González Sayde María Teresa Reveles-Flores Santiago Valle-Rodríguez Cruz Daniel Mandujano-García

The formation of fractures in urban areas is typically related to construction processes, natural ground settlement, and material quality. In valleys, the distribution of ground fissures is associated with aquifer overexploitation and basement faulting. However, where the soil layer is only a few meters thick or absent, the influence of basement structures remains poorly understood. We hypothesize that urban fractures develop parallel to major basement faults. To test this, we applied a simple structural geology technique to systematically measure extension axes, from street fractures, throughout the town of Las Pilas. These axis orientations were then compared with those calculated for normal faults of Las Pilas Complex. Street fractures are generally about 1 cm thick, with lengths ranging from 0.51 to 1 m and occasionally reaching up to 3 m. They occur within streets 2 to 4 m wide, typically appearing as a single fracture within a 1–2 m wide fracture zone. Based on these characteristics, the fractures do not represent a significant hazard. Measurement results indicate that urban fractures primarily extend in an NE-SW direction. This is consistent with the orientation of the minimum principal stress axis (3) of the regional San Luis-Tepehuanes fault system, thereby supporting our hypothesis.

GeoHazards doi: 10.3390/geohazards7010004

Authors: Liliana Troncoso Francisco Javier Torrijo Echarri Luis Pilatasig Elías Ibadango Alex Mateus Olegario Alonso-Pandavenes Adans Bermeo Francisco Javier Robayo Louis Jost

Complex landslides have characteristics and parameters that are difficult to analyze. The landslide on 16 June 2024 in the rural community of Quilloturo (Tungurahua, Ecuador) caused severe damage (14 deaths, 24 injuries, and hundreds of affected families) related to the area’s geological, social, and anthropogenic conditions. Its location in the eastern foothills of Ecuador’s Cordillera Real exacerbated the effects of a landslide involving various processes (mud and debris flows, landslides, and rock falls). This event was preceded by intense rainfall lasting more than 10 h, which accumulated and caused natural damming of the streams prior to the event. The lithology of the investigated area includes deformed metamorphic and intrusive rocks overlain by superficial clayey colluvial deposits. The relationship between the geological structures found, such as fractures, joints, schistosity, and shear, favored the formation of blocks within the flow, making mass movement more complex. Geomorphologically, the area features a relief with steep slopes, where ancient landslides or material movements, composed of these colluvial deposits, have already occurred. At the foot of these steep slopes, on plains less than 300 m wide and bordered by the Pastaza River, there are human settlements with less than 60 years of emplacement and a complex history of territorial occupation, characterized by a lack of planning and organization. The memory of the inhabitants identified mass movements that have occurred since the mid-20th century, with the highest frequency of occurrence recorded in the last decade of the present century (2018, 2022, and 2024). Furthermore, it was possible to identify several factors within the knowledge of the inhabitants that can be considered premonitory of a mass movement, specifically a flood, and that must be incorporated as critical elements in decision-making, both individual and collective, for the evacuation of the area.

GeoHazards doi: 10.3390/geohazards7010005

Authors: Mahmood Ahmad Zia Ullah Sabahat Hussan Abdullah Alzlfawi Rohayu Che Omar Shay Haq Feezan Ahmad Muhammad Naveed Khalil

Effective mitigation of geotechnical risk and safety management of underground mine requires accurate estimation of rockburst damage potential. The inherent complexity of the rockburst phenomena due to nonlinear, high dimensional, and interdependent nature of the geological factors involved, however, makes predictive modeling a difficult task. The proposed research is based on the use of the K-Nearest Neighbor (KNN) algorithm to predict the risk of rockbursts with the use of microseismic monitoring data. Several key features like the ratio of total maximum principal stress to uniaxial compressive strength, energy capacity of support system, excavation span, geology factor, Richter magnitude of seismic event, distance between rockburst location and microseismic event, and rock density were applied as input parameters to extract critical rockburst precursor activities. In the test stage, the proposed KNN model recorded an accuracy of 75.50%, a precision of 0.913, a recall value of 0.509, and F1 Score of 0.576. The model is reliable with a significant performance indicating its efficacy in practice. The KNN model showed better classification results as compared to recently available models in literature and provided better generalization and interpretability. The model exhibited high prediction in classified low-risk incidents and had strong indicative capabilities towards high-risk situations, attributed to being a useful tool in rockburst hazard measurement.

GeoHazards doi: 10.3390/geohazards7010003

Authors: Yaohui Liu Xinkai Wang Jie Zhou Zhengguang Zhao

Co-seismic landslides are major secondary hazards in earthquakes, and their rapid detection is essential for emergency response, disaster assessment, and post-earthquake reconstruction. However, single classifiers often fail to meet practical detection requirements. This study proposes WPU, a weighted-voting-based multi-classifier method that assigns category-specific weights using the producer’s accuracy and user’s accuracy. A case study was conducted in Jiuzhaigou County, Sichuan Province, China, affected by the Ms 7.0 earthquake on 8 August 2017. A dataset of 193 co-seismic landslides was built through manual interpretation, and six commonly used remote-sensing-based detection methods were employed. The WPU method fused the outputs of all classifiers using PA- and UA-based weights. Results show that WPU achieved an overall accuracy of 0.9755 and a Kappa coefficient of 0.7848, demonstrating substantial improvement over individual classifiers while maintaining efficiency and timeliness. The proposed approach supports rapid emergency assessment and enhances the effectiveness of co-seismic landslide detection, providing a valuable reference for future post-earthquake hazard evaluations and enabling governments to respond more quickly to landslide disasters.

GeoHazards doi: 10.3390/geohazards7010002

Authors: Arnob Bormudoi Masahiko Nagai

Establishing quantitative causal relationships between drought indicators and vegetation degradation in the Chad Basin remained challenging due to statistical limitations of applying traditional Transfer Entropy to finite-length remote sensing time series. This study implemented a Machine Learning Enhanced Transfer Entropy structure to quantify directed information flow from primary drought drivers of precipitation and land surface temperature to vegetation dynamics from 2000 to 2023. A feed-forward neural network trained on 10,000 synthetic samples with known theoretical Transfer Entropies enabled causal inference from 24-year MODIS-derived NDVI, land surface temperature, and precipitation. The trained model was applied over 10 million pixels, producing Transfer Entropy maps. Results showed that precipitation and land surface temperature exerted comparable causal influences on NDVI, with mean Transfer Entropy values of 0.064 and 0.063, ranging from 0.041 to 0.388. Spatial analysis revealed distinct causal hotspots exceeding 75th percentile threshold of 0.069, indicating driver-specific vulnerability zones. The decline in mean annual NDVI from 0.225 in 2019 to 0.194 in 2023, together with spatially divergent hotspots, highlighted the need for geographically targeted land management. The study overcame finite-length time-series limitations and provided a replicable pathway for vulnerability assessment and climate adaptation planning in data-constrained drylands in the Chad Basin in Africa.

GeoHazards doi: 10.3390/geohazards7010001

Authors: Ma-Lyse Nema Bachir Mahaman Saley Arona Diedhiou Assiel Mugabe

Landslides are among the most significant disasters that threaten communities worldwide. This study sampled 384 respondents, using standardized interviews and field observations, to analyze how they perceived the factors influencing the incidence of landslides in the Kivu catchment of Rwanda, especially in landslide-prone areas. This study employs a mixed-methods approach that combines household surveys and interviews with key informants to assess how residents perceive landslide causes, warning signs, and impacts, which were analyzed statistically using SPSS. For further analysis, a binary logistic regression model and chi-square tests were used. The chi-square test findings highlighted that heavy rainfall, inappropriate agricultural practices, steep slopes, deforestation, road construction, earthquakes, and climate change were strongly correlated with landslide occurrence, with a p < 0.05 level of significance, while mining activities were not correlated with landslides. On the other hand, a binary logistic regression model revealed that, among the selected factors influencing landslide occurrence in the Kivu catchment, road construction (B = −0.644; p = 0.014), inappropriate agriculturalpractices (−1.177; p = 0.000), steep slopes (B = −0.648; p = 0.018), deforestation (B = −0.854; p = 0.007), and earthquakes (B = −1.59; p = 0.008) were negatively correlated, while heavy rainfall (B = 1.686; p = 0.000) and climate change (B = 1.784; p = 0.001) were positively correlated, and this was statistically significant for landslide occurrence at a p-value < 0.05. In contrast, mining activities (B = −0.065; p = 0.917) showed a negative coefficient that was statistically insignificant with respect to landslide occurrence in the study area. Future studies should integrate surveys with landslide hazard modeling tools for better spatial prediction of vulnerability and economic losses. Therefore, the findings from this study will contribute to sustainable natural disaster management planning in the western region of Rwanda.

GeoHazards doi: 10.3390/geohazards6040085

Authors: Tao Lin Hao Ding Wangyu Chen Yu Liu Hao Guo

Drought remains one of the most damaging natural hazards to agricultural production and is projected to continue posing substantial risks to food security in the future, particularly in major rice-growing regions. Based on the RCP4.5 and RCP8.5 scenarios under CMIP5, this study used a process-based crop growth model to simulate the growth of rice in China in different future periods (short-term (2031–2050), medium-term (2051–2070), and long-term (2071–2090)). We fitted rice vulnerability curves to evaluate the rice drought risk quantitatively according to the simulated water stress (WS) and yield. The results showed that the drought hazard in major rice-growing areas in China (MRAC) were low in the middle and high in the north and south. The areas without rice yield loss will decline in the future, while the areas with a high yield loss will increase, especially in southwestern China and the middle and lower Yangtze Plain (MLYP). Owing to the markedly increased evaporative demand and the reduced moisture transport caused by a weakening East Asian summer monsoon, northeastern China will be a high-risk area in the future, with the expected yield loss rates in scenarios RCP4.5 and RCP8.5 being 39.75% and 45.5%, respectively. In addition, under the RCP8.5 scenario, the yield loss rate of different return periods in south China will exceed 80%. A significant gap between rice supply and demand affected by drought is expected in the short-term future. The gaps will be 67,770 kt and 78,110 kt under the RCP4.5-SSP2 and RCP8.5-SSP3 scenarios, respectively. The methodology developed in this paper can support the quantitative assessment of drought loss risk in different scenarios using crop growth models. In the context of the future expansion of Chinese grain demand, this study can serve as a reference to improve the capacity for regional drought risk prevention and ensure regional food security.

GeoHazards doi: 10.3390/geohazards6040084

Authors: Ole Arve Misund Marius O. Jonassen Jan Otto Larsen

On 19 December 2015 and 21 February 2017, Longyearbyen was hit by major avalanches from the steep hillside of the mountain Sukkertoppen. In this article, we specifically consider the 2015 avalanche that destroyed eleven houses and buried nine people; seven were located and rescued, while two died. We describe the meteorological conditions leading up to the avalanche, the rescue operation, the media coverage, and the immediate aftermath of the catastrophe. Both events came as a result of warming, strong easterly winds, and drifting snow, with the December 2015 event being the most extreme. The 2017 avalanche damaged two houses, but no people were hurt. We analyse the catastrophes in relation to the knowledge of the risks and impacts of avalanches in Longyearbyen, as provided through field-based student courses at the University Centre of Svalbard (UNIS). To protect against further avalanche accidents, parts of Longyearbyen have been restructured, and physical barriers against avalanches have been installed on the hillside of Sukkertoppen. Now there are snow drift fences to reduce snow accumulation in the release areas, avalanche protection fences mounted in the hillside, and a large wall at the foot of the mountain to catch avalanche debris in the future. In hindsight, the accidents have contributed to an increased national awareness of the danger of severe weather events.

GeoHazards doi: 10.3390/geohazards6040083

Authors: Yi Zhou Ying Jing Yuesong Zheng Laizhong Ding Zhiyao Mai Yaxing Guo Dongya Wu Zhengxi Wang

Critical transmission lines frequently traverse geologically complex mountainous regions, where harsh environments and variable climatic conditions pose significant geohazard risks. Utilizing 163 Sentinel-1A scenes (January 2018 to October 2023), we employed Multi-Temporal InSAR (MT-InSAR) to derive the deformation field along the transmission corridor. Time-series analysis of the Lingshao (LS) line towers, interpreted through the principles of mining subsidence, revealed the mechanisms behind their differential tilt. Simultaneously, time-series deformation at the tower footings was input to a deep learning model for 365-day prediction; the accuracy and practical applicability of which were rigorously assessed. The results demonstrate that (1) a unidirectional subsidence funnel within the transmission corridor deformation field, in the absence of zonal settlement features, strongly indicates the presence of a goaf beneath the line; (2) the integrated approach combining time-series InSAR with the settlement trough method proves feasible for monitoring transmission tower tilt, as validated through field verification; (3) the magnitude and direction of tower tilt correlate directly with their position in the mining-induced subsidence basin, showing convergent tilt in tensile zones, divergent tilt in compressive zones, and uniform settlement in neutral zones; (4) for the eight selected typical tower footings, predicted deformation values ranged from −284.6 mm to −186.3 mm, showing excellent agreement with measurements through correlation coefficients of 0.989–0.999 and Root Mean Square Error (RMSE) values of 0.54–2.17 mm. The framework enables proactive hazard avoidance during line routing and provides early warning for tower defects, significantly enhancing power infrastructure resilience in mining-affected regions.

GeoHazards doi: 10.3390/geohazards6040082

Authors: Tomokazu Konishi

Modern statistical techniques enable quantitative characterisation of seismic activity. Analysis of the 2011 Tohoku megathrust earthquake revealed clear precursory signals: shortened inter-event intervals, increased magnitude scale (σ), and a pronounced precursory swarm immediately before the mainshock. While unique to this magnitude 9 event, here I present subtler anomalies that may precede magnitude 7-class events, particularly when swarms occur. In such cases, magnitude distributions often differ from background seismicity, frequently showing elevated location (μ) and scale (σ). Conversely, σ is sometimes reduced, particularly in volcanic regions, where large earthquakes may occur without discernible swarms. Detection of swarm activity and analysis of magnitude parameters thus remain central to seismic risk assessment. If swarm characteristics resemble background levels, the likelihood of a major event is presumably low. However, the distinct, immediate precursory swarm observed before the Tohoku earthquake has not been replicated elsewhere. These findings indicate that statistical anomalies may signal elevated risk but are unlikely to enable precise temporal prediction of seismic events.

GeoHazards doi: 10.3390/geohazards6040081

Authors: Alexandra Moshou

During January–February 2025, the Santorini volcanic complex experienced intense seismic activity, increasing interest and concern regarding the possible reactivation of the magmatic system. This study investigates the spatial and magnitude distribution of seismic events with the aim of distinguishing between tectonic and volcanic earthquakes and understanding the underlying processes governing seismicity in the region. The analysis is based on data from the national and local seismic network, including epicenter and focus determination, local magnitude (ML) calculation, depth analysis, statistical processing, and the application of machine learning methods for event classification. The results show that tectonic earthquakes are mainly located at depths, D > 8 km along active faults, while volcanic earthquakes are concentrated at shallower levels (D < 5 km) below the volcanic center. The analysis of b values suggests the differentiation of the focal mechanism, with higher values for volcanic events, which is related to fluid and magmatic pressure processes. The spatiotemporal evolution of seismicity demonstrates seismic swarm characteristics, without a main earthquake, which are attributed to processes within the subvolcanic system. The study contributes to improving the understanding of the current seismovolcanic crisis of Santorini and enhances the ability to identify magmatic instability processes in a timely manner, critical for hazard assessment and monitoring of the South Aegean volcanic arc.

GeoHazards doi: 10.3390/geohazards6040080

Authors: Daniel Jose L. Buhay Bianca Dorothy B. Brusas John Karl A. Marquez Paulo P. Dajao Robelyn Z. Mangahas-Flores Nicole Jean L. Mercado Oliver Paul C. Halasan Hazel Andrea L. Vidal Carlos Jose Francis C. Manlapat

The 17 November 2023 MW 6.8 earthquake located offshore of Southern Mindanao, Philippines, triggered soil liquefaction along the lowlands of the Sarangani Peninsula. Detailed mapping, geomorphological interpretations, geophysical surveys, comparison with predictive models, and grain size analysis were conducted to obtain a comprehensive understanding of the earthquake parameters and subsurface conditions that permitted liquefaction. Soil liquefaction manifested as sediment and water vents, fissures, lateral spreads, and ground deformation, mainly along landforms with shallow groundwater levels such as river deltas, fills, floodplains, and beaches. In populated areas, ground failure due to liquefaction also damaged some buildings. All these impacts fall within the boundaries of the available liquefaction hazard maps for Sarangani Peninsula and the predictive empirical equations generated by various authors. Simulated peak ground acceleration values also indicate that sufficient ground shaking was generated for the soil to liquefy. Refraction microtremor (ReMi) surveys reveal shear wave velocities ranging from 121 to 215 m/s, which infer the presence of soft and stiff soils beneath the surface, promoting the sites’ potential to liquefy. Grain size analyses of sediment ejecta confirm the presence of these liquefiable sediments from the subsurface, with grain sizes ranging from silt to medium sand. The results of three-component microtremor (3CMt) surveys also show varying sediment thicknesses, which are consistent with the thickness of soft sediment layers inferred by ReMi surveys. The information resulting from this study may be useful for researchers, planners, and engineers for liquefaction hazard assessment and mitigation, especially in the Sarangani Peninsula.

GeoHazards doi: 10.3390/geohazards6040079

Authors: Stuti Chaudhary Arvind Chandra Pandey Chandra Shekhar Dwivedi Bikash Ranjan Parida Navneet Kumar

This present study demonstrates the assessment of agricultural drought hazard based on satellite indices for drought risk mapping in part of the South Koel river basin (India) with coverage of (7261 km2). Satellite-based drought indices and NDVI anomalies have been calculated using Moderate Resolution Imaging Spectroradiometer (MODIS) data sets. The variations in vegetation condition from years 2000–2023 for the month of October were examined using additional NDVI and LST products from MODIS data. Vegetation Condition Index (VCI), Temperature Condition Index (TCI), and Vegetation Health Index (VHI) are satellite-based drought indices that were used for agricultural mapping. The study area’s long-term NDVI anomaly demonstrates the negative impact of climate extremes during the past 23 years. Values in drought-prone areas ranged from 10 to 50. The majority of the study area has been severely impacted by drought in 2001, 2005, 2010, and 2023, with water scarcity and mediocre vegetative conditions. Results showed that 59.33% of the study area is in drought risk zone and, among the five districts in the study area, Gumla is in high-risk zone. It covers 610 villages and spans an area of 3275 km2, out of which 2119 km2 with a population of 415,341 are specifically at high risk.

GeoHazards doi: 10.3390/geohazards6040078

Authors: Somasundharam Magalingam Selvakumar Radhakrishnan

The Late Holocene flood history of the Cauvery River floodplain in the Poompuhar region was reconstructed using a multiproxy sedimentological approach applied to three trench cores. Lithostratigraphy, loss on ignition (LOI), magnetic susceptibility (MS), sand–silt–clay textural analysis, granulometric statistics (Folk and Ward), Passega CM diagrams, and grain angularity provide complementary evidence to differentiate high-energy flood deposits from background slackwater sediments. Grain-size processing and statistical analyses were carried out in R using the G2Sd package, ensuring reproducible quantification of mean size, sorting, skewness, kurtosis, and transport signatures. We identified 10 discrete high-energy event beds. These layers are characterised by >80% sand content, low LOI (<3.5%), and low frequency-dependent MS (χfd% < 2%), confirming rapid, mineral-dominated deposition. A tentative chronology, projected from the regional aggradation rate, suggests two major flood clusters: a maximum-magnitude event at ~3.2 ka and a synchronous cluster at ~1.6–1.8 ka. These events chronologically align with the documented phases of channel avulsion in the adjacent Palar River Basin, supporting the existence of a synchronised Late Holocene climato-tectonic regime across coastal Tamil Nadu. This hydrological evidence supports the hypothesis that recurrent high-magnitude flooding triggered catastrophic channel avulsion of the Cauvery distributary, leading to the fluvial abandonment and decline of the ancient port city of Poompuhar. Securing an absolute chronology requires advanced K-feldspar post-IR IRSL dating to overcome quartz saturation issues in fluvial deposits.

GeoHazards doi: 10.3390/geohazards6040077

Authors: Antonio Oliva Jorge Olcina

This article proposes a novel methodology based on the 2D hydraulic model of the HEC-RAS software, with a stepped ascending hydrograph that allows determining the maximum capacities of the channel (value at which overflow occurs), identifying potential breaking and overflow points, and the affected areas. This methodology also allows for determining whether the theoretical hydraulic capacities indicated by official agencies correspond to the current capacity of the channel. The areas analyzed correspond to the urban channel sections of the Segura River as it passes through Murcia, Orihuela, Almoradí, and Rojales. The results show that the capacity is much lower than the estimated flows, which explains the overflows of the Segura River in some sections. These results have been compared with the events of the September 2019 flood. The discussion addresses some potential problems identified during the modeling process and how they were resolved. The importance of understanding these capacities for better flood management is also highlighted. It is concluded that the Segura River channel capacity is lower, that it is a method that can be extrapolated to other rivers, and that it allows for more effective management of river floods, reducing the impacts on the population.

GeoHazards doi: 10.3390/geohazards6040076

Authors: Gerassimos A. Papadopoulos

The Santorini volcano in the South Aegean Volcanic Arc is of great scientific importance. Knowledge of historical eruptions is valuable for better understanding the volcanic cycle and for improved hazard assessments. One of the little-known historical eruptions occurred either in 1570 or in 1573 or from 1570 to 1573 CE. We bring to light a very little-known but reliable Greek manuscript dated in 1588 CE which improves our knowledge about this eruption. The manuscript documents that the eruption occurred in 1572 and took place within the sea caldera between Santorini and Palaia Kameni. It makes it clear that “fire, smoke, and stones” were coming out between the two islands and a new volcanic island named Mikri Kameni was born. This landscape has been verified by independent maps of the 17th and 18th centuries. The floating pumice was transported by the sea as far as to Thessaloniki and Constantinople. Also, we learn a lot about the consequences of the eruption: (1) smoke and heat destroyed the vineyards and the planting season on Santorini, i.e., spring–summer, (2) it is likely that sulfurous gases were released, and (3) the residents of Santorini were forced to move to nearby islands. The duration of the eruption was ~1 year, but the fire and smoke disappeared suddenly. The Volcanic Explosivity Index of the eruption was estimated to be as high as 3.

GeoHazards doi: 10.3390/geohazards6040075

Authors: Alaa Kourdey Omar Hamza Hamzah M. B. Al-Hashemi

Over the past five decades, the Tallet Alsauda district of Aleppo (Syria) has experienced multiple catastrophic collapses, attributed to a network of subsurface chalk cavities formed through historic quarrying and possible natural karstification. Yet, no comprehensive investigation has previously been conducted to characterise the cavities or clarify the governing failure mechanisms. Such assessments are particularly difficult in historic urban environments, where void geometries are irregular, subsurface data scarce, and underground access limited. This study addresses these challenges through an integrated programme of fourteen boreholes, laboratory testing, and inverse-distance interpolation to reconstruct subsurface geometry and overburden thickness. These data-informed three-dimensional finite element simulations are designed to test the hypothesis that chalk deterioration, driven by both natural and anthropogenic processes, controls the instability of cavity roofs. Rock mass parameters, particularly the Geological Strength Index (GSI), were progressively reduced and evaluated against the site’s documented collapse history. The simulations revealed that a modest decline in GSI from ~53 to 47 precipitated abrupt displacements (>300 mm) and upward-propagating plastic zones, consistent with field evidence of past collapses. These results confirm that instability is governed by threshold reductions in material strength, with sewer leakage identified as a principal trigger accelerating chalk softening and roof destabilisation.

GeoHazards doi: 10.3390/geohazards6040074

Authors: Xianghe Ji Klaus Reicherter

The Longshou Shan area is located on the northeastern margin of the Tibetan Plateau in northwest China. The study area is located where the sinistral Altyn Tagh and Haiyuan Faults overlap and the Qilian Shan thrust fault systems in the northeastern Kunlun–Qaidam Block converge. This region experiences frequent seismic events, including large-magnitude earthquakes, which are significant indicators of ongoing tectonic deformation and stress accumulation in the Earth’s crust. The seismicity of Longshou Shan is not only a consequence of its tectonic setting but also a key factor in understanding the seismic hazard posed to the surrounding areas. The tectonic activity within the Longshou Shan region of NW China is a focus of our geomorphological research due to its significance in understanding the complex interactions between tectonic forces and surface processes. Situated on the northeastern edge of the Tibetan Plateau and along the eastward trace of the Altyn Tagh Fault, Longshou Shan is crucial for investigating the plateau’s northward expansion. This study leverages ALOS-based digital elevation models (DEMs) and geomorphic indices to evaluate the tectonic activity in the area, employing various indices such as mountain front sinuosity, valley floor width-to-height ratio, hypsometric curves, asymmetry factors, basin shape indices, and channel steepness index to provide a comprehensive tectonomorphological analysis. Our results indicate intense tectonic activity on both sides of Longshou Shan, making it a highly hazardous seismic area. We also highlight the importance of thrust faults and related crustal shortening in the formation and expansion of the plateau.

GeoHazards doi: 10.3390/geohazards6040072

Authors: Emmanuel Chapron Thierry Courp Pieter van Beek Kazuyo Tachikawa Guillaume Jouve Léo Chassiot Didier Jézéquel Patrick Lajeunesse Thomas Zambardi Edouard Bard

This study combines a multidisciplinary approach to Pyrenean and Alpine glacial lakes to characterize the sensitivity of Late Glacial to Holocene subaquatic flood deposits in deltaic environments to slope failures triggered either by earthquakes, rockfalls, or snow avalanches. To clarify the possible interactions between environmental changes and these natural hazards in mountain and piedmont lakes, we analyze the lacustrine sedimentary records of key historical events and discuss the recurrence of similar regional events in the past. High-resolution seismic profiles and sediment cores from large perialpine lakes (Bourget, Geneva, and Constance) and from small mountain lakes in the French Alps and the Pyrenees were used to establish a conceptual model linking environmental changes, tributary flood sedimentary processes, subaquatic deltaic depocenters, and potentially tsunamigenic mass-wasting deposits. These findings illustrate the specific signatures of the largest French earthquakes in 1660 CE (northern Pyrenees) and in 1822 CE (western Alps) and suggest their recurrence during the Holocene. In addition, the regional record in the Aiguilles Rouges massif near Mont Blanc of the tsunamigenic 1584 CE Aigle earthquake in Lake Geneva may be used to better document a similar Celtic event ca. 2300 Cal BP at the border between Switzerland and France.

GeoHazards doi: 10.3390/geohazards6040073

Authors: David Bakhsoliani Archil Magalashvili George Gaprindashvili

Identifying landslide boundaries and morphological features using traditional methods is labor-intensive, costly, and often limited—especially in areas altered by human activity or covered with dense vegetation. In such cases, modern remote sensing methods are considered a good alternative; however, their accuracy and reliability also depend on several factors. This study aims to identify landslide boundaries and morphological features using modern remote sensing techniques and to compare and validate the derived parameters with those obtained through traditional field methods. In this study, the remote sensing technology employed is a high-resolution digital elevation model (HRDEM) generated by a LiDAR sensor mounted on an unmanned aerial vehicle (UAV). Based on this dataset, various terrain parameters were analyzed, including slope, aspect, contour, curvature, hillshade, the topographic ruggedness index (TRI), the topographic position index (TPI), and the topographic wetness index (TWI). Individual analysis, composite analysis, and principal component analysis (PCA) of these parameters enabled the identification of the landslide boundaries and key morphological elements. This study was conducted on a landslide-prone slope in the Surami area of Georgia, which is characterized by extensive anthropogenic impact. The accuracy of the LiDAR-derived results was confirmed through field validation. This study demonstrates the effectiveness of UAV-LiDAR technology in areas affected by anthropogenic activity.

GeoHazards doi: 10.3390/geohazards6040071

Authors: Sagar Kumar Swain Bikash Ranjan Parida Ananya Mallick Chandra Shekhar Dwivedi Manish Kumar Arvind Chandra Pandey Navneet Kumar

The lower Mahanadi basin in eastern India is experiencing significant land and soil transformations that directly influence agricultural sustainability and ecosystem resilience. In this study, we used geospatial techniques to analyze the spatial-temporal variability of soil quality and land cover between 2011 and 2020 in the lower Mahanadi basin. The results revealed that the cropland decreased from 39,493.2 to 37,495.9 km2, while forest cover increased from 12,401.2 to 13,822.2 km2, enhancing soil organic carbon (>290 g/kg) and improving fertility. Grassland recovered from 4826.3 to 5432.1 km2, wastelands declined from 133.3 to 93.2 km2, and water bodies expanded from 184.3 to 191.4 km2, reflecting positive land–soil interactions. Soil quality was evaluated using the Simple Additive Soil Quality Index (SQI), with core indicators bulk density, organic carbon, and nitrogen, selected to represent physical, chemical, and biological components of soil. These indicators were chosen as they represent the essential physical, chemical, and biological components influencing soil functionality and fertility. The SQI revealed spatial variability in texture, organic carbon, nitrogen, and bulk density at different depths. SQI values indicated high soil quality (SQI > 0.65) in northern and northwestern zones, supported by neutral to slightly alkaline pH (6.2–7.4), nitrogen exceeding 5.29 g/kg, and higher organic carbon stocks (>48.8 t/ha). In contrast, central and southwestern regions recorded low SQI (0.15–0.35) due to compaction (bulk density up to 1.79 g/cm3) and fertility loss. Clay-rich soils (>490 g/kg) enhanced nutrient retention, whereas sandy soils (>320 g/kg) in the south increased leaching risks. Integration of LULC with soil quality confirms forest expansion as a driver of resilience, while agricultural intensification contributed to localized degradation. These findings emphasize the need for depth-specific soil management and integrated land-use planning to ensure food security and ecological sustainability.

GeoHazards doi: 10.3390/geohazards6040070

Authors: Johanna Schiffmann Thomas R. Walter Linda Sobolewski Thilo Heinken

Since March 2021, a series of volcanic eruptions on Iceland’s Reykjanes Peninsula has repeatedly triggered wildfires in moss-dominated heathlands—an unprecedented phenomenon in this environment. These fires have consumed extensive organic material, posing emerging health risks and long-term ecological impacts. Using high-resolution multispectral satellite data from the Copernicus program, we present the first quantitative assessment of the spatial and temporal dynamics of volcanic wildfire activity. Our analysis reveals a cumulative burned area extending 11.4 km2 beyond the lava flows, primarily across low-relief terrain. Time series of the Normalized Difference Vegetation Index (NDVI) capture both localized fire scars and diffuse, landscape-scale burn patterns, followed by slow and spatially heterogeneous recovery. Complementary ground surveys conducted in August 2024 document diverse post-fire successional pathways, with vegetation regrowth and species composition strongly governed by microtopography and substrate texture. Together, these results demonstrate that volcanic wildfires represent a novel and consequential secondary disturbance in Icelandic volcanic systems, highlighting the complex and protracted recovery dynamics of moss heath ecosystems following fire-induced perturbation.

GeoHazards doi: 10.3390/geohazards6040069

Authors: Asma Gharnate Hatim Sanad Majda Oueld Lhaj Nadia Mhammdi

Coastal boulder deposits (CBDs) are among the most striking geomorphic signatures of extreme wave activity, recording the action of both tsunamis and severe storms. Their significance extends beyond geomorphology, providing geological archives that capture rare but high-impact events beyond the scope of instrumental or historical records. This review critically examines the origins, emplacement mechanisms, diagnostic morphology, monitoring tools, and global case studies of CBDs with the aim of clarifying the storm–tsunami debate and advancing their application in coastal hazard assessment. A systematic literature survey of 77 peer-reviewed studies published between 1991 and 2025 was conducted using Scopus and Web of Science, with inclusion criteria ensuring relevance to extreme-wave processes, geomorphic analysis, and chronological methods. Multiproxy approaches were emphasized, integrating geomatics (RTK-GPS, UAV-SfM, TLS, LiDAR), geochronology (14C, U–Th, OSL, cosmogenic nuclides, VRM), and hydrodynamic modeling. Findings show that tsunamis explain the largest and most inland megaclasts, while modern storms have proven capable of mobilizing boulders exceeding 200 t at elevations up to 30 m. Many deposits are polygenetic, shaped by successive high-energy events, complicating binary classification. CBDs emerge as multifaceted archives of extreme marine forcing, essential for refining hazard assessments in a changing climate.