Journal of Geophysical Research: Solid Earth最新文献

{"title":"Teleseismic Rayleigh Wave Helmholtz Tomography in Northeastern Tibet Using Physics-Informed Neural Networks","authors":"Yunpeng Chen,&nbsp;Sjoerd A. L. de Ridder,&nbsp;Sebastian Rost,&nbsp;Zhen Guo,&nbsp;Yongshun Chen,&nbsp;Lin Gan","doi":"10.1029/2026JB034179","DOIUrl":"https://doi.org/10.1029/2026JB034179","url":null,"abstract":"<p>In this study, we apply a physics-informed neural network (PINN)-based teleseismic Rayleigh wave Helmholtz tomography (pinnTHT) to investigate the crustal and upper mantle structure beneath the northeastern Tibetan Plateau. The method incorporates the Helmholtz equation directly into the loss function, allowing phase velocity, amplitude, and traveltime fields to be jointly constrained. We represent the physical fields as continuous, grid-free functions whose spatial derivatives are evaluated by automatic differentiation rather than by finite differences on a fixed grid. We apply this approach to teleseismic surface wave data recorded by a dense seismic array and analyze Rayleigh wave phase velocities at periods of 20–80 s. Our results reveal significant lateral heterogeneity in velocity structure that correlates well with major tectonic features across the study area. The method achieves reliable resolution using only approximately 20% of the observational data compared to traditional approaches, and a synthetic ground-truth test confirms that pinnTHT recovers a known velocity model more accurately than conventional Helmholtz tomography applied to the full data set. Comparisons with ambient noise tomography results at overlapping periods show consistent velocity anomaly patterns, indicating that the combination of earthquake and ambient noise data provides a systematic understanding of phase velocity structure across multiple periods. These results demonstrate that PINN-based teleseismic Helmholtz tomography offers a memory efficient and robust approach for investigating deep Earth structure, particularly beneficial in regions with sparse or unevenly distributed data.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149048197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonuniform Mantle Suture Beneath Northern Tibet Revealed by Helium Isotopes and Attention-Based Machine Learning: Implications for Crustal Rheology and Growth of the Tibetan Plateau","authors":"Yingchun Wang,&nbsp;Xintian Li,&nbsp;Shuang Liao,&nbsp;Yi Wang,&nbsp;Simon Klemperer,&nbsp;Ji Zhang,&nbsp;Yinlei Hao,&nbsp;Jiao Tian,&nbsp;Yazhou Zhao,&nbsp;Xiaocheng Zhou,&nbsp;Dawei Liao,&nbsp;Yinhui Zuo,&nbsp;Yanlong Kong,&nbsp;Zhonghe Pang,&nbsp;Hikaru Iwamori","doi":"10.1029/2025JB033474","DOIUrl":"https://doi.org/10.1029/2025JB033474","url":null,"abstract":"<p>The tectonic evolution of northern Tibet is crucial for unraveling the uplift and growth mechanisms of the Qinghai–Tibet Plateau. However, inconsistent geophysical observations have led to long-standing controversies over whether the Asian lithosphere beneath northern Tibet is undergoing underthrusting or southward subduction. In this study, we compiled 846 helium isotope (<i>R</i>_<i>C</i>/<i>R</i>_<i>A</i>) data points from across the Qinghai–Tibet Plateau and developed a two-stage gradient boosted tree–probabilistic fusion network (2S-GBTPFN) method that integrates geological, geophysical, geochemical, and hydrological parameters. The results show that attention-based machine learning (ML) can reveal the spatial pattern of helium isotope ratios across the plateau and delineate a helium boundary in northern Tibet (<i>R</i>_<i>C</i>/<i>R</i>_<i>A</i> &gt; 0.1 <i>R</i>_<i>A</i>). This boundary is interpreted as the geochemical expression of a mantle suture and is consistent with independent geophysical observations. The newly identified helium boundary reveals a nonuniform rheological boundary across the Kunlun suture and indicates uneven, limited southward subduction of the Asian lithosphere beneath the northern Tibetan Plateau. When combined with evidence for subduction beneath southern Tibet, our results support a geodynamic framework involving dual-slab subduction, multistage lithospheric delamination, and asthenospheric upwelling. These findings provide new geochemical evidence for the oblique subduction processes that have contributed to the uplift and growth of the Qinghai–Tibet Plateau.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149047871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Likelihood-Free Framework for Seismic Forecasting Models: Application to Incomplete ETAS Model via Simulation-Based Inference","authors":"P. Bountzis,&nbsp;G. Petrillo,&nbsp;E. Lippiello","doi":"10.1029/2026JB034110","DOIUrl":"https://doi.org/10.1029/2026JB034110","url":null,"abstract":"<p>Recent advances in deep-learning-based earthquake detection have revolutionized seismology, producing high-resolution catalogs complete down to very low magnitudes. While these data sets offer an unprecedented view of seismic triggering, their massive scale and inherent short-term incompleteness pose a major challenge for traditional statistical analysis. In this context, identifying the optimal model parameters for forecasting becomes challenging. Indeed, the standard procedure of maximizing the likelihood is often unfeasible, due to both the massive volume of data and the fact that observations are strongly biased by incompleteness. To address this, here we reformulate parameter estimation as a likelihood-free, simulation-based inverse problem. We introduce a general framework that bypasses the explicit evaluation of the likelihood by combining Approximate Bayesian Computation with stochastic optimization. The method performs inference by identifying the parameter set that minimizes the discrepancy between the observed data and a stochastic generative model, using summary statistics that capture the essential spatio-temporal features of the triggering process. We validate this approach using the incomplete Epidemic-Type Aftershock Sequence (ETAS) model, which explicitly incorporates time-dependent detection thresholds. Tests on synthetic catalogs demonstrate that the framework robustly recovers the underlying physical parameters even under severe incompleteness, revealing systematic biases in standard ETAS estimates that ignore detection limitations. Notably, the proposed method exhibits sub-quadratic computational scaling with catalog size, enabling the analysis of the vast data sets produced by modern monitoring networks. Our approach provides a scalable and flexible solution for the next generation of seismic forecasting.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JB034110","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149146739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic Dual-Layer Equivalent Sources on the Sphere","authors":"Arthur Siqueira-Macedo,&nbsp;Leonardo Uieda,&nbsp;India Uppal","doi":"10.1029/2026JB034259","DOIUrl":"https://doi.org/10.1029/2026JB034259","url":null,"abstract":"<p>The equivalent source method is widely used for processing and interpolating magnetic data, particularly in airborne surveys. However, implementations based on Cartesian coordinates present limitations at regional and global scales, where Earth curvature introduces geometric inconsistencies that affect data integration and modeling accuracy. To address this problem, this study proposes an adaptation of the magnetic equivalent source method to spherical coordinates, including revisions to its mathematical formulation to account for spherical geometry. The proposed framework enables consistent magnetic field modeling over large geographic areas. To improve the representation of magnetic sources, a dual-layer configuration is adopted to separate long- and short-wavelength components. Cross-validation is employed to determine optimal hyperparameters for each layer, ensuring stable and balanced inversions. To guarantee computational feasibility for large and high-resolution data sets, a gradient-boosting strategy is incorporated into the inversion process, significantly improving computational performance. Synthetic experiments demonstrate that the method remains stable and accurate for large-scale data sets, with tests conducted on synthetic data containing up to 500,000 observations and enables the reliable recovery of magnetic field components from total-field anomaly data. The approach was further applied to more than 1.5 million real observations, confirming its scalability and robustness. The recovered field amplitude provides additional constraints for data interpretation and enhances the geological analysis. The final implementation is released as open-source software to support reproducibility and broader adoption.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JB034259","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149146640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interseismic Strain Accumulation and Partitioning in Hispaniola From GNSS and InSAR","authors":"Christian Emmanuel,&nbsp;Eric Calais,&nbsp;Romain Jolivet,&nbsp;Bryan Raimbault,&nbsp;Steeve J. Symithe,&nbsp;Dominique Boisson","doi":"10.1029/2026JB034613","DOIUrl":"https://doi.org/10.1029/2026JB034613","url":null,"abstract":"<p>We combine GNSS and InSAR observations to constrain the spatial distribution of strain across the northeastern Caribbean plate boundary, focusing on Hispaniola, to investigate strain partitioning and fault slip rates in an actively deforming tectonic setting with significant seismic hazard. Including InSAR data substantially mitigates the effects of the sparse and uneven spatial distribution of GNSS stations that limited earlier models. We propose a new kinematic model that allows for internal deformation within selected tectonic blocks. While our results are broadly consistent with previous studies, we quantify the amount of compressional deformation within the Gulf of Gonâve, consistent with independent offshore observations, which likely materialize the eastern boundary of the Gonâve microplate. We assess the impact of spatially correlated noise in the InSAR measurements, which is especially significant in this tropical, topographically complex region, where atmospheric artifacts can obscure tectonic signals. We estimate surface strain rates and their associated uncertainties and compare these results with the geometry of faults imposed in block models. Our results confirm localized strain on the Enriquillo–Plantain Garden Fault at rates consistent with previous studies, with along–strike variations in fault geometry. In contrast, deformation in the northern Dominican Republic does not localize on the mapped trace of the Septentrional Fault but involves a broader area, in particular to the south of the main fault trace. The Septentrional Fault Zone and its subsidiary fault splays should all be considered capable of producing large earthquakes.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JB034613","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149047855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconciling Coupled Thermal-Water Evolution Models of Earth With Observations Through Variable Regassing Efficiency","authors":"Alexander B. Thames,&nbsp;Bradford J. Foley","doi":"10.1029/2025JB033701","DOIUrl":"https://doi.org/10.1029/2025JB033701","url":null,"abstract":"<p>Reconciling Earth's thermal evolution with geochemical observations remains a fundamental challenge, as parameterized convection models typically predict high present-day Urey ratios inconsistent with geochemical estimates. Previous studies propose that if mantle water concentration varies inversely to mantle temperature, it would weaken the feedback between temperature, viscosity, and heat loss, promoting primordial heat retention allowing models to match Urey ratio estimates. However, many previous coupled thermal-water models fail to produce such a water history, leading to Urey ratios that are still too high. We propose that a time-variable regassing efficiency provides a physical mechanism to resolve these discrepancies. We incorporate time-dependent regassing efficiency into parameterized coupled thermal-water models and produce realizations matching present-day constraints on critical mantle variables like mantle temperature, water concentration, and the Urey ratio while aligning with petrological estimates of Archean-Proterozoic mantle temperatures and Phanerozoic freeboard constancy. Variable regassing efficiency allows mantle water concentration to vary inversely with temperature by 1-2 orders of magnitude, drying as the mantle warms in the Archean then rehydrating as the mantle cools; such a scenario keeps viscosity approximately constant and weakens the feedback between mantle temperature and heat loss. Across &gt;95% of successful realizations Earth's total water budget is constrained to 1.25–1.7 ocean masses, with a maximum past surface water mass of ∼1.4 ocean masses. Low total water budgets permit sufficient Archean upper mantle dehydration while still allowing subsequent rehydration to remove excess surface water and match the present day ocean mass.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JB033701","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148994381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Persistent-Homology-Based Descriptors of Pore Heterogeneity for Generalized Permeability Prediction","authors":"Jingrui Liu,&nbsp;Fei Jiang,&nbsp;Arata Kioka,&nbsp;Wuquan Li,&nbsp;Yunfeng Liang,&nbsp;Shibo Xu,&nbsp;Takeshi Tsuji","doi":"10.1029/2026JB035021","DOIUrl":"https://doi.org/10.1029/2026JB035021","url":null,"abstract":"<p>Characterizing pore-structure heterogeneity is essential for understanding and predicting fluid transport processes in geological formations. However, it remains challenging because conventional descriptors capture only partial structural information, making it difficult to consistently distinguish complex pore structures across lithologies and scales. Here, we present a framework based on persistent homology (PH) to systematically characterize pore-structure heterogeneity in 3D digital rocks. By coupling pore network models with Dijkstra's algorithm, we first extracted functional connectivity-weighted pore nodes, thereby identifying the critical nodes that govern fluid transport. We then performed PH filtration on the sphere cloud representations of these pore nodes and analyzed the resulting persistence diagrams to extract topological characteristics. Accordingly, three dimensionless heterogeneity descriptors were introduced: birth multiscalarity (<i>I</i>_sp,b), persistence level (<i>I</i>_lv,p), and persistence multiscalarity (<i>I</i>_cv,p), which quantify the critical-scale heterogeneity, overall regional scale, and regional-scale heterogeneity of the transport network. In addition, we formulated a predictive model for the topological term in the Kozeny-Carman equation using selected descriptors, enabling permeability prediction across diverse sandstones and carbonates at varying scales. Overall, this study demonstrates that PH-derived descriptors can comprehensively decouple distinct facets of structural heterogeneity, providing a physically interpretable framework that bridges structural signatures and transport responses.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JB035021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149146580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the Plumbing System Beneath Askja Caldera, Iceland, Revealed by Microgravity and Deformation Data During Uplift Between 2022 and 2023","authors":"Josefa Sepúlveda-Araya,&nbsp;Andrew Hooper,&nbsp;Elske van Dalfsen,&nbsp;Susanna K. Ebmeier,&nbsp;Michelle Parks,&nbsp;Freysteinn Sigmundsson,&nbsp;Yilin Yang,&nbsp;Milan Lazecký,&nbsp;Mathijs Koymans,&nbsp;Chiara Lanzi,&nbsp;Pedro Espín-Bedón","doi":"10.1029/2025JB033402","DOIUrl":"https://doi.org/10.1029/2025JB033402","url":null,"abstract":"&lt;p&gt;In July 2021, an episode of uplift started at Askja caldera, Iceland, following over 50 years of subsidence. The initial inflation rate was approximately &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;700&lt;/mn&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mi&gt;m&lt;/mi&gt;\u0000 &lt;mi&gt;m&lt;/mi&gt;\u0000 &lt;mo&gt;/&lt;/mo&gt;\u0000 &lt;mi&gt;y&lt;/mi&gt;\u0000 &lt;mi&gt;r&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $700hspace*{.5em}mathrm{m}mathrm{m}/mathrm{y}mathrm{r}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, declining to &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;350&lt;/mn&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mi&gt;m&lt;/mi&gt;\u0000 &lt;mi&gt;m&lt;/mi&gt;\u0000 &lt;mo&gt;/&lt;/mo&gt;\u0000 &lt;mi&gt;y&lt;/mi&gt;\u0000 &lt;mi&gt;r&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $350hspace*{.5em}mathrm{m}mathrm{m}/mathrm{y}mathrm{r}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; within 1 month. This deformation has been attributed to a magma intrusion into a pre-existing body of mush. To investigate the physical properties of both the intruded magma and the sub-volcanic mush zone, we jointly inverted GNSS and InSAR ground deformation observations, along with microgravity data from 2022 to 2023 surveys, employing a pressurized, inflating ellipsoid embedded in an elastic half space. Our results indicate a mass increase of &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;8.14&lt;/mn&gt;\u0000 &lt;mo&gt;×&lt;/mo&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;msup&gt;\u0000 &lt;mn&gt;0&lt;/mn&gt;\u0000 &lt;mn&gt;10&lt;/mn&gt;\u0000 &lt;/msup&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mi&gt;k&lt;/mi&gt;\u0000 &lt;mi&gt;g&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $8.14times 1{0}^{10}hspace*{.5em}mathrm{k}mathrm{g}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; (95&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;%&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $%$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; confidence interval (7.01–9.22) &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;×&lt;/mo&gt;\u0000 &lt;mn&gt;1&lt;/mn&gt;\u0000 &lt;msup&gt;\u0000 &lt;mn&gt;0&lt;/mn&gt;\u0000 &lt;mn&gt;10&lt;/mn&gt;\u0000 &lt;/msup&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mi&gt;k&lt;/mi&gt;\u0000 &lt;mi&gt;g&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${times} 1{0}^{10}hspace*{.5em}mathrm{k}mathrm{g}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) and a mean pressure change of 2.67 MPa in a volume that extends from ∼0.4–4.6 km below surface, which we interpret ","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JB033402","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148994130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermo-Mechanical Controls on Central-Vent Caldera Collapse","authors":"Pascal S. Aellig,&nbsp;Albert de Montserrat,&nbsp;Boris J. P. Kaus","doi":"10.1029/2026JB034434","DOIUrl":"https://doi.org/10.1029/2026JB034434","url":null,"abstract":"<p>Large-scale magmatic systems are associated with catastrophic caldera-forming eruptions, posing hazards to millions near active volcanoes. Despite occurring across a range of sizes, the physics driving caldera collapse remain incompletely understood. While large calderas have received considerable attention, moderately sized calderas (∼5–10 km), such as Crater Lake (USA), attributed to central-vent eruptions with volumes of 10–100 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mtext>km</mtext>\u0000 <mn>3</mn>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${text{km}}^{3}$</annotation>\u0000 </semantics></math>, remain comparatively understudied. We therefore developed a multi-physics numerical modeling approach to investigate the mechanics of such collapses using the thermo-mechanical code JustRelax.jl. Our 2D models couple magma dynamics, far-field tectonic stresses, and non-linear visco-elasto-viscoplastic rheologies for the crust and magma. Each model incorporates a thermally active, convecting magma chamber and surrounding mush, a volcanic edifice, melting and solidification of host rock, and a parametrization for magma recharge and eruption. Results show two distinct types of ring fault development: outward-to-subvertical faults nucleating at the surface and propagating downward, and radial faults originating at the chamber roof and propagating upward, with a transitional regime capable of evolving toward either type. Collapse dynamics range from structured, piston-like subsidence to chaotic, non-coherent roof block collapse. We find that the underpressure required for collapse onset scales logarithmically with the roof ratio and provide a scaling law that captures this behavior. Thermal weakening of the crust has a significant effect on eruption potential, shifting systems from a mass-injection-dominated to a non-eruptive regime. Applied to natural calderas, our models reproduce key observational constraints including caldera diameter and erupted volumes, providing a novel thermo-mechanical framework for understanding central-vent caldera collapse.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JB034434","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148993939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crustal Anisotropy and Deformation Mechanism of the Southern South China Block","authors":"Huiyu Tian,&nbsp;Jianshe Lei,&nbsp;Dapeng Zhao,&nbsp;Longchun Qian","doi":"10.1029/2026JB033894","DOIUrl":"https://doi.org/10.1029/2026JB033894","url":null,"abstract":"<p>The South China block (SCB) has a complex history of tectonic evolution. To gain comprehensive insights into the driving mechanism and causes of crustal deformation in the region, we investigate crustal anisotropy by applying the receiver-function method based on Pms splitting to teleseismic waveforms recorded at 250 broadband seismic stations, including 162 HAVESArray portable stations and 88 provincial permanent stations. Reliable anisotropy results are obtained at 216 stations. Our results show that the overall fast axis orientation (FAO) in the southern SCB is WNW-ESE, but distinct FAO patterns are observed across different tectonic regions. In the eastern Cathaysian block, the FAO is NW-SE, aligning with the strike of fault zones in some tectonic areas, whereas the FAO is perpendicular to the fault strike in other areas. This feature may be associated with tectonic extension induced by the Paleo-Pacific plate subduction. In the Leizhou peninsula, the FAO transitions from NW-SE in the north to WNW-ESE in the south, potentially recording traces of crustal deformation caused by horizontal flow of the Hainan mantle plume. In the western Cathaysian block, the dominant FAOs are NW-SE and NE-SW, likely associated with the presence of a series of NW- and NE-trending conjugate fault zones in the region, as well as the Indian plate subduction. In Hainan Island, the FAO is mainly E-W, which may reflect the influence of E-W striking faults, such as the Wangwu-Wenjiao fault, the Jianfeng-Diaoluo fault, and the Jiusuo-Lingshui fault.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"131 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148943357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}