Journal of Geophysical Research: Solid Earth最新文献

{"title":"Regimes of Element Transfer Between Earth's Core and Basal Magma Ocean","authors":"Zhongtian Zhang,&nbsp;Haiyang Luo,&nbsp;Ming Hao,&nbsp;Jie Deng","doi":"10.1029/2025JB031357","DOIUrl":"https://doi.org/10.1029/2025JB031357","url":null,"abstract":"<p>Earth's accretion was highly energetic and likely involved multiple global melting events. Following the Moon-forming giant impact, extensive mantle melting and the separation of solids and melts under deep mantle pressures likely produced a basal magma ocean (BMO) beneath the solidified mantle. The presence and evolution of the BMO have been proposed to explain key geophysical and geochemical features of the lowermost mantle. Understanding the evolution of the BMO is crucial for testing these hypotheses, but its interaction with the core presents a significant challenge, as the mechanism of this exchange remains unclear. In this study, we develop a theoretical framework to assess the regime of BMO-core exchange based on the compositions of the BMO and the core. We propose that during solidification, the BMO may evolve into a regime where the reaction at the BMO-core interface drives compositional convection in liquids on both sides, if the core has a high enough Si content (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>≳</mo>\u0000 <mn>4</mn>\u0000 </mrow>\u0000 <annotation> $gtrsim 4$</annotation>\u0000 </semantics></math>–<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>7</mn>\u0000 <mspace></mspace>\u0000 <mi>w</mi>\u0000 <mi>t</mi>\u0000 <mi>%</mi>\u0000 </mrow>\u0000 <annotation> $7 mathrm{w}mathrm{t}mathrm{%}$</annotation>\u0000 </semantics></math>, under the assumption that the O content is <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 <mn>1.5</mn>\u0000 </mrow>\u0000 <annotation> ${sim} 1.5$</annotation>\u0000 </semantics></math>–<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>3</mn>\u0000 <mspace></mspace>\u0000 <mi>w</mi>\u0000 <mi>t</mi>\u0000 <mi>%</mi>\u0000 </mrow>\u0000 <annotation> $3 mathrm{w}mathrm{t}mathrm{%}$</annotation>\u0000 </semantics></math>). In this scenario, the BMO-core exchange would be much more efficient than previously estimated, buffering the tendency of FeO enrichment during crystallization and shortening the lifetime of the BMO.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144673177","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":"Low-Degree Spherical Harmonic Coefficients for GRACE/GRACE-FO Gravity Field Models From the Fingerprint Approach","authors":"Changlin Mei,&nbsp;Yu Sun,&nbsp;Yang Li","doi":"10.1029/2024JB029792","DOIUrl":"https://doi.org/10.1029/2024JB029792","url":null,"abstract":"<p>Low-degree coefficients of time-variable gravity field models from Gravity Recovery and Climate Experiment (GRACE) and GRACE-Follow On (GRACE-FO) capture large-scale mass changes within the Earth system. However, some of these coefficients are either missing (e.g., degree-1 coefficients) or poorly determined (e.g., <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mrow>\u0000 <msub>\u0000 <mi>C</mi>\u0000 <mn>20</mn>\u0000 </msub>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> ${C}_{20}$</annotation>\u0000 </semantics></math>). Such a situation is exacerbated particularly over the GRACE-FO period when one of the accelerometers carries elevated noise. In this study, we present a framework for estimating low-degree coefficients using the fingerprint approach. Our results demonstrate that this method can reliably estimate multiple coefficients simultaneously, producing degree-1, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mrow>\u0000 <msub>\u0000 <mi>C</mi>\u0000 <mn>20</mn>\u0000 </msub>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> ${C}_{20}$</annotation>\u0000 </semantics></math>, and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mrow>\u0000 <msub>\u0000 <mi>C</mi>\u0000 <mn>30</mn>\u0000 </msub>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> ${C}_{30}$</annotation>\u0000 </semantics></math> estimates that are comparable to the currently recommended solutions, both in direct comparisons and in the context of estimating mass changes over the Antarctic Ice Sheet. This framework not only provides an alternative approach for determining low-degree coefficients currently identified as problematic in GRACE/GRACE-FO gravity field models, but also shows potential for addressing other degraded low-degree coefficients that may emerge during future GRACE-FO operations.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144666405","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 Possible Late Jurassic Final Closure of the Mongol-Okhotsk Ocean in Its Eastern Segment: Constraints From New Paleomagnetic Investigations","authors":"Pan Zhao,&nbsp;Yifei Hou,&nbsp;Zhenhua Jia,&nbsp;Erwin Appel,&nbsp;Chenglong Deng,&nbsp;Yan Chen","doi":"10.1029/2024JB030741","DOIUrl":"https://doi.org/10.1029/2024JB030741","url":null,"abstract":"<p>Closure of the Mongol-Okhotsk Ocean (MOO) marks the final continental configuration of central Asia. Here we present a paleomagnetic study on the Upper Jurassic sedimentary rocks from the northern part of the Amuria Block (AMB) in northeastern China that is directly south of the Mongol-Okhotsk suture to constrain the timing of its final closure in the eastern segment. Rock magnetic experiments reveal that magnetite and hematite are magnetic carriers of the characteristic remanent magnetization. Site-mean directions isolated from 21 sites show antipodal normal and reversed polarities, passing both fold and reversal tests. After applying Elongation/Inclination correction of inclination shallowing, an age-mean direction is calculated at <i>D</i>_s/<i>I</i>_s = 196.7°/−68.2° (<i>k</i> = 71.9, <i>α</i>_95s = 1.3°) in stratigraphic coordinates, corresponding to a Late Jurassic paleomagnetic pole of <i>λ</i>/<i>φ</i> = 78.3°N/184.6°E (<i>A</i>₉₅ = 2.0°) for the AMB. Combining paleomagnetic data with regional geological evidence, we propose a possible Late Jurassic closure of the MOO in its eastern segment, marking the final closure of the MOO and the formation of the central Asian continent.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144666435","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":"Assessing the Reliability of the Pseudo-Thellier Estimates in Fired Ceramics and Source Clays","authors":"Wilbor Poletti,&nbsp;Mikaelly G. Rocha,&nbsp;Plínio Jaqueto,&nbsp;Gelvam A. Hartmann,&nbsp;Grasiane L. Mathias,&nbsp;Daniele Brandt,&nbsp;Ricardo I. F. Trindade,&nbsp;Paulo Maximiano","doi":"10.1029/2025JB031980","DOIUrl":"https://doi.org/10.1029/2025JB031980","url":null,"abstract":"<p>The geomagnetic field's intensity is key to understanding the Earth's core dynamics and their surface impacts. While the Thellier–Thellier method remains the standard for recovering absolute paleointensity from baked materials, it is time-consuming and may alter magnetic mineralogy due to heating cycles. The pseudo-Thellier method offers a non-thermal, faster alternative based on coercivity spectra, but its application to thermally magnetized ceramics remains unexplored. It is important to highlight that using the pseudo-Thellier method to retrieve absolute intensity requires calibration of relative data. Here, we assess the reliability of pseudo-Thellier method using ceramics and decanted clay from modern production sites in Turmalina (MG) and Cunha (SP), southeastern Brazil. Relative paleointensity estimates were compared with known intensity field values and analyzed in relation to magnetic mineralogical properties. Five samples passed all selection criteria and yielded a mean calibration factor of 2.20 ± 0.59, consistent with values obtained for volcanic rocks. Our results show: (a) Relative paleointensity reliability depends on combined statistical criteria (i.e., NRM fraction, MAD, linearity and curvature of adjustments, and pseudo-checks); (b) pseudo-Arai analysis alone (visual or statistical) are insufficient for a robust paleointensity estimation; (c) high-coercivity components may result to unreliable intensities, therefore an S-ratio &gt; 0.90 is suggested to pre-select samples; (d) remanence anisotropy significantly affects pseudo-Thellier estimates and must be corrected using ARM anisotropy tensor, with a recommended maximum anisotropy tolerance of 25% (0.75 &lt; <i>f</i>_ani &lt; 1.25). We propose here that the pseudo-Thellier method must be systematically incorporated into archeointensity studies, even though as a complementary approach, to improve data reliability and strengthen methodological frameworks.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JB031980","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144663778","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":"Unified Theory of Elastic Nonlinearity for Stress-Dependent Wave Propagation in Porous and Fractured Rocks With Weakly Cemented Contacts","authors":"Bo-Ye Fu,&nbsp;Li-Yun Fu","doi":"10.1029/2025JB031745","DOIUrl":"https://doi.org/10.1029/2025JB031745","url":null,"abstract":"<p>Mechanical deformations of porous and fractured rocks with weak intergranular cementation involve significantly different varieties of nonlinear stress–strain behaviors due to the presence of compliant microstructures such as cracks and grain contacts, generally including nonlinear elastic (due to crack closure and intergranular compaction), hyperelastic (due to stress accumulation), and inelastic (due to crack growth) deformations prior to mechanical failure. Various piecewise modeling approaches have been proposed to describe stress-dependent wave propagation by focusing on certain elastic behavior. However, these highly differentiated mechanical deformations are not exclusive mutually but coexist with different levels of contributions in different stress segments during the progressive deformation process. We address this issue by integrating these diverse-source elastic nonlinearities into a coupled framework where the total energy function consists of hyperelastic strains in the background (grains and stiff pores) and nonlinear strains by intergranular compaction and crack closure. By assuming intergranular compaction to be the category of nonlinear elasticity, we propose a penny-shaped, cement-filled crack to approximate the mechanical behavior of intergranular contact structures, facilitating the construction of strain energy functions for intergranular compaction. We investigate the effects of stiff and compliant pores, contact structures area, and coordination numbers on the effective elastic moduli. Applications to experimental data with Fontainebleau (porosity 4%), Vosges (porosity 25%), and Bleurswiller (porosity 25%) sandstones show that predicted wave velocities agree well with ultrasonic measurements at different effective stresses.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144663768","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":"State of Stress Across Major Faults in the Nankai Subduction Zone Estimated From Wellbore Breakouts","authors":"Kaitlin E. Schaible,&nbsp;Demian M. Saffer","doi":"10.1029/2024JB030242","DOIUrl":"https://doi.org/10.1029/2024JB030242","url":null,"abstract":"<p>Quantifying the orientation and magnitude of stress at tectonically active margins and along major fault systems is integral to understanding the mechanics of faulting and earthquakes. Here we use data collected as part of the IODP (Integrated Ocean Drilling Program) Nankai Trough Seismogenic Zone Experiment to constrain in situ stress magnitudes within the Nankai accretionary prism from wellbore breakouts. During drilling, stresses are concentrated around the borehole wall and result in compressional failure in the form of breakouts. We place bounds on the minimum (<i>S</i>_hmin) and maximum (<i>S</i>_Hmax) horizontal stresses using a combination of breakout widths, together with estimates of rock strength derived from p-wave velocity. Our analysis focuses on two regions: (a) a major out of sequence thrust fault located ∼25 km landward of the trench, termed the megasplay (Sites C0004, C0010, and C0022), and (b) the décollement within a few kilometers of the trench (Sites C0006 and C0024). We find that the stress state along the megasplay lies in a thrusting regime (<i>S</i>_Hmax &gt; <i>S</i>_hmin &gt; <i>S</i>_<i>v</i>) with shear stresses consistent with slip on the fault, whereas at the toe of the prism stress state is near-isotropic, with small differential stresses. Our results suggest that the megasplay fault is near failure. In contrast, the décollement near the trench is far from failure, likely requiring a combination of a frictionally weak plate boundary and progressive interseismic loading that drives increasing horizontal stress over time.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144663779","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":"Dynamics of Fluid-Driven Slip on a 3D Heterogeneous Fault With Rate-and-State Friction","authors":"Navid Hosseini,&nbsp;Adriana Paluszny,&nbsp;Robert W. Zimmerman","doi":"10.1029/2025JB031221","DOIUrl":"https://doi.org/10.1029/2025JB031221","url":null,"abstract":"<p>A three-dimensional quasi-dynamic finite element approach is presented for the simulation of fluid-driven seismicity on a heterogeneous fault with rate-and-state friction. The coupled nonlinear hydro-mechanical equations of the fault and surrounding matrix are solved monolithically, using the Imperial College Geomechanics Toolkit, to obtain the fluid pressure and displacement fields. This study solves for friction on the fault surfaces, wherein the augmented Lagrangian method is used to apply the contact constraints in a finite element framework. A stick-predictor slip-corrector algorithm is developed for the rate-and-state friction law to obtain better convergence. It is found that the spatial mesh size and temporal time step must meet specific criteria in order to guarantee the convergence of an iterative solver. The fault is represented as a surface in the model using zero-thickness interface elements. The heterogeneous fault has velocity-weakening asperities, surrounded by creeping velocity-strengthening barriers. Changes in pore pressure trigger an aseismic slip front propagating along the creeping barriers, leading to the failure of asperities. The characteristics of fluid-induced aseismic slip are described, along with its interaction with seismogenic asperities. Numerical results show that the seismicity of a heterogeneous fault can be determined using a geometry-material diagram based on two measurable fault parameters: the ratio <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mrow>\u0000 <mi>a</mi>\u0000 <mo>/</mo>\u0000 <mi>b</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $a/b$</annotation>\u0000 </semantics></math> of the frictional parameters of the creeping region, and the areal density of the velocity-weakening asperities. It is shown that these two parameters can control the post-seismic distribution of slippage around each asperity, which can be a trigger for secondary seismic events on neighboring asperities.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JB031221","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144657688","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":"Revised Oceanic Plate Cooling Models","authors":"M. C. Holdt,&nbsp;N. J. White,&nbsp;F. D. Richards","doi":"10.1029/2024JB029890","DOIUrl":"https://doi.org/10.1029/2024JB029890","url":null,"abstract":"<p>Global age-depth and heat flow observations provide constraints for cooling and subsidence of oceanic plates. Numerous studies have addressed this problem, which has a bearing upon the calibration of shear-wave tomographic models and upon lithospheric rheology. The robustness of these results depends upon the quality and spatial distribution of both age-depth and heat flow measurements. Here, we revisit the plate cooling model for two reasons. First, a database of 10,863 age-depth measurements that are distributed throughout the oceanic realm has been constructed. This database is combined with 3,573 heat flow measurements. Second, we wish to explore a range of analytical and numerical plate models that incorporate the temperature- and pressure-dependence of conductivity, of expansivity, and of specific heat capacity. Our goal is to identify plate models that jointly fit observational constraints, whilst honoring laboratory-based estimates of key thermal parameters. Both simple analytical and comprehensive numerical parameterizations recover an equilibrium plate thickness of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>105</mn>\u0000 <mo>±</mo>\u0000 <mn>10</mn>\u0000 </mrow>\u0000 <annotation> $105pm 10$</annotation>\u0000 </semantics></math> or <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>96</mn>\u0000 <mo>±</mo>\u0000 <mn>10</mn>\u0000 </mrow>\u0000 <annotation> $96pm 10$</annotation>\u0000 </semantics></math> km with a temperature of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>1</mn>\u0000 <mo>,</mo>\u0000 <mn>326</mn>\u0000 <mo>±</mo>\u0000 <mn>50</mn>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <annotation> $1,326pm 50{}^{circ}$</annotation>\u0000 </semantics></math>C. This recovered temperature is consistent with independent petrologic constraints. Spatial analysis of age-depth measurements demonstrates that previously invoked transient plate shallowing is not globally observed. This observation implies that the possible onset of a convective instability, which has been proposed as a mechanism to stabilize equilibrium plate thickness, might act on shorter length scales than that implied by previously reported transient shallowing. Finally, our revised plate model is used to track lithospheric thermal structure as a function of time and to calculate residual depth anomalies.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB029890","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647111","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":"Insights Into Seismicity Associated With Flexibly Operating Enhanced Geothermal System From Real-Time Distributed Acoustic Sensing","authors":"Michal Chamarczuk,&nbsp;Jonathan Ajo-Franklin,&nbsp;Avinash Nayak,&nbsp;Jack Norbeck,&nbsp;Tim Latimer,&nbsp;Aleksei Titov,&nbsp;Sireesh Dadi","doi":"10.1029/2025JB031634","DOIUrl":"https://doi.org/10.1029/2025JB031634","url":null,"abstract":"<p>Enhanced Geothermal Systems (EGS) have the capacity to broaden the accessible resource pool for geothermal power generation. Traditionally viewed as a “baseload” resource, their flexible operation might also enable dispatchable load-following generation and long-term energy storage, aligning them with the evolving landscape of decarbonized electricity systems. However, increasing permeability and extracting energy during EGS operations can induce microseismic events; for many prior EGS efforts, some associated seismicity has been observed. While energetically beneficial, the flexibility of EGS operations prompts our inquiry into whether new types of operations will yield previously unseen seismicity patterns. We demonstrate the use of distributed acoustic sensing (DAS) with real-time edge computing to monitor seismicity during a pilot test of a cyclically operated EGS facility at the Blue Mountain geothermal field. Our focus lies in uncovering seismicity insights from the real-time microseismic catalog, particularly during load-following dispatchability tests simulating flexible EGS operation. We find that variations in pore pressure consistently correlate with seismicity, and that controlling pressure cycles during flexible operations appears to constrain microseismic activity during subsequent cycles. The spatio-temporal evolution of microseismic clouds recorded during cyclic injection cycles fits diffusive models over our available observation period. Additionally, seismicity elevation lags behind pore pressure increases, likely due to pressure diffusion to the fracture system boundary. Through real-time monitoring, we offer novel insights into seismicity associated with flexibly operating EGS. Our findings suggest that leveraging DAS and edge computing can inform EGS operations and help mitigate induced seismicity.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647110","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":"Hydrodynamics of Fault Gouges From Constitutive Modelling to the Physics of Friction","authors":"Filippo Masi,&nbsp;Itai Einav","doi":"10.1029/2024JB030822","DOIUrl":"https://doi.org/10.1029/2024JB030822","url":null,"abstract":"<p>The development of rate- and state-dependent friction laws offered important insights into the key physical mechanisms of the frictional behavior of fault gouges and their seismic cycle. However, past approaches were specifically tailored to address the problem of fault shearing, leaving questions about their ability to comprehensively represent the gouge material under general loading conditions. This work establishes an alternative approach for developing a physical friction law for fault gouges that is grounded on the rigour of the hydrodynamic procedure with two-scale temperatures through <i>Terracotta</i>, a thoroughly robust constitutive model for clay in triaxial loading conditions. By specifying the model for direct shearing, the approach yields an alternative friction law that readily captures the frictional dynamics of fault gouges, including explicit dependencies on gouge layer thickness, normal stress, and solid fraction. Validated against available laboratory experiments, the friction law retains the original predictive capabilities of Terracotta in triaxial conditions and explains the rate-and-state, dilatational behavior of fault gouges in direct shear conditions. Finally, when the Terracotta friction law is connected to a spring-dashpot representation of the host rock, the combined model predicts an elastic buildup precursor to the onset of and subsequent seismicity, with results closely reflecting experimental evidence and field observations. While this study focuses on clay-rich gouges, the approach and findings are expected to offer much wider implications to a variety of materials.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030822","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144647112","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}