Journal of Geophysical Research: Solid Earth最新文献

{"title":"Toward a Refined Estimation of Geocenter Motion From GNSS Displacements: Mitigating Thermoelastic Deformation and Systematic Errors","authors":"Na Wei,&nbsp;Yuxin Zhou,&nbsp;Chuang Shi,&nbsp;Xueqing Xu,&nbsp;Paul Rebischung,&nbsp;Jingnan Liu","doi":"10.1029/2024JB028967","DOIUrl":"https://doi.org/10.1029/2024JB028967","url":null,"abstract":"<p>The geocenter motion (GCM), associated with the degree-1 component of surface mass redistribution in the Earth's fluid envelope, is difficult to observe with sufficient precision. Estimating GCM through the degree-1 deformation approach assumes that seasonal Global Navigation Satellite System (GNSS) variations are primarily induced by surface mass loading. However, this is not the case for GNSS displacements due to the presence of prominent non-loading errors. For a refined estimation of GCM, we modeled and mitigated three types of non-loading errors, including bedrock thermoelastic deformation, GNSS draconitic errors (DRE), and background noises, in GNSS displacements derived from the International GNSS Service third reprocessing. Results demonstrate that thermoelastic deformation is a significant contributor to annual variations in the <i>Z</i> component with an amplitude of approximately 1.8 mm. Prominent non-seasonal scatters in the <i>X</i> and <i>Y</i> components are also significantly reduced by removing DRE and filtering out background noises. Besides, an abnormal fluctuation in the <i>X</i> component over the period 2012–2014 has also been mitigated. Overall, by accounting for non-loading errors, the GNSS-derived GCM becomes more consistent with independent GCM estimates from the geophysical loading model, the method combined Gravity Recovery and Climate Experiment and Ocean Bottom Pressure data, and Satellite Laser Ranging. Taking the geophysical loading model as an example, the percentages of GNSS-derived GCM variances that can be explained are remarkably improved from (35%, 60%, and 48%) to (75%, 68%, and 73%) in the <i>X</i>, <i>Y</i>, and <i>Z</i> components, respectively. Accurate modeling of non-loading errors can provide a perspective for obtaining refined geocenter estimates solely relying on GNSS displacements.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB028967","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144598268","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":"Petrological Constraints on Magma Ascent Processes During the 1977 Eruption of Usu Volcano, Japan","authors":"Shuhei Hotta,&nbsp;Satoshi Okumura,&nbsp;Kazuhisa Matsumoto,&nbsp;Tsuyoshi Miyamoto,&nbsp;Akihiko Tomiya,&nbsp;Kiyoaki Niida","doi":"10.1029/2024JB030966","DOIUrl":"https://doi.org/10.1029/2024JB030966","url":null,"abstract":"<p>Sub-Plinian eruptions often repeat at short intervals, and the magma discharge rate during these eruptions changes. The mechanism that controls the variation in discharge rate remains unclear; however, its understanding is essential for predicting the evolution of explosive eruptions and mitigating disasters. Here, we used petrological methods to investigate the magma ascent processes during the 1977 eruption of Usu volcano, which included four sub-Plinian eruptions and two relatively small pumice-rich eruptions. The water content of the melt inclusions in the first sub-Plinian eruption indicated a pressure of 100–125 MPa under the assumption of water saturation. From the second to fourth sub-Plinian eruptions, the minimum water content gradually decreased. The crystal size distributions of plagioclase microlites in the groundmass show large variations in small size (&lt;1 μm), and these small crystals are inferred to crystallize at low pressure (&lt;40 MPa), confirmed by decompression-induced crystallization experiments. Based on these observations, we inferred the following scenario: the magma in the first sub-Plinian eruption ascended from the magma reservoir at a depth of ∼4 km; however, the magma stagnated in a shallow conduit and then ascended to the surface during the second to fourth sub-Plinian eruptions. Moreover, the position of the magma head in the conduit gradually became shallower. The results of this study indicate that the evolution of explosive eruptions during the 1977 eruption of Usu volcano originated from the processes and conditions of both the magma reservoir and the shallow parts of the conduit.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030966","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144606615","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":"Imaging the Sediment Cover Offshore Central Chile With Surface-Wave Dispersion and P-Wave Conversion Using Distributed Acoustic Sensing","authors":"Clara Vernet,&nbsp;Alister Trabattoni,&nbsp;Marie Baillet,&nbsp;Martijn van den Ende,&nbsp;Diane Rivet","doi":"10.1029/2024JB030507","DOIUrl":"https://doi.org/10.1029/2024JB030507","url":null,"abstract":"<p>Distributed acoustic sensing (DAS) is an attractive solution for ocean-bottom seismological instrumentation, providing dense and long-range measurements of ground deformation along submarine fiber optic cables. By sensing a 145 km telecom cable in central Chile, we determined the sedimentary cover structure leveraging both surface wave dispersion and the time difference of arrival (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Δ</mi>\u0000 <mi>t</mi>\u0000 </mrow>\u0000 <annotation> ${Delta }t$</annotation>\u0000 </semantics></math>) between the transmitted P and converted S waves from the bedrock-sediment interface. We estimated the shear wave velocity (Vs) profile and sediment thickness by performing a joint inversion of Scholte-wave dispersion curves and <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Δ</mi>\u0000 <mi>t</mi>\u0000 </mrow>\u0000 <annotation> ${Delta }t$</annotation>\u0000 </semantics></math> along the fiber. The dispersion curves were extracted from the seismic coda of local and regional earthquakes using frequency-wavenumber analysis. The additional information provided by the observed <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Δ</mi>\u0000 <mi>t</mi>\u0000 </mrow>\u0000 <annotation> ${Delta }t$</annotation>\u0000 </semantics></math> improved depth inversion constraints, enhancing the stability of the retrieved sedimentary cover thickness. Our results show significant variations in thickness and Vs along the cable, providing new insights into the structure of sedimentary deposits along the margin. The influence of tectonic structures, such as faults and basins, is reflected in the observed velocity contrasts and sediment accumulation patterns. Southern structures, such as the Valparaiso Forearc Basin and canyons, are not characterized by significant sedimentary deposits (&lt;500 m.s⁻¹). Beyond the Punta Salinas Ridge, the sediment velocity increases slightly while crossing basin-like features. The proposed methodology, combining surface waves dispersion and P-to-S conversion, confirms the effectiveness of DAS for high-resolution subsurface imaging. These results highlight the importance of accounting for spatial variability in sedimentary velocity when modeling seismic hazards and tectonic dynamics in subduction zones.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030507","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144598390","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":"Strong Fault Interaction in Double-Vergence Structure: Lessons From the 2022 Yuli Earthquake and the 2022 Chihshang Earthquake, Eastern Taiwan","authors":"Yuri Ishimaru,&nbsp;Youichiro Takada,&nbsp;Kuo-En Ching,&nbsp;Wu-Lung Chang","doi":"10.1029/2025JB031225","DOIUrl":"https://doi.org/10.1029/2025JB031225","url":null,"abstract":"<p>The Longitudinal Valley Fault (LVF) and the Central Range Fault (CRF) in eastern Taiwan consist of a head-to-head double-vergence structure hosting disastrous earthquakes. It was previously proposed that the fault slip on one of these faults suppresses the earthquake generation on the other. Nonetheless, the 2022 Chihshang earthquake (<i>M</i>_<i>w</i> 7.0) on the CRF occurred soon after the 2022 Yuli earthquake (<i>M</i>_<i>w</i> 6.7) on the LVF. Here, we provide a comprehensive framework of the fault interaction consistently explaining these contradictory findings. First, we estimated the coseismic slip distribution of the Yuli earthquake from Global Navigation Satellite System (GNSS) and L-band satellite interferograms. The results indicate almost pure reverse faulting. Second, with the estimated slip distribution, we calculated changes in Coulomb failure function (ΔCFF) on the CRF due to the Yuli earthquake on the LVF. The ΔCFF reaches +0.25 MPa around the main rupture area of the Chihshang earthquake, which is equivalent to the clock advance of 36–100 years, suggesting a large impact on the earthquake generation cycles. Finally, we found that a rake angle of fault slip has a significant effect on the ΔCFF on the other fault in the double-vergence structure: it takes large positive values when 90° like the Yuli earthquake, but almost negative when 45° or less, which comprehensively explains the seismic quiescence previously reported and the positive ΔCFF on the CRF caused by the Yuli earthquake. The strong impact of the rake angle is also supported by the temporal distribution of historical earthquakes in eastern Taiwan.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JB031225","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144589629","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":"Characterizing Fractured Zones in Urban Karst Geology Using Leaky Surface Waves From Distributed Acoustic Sensing","authors":"Zhinong Wang,&nbsp;Tieyuan Zhu","doi":"10.1029/2025JB031477","DOIUrl":"https://doi.org/10.1029/2025JB031477","url":null,"abstract":"<p>Urban karst geology poses significant geohazard risks, most notably sinkholes and surface depression stemming from soluble and fractured bedrock that is prone to dissolution and collapse. However, mapping and characterizing these hazards using traditional geophysical surveys in cities is challenging due to dense infrastructure and high levels of human activity. In this work, we demonstrate how distributed acoustic sensing (DAS), deployed via preexisting telecommunication fiber-optic cables, can be leveraged to detect fractured weak zones in a populated setting. By recording traffic noises, we are able to conduct large-scale, cost-effective, and minimally intrusive subsurface investigations. Our workflow integrates ambient noise interferometry with advanced signal enhancement techniques, specifically frequency-wavenumber (F-K) filtering and bin-offset stacking. F-K filtering isolates wavefields traveling in opposite directions to suppress localized noise, while bin-offset stacking further enhances signal coherency by superposing channels with common offsets. The resulting Noise Cross-correlation Functions exhibit unique inverse-dispersion patterns that signify the presence of leaky surface waves generated by a low-velocity half-space. We invert the corresponding dispersion curves to derive a 2D S-wave velocity model, highlighting a prominent low-velocity anomaly indicative of a fractured zone. To confirm the karstic nature of this anomaly, rock physics modeling is employed to estimate spatial variations in fracture density, revealing marked heterogeneity in the fractured zone. Our findings underscore the power of DAS-based ambient noise interferometry for delineating karst features and diagnosing potential sinkhole risks in urban environments. By exploiting widely available fiber-optic networks, this approach significantly broadens the practicality of near-surface geohazard mapping at the city scale.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JB031477","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144582135","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":"Magmatic System of the Hainan Plume Revealed by Ambient Noise Tomography","authors":"Gong Deng,&nbsp;Jianshe Lei,&nbsp;Dapeng Zhao,&nbsp;Rui Gao","doi":"10.1029/2024JB030696","DOIUrl":"https://doi.org/10.1029/2024JB030696","url":null,"abstract":"<p>The magmatic system of the Hainan plume is important for unraveling the mechanism of intraplate volcanism. We develop a detailed three-dimensional shear-wave velocity (Vs) model of the crust and uppermost mantle using ambient noise tomography to investigate the magmatic system of the Hainan plume. Rayleigh wave phase velocity dispersions (5–40 s) are extracted from seismograms recorded at 74 broadband stations, including 32 Chinese provincial network stations and 42 portable stations of the Hainan Active Volcano Experiment of Seismic Array (HAVESArray). The integration of the HAVESArray data substantially improves the spatial resolution of the new Vs model. Our results show that high-Vs zones mainly exist under southern Hainan Island and northern Leizhou peninsula, whereas low-Vs zones appear primarily beneath the Beibuwan basin and the Leiqiong volcanic field. Two distinct low-Vs zones are revealed beneath the Leiqiong volcanic field. The deeper zone exists at depths of 24–40 km and has a Vs reduction of ∼5%, whereas the shallower zone exists at depths of 12–20 km and has a Vs reduction of ∼8%. The two low-Vs zones are connected vertically. These results suggest that the interconnected deep and shallow magma reservoirs may regulate the magma supply between the volcanic field and the Hainan mantle plume. Furthermore, seismic swarms in the Qiongshan area are predominantly located along the boundaries between high-Vs and low-Vs anomalies. We infer that the 1605 <i>M</i>7.5 Qiongshan earthquake was likely caused by the disruption of the overlying brittle crustal seal due to the rapid intrusion of the underlying magmatic fluids.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030696","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144582136","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":"Spontaneous Initiation and Evolution of Polygonal Fault Systems During the Early Burial of Sediments in 3D Numerical Models","authors":"A. I. Chemenda,&nbsp;G. Ballas,&nbsp;A. Gay","doi":"10.1029/2025JB031506","DOIUrl":"https://doi.org/10.1029/2025JB031506","url":null,"abstract":"&lt;p&gt;Polygonal Fault Systems (PFS) or networks were generated in 3D finite-difference models within the upper (active) layer of two-layer model. The driving force of this process results from a progressive diagenetically induced volumetric contraction (porosity reduction) of the active layer during its burial. This contraction causes extensional strains, reduces horizontal compressive stresses, and increases deviatoric stresses, leading to elastoplastic yielding and strain-softening of the material in this layer. At a certain point, the initially homogeneous material loses stability resulting in deformation bifurcation and localization within narrow deformation bands (incipient faults). The material undergoes progressive failure within the bands, accompanied by the accumulation of the normal-sense displacement along the faults and the evolution of the fault system, with some faults dying and others forming. The fault architecture characterized in the models by depth-dependent fault density and pattern, is remarkably similar to the natural PFS, both buried and exhumed. The fault spacing (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;S&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $S$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) in the models scales with the active layer thickness (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;T&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $T$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) and increases as shear coupling (τ&lt;sub&gt;0&lt;/sub&gt;) between the active and substratum layers decreases. The maximum throw &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;δ&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $delta $&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; along the faults linearly scales with &lt;i&gt;T&lt;/i&gt; and increases with the volume or porosity reduction &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;Δ&lt;/mi&gt;\u0000 &lt;mi&gt;ϕ&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${Delta }phi $&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;. Under the chosen model parameters, the typical &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;δ&lt;/mi&gt;\u0000 &lt;mo&gt;/&lt;/mo&gt;\u0000 &lt;mi&gt;T&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $delta /T$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; ratio of 0.045 for natural PFS, was obtained in the models for &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;Δ&lt;/mi&gt;\u0000 &lt;mi&gt;ϕ&lt;/mi&gt;\u0000 &lt;mo&gt;≈&lt;/mo&gt;\u0000 &lt;mn&gt;7&lt;/mn&gt;\u0000 &lt;mo&gt;%&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${Delta }phi mathit{approx }7mathit{%}$&lt;/","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JB031506","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573680","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":"Development of Low-Angle Boundaries in Amphibole and Their Implications for Accommodating Grain Boundary Sliding in Naturally Deformed Amphibolite","authors":"Jianhua Liu,&nbsp;Shuyun Cao,&nbsp;Xuemei Cheng,&nbsp;Lefan Zhan,&nbsp;Shuting Wang","doi":"10.1029/2024JB031080","DOIUrl":"https://doi.org/10.1029/2024JB031080","url":null,"abstract":"<p>The deformation and interaction of amphibole grains are crucial for comprehending the rheological behavior and physical properties of middle to lower crust. However, the mechanisms of strain accommodation and grain boundary processes in amphibolites are poorly studied. In this study, we analyzed a naturally deformed amphibolite from an exhumed continental strike-slip shear zone. The amphibole grains can be categorized into two distinct types: type I and type II, with the type II being embedded within type I. Type I amphibole grains exhibit typical plastic deformation behavior, distinguished by the presence of discernible dislocation arrays and formation of subgrains. In contrast, type II amphibole grains predominantly display microfractures in the middle of grains and voids occur in their elongated tails. Meanwhile, we identified three types of low-angle boundaries in amphibole grains with varying microstructural and nanoscale characteristics. Our findings indicate that low-angle boundaries in minerals are not exclusively associated with crystal-plastic deformation. Furthermore, the deformation characteristics in type II amphibole grains are related to grain boundary sliding (GBS) process. To relieve stress concentration during grain boundary sliding in type II amphibole grains, two accommodation mechanisms are proposed: (a) Grain boundary diffusion with elimination of grain boundary irregularities. (b) Intragranular deformation of adjacent grains through either a brittle or a ductile process. Our findings hold significant implications for understanding the stress concentration and accommodation during deformation process in amphibolite.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573679","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":"Crystallographic Texture, Structure, and Stress Transmission in Nugget Sandstone Examined With X-Ray Tomography and Diffraction Microscopy","authors":"Ryan C. Hurley,&nbsp;Ye Tian,&nbsp;Mohmad M. Thakur,&nbsp;Jun-Sang Park,&nbsp;Peter Kenesei,&nbsp;Hemant Sharma,&nbsp;Adyota Gupta,&nbsp;Kwangmin Lee","doi":"10.1029/2025JB031690","DOIUrl":"https://doi.org/10.1029/2025JB031690","url":null,"abstract":"<p>Subsurface processes in sandstones are controlled by porosity, permeability, and deformation mechanisms, all of which are controlled by a complex interplay of crystallographic rock texture, structure, and micromechanics. Texture, structure, and micromechanics have historically been studied using optical and electron microscopy of thin-sections. We employed a new combination of in situ X-ray tomography and ray diffraction microscopy to study crystallographic texture, structure, and grain stresses in 3D. We examined these features in a sample of Nugget sandstone, a sandstone constituting hydrocarbon reservoirs across the American West. Our aims are threefold. First, we demonstrate the utility of X-ray diffraction microscopy probes for revealing texture, structure, and stress transmission in 3D. Second, we apply these techniques to Nugget sandstone and discuss findings in the context of prior work. Third, we study grain stress tensor evolution during mechanical compression to examine whether their heterogeneity and orientation evolution reflect that of inter-particle forces in granular materials. Our results show: (a) larger grains featured higher intra-granular misorientations, possibly from an increased prevalence of cements; (b) pores closed parallel to the loading direction and opened normal to loading; (c) grain stresses featured heterogeneity and orientations similar to inter-particle forces in non-cohesive granular materials; (d) grains featured compressive stresses in the loading direction and tensile stresses orthogonal to the loading direction, the latter resisting sample dilation and grain separation. Our work demonstrates the first known application of multi-modal X-ray tomography and diffraction microscopy to sandstone, providing new 3D insight into the nature of quartz cement and stress evolution.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573681","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":"The Effect of Edifice Slope, Failure Surface Geometry, and Magma Intrusion Depth on the Development of Flank Instability at Volcanoes","authors":"J. Gonzalez-Santana,&nbsp;C. Wauthier,&nbsp;S. Tung,&nbsp;T. Masterlark","doi":"10.1029/2024JB030627","DOIUrl":"https://doi.org/10.1029/2024JB030627","url":null,"abstract":"<p>Magmatism is a known driver of flank instability at volcanoes where flank slip has been observed. Studies of instability at Kı̄lauea, Piton de la Fournaise, and Etna imply that long-term flank motion likely requires the presence of a layer accommodating the sliding, and a force, such as magma intrusion, that promotes slip. We present a parametric study using 2D Finite Element Models, to assess how edifice slope, failure surface geometry, edifice asymmetry, and intrusion depth affect the potential for development of flank instability at volcanoes. We quantify whether the tested conditions would favor flank slip based on the Coulomb Stress Changes (CSCs) associated with endmember scenarios and showcase the expected surface displacements for each scenario, to highlight their deviations from half-space models. Development of favored instability is more likely when dike intrusions span an edifice with shallower-dipping failure surfaces, or detachment faults, regardless of edifice steepness. Another favorable scenario occurs in steep edifices with steeply-dipping failure surfaces when the intrusion is beneath the edifice. The same is observed when introducing asymmetry on the opposing flank to simulate buttressing. We also find that neglecting topography yields smaller amplitude displacements with longer wavelengths, and these differences are greater the steeper the volcanic edifice. This topographical effect is more important when modeling horizontal displacements and stress changes induced by shallower intrusions.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030627","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573602","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}