We invite abstracts on works to image rupture kinematics and simulate earthquake dynamics using numerical method to improve understanding of the physics of earthquakes. In particular, these are works that aim to develop a deeper understanding of earthquake source physics by linking novel laboratory experiments to earthquake dynamics, and studies on earthquake scaling properties. For instance assessing the roles fluids and heterogeneities play in influencing, directing, or obstructing the behavior of slow earthquakes and how they impact rupture mechanics. Other works show progress in imaging earthquake sources using seismic data and surface deformation measurements (e.g. GNSS and InSAR) to estimate rupture properties on faults and fault systems. Especially for slow earthquakes we look for technological innovations, showcasing cutting-edge tools and methodologies that boost our proficiency in detecting, analyzing, and understanding slow earthquakes.
We want to highlight strengths and limitations of each data set and method in the context of the source-inversion problem, accounting for uncertainties and robustness of the source models and imaging or simulation methods. Contributions are welcome that make use of modern computing paradigms and infrastructure to tackle large-scale forward simulation of earthquake process, but also inverse modeling to retrieve the rupture process with proper uncertainty quantification. We also welcome seismic studies using data from natural faults, lab results and numerical approaches to understand earthquake physics.
How large earthquakes initiate, propagate, and ultimately arrest remains a central question in seismology, particularly in high-risk regions such as the Istanbul metropolitan area, home to more than 20 million people. The 2025 Mw 6.2 Central Marmara earthquake ruptured a ~20 km-long segment of the right-lateral east-west trending North Anatolian Fault Zone beneath the Sea of Marmara (hereafter NAFZ-Marmara), immediately adjacent to a long-recognized Istanbul seismic gap. The ruptured fault segment belongs to a complex, structurally heterogeneous system, bounded by a creeping segment to the west and a locked segment to the east. This setting allows us to investigate how slip heterogeneity may control rupture behavior.
Here, we combine newly derived seismicity and focal mechanism catalogs spanning both the pre- and post-mainshock periods with strong-motion back-projection imaging to constrain earthquake nucleation processes and to characterize rupture propagation, aftershock evolution, and triggered seismicity. We observe that roughly two weeks before the mainshock, seismicity subtly localized and migrated ~10 km toward the future epicentral area from the west, within a portion of the NAFZ-Marmara characterized by high creeping rates and the presence of repeating earthquakes. Back-projection reveals that the mainshock rupture propagated unilaterally ~24 km eastward through a sedimentary basin at velocities approaching the shear-wave speed, but without evidence of supershear behavior, before abruptly arresting upon reaching a topographic high. Notably, immediately ahead of the eastern rupture tip, aftershock activity is very sparse. In contrast, no evidence is found for rupture propagation toward the west, suggesting that the creeping segment inhibited rupture growth in that direction. This is further supported by the aftershock migration pattern to the west, which evolves approximately logarithmically with time, consistent with afterslip-driven aftershocks.
Despite the abrupt rupture arrest at the eastern rupture tip, the earthquake triggered intense seismicity in a region located ~15–20 km south of Istanbul, spatially disconnected from the actual rupture, but kinematically linked to the NAFZ-Marmara system. The timing and source kinematics of the triggered events, occurring within minutes to days and persisting for months after the mainshock, indicate a strong response of the surrounding fault network to the stress perturbations imposed by the rupture.
Our results show that the 2025 Mw 6.2 Central Marmara earthquake ruptured a complex fault system in which frictional and structural heterogeneities strongly modulated rupture nucleation, propagation, arrest, and the spatiotemporal pattern of aftershocks and triggered seismicity. Finally, we highlight that the abrupt eastern rupture termination and the activation of faults immediately south of the Istanbul megacity are particularly significant in the context of the region’s seismic hazard assessment.
How to cite: Núñez-Jara, S., Vera, F., Scotto di Uccio, F., Fabisch, O., Dresen, G., Bohnhoff, M., and Martínez-Garzón, P.: Structural and frictional controls on the nucleation, propagation, and arrest of the 2025 Mw 6.2 Central Marmara Earthquake, Türkiye, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12759, https://doi.org/10.5194/egusphere-egu26-12759, 2026.
Moderate earthquakes can be as destructive as large megathrust events, particularly when they occur close to metropolitan areas. On September 8, 2023, a moderate Mw 6.8 earthquake struck central Morocco, causing approximately 3,000 fatalities, mainly in the Marrakech region. The earthquake occurred in the High Atlas Mountains, an area characterized by relatively low seismic activity, where the largest previously reported events did not exceed Mb ≈ 5.5. Several questions remain open regarding the physics of this earthquake. The focal mechanism solutions indicate two possible fault geometries: one high-dip plane and one low-dip plane. Some studies suggesting a rupture on a low-dip plane, considering that the continental crust may not be able to host earthquakes at greater depths, while other studies propose that mantle upwelling could have trigger a rupture on a high-dip fault plane.
In this study, we investigate the possible physical processes underlying the 2023 Al Haouz earthquake using a high-resolution seismic catalog and a joint Bayesian kinematic inversion of the rupture history. The seismic catalog spans one year, from January to December 2023, , and was constructed using the PhaseNet framework together with a 1D velocity model. We perform a joint Bayesian kinematic inversion that incorporates previously published geodetic observations (InSAR) with the limited available near-field and regional seismic data, in order to constrain the rupture propagation.
Our earthquake catalog allows us to image seismicity aligned with the high-dip fault plane, providing additional constraints to distinguish between the two proposed fault geometries. In addition, we do not observe clear evidence of sustained seismic activity at greater depths either prior to or following the mainshock. This observation does not strongly support a hypothetical active upward migration of seismicity from depth, as might be expected in the presence of mantle upwelling. The joint inversion indicates a relatively simple rupture process, dominated by a single major slip patch that released most of the seismic energy before propagating away from the hypocenter. Our results suggest that tectonic loading mechanisms, alternative to mantle upwelling, could have acted as the primary source of stress accumulation in the region.
How to cite: Sanchez-Reyes, H., Caballero, E., Chlieh, M., and Jabour, N.: Analysis of the 2023 Mw6.8 Al-Haouz, Morroco, Earthquake using a Bayesian Inversion and an extensive seismic catalog., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14544, https://doi.org/10.5194/egusphere-egu26-14544, 2026.
The 2025 Mw 7.8 Myanmar earthquake produced one of the longest continental strike-slip ruptures ever recorded. Expanding beyond a known seismic gap, it struck a densely populated region with vulnerable infrastructure. Study of this earthquake is hampered by limited seismic data coverage, yet uniquely informed by exceptional CCTV footage, a near-fault station, and comprehensive satellite geodetic imagery.
To understand the earthquake’s dynamics, we explore hundreds of 3‑D dynamic rupture simulations, all informed by a static slip model on a helix‑shaped fault geometry, which we geodetically inferred from Sentinel-1A/2 and ALOS-2 satellite data. Exploring various fault friction‑initial stress combinations, we identify a family of models characterized by near-critical prestress, low strength drop, and short slip‑weakening distances proportional to slip. These unexpected dynamic parameters are required to reconcile the inferred fast rupture speed with the low crustal wave velocities and the low inferred stress drop of the event. These preferred dynamic rupture models can explain space‑geodetic fault offsets, CCTV‑derived on‑fault slip‑rates, teleseismic waveforms and back-projection, and a near‑fault strong‑motion record. They spontaneously initiate unilateral supershear rupture shortly after nucleation, predominantly propagating at supershear speeds southward within a deep band. In contrast, shallow rupture, although driven by the underlying faster supershear rupture, remains sub‑shear, causing strong curvature of the rupture front. This depth‑dependent rupture speed reconciles the fast average rupture speed imaged by teleseismic back‑projection and confirmed by the early S‑wave onset at station NPW, and the subshear pulse-like phase captured by CCTV.
Our dynamic rupture models imply low fracture energy, characteristic of a structurally mature, clay‑rich fault zone, potentially facilitated by hydrothermal alteration and elevated pore-fluid pressure. Additional rupture models incorporating bimaterial effects show that while a bimaterial contrast may explain the subshear–supershear dichotomy between northward- and southward-propagating rupture, such a contrast is inconsistent with the NPW record, suggesting that bimaterial conditions were likely localized. Our results demonstrate that dynamic rupture ensembles informed from a static slip model and validated by interdisciplinary observations can offer a physically grounded route for earthquake characterization, complementary to kinematic modeling. Our results indicate that the Myanmar earthquake was critically influenced by spatial variations in frictional properties and fault stress across low-fracture-energy faults with important implications for assessing seismic hazard of major strike-slip faults.
How to cite: Ulrich, T., Zou, X., Marchandon, M., Schliwa, N., Tan, F., Gabriel, A.-A., Fan, W., Shearer, P., Thant, M., Tin, T. Z. H., Lindsey, E. O., and Fialko, Y.: Could the complex rupture dynamics of the 2025 Mw 7.8 Myanmar Earthquake have been predicted? , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14302, https://doi.org/10.5194/egusphere-egu26-14302, 2026.
Global observations reveal faults respond to earthquake ruptures through localized on-fault slip and distributed off-fault deformation (OFD). Deformation becomes increasingly delocalized along faults that are immature or geometrically complex, rupture slowly, or propagate through sediment-rich regions. However, the physical processes by which sediments control this delocalization remain largely unresolved. Here we utilize high-resolution optical imagery to characterize surface rupture and OFD of the 2025 Mw 7.8 Myanmar earthquake, a supershear rupture event on a mature fault topping with thick sediments including the Quaternary alluvium and Irrawaddy Formation. Our results show averaging 32% OFD, far exceeding 13-19% expectation from global observations of such mature faults with simple geometry and supershear rupture speeds. Sediment-rich terrains along this rupture significantly amplify OFD to ~31-42%, nearly double the 19% observed in bedrock, and generate two highly diffused deformation sections lacking clear surface rupture. Dynamic rupture simulations incorporating variations in shear-wave velocity and frictional properties reproduce the observed OFD spectrum (from localized to fully delocalized deformation, revealing that plastic yielding of sediments dramatically delocalizes fault strain in the uppermost few hundreds of meters. We suggest such process should be integrated into models of shallow faulting and seismic hazard assessment in sediment-rich regions worldwide.
How to cite: Wei, S., Li, C., Zhai, P., Huang, Y., Klinger, Y., Ji, H., Ma, C., Bao, G., Ren, Z., Sun, K., Li, T., and Shan, X.: Sediment Yielding Amplifies Delocalization of Fault Deformation in the 2025Myanmar Earthquake, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15900, https://doi.org/10.5194/egusphere-egu26-15900, 2026.
The occurrence of seismic events can be modulated by external periodic stress perturbations, such as daily tidal stress and annual hydrological stress. Such periodic modulations are crucial for understanding earthquake triggering, yet their underlying physical mechanisms are not fully understood. Here, we find that ordinary earthquakes (OEs) and low-frequency earthquakes (LFEs) on the Central San Andreas Fault (CSAF) are more sensitive to the long-period hydrological and the short-period tidal loadings, respectively. These different frequency-dependent modulations suggest pore fluid diffusion during the noninstantaneous earthquake nucleation and confirm different nucleation times of OEs and LFEs. We constrain the depth-varying physical properties of the CSAF and reveal that fluid content distribution and loading conditions fundamentally control slow-to-fast fault slip behaviors. Our study provides an alternative perspective to understand earthquake nucleation by using the information in periodic seismicity modulations, which can be applicable to subduction zones where similar slip behavior transitions occur.
How to cite: Zhao, Z., Xue, L., Bürgmann, R., Heimisson, E. R., Lu, W., and Yue, H.: Tidal and hydrological seismicity modulations reveal pore fluid diffusion during earthquake nucleation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21919, https://doi.org/10.5194/egusphere-egu26-21919, 2026.
Earthquakes are among the most destructive natural hazards whose released energy can be quantified by their magnitude. Predicting how much energy will be released before the end of the rupture process represents a challenging question. The way earthquake ruptures grow, propagate and arrest determines the final size: small-to-moderate ruptures evolve in few seconds within few kilometers, while large-to-huge events develop in tens of seconds and several hundred kilometers. If the rupture process starts in the same way for small and large earthquakes, no deterministic prediction of the final size is feasible, until the process has completed. Instead, if the source mechanism starts differently from its beginning, real-time proxies can be measured on early radiated waves to discriminate the final event size. Here we show that the initial ground displacement grows differently for small and large earthquakes, based on the analysis of an unprecedented catalog of seismic waveforms from worldwide earthquakes. The result supports the hypothesis of early predictable magnitude for a wide range of different earthquakes in diverse geological settings. This study confirms that the initial growth of displacement can be used for a fast magnitude estimation, making it potentially feasible for future implementation in early warning systems.
How to cite: Longobardi, V., Colombelli, S., and Zollo, A.: The deterministic behaviour of earthquake rupture beginning, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5177, https://doi.org/10.5194/egusphere-egu26-5177, 2026.
The predictability of the final size of an ongoing rupture remains a fundamental open question in earthquake physics. If small and large earthquakes differ during their earliest stages, then information contained in the initial part of the source time function (STF) could provide a clue about the final rupture size, representing a major potential improvement for early warning systems. Testing this hypothesis using natural earthquakes is challenging because STFs are indirectly inferred, rupture dimensions are uncertain, and observational catalogs are incomplete.
To overcome these limitations, we built a new experimental catalog of laboratory earthquakes with a wide range of contained rupture lengths. Laboratory earthquakes were conducted using a biaxial apparatus holding PMMA plates, allowing controlled conditions and direct observations of rupture processes. We compute STFs using three independent approaches: (1) true STFs obtained via digital image correlation using a high-speed camera, (2) inferred STFs from quasi-static spatio-temporal slip inversions using 20 near-field accelerometers, and (3) approximate STFs estimated using a far-field acoustic sensor.
Our results show no robust relationship between final rupture length and the initial slope of the STF. Instead, we observe a relationship between the initial slope of the STF and the rupture velocity: events with higher initial rupture velocities exhibit steeper initial slope of the STF. Our results are supported by analytical results. These observations suggest that the initial growth of the STF mainly reflects rupture dynamics and nucleation processes rather than the ultimate size of the event. In this laboratory system, any information about final rupture length appears to emerge in the STF only once the rupture has grown to a length that is significant compared to its final size.
How to cite: Arzu, F., Xie, Y., Twardzik, C., Fryer, B., Paglialunga, F., Ampuero, J. P., and Passelègue, F.: What Do Early Source Time Functions Reveal About Rupture Dynamics in Laboratory Experiments? , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20158, https://doi.org/10.5194/egusphere-egu26-20158, 2026.
Seamount subduction is thought to strongly influence the slip behavior of megathrust earthquakes, yet its role in hosting fast or slow earthquakes remains controversial. Seamounts alter fault stress, fluid flow, and upper plate structure, introducing heterogeneity to the subduction system.
Here we investigate how a subducting seamount affects the earthquake cycle by modulating normal stress along the megathrust. We combine theoretical arguments based on energy balance (linear elastic fracture mechanics, LEFM) with numerical simulations. We use the efficient boundary element model FDRA, which simulates short-term earthquake cycles with rate-and-state friction.
We first examine shallow seamounts and identify three regimes: (1) downdip-nucleated earthquakes that propagate through the seamount, (2) seamount-nucleated earthquakes that break the entire fault, and (3) alternating earthquake behavior, where the seamount hosts small, seamount-confined events as well as larger, system-wide ruptures. The transition between regimes (1) and (2) is controlled by the seamount’s stress perturbation and its distance from the loading boundary. Rupture arrest, and the transition to regime (3), are explained by energy balance at the crack tip (LEFM). Partial ruptures at the seamount occur when fracture toughness, enhanced by normal-stress heterogeneity, exceeds the stress intensity factor. At sufficiently high stress amplitudes, seamounts host slow slip events that are controlled by the nominal nucleation dimension and the seamount width
Next, we extend the model to the downdip brittle–ductile transition at 50 km depth to test the effect of deeper seamounts. Seismic cycles are dominated by downdip nucleation, with most ruptures arresting before the seamount, though some propagate through it. As a result, stress at the seamount is repeatedly reset by downdip ruptures, preventing seamount nucleation. A simple theoretical estimate shows that, without heterogeneity, homogeneous friction makes seamount nucleation unlikely due to a tradeoff between rupture propagation and nucleation: high fracture energy limits rupture propagation but also increases the seamount nucleation length.
Finally, we account for frictional heterogeneity by implementing multiple hierarchical slip-weakening distance profiles and examine how this controls seismic behavior. Our results show that seamounts, even with small stress perturbations and at different depths, consistently promote slow slip in their stress shadow and increase earthquake activity at the stress shadow’s edges. Seamounts can act as rupture barriers, occasionally facilitate large system-wide ruptures, but they more commonly host smaller partial ruptures.
Overall, our work demonstrates that seamounts can produce a rich variety of slip behavior, including slow slip, earthquake nucleation, partial and full ruptures, reconciling diverse observations across subduction zones worldwide. These regimes are well understood in terms of normal stress heterogeneity and prestress levels. A single seamount can produce different slip patterns throughout the seismic cycle, with important implications for seismic hazard.
How to cite: Verwijs, R. and Cattania, C.: Linking Fast and Slow Earthquakes: The Role of Subducting Seamounts, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12975, https://doi.org/10.5194/egusphere-egu26-12975, 2026.
This study shows evidence based on observations of near-fault ground motions and surface offset that regions with larger-than-average surface offset exhibit weaker ground motions for frequencies above 0.5 Hz. This negative correlation of surface offset and high-frequency ground motion is inconsistent with current scaling in kinematic rupture generators. Using rupture dynamic simulations with a linear slip-weakening rheology model combined with observed data enables us to define an input parameter space that is consistent with the observations. Given the multi-parameter nature of rupture dynamics, we focus on just two parameters: stress drop and the slip-weakening distance, Dc. Under this framework, the observed scaling can be explained if the stress drop is positively correlated with the slip-weakening distance. We explore the implications of our findings in kinematic source modeling constrained by our rupture dynamic simulations. We conclude that the ratio between the time of positive acceleration and the total rise time is negatively correlated with the total rise time, which contrasts with the current assumption of keeping this percentage fixed. Moreover, this study shows that regions with larger-than-average static stress drops tend to radiate weaker high-frequency energy and stronger low-frequency energy.
How to cite: Pinilla-Ramos, C. and Abrahamson, N.: Constraining Rupture-Generator Scaling Using Measured Surface Offsets, Near-Fault Ground Motions and Rupture Dynamic Simulations, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15068, https://doi.org/10.5194/egusphere-egu26-15068, 2026.
After more than 5 years of design, preparation and build-out, the Earthquake Physics Testbed at the Bedretto Underground Laboratory for Geosciences and Geoenergies ('BedrettoLab') is going into full operation in spring 2026. The testbed is being built for the Fault Activation and Earthquake Rupture (FEAR) project, around a carefully selected and heavily instrumented target fault zone at more than 1km depth. The fault is a steeply dipping, structurally immature fault and fracture zone, which, in the current stress field has oblique-normal faulting kinematics. To facilitate instrumentation, we have excavated a 110m long fault-parallel tunnel at a horizontal distance of 40 m from the fault. Using this access tunnel, we are densely instrumenting a volume of ca 100 x 100 x 200 m3 around the target fault zone, by placing over 200 sensors, of 25 different sensor types, and several hundred metres of fibre optics sensing cables, in over 40 boreholes.
Once completed, we will use multi-packer systems in 3 fault-crossing stimulation boreholes to re-activate the target fault with fluid injections. In a series of experiments we attempt to trigger dynamic ruptures with magnitudes of ~1.0, i.e. ruptures with fault dimensions of 10 - 100m. The goal is to resolve and study the micro-physical processes that govern fault preparation, earthquake nucleation, rupture dynamics and termination, as well as post-seismic processes, with a resolution and sensitivity that is not achievable for natural, tectonic earthquakes. In this talk we present the first results from the 'FEAR-2' experiment, the first experiment where we inject directly into the main segment of the target fault zone, and present the plans for more experiments in 2026 - 2027.
How to cite: Meier, M.-A., Selvadurai, P., Gischig, V., Hertrich, M., Rinaldi, A., Zappone, A., Tinti, E., Spagnuolo, E., Jalali, R., Amann, F., Cocco, M., Wiemer, S., and Giardini, D. and the Bedretto and FEAR teams: Fault Activation and Earthquake Ruptures at the BedrettoLab, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17270, https://doi.org/10.5194/egusphere-egu26-17270, 2026.
The left-lateral East Anatolian Fault (EAF) is one of the most active intracontinental plate-boundary faults, along with the right-lateral North Anatolian Fault (NAF), accommodating the westward movement of the Anatolian plate in the Eastern Mediterranean Region. The historical seismic records, indicating the large-magnitude earthquakes caused by the East Anatolian Fault Zone (EAFZ), conflict with the region’s relative tectonic silence during the instrumental period. The largest known historical earthquakes along the EAFZ occurred in 995 (Ms 7 - 7.8), 1114 (M > 7.8), 1408 (Ms 7.2), 1513 (M > 7.4), 1789 (Ms > 7), 1822 (Ms > 7.4), 1872 (Ms > 7.2), 1874 (Ms > 7.1), 1893 (M > 7.1), 1905 (Ms 6.8), 1971 (Ms 6.8), 2020 (Mw 6.75) and 2023 (Mw 7.5). The 24 January 2020 Mw 6.7 Doğanyol-Sivrice Earthquake and the 6 February 2023 Mw 7.8 Kahramanmaraş Earthquake Doublet have shown that the EAFZ, located in the middle of the continental collision zone, poses a significant potential to generate catastrophic earthquakes despite its long quiescence-period. Following the 2020 Mw 6.7 Doğanyol-Sivrice earthquake, studies that particularly focusing Coulomb stress change distribution indicated that the stress transfer along the EAF towards the northeast of Lake Hazar, in particular to the Palu, Ilıca, and Karlıova segments. Similarly, stress transfer following the February 6, 2023 Kahramanmaraş earthquakes was towards both southwest, i.e., to the Amanos and Hacıpaşa segments, and to the northeast of the EAF. Although M<4 aftershocks from both activities extended to the end of the Karlıova segment where the Karlıova triple junction joins the NAF, there have been no M>5 earthquakes in the Palu, Ilıca, and Karlıova segments since 2010. Therefore, we selected the region covering these segments for the investigation since it is the relatively seismically inactive area of the EAF. Our major objective is to understand the impact of the 2020 Doğanyol-Sivrice and 2023 Kahramanmaraş earthquakes and subsequent post-seismic deformation period on the silent region through the analyses of InSAR (SBAS) and GNSS time series, incorporated with analyses of coseismic deformation, Coulomb Stress Change, and b-value variation. To achieve this aim, ISCE2 and Mintpy utilities were used in the calculation of the InSAR time-series and GAMIT/GLOBK is used to construct GNSS time-series. The results from multiple-data analyses enable a comprehensive understanding of the tectonic setting as well as to understand whether the segments in the region are locked or experiencing any creep activity.
How to cite: Zoroğlu, Ç. S., Kaya Eken, T., Gedik, M., Eken, T., and Özener, H.: Impact of the 2020 Elazığ and 2023 Kahramanmaraş Earthquakes on the Palu–Ilıca–Karlıova Segments using InSAR, GNSS, and Seismotectonic Analyses, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16169, https://doi.org/10.5194/egusphere-egu26-16169, 2026.
On January 1, 2024, a Mw 7.5 earthquake struck the northern Noto Peninsula in Japan. Prior to the mainshock, an intense seismic swarm persisted for over three years—driven by fluid propagation and accumulation—and led to two large foreshocks: the Mj 5.4 event in 2022 and the Mj 6.5 event in 2023. High-resolution earthquake catalogs are essential for elucidating earthquake nucleation processes, but they provide only a limited view of the detailed faulting mechanisms, fault structures, and spatiotemporal stress changes involved. In contrast, focal-mechanism solutions for small earthquakes (e.g., M < 3)—which are challenging to obtain using traditional methods when station coverage is sparse—provide subtle, qualitative constraints on fault orientations and stress changes. In this study, we aim to deepen our understanding of the Noto Peninsula earthquake’s long-term nucleation by characterizing focal mechanisms of small foreshocks to reveal detailed stress evolution and infer associated fault structures.
We employ the recently developed, cross-correlation–based double-ratio inversion method FocMecDR to determine focal mechanisms of small earthquakes preceding the Mw 7.5 Noto Peninsula earthquake. Analogous to the double-difference concept in earthquake location, FocMecDR uses a reference event with a known mechanism (i.e., strike, dip, and rake) and inverts nearby target events by (1) matching relative polarities for pairs of events via waveform cross-correlation and (2) minimizing the misfit between observed and theoretical P/S amplitude double ratios for pairs of events. We will first briefly introduce this method and validate its effectiveness using the well-studied 2019 Mw 6.4 Ridgecrest earthquake sequence. For the Mw 7.5 Noto Peninsula earthquake sequence and its foreshocks, we focused on the period from January 2020 to March 2024 using the FocMecDR and 135 F-net focal mechanisms as templates, and determined focal mechanisms for more than 1,000 M > 2 earthquakes. The detailed variations in focal mechanisms delineate the dipping angles of fine fault structures and the spatiotemporal evolution of stress. Most interestingly, we found reversed normal-faulting earthquakes following large thrust events. In this presentation, we will report these results and discuss the detailed nucleation process before the Mw 7.5 mainshock.
How to cite: Zhang, M. and Kato, A.: Characterization of Focal Mechanisms for Small Earthquakes Preceding the Mw 7.5 Noto Peninsula Earthquake, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5734, https://doi.org/10.5194/egusphere-egu26-5734, 2026.
On December 18, 2023, an Ms6.2 earthquake struck Jishishan County, Linxia Prefecture, Gansu Province, China. The earthquake occurred in the boundary area of Qilian orogenic belt and Bayanqala block in the northeast margin of Tibetan Plateau. Near the epicenter, the Laji Mountain fault, the Riyueshan fault and the north margin of the West Qinling fault developed. In this study, 598 aftershocks of the Ms6.2 earthquake sequence in Jishishan were relocated using the double difference positioning method. The main earthquake location was 102.826°E, 35.743°N, and the focal depth was 12.3 km. The main moment magnitude is 6.1, and the strike, dip and slip Angle of the fault plane are 162°, 44° and 122°, respectively. Combined with the results of relocation and focal mechanism solution, it is believed that the seismic fault of this earthquake is a hidden NNW-SSE trending NE-dip fault between the northern and southern margin faults of Laji Mountain. The fault located at the main earthquake mainly leans to the east, the aftershock extends to the northwest, and the fault changes from east dip to vertical dip to west dip to the north, with a transitional zone in between. The transformation form presents a "fan" shape, which intuitively shows the complexity of the tectonic environment in this area. From the source rupture inversion, the rupture is mainly an elliptical area with a long axis of about 10 km and a short axis of about 6 km in the northwest direction of the source, with a maximum error momentum of about 40 cm, located at a depth of about 14.5 km underground. From the perspective of the seismic rupture direction, the rupture mainly propagates along the direction of striking NWW, and the rupture maximum value appears at 2.2 seconds. The rupture velocity is about 1.5 km/s, and the rupture is mainly unilateral. The extreme earthquake area of strong ground motion estimated by finite fault model is up to Ⅸ degrees, which is consistent with the seismic field investigation results.
How to cite: Luo, Y. and Zhu, Y.: The seismic tectonics of the MS6.2 Jishishan Earthquake in Gansu Province on the northeastern margin of the Tibetan Plateau were analyzed based on the earthquake relocation, focal mechanism solution, and rupture process, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9316, https://doi.org/10.5194/egusphere-egu26-9316, 2026.
The repeating earthquake method constrains repeated rupture processes on the same or adjacent source patches of a fault by identifying small-magnitude earthquake events with highly similar source locations, focal mechanisms, and waveforms. This approach effectively captures information on seismic velocity variations and fault stress evolution and has been widely applied to studies of fault slip rates, strain accumulation, and earthquake preparation processes. The NE-striking Zhaotong-Ludian Fault Zone, located in the eastern segment of the Sichuan-Yunnan border region, has exhibited pronounced thrusting combined with right-lateral strike-slip motion since the Late Quaternary, shows a high degree of fault locking and significant strain accumulation potential, and hosted the 2014 Ludian MS 6.5 earthquake, making it an ideal case for investigating fault-zone velocity variations and earthquake preparation mechanisms using repeating earthquakes. In this study, we collected near-field three-component continuous seismic waveform data from January 2018 to March 2021 in the Zhaotong-Ludian Fault Zone, Yunnan Province, and identified a group of repeating earthquake events located on the eastern side of the fault zone through waveform cross-correlation analysis to investigate velocity structure variations within the fault zone. Analysis of repeating earthquake waveforms recorded at different stations shows that the three-component waveforms recorded at station YIL, which is located on the eastern side of the fault zone, exhibit a high degree of similarity, whereas waveforms recorded at station YUD on the western side of the fault zone remain generally consistent but display subtle differences within approximately 2-5s after the P-wave arrival. We further constrained seismic velocity variations within the fault zone by comparing observed waveforms of the repeating earthquakes with synthetic waveforms generated using a two-dimensional finite-difference method. The results indicate that when the P-wave velocity decreases by approximately 4% at depths of 6-12 km in the central portion of the fault zone, the synthetic waveforms successfully reproduce the phase delays observed in the recorded waveforms, with good agreement in both time shifts and waveform morphology. These findings not only quantitatively constrain the magnitude and spatial distribution of velocity variations within the fault zone, but also demonstrate the feasibility of identifying localized changes in velocity structure using waveform differences of repeating earthquakes, and they provide important insights into fault-zone fluid processes and their role in earthquake preparation.
How to cite: Wang, B., Zhou, Y., and Feng, J.: Determination of velocity structure variations within the Zhaotong-Ludian Fault Zone based on Repeating Earthquakes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6445, https://doi.org/10.5194/egusphere-egu26-6445, 2026.
Earthquakes radiate varying amounts of high-frequency energy, reflecting differences in source dynamics, propagation and attenuation, and near-station site effects. Building on results from the Ridgecrest Stress Drop Validation Exercise, which revealed large uncertainties in stress drop estimates, we apply a new data-driven approach to measure differences in seismic radiation directly from the observations. We compute a ratio of high-frequency to low-frequency amplitude from individual spectra. By empirically correcting path, station, and magnitude effects, we measure the relative amount of high-frequency radiation in earthquakes compared to nearby calibration events. Our results show that this normalized spectra ratio is correlated with earthquake stress-drop estimates from previous studies of the 2019 Ridgecrest aftershock sequence, suggesting that it can be used to infer differences in source dynamics. We expand this approach to examine over 30 years of California seismicity, including hundreds of thousands of earthquakes, and identify spatial differences in high-frequency radiation and inferred source mechanics. Spatial variations in high-frequency radiation occur over both local and regional scales, and are visible within high-seismicity regions, including Parkfield, Geysers, and Mammoth Lakes. Our large-scale study of spatial differences in earthquake radiation offers an observation-based alternative to traditional stress-drop estimation methods, and we will discuss its implications for fault properties and strong ground motion prediction in California.
How to cite: Vandevert, I., Shearer, P., and Fan, W.: Examining Spatial Variations in California Earthquake Dynamics Using a High- to Low-Frequency Spectral Ratio, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-8401, https://doi.org/10.5194/egusphere-egu26-8401, 2026.
Joint seismic and geodetic analyses reveal that the 2025 Mw 7.8 Mandalay, Myanmar earthquake ruptured ~510 km of the Sagaing Fault, including a sustained supershear rupture extending ~450 km along the southern branch and a shorter ~60 km subshear rupture to the north. The supershear nature of the southern rupture is independently confirmed by the observation of far-field Mach waves, comparisons between near-fault fault-parallel and fault-normal velocity components, and picks of ground-displacement onset times. This exceptionally long supershear rupture produced widespread building collapse, landslides, and soil liquefaction documented by satellite observations, highlighting the severe damage potential of such rupture modes in urban environments. We propose that the persistent supershear propagation was enabled by the fault’s linear geometry, prolonged interseismic quiescence, favorable energy ratio, and pronounced bimaterial contrasts across the fault interface. Together, these results emphasize the critical roles of fault structure, stress accumulation, and material contrasts in controlling rupture dynamics, and demonstrate that large-scale supershear propagation can occur on interplate continental strike-slip faults.
How to cite: Xu, L., Meng, L., Yunjun, Z., Yang, Y., Wang, Y., Hu, C., Weng, H., Xu, W., Su, E., and Ji, C.: Bimaterial Effect and Favorable Energy Ratio Enabled Supershear Rupture in the 2025 Mandalay Quake, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3206, https://doi.org/10.5194/egusphere-egu26-3206, 2026.
Despite recent advances from real observations, laboratory experiments and numerical modelling, the mechanisms governing earthquake generation and wave propagation are still not fully understood. Theoretical analyses and laboratory experiments increasingly show that seismic ruptures begin with a process of quasi-static slip accumulation over a limited region of the fault (referred to as the preparatory phase). Here, when a critical dimension (or area) is reached, the slip rapidly accelerates (referred to as the break-out phase) and creates a rupture front which finally propagates dynamically. While the breakout phase is observed at laboratory scale, no direct evidence is available at the scale of real-earthquake data. The unresolved question is whether the breakout phase has an influence on the final size of the forthcoming event. In other words, it remains unclear whether all earthquakes begin through a similar process—characterized by the exceedance of a yield stress and influenced by local frictional properties or geometric complexities of the fault surface—with the rupture extent determined during propagation, or whether fundamentally different initiation mechanisms govern the generation of small and large events. Within the framework of the ERC FORESEEING project (https://www.foreseeing.eu/), we use the P-waves to shed light onto the mechanism of generation of seismic ruptures and to constrain the role of the parameters involved in the process. We investigate the onset of P-waves across multiple datasets, focusing on natural earthquakes with magnitudes Mw 1–4 from four well-instrumented regions: the Campi Flegrei region (Southern Italy), the Irpinia Near Fault Observatory (Southern Italy), the TABOO network (Central Italy), and The Geysers geothermal field (USA), for a total of thousands of events and available waveforms.
Following the approach of Longobardi et al. (2025), we analyse the behaviour of the low‐pass displacement vs. time curve (LPDT). We found that LPDT curves grows differently for micro (Mw 1-2) to small earthquakes (Mw 2-4), following a similar trend as observed for worldwide moderate-to-large events (Longobardi et al. 2025). For a limited number of events, we extended the analysis to laboratory scale - 300 mm fault length - experiments, where we use acoustic signals to investigate the relation between the LPDT and the seismic source allowing a direct comparison between elastic waves over a wide range of spatial and temporal scales. We will discuss the scaling of LPDT curves across diverse seismic environments and magnitude ranges, and its potential use for rapid source characterization, in the context of Earthquake Early Warning applications.
How to cite: Colombelli, S., Longobardi, V., Aretusini, S., Cornelio, C., Kiss, A., Spagnuolo, E., and Zollo, A.: Scaling of rupture initiation from P-wave onset: insights from earthquakes and laboratory experiments, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5024, https://doi.org/10.5194/egusphere-egu26-5024, 2026.
A long-standing debate in geophysics concerns the moment–duration scaling of fast and slow earthquakes. While many studies suggest that slow slip events (SSEs) follow a linear moment–duration relationship, in contrast to the cubic scaling typical of regular earthquakes, some observational and modeling studies have reported cubic-like scaling in some SSEs, raising questions about the physical origin of these differences. In this study, we investigate the scaling properties of SSEs using kinematic simulations constrained by empirical source scaling relationships specific to slow slip, combined with stochastic kinematic approaches widely used for regular earthquake rupture modeling. The simulations are conducted on realistic fault geometry in the Cascadia subduction zone and incorporate kinematic constraints characteristic of slow slip. Synthetic SSE scenarios are generated over a wide range of moments and rupture dimensions, allowing systematic exploration of moment–duration behavior without prescribing rupture duration a priori. Our results are consistent with observations and show that the total duration of the simulated SSEs lies near the upper envelope of a cubic scaling trend (M ∝ T³) at smaller moments and gradually transitions toward a linear scaling (M ∝ T) with increasing moment magnitude. When event duration is identified using threshold-based criteria, the resulting moment–duration scaling appears predominantly linear. This finding suggests that biases introduced by observational criteria influence the inferred scaling relationships, providing an explanation for why some studies report linear scaling whereas others report cubic scaling. Furthermore, these results suggest that slow slip events involve rupture processes fundamentally distinct from those of regular earthquakes, as their apparent duration and scaling behavior emerge from kinematic constraints characteristic of slow slip.
How to cite: Sun, Y.-S., Melgar, D., and Thomas, A.: Unraveling Scaling Properties of Slow Slip Events through Kinematic Simulations, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16423, https://doi.org/10.5194/egusphere-egu26-16423, 2026.
During an earthquake, fault slip and the passing of seismic waves perturb the stress field surrounding the ruptured fault or faults. Aftershocks with a variety of focal mechanisms have been used to interpret a complete stress drop that has permitted principal stresses to swap orientations. We test if this is required or if aftershock heterogeneity may be promoted by moderate stress decreases and principal stress rotations, in the absence of a complete stress drop and principal stress swapping. Three-dimensional (3D) simulations of dynamic earthquake ruptures at high temporal resolution provide a pathway for testing these alternatives, but are challenged by the computational cost and storage space required to run and analyze such models at high enough spatial and temporal resolutions to study co-seismic stress evolution. We were supported by the Geo-INQUIRE Transnational Access program to run a suite of megathrust earthquake scenarios based on the 2004 Sumatra-Andaman earthquake on CINECA’s Leonardo high performance computing (HPC) platform booster partition, currently ranked 10th in the Top500, the list of the fastest supercomputers in the world. These models are run with SeisSol, which solves for dynamic rupture on complex, three-dimensional faults and seismic wave propagation through heterogeneous media. Initial conditions for these scenarios vary in the amount of pore fluid pressure and how it is distributed with depth, the relative magnitudes of the principal stresses, and initial stress heterogeneity. As a result, the modeled earthquakes vary in magnitude, average stress drop magnitude, the distribution of stress drop along the main fault, and locations of peak slip and slip rate. We document the stress field at a central position along the rupture as it evolves from nucleation to earthquake end and share results for how different pre-earthquake conditions influence stress rotation magnitudes and orientations. While the results do not rule out complete stress drop and principal stress swapping as an explanation for aftershock heterogeneity, we find that stress rotations that occur along the megathrust and in the hanging wall support thrust, normal and strike-slip failure, even when a complete stress drop is not achieved. These models push the limits of HPC experimental dataset storage, transfer and analysis. We utilize the new Geo-INQUIRE Simulation Data Lake (SDL), which provides not only capacity to store terabytes of synthetic data, but also allows open and FAIR (Findable, Accessible, Interoperable, Reusable) sharing of the results through Digital Object Identifiers (DOIs) for each dataset and the accompanying model files.
How to cite: Madden, E., Christadler, I., Ulrich, T., and Gabriel, A.-A.: Earthquake rupture models with very high spatial and temporal resolution: Data management and insight into co-seismic stress evolution, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12706, https://doi.org/10.5194/egusphere-egu26-12706, 2026.
In seismology, a misfit function is commonly used to quantify the similarity between recorded and model-predicted waveforms. In comparison with the L2 norm, the Wasserstein distance (W2 norm) mitigates the “cycle skipping” problem and offers a more effective waveform similarity measurement for optimization purposes. The W2 norm avoids local minima and enables efficient gradient-based methods to be adopted in waveform inversions. In this study, we develop an algorithm based on W2 norm for multi-point-source models of large earthquakes. We employ Basin Hopping and L-BFGS-B for global and local optimizations, respectively, to invert for the locations, times, moments, and focal mechanisms of multiple point sources to describe the rupture processes of large earthquakes.We develop a novel method that combines W2 and L2 norms to avoid non-uniqueness and enhance the robustness and accuracy of the inversion process. Comprehensive synthetic tests are conducted to demonstrate the good performance in waveform fitting accuracy, computational efficiency, and inversion stability for multi-point-source parameters. Application to the 2016 Mw 7.0 Kumamoto earthquake shows promising results in effectively balancing accuracy and computational demands while characterizing the event's complex rupture process. Our inversion method provides a rapid and effective multi-point-source inversion tool that can deliver reliable constraints on earthquake rupture processes.
How to cite: Yuan, Y. and Yue, H.: Wasserstein Distance (W2) Gradient-based Multi-Point-Source (MPS) Inversion, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21439, https://doi.org/10.5194/egusphere-egu26-21439, 2026.
An earthquake record is the convolution of source radiation, path propagation and site effects, and instrument response. Isolating the source component requires solving an ill-posed inverse problem. Whether the instability of inferred source parameters arises from varying properties of the source, or from approximations we introduce in solving the problem, remains an open question.
Such approximations often derive from limited knowledge of the forward problem. The Empirical Green’s function (EGF) approach offers a partial remedy, by approximating the forward response of large events using the records of smaller events. The choice of the « best » small event drastically influences the properties estimated for the larger earthquake. Discriminating variability in source properties from epistemic uncertainties, stemming from the forward problem or other modeling assumptions, requires us to reliably account for, and propagate, any bias or trade-off introduced in the problem.
We propose a Bayesian inversion framework that aims at providing reliable and probabilistic estimates of source parameters (here, for the source-time function or STF), and their posterior uncertainty, in the time domain. We jointly solve for the best EGF using one or a few small events as prior EGF. Our approach expands on DeepGEM, an unsupervised generalized expectation-maximization framework for tomography (Gao et al., 2021). We demonstrate, with toy models and various applications to mainshocks of Mw ranging from ~4 to 6.3, the potential of DeepGEM-EGF to disentangle the variability of the seismic source from biases introduced by modeling assumptions.
How to cite: Ragon, T., Gao, A., and Ross, Z.: DeepGEM-EGF: A Bayesian strategy for joint estimates of source-time functions and empirical Green's functions, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1504, https://doi.org/10.5194/egusphere-egu26-1504, 2026.
Slow slip events (SSEs), a type of slow earthquakes, generally recorded by the Global Navigation Satellite System (GNSS), play an important role in releasing strain in subduction zones. Understanding the relationship between SSEs and damaging earthquakes in nearby velocity-weakening portions of the plate interface could provide a valuable tool for forecasting large earthquakes, thus aiding in hazard mitigation. Detecting accurately the occurrence times of SSEs is one prerequisite to illuminate their interactions with large earthquakes. However, robust detection methods remain limited. Most undetected SSEs in GNSS data are short-term SSEs, i.e. SSEs with short durations ranging from days to weeks, since the amplitude changes in the GNSS data trend from short-term SSEs are somewhat small, close to (or even lower than) the background noise. Therefore, more urgent efforts should be devoted to developing an automated detection method for short-term SSEs in GNSS data.
Both observed and simulated GNSS data containing SSEs exhibit a typical piecewise nonlinear trend. In periods without SSEs, the data generally follow a noisy linear process. When an SSE occurs, the trend shifts to a different trajectory and returns to its original state once the event concludes. In this context, the start and end of an SSE correspond to change points in statistics, which refer to the times when the underlying dynamics of the signal transition between regimes. Thus, detecting SSEs in GNSS data can be formulated as a change point detection problem for piecewise nonlinear signals. However, developing a nonparametric change point detection method specifically for SSEs is challenging because constructing a suitable contrast function requires knowledge of the exact piecewise structure, which is currently unknown. This limitation also prevents existing change point detection methods from being directly applied to detect SSEs.
In this study, we propose Singular Spectrum Analysis Isolate-Detect (SSAID), a novel change-point detection method for automatically estimating the start and end times of short-term SSEs in GNSS data. A key advantage of SSAID is that it does not require prior knowledge of the specific form of the underlying SSE signal. The core idea of SSAID is to obscure the differences between the nonlinear SSE signal and a piecewise-linear model, allowing existing change-point detection techniques for piecewise-linear signals to be directly applied for SSE detection. We evaluate SSAID through extensive simulations on both synthetic and observed SSE data, demonstrating its robustness across varying noise levels and its superior performance compared to two existing approaches: linear regression with AIC and the L-1 trend filtering method. Finally, we confirm the effectiveness of our detections in observed GNSS data via the co-occurrence of non-volcanic tremors, hypothesis tests, and fault estimation.
How to cite: Ma, Y., Anastasiou, A., and Montiel, F.: A novel statistical method for detecting short-term slow slip events in GNSS time series, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-325, https://doi.org/10.5194/egusphere-egu26-325, 2026.
Posters virtual: Tue, 5 May, 14:00–18:00 | vPoster spot 1b
EGU26-13656 | ECS | Posters virtual | VPS24
Moment tensor analysis and uncertainty quantification of local earthquake events: tectonic implication in the northwestern Himalayan regionTue, 05 May, 14:12–14:15 (CEST) vPoster spot 1b
Regular monitoring of small to moderate sources of continuous earthquake events in the complex tectonics of Himalayan region helps in clearly defining the ongoing seismotectonic process. The study of moment tensor inversion to decipher the fault planes responsible for current seismic activity in the Kishtwar region of Northwest part of Himalaya has been undertaken by establishing a six-station network in 2022 and among them 15 events of shallow origin with magnitude ranging from ML ~ 3.0 to 4.0 occurred in the local region of seismic network are used for the moment tensor inversion. A few number of studies didn’t able to clearly demarcate the actual scenario of seismotectonics in the northwest part of Himalaya due to its difficult terrain and complex geology. This area has been studied for fault plane solution by a software package ISOLA based on MATLAB programming environment. The source inversion is performed via iterative deconvolution method and synthetic seismogram is generated through green’s function computation via discrete wavenumber method using the regional crustal velocity model. However, the inversion is performed at several trial source position and at various frequency bands based on the epicenter distance and the magnitude of earthquake to find the best solution resulting from the maximum correlation between the recorded and synthetically generated waveforms. A 2D space-time grid search is performed for determining the optimal time and positon of earthquake generation. Perhaps calculating source parameters such as moment magnitude, centroid depth and fault parameters equally with describing uncertainty quantities such as variance reduction factor and condition number will deliver the reliability and stability to the solution. A strong follow-up uncertainty quantification can justify the best estimated fault plane solution. Quality of earthquake event can be calculated through their DC and CLVD percentage and maximum & minimum compression stress direction. Focal mechanism solution of these events following thrust with strike-slip focal mechanism and represents the compressional regime in north-northeastern direction. The centroid depth obtained by moment tensor inversion of all events falls within the depth zone of Main Himalayan Thrust (MHT) suggesting seismicity is concentrated along the major detachment in the region.
How to cite: Tiwari, S. and Gupta, S. C.: Moment tensor analysis and uncertainty quantification of local earthquake events: tectonic implication in the northwestern Himalayan region, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13656, https://doi.org/10.5194/egusphere-egu26-13656, 2026.
EGU26-6568 | ECS | Posters virtual | VPS24
Scaling of Stress Drop with Rate-and-State Frictional Parameters in Spring-Block ModelsTue, 05 May, 14:15–14:18 (CEST) vPoster spot 1b
Numerical simulations of earthquake cycles provide essential insights into fault mechanics and the physical interpretation of frictional parameters. Here, we utilize a spring-block system governed by rate-and-state friction to systematically compare earthquake cycle behaviors under quasi-dynamic and fully dynamic conditions. Our simulations demonstrate that for both approaches, the static stress drop, dynamic stress drop, and peak stress scale linearly with the logarithm of the loading rate [ln(Vpl/V0)]; however, the scaling coefficients are distinct and are modulated by both frictional parameters and the system stiffness. Specifically, we observe stress overshoot during the coseismic phase in dynamic models, contrasting with the undershoot observed in quasi-dynamic simulations. Additionally, parameter sweeps reveal that stress drops decrease as the stiffness ratio kc/k increases. This study highlights the importance of the inertial term effect in interpreting earthquake cycle behaviors.
How to cite: Chai, L. and Hu, F.: Scaling of Stress Drop with Rate-and-State Frictional Parameters in Spring-Block Models, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6568, https://doi.org/10.5194/egusphere-egu26-6568, 2026.
