Journal of Geophysical Research: Solid Earth最新文献

{"title":"Crustal Flow-Induced Earthquake Revealed by Full-Waveform Tomography and Implications for Prehistoric Civilization Destruction","authors":"Xingpeng Dong,&nbsp;Dinghui Yang","doi":"10.1029/2024JB029745","DOIUrl":"https://doi.org/10.1029/2024JB029745","url":null,"abstract":"<p>The 2023 Jishishan earthquake resulted in significant casualties and extensive damage to community infrastructure. To understand its seismogenesis, we employed state-of-the-art full-waveform tomography to obtain high-resolution, multiparameter seismic models of the crust surrounding the epicenter. The earthquake's hypocenter was situated in a transition zone with substantial variations in seismic structure. Notably, the mid-lower crust of the plateau's interior exhibited pronounced low-velocity zones, positive radial anisotropy (V_SH &gt; V_SV), and high Vp/Vs ratio. Conversely, the plateau's margin showed relatively high velocities and low Vp/Vs ratio anomalies. Radial anisotropy in the hypocenter region, characterized by negative values (V_SH &lt; V_SV), indicates a predominantly vertical deformation regime. We suggest that the outward flow of mid-lower crustal material, resisted by more stable marginal regions, leads to stress accumulation in the overlying crust, resulting in earthquakes. Furthermore, the destruction of the nearby prehistoric Lajia Ruins, partly attributed to ancient earthquakes, highlights the significant impact of the Tibetan Plateau's lateral expansion on the evolution of surrounding civilizations.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845858","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":"Magnetization of Oceanic Lithosphere From Modeling of Satellite Observations","authors":"Simon Williams,&nbsp;David Gubbins,&nbsp;Joanne Whittaker,&nbsp;Maria Seton","doi":"10.1029/2024JB030370","DOIUrl":"https://doi.org/10.1029/2024JB030370","url":null,"abstract":"<p>Magnetic observations from the oceans have made fundamental contributions to our knowledge of plate motions and the evolution of the geomagnetic field over the past ∼200 Myr. Here we construct updated models of magnetization for the oceanic lithosphere, taking advantage of the most recent models for Earth's past plate motions. We then evaluate these models using maps of the lithospheric field incorporating data from the CHAMP and <i>Swarm</i> satellite missions. Comparison between models and observations shows that satellite anomaly maps robustly capture both edges of the Cretaceous Normal Superchron, but also shorter wavelength anomalies that are clearly linked to the spreading history. Models adopting sloping magnetization boundaries with depth associated with slow cooling of oceanic lithosphere produce a better fit to observations than more simple cases with vertical magnetization boundaries. More complex parameterizations of magnetization acquisition do not improve the fit further. The amplitudes of anomalies adjacent to presently active spreading centers indicate a decrease in magnetization with age for the very youngest seafloor, with parameters consistent with those determined independently from seafloor rock samples. Results illustrate the potential to use satellite magnetic data to refine plate tectonic reconstructions and models of seafloor age in areas where existing shiptrack data are sparse.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030370","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143835948","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":"A Network-Based Phase-Gradient Stacking Method for Resolving Long-Wavelength Deformation From Low-Coherence SAR Interferograms","authors":"Hang Xu,&nbsp;Teng Wang","doi":"10.1029/2024JB030026","DOIUrl":"https://doi.org/10.1029/2024JB030026","url":null,"abstract":"<p>Since the early 1990s, Synthetic Aperture Radar Interferometry (InSAR) has significantly advanced surface deformation measurement across various applications. Despite the successes, InSAR faces challenges in retrieving long-wavelength deformation, particularly in vegetated regions. This is primarily due to the tropospheric phase delays and unwrapping errors. Here we propose a network-based phase-gradient stacking (NPG-Stacking) method that calculates and stacks the phase gradients based on a triangular network connecting iteratively selected high-coherence, residue-free pixels. Afterward, we apply the weighted least squares inversion to retrieve the deformation phase from the stacked phase gradients, during which a posterior test is iteratively conducted to refine the network. Based on these procedures, the NPG-Stacking allows for reducing tropospheric delays without unwrapping individual interferograms. We validate the NPG-Stacking using C-band Sentinel-1 data in three InSAR-challenging scenarios associated with earthquake cycle deformation: the far-field postseismic deformation following the 2011 Tōhoku earthquake, the interseismic deformation along the Median Tectonic Line (MTL) of Japan, and the coseismic deformation of the 2018 Anchorage earthquake in Alaska, where conventional InSAR methods largely failed to produce useable deformation fields. In all the cases, the proposed NPG-Stacking method reveals deformation patterns consistent with the ones interpolated from dense GNSS measurements, with corresponding accuracies of 4.5 mm/yr, 1.35 mm/yr, and 4.93 mm, respectively. Although the NPG-Stacking methods may be limited to retrieving long-wavelength deformation with simple temporal behaviors, the results demonstrate its robustness in low-coherence regions, highlighting its potential to extend the InSAR applicability in challenging environments where conventional methods may fail.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840586","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":"Uniaxial Compression of 3D Printed Samples With Voids: Laboratory Measurements Compared With Predictions From Effective Medium Theory","authors":"Filip P. Adamus,&nbsp;Ashley Stanton-Yonge,&nbsp;Thomas M. Mitchell,&nbsp;David Healy,&nbsp;Philip G. Meredith","doi":"10.1029/2024JB030747","DOIUrl":"https://doi.org/10.1029/2024JB030747","url":null,"abstract":"<p>3D printing technology offers the possibility of producing synthetic samples with accurately defined microstructures. As indicated by effective medium theory (EMT), the shapes, orientations, and sizes of voids significantly affect the overall elastic response of a solid body. By performing uniaxial compression tests on 20 types of 3D-printed samples containing voids of different geometries, we examine whether the measured effective elasticities are accurately predicted by EMT. To manufacture the sample, we selected printers that use different technologies; fused deposition modelling (FDM), and stereolithography (SLA). We show how printer settings (FDM case) or sample cure time (SLA case) affect the measured properties. We also examine the reproducibility of elasticity tests on identically designed samples. To obtain the range of theoretical predictions, we assume either uniform strain or uniform stress. Our study of over two hundred samples shows that measured effective elastic moduli can fit EMT predictions with an error of less than 5% using both FDM and SLA methods if certain printing specifications and sample design considerations are taken into account. Notably, we find that the pore volume fraction of the designed samples should be above <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>≈</mo>\u0000 <mn>1</mn>\u0000 <mi>%</mi>\u0000 </mrow>\u0000 <annotation> ${approx} 1%$</annotation>\u0000 </semantics></math> to induce a measurable softening effect, but below <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>≈</mo>\u0000 <mn>5</mn>\u0000 <mi>%</mi>\u0000 </mrow>\u0000 <annotation> ${approx} 5%$</annotation>\u0000 </semantics></math> to produce accurate EMT estimations that fit the measured elastic properties of the samples. Our results highlight both the strengths of EMT for predicting the effective properties of solids with low pore fraction volume microstructural configurations, and the limitations for high porosity microstructures, particularly, those with interactive pores geometries.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030747","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840587","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":"Is the Geodynamo Characterized by a Distinct Geomagnetic Secular Variation Regime During the Cretaceous Normal Superchron?","authors":"F. Lhuillier,&nbsp;I. E. Lebedev,&nbsp;P. L. Tikhomirov,&nbsp;V. E. Pavlov","doi":"10.1029/2024JB030928","DOIUrl":"https://doi.org/10.1029/2024JB030928","url":null,"abstract":"&lt;p&gt;The Earth's magnetic field stochastically reversed its polarity over geological time, yet enigmatically interrupted this process during the Cretaceous Normal Superchron (CNS; 84–121 Ma). Two scenarios have been proposed in terms of either gradual or abrupt changes to describe the transition of the geodynamo from the CNS to a period with frequent polarity reversals. To discriminate between these two scenarios, we sampled 136 volcanic flows emplaced 66–73 Ma in the eastern part of the Okhotsk-Chukotka Volcanic Belt (NE Eurasia). The 1,700 collected paleomagnetic samples provide, after correction for serial correlation, a robust data set of 112 independent paleodirections characterizing the behavior of the geomagnetic field at a paleolatitude of &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;73&lt;/mn&gt;\u0000 &lt;mo&gt;°&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${sim} 73{}^{circ}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;N shortly after the end of the CNS. Compared to paleomagnetic data from Chukotka and Northern Canada emplaced at similarly high paleolatitude, the dispersion &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;S&lt;/mi&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${S}_{mathrm{B}}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; of the virtual geomagnetic poles, used as a proxy for paleosecular variation (PSV), is 19% (resp. 55%) higher at 66–73 Ma than at the end of CNS when transitional directions are discarded (resp. retained). In contrast, our &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;S&lt;/mi&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${S}_{mathrm{B}}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; value at 66–73 Ma is, whatever the filtering strategy, statistically indistinguishable from the &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;S&lt;/mi&gt;\u0000 &lt;mi&gt;B&lt;/mi&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${S}_{mathrm{B}}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; value at 0–10 Ma derived from the Antarctica and Spitsbergen volcanics. From the viewpoint of PSV observed at high paleolatitude (70–80&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;/mrow&gt;\u0000 &lt;annotation&gt; ${}^{circ}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;), our new results are consistent with an abrupt change between two geodynamo regimes. Nevertheless, once the geodynamo starts reversing its polarity, th","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030928","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831063","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":"Multi-Segment Ruptures of the 2023 Mw 6.0 Jishishan Earthquake, Tibetan Plateau: Implications for Seismogenic Mechanisms of Moderate Earthquakes","authors":"Peng Guo,&nbsp;Zhujun Han,&nbsp;Chao Zhou,&nbsp;Hailong Gai,&nbsp;Pengfei Niu,&nbsp;Xinyu Zhang","doi":"10.1029/2024JB029368","DOIUrl":"https://doi.org/10.1029/2024JB029368","url":null,"abstract":"<p>Because moderate magnitude earthquakes generate significant local ground shaking, but are poorly preserved in the geologic record, they present a major challenge for characterizing seismic hazards along orogenic fronts. The <i>Mw</i> 6.0 Jishishan earthquake and most aftershocks were located to the east of the west-dipping main thrust fault of the Laji Shan, NE Tibetan Plateau, and the earthquake produced serious disaster and surface ruptures, which provides an opportunity to study the rupture patterns and seismogenic mechanisms of moderate earthquakes within the orogenic front. Here we found that it produced three oblique thrusting surface rupture zones with variable lateral components of slip through field investigations and photogrammetry, spanning a total length of ∼8.2 km. The maximum vertical and horizontal displacements of the earthquake were measured as ∼6 and ∼5 cm, respectively. The deep and shallow rupture geometry shows that the seismic faults dip to the east or northeast. Combined with the surveys of pre-existing structures and collected global earthquake cases, we believe that the earthquake is the first reported moderate event (<i>M</i> &lt; 6.5) with multi-segment surface ruptures caused by antithetic thrusting at the front of an orogenic belt. Based upon the analysis of the rupture mechanisms of moderate magnitude earthquakes, we show that four seismogenic models can account for their occurrence along intracontinental orogenic belts, including the shallow thrust, backthrust, blind thrust, and antithetic thrust models. The small or secondary faults in orogenic fronts are worthy of attention in seismic hazard investigations and assessments.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826818","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 Transition From Jointing to Faulting Observed at the Koa'e Fault Zone, Hawai'i Volcanoes National Park, Hawaii","authors":"Hiu Ching Jupiter Cheng,&nbsp;Jay Mrazek,&nbsp;Christian Klimczak","doi":"10.1029/2024JB030416","DOIUrl":"https://doi.org/10.1029/2024JB030416","url":null,"abstract":"<p>Fractures can exhibit mixed modes of displacement, that is, combinations of displacements parallel and perpendicular to the fracture plane, that make a displacement-to-length (<i>D</i>_max/<i>L</i>) scaling analysis challenging. However, such analysis is important for understanding the propagation and nature of mixed-mode fracture populations. In this study, we investigate the <i>D</i>_max/<i>L</i> scaling relationship for fractures involving opening and shearing modes from field measurements at the spectacularly exposed Koa'e Fault Zone in Hawai'i Volcanoes National Park, Hawaii. Its major structures have prominent fault scarps and display openings of up to several meters. They are locally accompanied by monoclines and sheared and pure joints. Through structural mapping and detailed field observations, we identify a morphological continuum along the structures representing different stages in the evolution of the faults. Contrary to previous studies, our observations support that faults are formed by the downward propagation of joints that transition to faulting at depth, then creating the monoclinal flexure. Our measurements allow us to investigate the <i>D</i>_max/<i>L</i> scaling behavior for the total mixed-mode displacement and their individual vector components, that is, reliefs and openings. The <i>D</i>_max/<i>L</i> scaling relationships for all structure types, including pure joints, sheared joints, and faults, show a power-law relation with a near-linear dependence of maximum displacement and length. The joint apertures scale to length with a nearly linear scaling relationship, not following the widely observed square root scaling relationship that all opening-mode fractures are believed to have.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030416","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826956","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":"Geophysical Investigations of the Fujairah Basin, East Coast of United Arab Emirates: Insights Into Tectonic Evolution","authors":"M. Y. Ali,&nbsp;M. Ismaiel,&nbsp;A. Abdelmaksoud,&nbsp;S. Pilia,&nbsp;A. B. Watts,&nbsp;M. P. Searle","doi":"10.1029/2024JB030345","DOIUrl":"https://doi.org/10.1029/2024JB030345","url":null,"abstract":"<p>The Fujairah basin in the Gulf of Oman experienced a complex tectonic evolution related to Late Cretaceous ophiolite obduction and Oligocene-Miocene Zagros continental collision. The structure of the foreland basin in Oman-UAE is well-known, but the structure and evolution of the hinterland basin behind the obducted ophiolite and underlying thrust sheets are less understood. Therefore, we use a combination of seismic reflection interpretation, gravity and magnetic forward modeling, and backstripping of well data to investigate the spatio-temporal deformation pattern in the basin and its connection with regional tectonics operating at the Central Iran/Arabia Plate boundary. The ophiolite complex in the Gulf of Oman is characterized by high-amplitude Bouguer gravity anomalies (&gt;120 mGal) and short-wavelength (∼10 km) magnetic anomalies with a predominant north-south orientation along the coast. The top of the ophiolite/Cretaceous oceanic crust ranges in depth from 1 to 10 km, and up to 9 km of Upper Cretaceous-Holocene sedimentary successions underlies the shelf of the Gulf of Oman margin. Normal faults are interpreted within the Neogene and Quaternary, while reverse faults are confined to the lower Miocene to Upper Cretaceous. NW-SE to NNW-SSE-oriented reverse faults exhibit dominant dips ranging from 40° to 80°, while normal faults oriented mainly in the N-S direction display dominant dips of 40°–65°. Seismic and backstripping analysis of biostratigraphic data in wells reflects an Oligocene-early Miocene compressional event due to the collision of the Arabian and Central Iran plates and late Miocene-Holocene extensional event. Onshore in the Musandam Peninsula, west-vergent thrusts such as the Hagab thrust were active synchronously with N-S-oriented normal faults along the east coast of Musandam. A more recent extensional event is linked to transtensional movement resulting from the varying convergence rates along the Minab-Zendan strike-slip fault.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030345","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831338","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":"Along-Dip Variations in Source Characteristics of Shallow Slow Earthquakes Controlled by Topography of Subducted Oceanic Plate","authors":"Shunsuke Takemura,&nbsp;Suguru Yabe,&nbsp;Kentaro Emoto,&nbsp;Satoru Baba","doi":"10.1029/2024JB030751","DOIUrl":"https://doi.org/10.1029/2024JB030751","url":null,"abstract":"<p>To discuss slip behaviors in shallow slow earthquake regions, we investigate source characteristics of shallow very low frequency earthquakes (VLFEs) southeast off the Kii Peninsula in the Nankai subduction zone. Very low frequency earthquakes are a kind of slow earthquake and are clearly observed at frequencies below 0.1 Hz. A non-linear inversion technique for moment rate function estimation and the permanent ocean-bottom seismometer network provided us with precise locations and detailed kinematic source characteristics of shallow VLFEs. The high activity of shallow VLFEs around the western edge of the subducted Paleo-Zenisu ridge is similar to previous studies. A notable trend change in the along-dip dependency of shallow VLFE moment rates was found. Along the profile west side of the Paleo-Zenisu ridge, moment rates of shallow VLFEs increase with reaching the megathrust zone. Small-scale topographic fluctuations of the subducted oceanic plate exist along this profile, but large-scale seamount subduction has not been identified even from dense seismic surveys. Similar tendencies have been reported in tectonic tremors in the Nankai and Cascadia subduction zones. On the other hand, the opposite trend appeared along the profile with the Paleo-Zenisu ridge. Small shallow VLFEs were dominant near the summit of the Paleo-Zenisu ridge. Fracture networks or stress fields due to seamount subduction possibly impede large shallow VLFEs around the subducted seamount. Our results suggest that the large-scale heterogeneity of the upper surface of the subducted oceanic plate could control source characteristics of shallow slow earthquakes.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030751","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831394","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 Shallow Aseismic Deformation Along the Dead Sea Pull-Apart Basin Using Geodetic Observations","authors":"Yariv Hamiel,&nbsp;Roger Bilham,&nbsp;Oksana Piatibratova","doi":"10.1029/2024JB030191","DOIUrl":"https://doi.org/10.1029/2024JB030191","url":null,"abstract":"<p>We use creepmeter (CM), Global Navigation Satellite System (GNSS), Interferometric Synthetic Aperture Radar (InSAR) and airborne Light Detection and Ranging (LiDAR) observations to characterize transient aseismic deformation along the central Dead Sea pull-apart basin, which is located at the southern part of the sinistral Dead Sea Fault (DSF). A biaxial creepmeter was installed in early 2021 across a previously unmapped oblique-slip fault, measuring a combination of dip-slip and strike-slip, and providing the first evidence of creep events along the DSF. The creepmeter records predominantly normal faulting, at an average dip-slip creep rate of 22.2 mm/yr, among the highest in the world. This large rate is also evident with the ∼30 cm of subsidence recorded between 2017 and 2019 using differential LiDAR data. The data reveal seasonally variable dip-slip on the fault with a maximum rate of ∼0.5 μm/hr starting in August/September and approaching zero (mm/yr) in April. The creepmeter also records sinistral slip with an average rate of 1.3 mm/yr, about half of the total rate that was observed for the western side of the basin. Small Baseline Subset analysis of InSAR data indicate up to 13 mm/yr of line-of-sight displacement across the inferred fault. GNSS and InSAR data reveal high subsidence rate within the basin, between the western inferred fault and the Lisan salt diapir at the east and mostly along the shores of the lake. Our results indicate that deformation within the Dead Sea basin is not solely controlled by active tectonics. The observed vertical deformation is modulated by the thermo-elastic response of sediments and variations in local conditions, such as sediment compaction and fluid-pressure changes.</p>","PeriodicalId":15864,"journal":{"name":"Journal of Geophysical Research: Solid Earth","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JB030191","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143831207","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}