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.

The Armenian Highlands, a tectonically active segment of the Arabia‐Eurasia collision zone, exhibit widespread Quaternary volcanism, rapid uplift, and intense seismicity. However, the lithospheric processes driving these phenomena remain poorly understood. We present the first P‐ and S‐wave body‐wave tomography model of Armenia's crust and uppermost mantle, derived from regional earthquakes recorded by both permanent and temporary seismic networks. Our model reveals that beneath the Armenian Highlands, the crust is underlain by a pronounced low‐velocity anomaly in the uppermost mantle (∼40 km depth), indicative of asthenospheric upwelling and melt generation. This anomaly spatially correlates with monogenetic volcanic fields (e.g., Gegham and Syunik), supporting magma ascent through thermally weakened conduits. The lithosphere adheres to a “crème brûlée” rheological model, characterized by a seismogenic brittle layer (10–25 km depth, marked by high‐velocity anomalies) atop a ductile lower crust and uppermost mantle (with negative Vp and Vs anomalies). Beneath the Gegham Plateau, a thinner brittle high‐velocity layer coincides with elevated seismicity at 10–20 km depth, suggesting magmatically induced earthquakes rather than purely tectonic strain release. Collectively, this work establishes a framework for understanding collision‐related magmatism in comparable orogens.

The May 2024 Lernapat landslide in northern Armenia occurred following rainfall and coincided with leakage from an irrigation pipeline. Its subsurface structure was investigated using UAV terrain analysis, four boreholes, laboratory testing, electrical resistivity tomography (ERT), multichannel analysis of surface waves (MASW), microtremor H/V (horizontal-to-vertical spectral ratio) measurements, ground-penetrating radar (GPR), and limit-equilibrium modelling. Boreholes identified mechanically weakened intervals at depths of 16.4–16.7 m and 18.4–20.0 m. The borehole observations were considered together with the ERT and MASW results to constrain the probable basal deformation zone and the adopted slip-surface geometry. H/V measurements provided supplementary spectral information; their depth estimates were treated as approximate equivalent thicknesses rather than independent confirmation of the MASW interpretation. The existing slope yielded factors of safety of 0.980 under static loading and 0.496 under pseudo-static loading at Kh = 0.16. A modelled groundwater lowering of 7.0 m increased these values to 1.214 and 0.616, respectively. Within the staged embankment-construction sequence, the calculated static factors of safety ranged from 1.372 to 1.499, whereas the corresponding pseudo-static values ranged from 0.657 to 0.689. None of the investigated stabilization scenarios reached Fs = 1.00 under pseudo-static loading at Kh = 0.16. No separate calculations were performed at Kh = 0.20. These factors of safety are conditional on the adopted model; the effects of alternative basal geometries and shear-strength parameters were not quantified. The results illustrate how the integration of geological, hydrogeological, electrical, and seismic observations can provide a field-constrained basis for evaluating groundwater sensitivity and stabilization scenarios.

The Pambak-Sevan-Syunik Fault (PSSF) is one of the major active right-lateral strike-slip structures of the Lesser Caucasus, accommodating deformation along the northern margin of the Arabian-Eurasian collision zone. In its northern segments, overlapping fault strands form pull-apart basins that localize deformation and increase seismic hazard. One of the most prominent of these structures is the Vanadzor depression, a densely populated urban basin developed at the junction of the Arpi-Vanadzor and Vanadzor-Artanish fault segments. In this study, we integrate paleoseismological, archaeoseismological, and new seismological data to reassess the tectonic behavior and seismic potential of the northern PSSF.A paleo-event with a magnitude of Mw ≥ 7.2 and an epicenter within the Vanadzor depression indicates the high seismic potential of the region. Furthermore, evidence of past large earthquakes, combined with the absence of significant instrumental or historically recorded events, suggests long recurrence intervals.New seismological constraints are provided by the March 8, 2025 Mw 4.8 earthquake and its aftershock sequence, which illuminate the present-day kinematics of the fault system. Focal mechanism solutions reveal an oblique reverse faulting for the main shock within a transpressional stress regime, while aftershocks exhibit local transtensional deformation, reflecting complex fault-segment interactions within the pull-apart basin. Strong-motion data show anomalously high peak ground acceleration at relatively distant stations, which may reflect the combined effect of local site conditions and fault-controlled wave propagation.The combined dataset indicates that the Vanadzor depression remains a tectonically active structure capable of hosting large earthquakes, and that fault geometry can significantly influence the pattern of local ground-motion. These findings underscore the importance of incorporating detailed fault geometry and segmentation into tectonic and seismic hazard assessments in intracontinental strike-slip systems.

We perform Rayleigh wave ambient noise tomography to investigate crustal seismic velocity structure and sources of volcanism in Armenia. Armenia, a key part of the tectonically and volcanically active Caucasus‐Anatolia region, is actively being deformed by the ongoing Arabian‐Eurasian continental collision. Unlike typical intracontinental settings, Armenia exhibits exceptional diversity of volcanic compositions and eruption styles: large stratovolcanoes are interspersed among more broadly distributed monogenetic cones and extensive lava flows. This study presents the first seismic tomography model of Armenia with sufficient resolution to infer potential magma sources. We analyze ∼19 months of continuous ambient noise data recorded by 32 seismic stations, extracting Green's functions and Rayleigh wave dispersion curves. A two‐step tomographic inversion first yields 2D group velocity maps, followed by a 3D shear‐wave velocity model. Synthetic tests confirm the model's resolution and ability to detect lateral and vertical velocity anomalies. Our results reveal prominent low‐velocity anomalies down to 25 km beneath monogenetic cones, likely indicating magma transport zones. At greater depths, velocity anomalies reverse sign. A high‐velocity zone at 40 km depth beneath dispersed cones suggests crustal thinning and asthenosphere upwelling. Beneath Lake Sevan, we identify two distinct structures: a low‐velocity anomaly in the NW linked to fault‐related fracturing and fluid saturation, and a high‐velocity anomaly in the SE that may represent a rigid block, possibly remnant oceanic crust. This study provides new insights into crustal structure beneath Armenia, shedding light on its magmatic and tectonic evolution.

Armenia is located within the Arabia–Eurasia collision zone and is exposed to a significant seismic hazard associated with active fault systems capable of generating destructive earthquakes. The 1988 Spitak earthquake highlighted the vulnerability of Armenian urban areas and the need for reliable seismic risk assessment methods. This study presents the first harmonized scenario-based seismic risk assessment framework for six major Armenian cities by integrating seismotectonic source characterization, deterministic ground-motion modeling, locally derived Vs30-based site characterization, GIS-based exposure modeling, and vulnerability assessment within the ELER (Earthquake Loss Estimation Routine) platform. Vulnerability functions were adapted to Armenian building typologies and calibrated using observed damage from the 1988 Spitak earthquake. Deterministic earthquake scenarios (Mw 6.5–7.3) were developed based on the seismic potential of the country’s principal active fault systems. The results reveal substantial spatial variability in seismic risk controlled by differences in ground-motion intensity, local site conditions, building vulnerability, and population exposure. Masonry-dominated urban areas exhibit the highest relative structural losses, whereas Yerevan experiences the greatest absolute losses because of its large population and concentrated building stock. Severe damage and collapse (D4–D5) may affect more than 20–25% of buildings in the most vulnerable cities. Validation against observed 1988 earthquake damage demonstrates the applicability of the proposed framework for seismic risk reduction, emergency preparedness, and long-term urban resilience planning in Armenia.