pure and applied geophysics最新文献

{"title":"Dynamic Triggering of Seismicity in the Hindu Kush–Tien Shan Region","authors":"Mayank Dixit,&nbsp;Tony Saini,&nbsp;Abhey Ram Bansal","doi":"10.1007/s00024-026-03965-6","DOIUrl":"10.1007/s00024-026-03965-6","url":null,"abstract":"<div><p>The remote triggering of seismicity, controlled by dynamic stresses induced by surface waves of large teleseismic earthquakes, is a recognized and commonly observed phenomenon across a variety of tectonic environments. The collision of tectonic plates in the western Himalayas generates frequent seismic activity, making the region a focal point for seismological studies. In this study, we conducted a systematic investigation of triggered seismicity in the Hindu Kush–Pamir–Tien Shan region using 26 years of continuous waveform data (December 1995–August 2021) from 55 large and shallow teleseismic earthquakes that produced dynamic stress of at least one kPa. Continuous waveform data from 31 seismic stations were analysed manually and using the STA/LTA (short-term average/long-term average) method. Our analysis revealed triggered tremors and earthquakes in the Hindu Kush and Tien Shan areas, influenced by both Love and Rayleigh waves from significant events, including the November 8, 1997 <span>({text{M}}_{text{w}})</span> 7.4 Xizang, November 14, 2001 <span>({text{M}}_{text{w}})</span> 7.8 Qinghai, December 26, 2004 <span>({text{M}}_{text{w}})</span> 9.0 Sumatra, March 11, 2011 <span>({text{M}}_{text{w}})</span> 9.1 Tohoku-Oki, April 25, 2015 <span>({text{M}}_{text{w}})</span> 7.9 Nepal, and the April 12, 2012 <span>({text{M}}_{text{w}})</span> 8.6 Indian Ocean earthquake and its largest aftershock of <span>({text{M}}_{text{w}})</span> 8.2. We found the β-values &gt; 2 for all the triggered events, indicating that statistically significant increase in the seismicity. Interestingly, low-frequency surface waves were identified as the primary drivers of both instantaneous and delayed dynamic triggering, rather than intermediate or ultra-low frequencies. Several high-magnitude mainshocks with substantial dynamic stress, such as the April 2013 <span>({text{M}}_{text{w}})</span> 7.7 Iran, September 2013 <span>({text{M}}_{text{w}})</span> 7.7 Pakistan, and February 2010 <span>({text{M}}_{text{w}})</span> 8.8 Chile earthquakes, did not trigger detectable seismicity in the region. Furthermore, global comparisons suggest that the triggering threshold in the Hindu Kush region is slightly higher than in other tectonic settings. These findings underscore the importance of studying triggered seismicity to enhance our understanding of dynamic stress sensitivity and seismic hazard potential in the region.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2105 - 2122"},"PeriodicalIF":1.9,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CHIRPWeb, an Online Tool for Providing a Bias Corrected CHIRP Grid Dataset Using Field Measurements","authors":"Julio Pérez-Sánchez,&nbsp;Patricia Jimeno-Sáez,&nbsp;Adrián López-Ballesteros,&nbsp;José Ginés Giménez,&nbsp;José M. Cecilia,&nbsp;Javier Senent-Aparicio","doi":"10.1007/s00024-026-03966-5","DOIUrl":"10.1007/s00024-026-03966-5","url":null,"abstract":"<div><p>Precipitation data play a crucial role in hydrological modeling. Although rain ground stations data have traditionally been used, their uneven distribution and numerous gaps raise some doubts about their reliability. As a result, satellite rainfall data sets are increasingly used in hydrological assessments. However, these estimates are prone to inaccuracies due to instrumental problems or theoretical simplifications, and it is essential to eliminate systematic errors before using them in hydrological applications. This paper presents an online tool to select a CHIRP grid in a region and correct its bias derived from field measurements. Furthermore, the tool is designed to generate SWAT-compatible rainfall data input. As an example of the application, the performance of the SWAT model in the Spanish Oskotz river basin has been evaluated. In general, better results are achieved with the corrected grids, obtaining improvements of around 30% in Nash–Sutcliffe efficiency and decreasing PBIAS by around 15%.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2181 - 2194"},"PeriodicalIF":1.9,"publicationDate":"2026-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00024-026-03966-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Modeling 2010 Maule Earthquake Rupture Heterogeneity Reveals Impacts on Ground Motion Landslides and Crustal Faults","authors":"Patricio Venegas-Aravena","doi":"10.1007/s00024-026-03971-8","DOIUrl":"10.1007/s00024-026-03971-8","url":null,"abstract":"<div><p>The 2010 Maule earthquake (Mw 8.8) is a well-recorded megathrust event. Despite this, the role of fault’s heterogeneities in shaping ground motion patterns and their consequences has not been fully characterized. In this study, we use a numerical model to simulate heterogeneous rupture under a homogeneous elastic medium. We evaluate the spatial distribution of peak ground velocity (PGV), peak ground acceleration (PGA), and far-field P-wave corner frequency to investigate their association with landslides and crustal fault activation. Results indicates that rupture front accelerations lead to directivity effects that concentrate high PGV, PGA, and corner frequency values toward the seafloor and coastal areas (rays). It is found that approximately 80% of non-mountain landslides are the product of these rays and no landslides occurred where horizontal ground motion was less than 95% of the total motion, underscoring the dominant role of near-pure horizontal shaking in their initiation. While lithology and topography were not included, results suggest that seismic source alone could explain the observed landslide distribution. Finally, crustal faults appear to align with sharp transitions in corner frequency, indicating a potential structural inheritance from past similar events supporting the interpretation of the Maule earthquake as a repeating rupture process.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2075 - 2104"},"PeriodicalIF":1.9,"publicationDate":"2026-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Local Scour Process in Conduit Aerated Water Jets","authors":"M. Cihat Tuna,&nbsp;Ramazan Acar,&nbsp;Mustafa Tunç","doi":"10.1007/s00024-026-03964-7","DOIUrl":"10.1007/s00024-026-03964-7","url":null,"abstract":"<div><p>High-velocity water jets emerging from hydraulic structures cause local scouring in downstream areas, creating significant risks to structural safety. In this study, the effects of natural aeration provided through pressurized pipes on jet-induced scouring were investigated through laboratory experiments. A total of 60 experiments were conducted for different gate openings, flow rates, and downstream water levels; the scour geometries created by aerated and non-aerated jets were compared. The aeration level was defined by the dimensionless air-to-water flow ratio (Q_a/Q_w); maximum scour depth, scour length, scour slope angle, and jet fall distance were considered as basic evaluation parameters. The experimental results showed that increased aeration significantly reduced the maximum scour depth and scour length while moving the point of contact of the jet further upstream. While the scour depth and slope angles reached their highest values in non-aerated jets, shallower and flatter scour profiles were formed in aerated conditions. An empirical relationship predicting the maximum scour depth using experimental data has been developed and found to be in high correlation with the measured values (R² = 0.93). The findings reveal that channel aeration is an effective method for reducing scouring and demonstrate that this approach can be considered a safe and economical alternative in the design of spillways, wastewater treatment plants, and similar hydraulic systems.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2373 - 2393"},"PeriodicalIF":1.9,"publicationDate":"2026-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00024-026-03964-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Hydrogeophysical Constraints on Fracture-Mediated Groundwater Flow and Contamination in the Southeastern Cameroon Volcanic Line","authors":"Kevin Zebaze,&nbsp;Anatole Eugene Djieto Lordon,&nbsp;Jidong Yang,&nbsp;Engome Regina Wotany,&nbsp;Jianping Huang,&nbsp;Mouasso Parfaite,&nbsp;Clotaire José Pako Perabi,&nbsp;Arthur Paterne Mioumnde,&nbsp;Bekoa Ateba,&nbsp;Victor Sedziafa,&nbsp;Christopher M. Agyingi","doi":"10.1007/s00024-026-03969-2","DOIUrl":"10.1007/s00024-026-03969-2","url":null,"abstract":"<div><p>Groundwater scarcity poses a major challenge to sustainable development in many developing countries, particularly in regions dependent on groundwater for domestic, agricultural, and industrial uses. This study integrates geophysical and hydrogeochemical approaches to characterize aquifer properties and water quality southeast of the Cameroon Volcanic Line in Souza city. Four geoelectric and seismoelectric profiles were acquired alongside 25 groundwater samples for hydrochemical and statistical analysis. Resistivity anomalies with low to moderate values delineate permeable sand aquifers, 10–20 m thick, occurring at variable depths. Groundwater is generally acidic with limited salinity variation. Potassium concentrations range from 0.05 to 20.85 mg/L, with one sample exceeding the 12 mg/L guideline, while nitrate varies between 0.40 and 81.63 mg/L, with 90% of samples below the WHO limit of 50 mg/L. Hydrochemical facies (Na–Cl, Ca–Mg–Cl, and Ca–Mg–HCO₃) indicate dominant rock–water interactions, and recharge is primarily driven by precipitation. Water quality is generally suitable for domestic and industrial use, while irrigation suitability is limited to peripheral areas. High concentration of nitrate and potassium levels suggest localized impacts from agricultural and municipal activities. Targeted monitoring, public awareness, and appropriate water treatment strategies are recommended to mitigate anthropogenic contamination and support sustainable groundwater management in coastal and transitional basins.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2413 - 2443"},"PeriodicalIF":1.9,"publicationDate":"2026-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00024-026-03969-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Analysis of the Electrokinetic Coupling Phenomena at Partial Saturation: Insights from an Extended Pride’s Theory","authors":"Leonardo B. Monachesi,&nbsp;Fabio I. Zyserman,&nbsp;Laurence Jouniaux,&nbsp;Arthur H. Thompson","doi":"10.1007/s00024-026-03959-4","DOIUrl":"10.1007/s00024-026-03959-4","url":null,"abstract":"<div><p>We present an analysis of the electrokinetic coupling equations developed in a previous work by the same authors, where an extension to Pride’s theory encompassing partially saturated porous rocks was derived. One of the main hypotheses of the model establishes that the non-wetting fluid phase must be connected across the averaging volume, which may not be the case near full wetting phase saturation. This constraint is removed by developing new expressions for the model parameters, such as electric conductivity and electrokinetic coupling coefficient, accounting for the disconnection of the non-wetting fluid near full saturation. We study their sensitivity to the salinity of the electrolyte and to geometric parameters, such as porosity, tortuosity, and volume-to-surface ratio of the non-wetting fluid. Moreover, we consider different sets of values of the two different zeta potentials present in the model, one of which originates at the pore-wall/wetting-fluid interface and the other at the wetting/non-wetting fluid interface. Our model predicts that the electric conductivity, the electrokinetic coupling coefficient, and the streaming potential coefficient may show either a monotonic or a non-monotonic behaviour as a function of water saturation, depending on water salinity and geometrical parameters, and they tend to the corresponding saturated values predicted by Pride when water saturation tends to one. We show that the electric conductivity model predictions are in good agreement with data sets from the literature. Further, we numerically simulate the electrokinetic coupling phenomenon during drainage experiments over a rock column. The so-obtained ratio of the electric potential difference to the water pressure variation reproduces the main features of previously published data obtained in laboratory measurements for clean rocks.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2343 - 2371"},"PeriodicalIF":1.9,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experiments on Stress Drop and Rupture Evolution of Laboratory Earthquake Under Water-Saturated Environment with Different Fluid Pressure","authors":"Lili Lu,&nbsp;Shunyun Chen,&nbsp;Yanqun Zhuo,&nbsp;Hao Chen,&nbsp;Zihong Li,&nbsp;Qiongying Liu","doi":"10.1007/s00024-026-03962-9","DOIUrl":"10.1007/s00024-026-03962-9","url":null,"abstract":"<div><p>Earthquakes are significantly influenced by fluid pressure which largely depend on the fault hydraulic connectivity, and however, the effect of hydraulic conditions remains poorly understood. In this study, we conducted a series of stick–slip (laboratory-earthquake) experiments under three fault hydraulic conditions connected incompletely, locally or uniformly with a water-saturated environment at different fluid pressures, using various loading rates. The main findings include: (1) The shear stress drop of stick–slip events decreases with the increase of the fluid pressure, which is accordant with the theoretical expectation. (2) Shear stress drop shows little association with the fault hydraulic connectivity, which implies that shear stress drop is independent of fluid pressure distribution along the fault plane. (3) For comparison, the pattern of rupture propagation under room-dry condition was also obtained, and the corresponding rupture patterns for the three fault hydraulic connectivity types are generally similar. (4) Rupture pattern of laboratory-earthquake under water-saturated environment with different fluid pressure is strongly affected by the fault’s hydraulic connectivity. Even, the rupture patterns can alter from bilateral to unilateral propagation. This means that the rupture pattern strongly depends on the distribution of effective normal stress along the fault plane. In short, our findings provide insights into the role of hydraulic connectivity in modulating the interplay between fluid pressure, loading rate, and fault instability.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2123 - 2146"},"PeriodicalIF":1.9,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Ionospheric Disturbances Due to the 2024 Japan Earthquake, Typhoon Seroja 2021 and Koinu 2023 Using 3D Tomography","authors":"Dwi Sri Lestari,&nbsp;Mokhamad Nur Cahyadi,&nbsp;Buldan Muslim,&nbsp;Ihsan Naufal Muafiry,&nbsp;Nilam Komalasari,&nbsp;Nurrohmat Widjajanti,&nbsp;Evi Aprianti,&nbsp;Deni Kusumawardani,&nbsp;Candida Aulia De Silva Nusantara,&nbsp;Yessi Rahmawati,&nbsp;Zambri Harun,&nbsp;Siti Asmayanti Tuasamu","doi":"10.1007/s00024-026-03954-9","DOIUrl":"10.1007/s00024-026-03954-9","url":null,"abstract":"<div><p>Typhoon and earthquake are natural disasters that have the potential to damage infrastructure and cause casualties, showing the need for further mitigation studies. These natural disasters often cause ionospheric disturbance that can be observed through changes in TEC values using GNSS technology. Therefore, this study aims to measure the mechanism of ionospheric disturbance due to Typhoon Seroja 2021, Typhoon Koinu 2023, and the 2024 M7.5 Japanese earthquake using GNSS-TEC and 3D tomography methods. The analysis was carried out with physical parameters in the form of TEC values, wave propagation speed, frequency spectrum, and spatial–temporal changes from the results of the 3D tomography model. The results showed that earthquake and typhoon caused ionospheric disturbance known as Coseismic Ionospheric Disturbance (CIDs) and Concentric Traveling Ionospheric Disturbance (CTIDs). CID due to the Japanese earthquake led to a TEC change of ~ 1.199 TECU with a period of ~ 5 min, while CTIDs due to Typhoon Seroja and Koinu caused a change of − 0.26–0.73 TECU with a period of 18–71 min. In addition, CIDs from earthquake are short periods but have larger amplitude than CTIDs caused by typhoons, which have a longer duration and smaller amplitude. The results of 3D tomography modeling showed differences in ionospheric disturbance patterns and heights. Ionospheric disturbance due to the Japanese earthquake are distributed around the epicenter, while those from Typhoon Seroja and Koinu are distributed in azimuth 0–150° and 180–240°, respectively, both of which followed the direction of typhoon movement. The tomographic data show that the maximum height of ionospheric disturbance due to the earthquake is higher than that of the typhoon. The results of this study have the potential to be used in the development of disaster early warning systems in the future.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2147 - 2179"},"PeriodicalIF":1.9,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Iterative Regularisation and Uncertainty Propagation in Solving Ill-Posed Problems: A GOCE-Based Regional Gravity Field Modelling","authors":"Mehdi Eshagh","doi":"10.1007/s00024-026-03933-0","DOIUrl":"10.1007/s00024-026-03933-0","url":null,"abstract":"<div><p>Inverse problems are fundamental in geoscience, enabling estimation of Earth’s physical properties that cannot be measured directly. These problems are typically ill-posed, meaning their solutions are highly sensitive to noise and variability in observational data, and thus require regularisation to ensure stability. Both direct and iterative regularisation methods have been extensively studied across geoscientific applications. However, accurately quantifying uncertainty—particularly for iterative regularisation—remains a major challenge, as uncertainty estimation in these methods is less well understood. This study examines the performance and uncertainty characteristics of four iterative regularisation techniques—conjugate gradient least-squares (CGLS), minimum residual 2 (MR2), algebraic reconstruction technique (ART), and the <i>ν</i>-method (Nu). Here, a comprehensive conceptual overview of these methods is provided, along with an evaluation of two internal uncertainty quantification approaches: (a) the error propagation using numerical Jacobians, and (b) the Monte Carlo method. Although computationally demanding, these techniques offer valuable insights into how observational errors propagate through nonlinear iterative processes. The methods are applied to the regional recovery of gravity anomalies at sea level from the Gravity field and steady-state Ocean Circulation Explorer (GOCE) 2nd-order radial gradients over Alpine and surrounding south-central European region as a case study. Results demonstrate that different iterative techniques yield distinct solutions even under identical regularisation criteria (e.g., the L-curve), and that the magnitude of propagated error alone is not a reliable indicator of solution quality. The estimated gravity anomalies and their uncertainties by the MR2 and ART are close to each other. Nu provides faster, smoother solutions with lower uncertainties, while the CGLS preserves more high-frequency geophysical signals at the cost of higher propagated errors. Error propagation with numerical Jacobians produces smaller error estimates compared to with the Monte Carlo method, which consistently reports larger uncertainties, reflecting its ability to account for both random noise and nonlinear effects. The difference between the estimated uncertainties by these methods over the study area are around 2 mGal or less.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2217 - 2242"},"PeriodicalIF":1.9,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00024-026-03933-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Analysis and Numerical Simulation of Mechanical Response of Sandstone under Variable Frequency Cyclic Loading","authors":"Dongxu Zhang,&nbsp;Yifan Zhang,&nbsp;Haoran Zhang,&nbsp;Songmei Li,&nbsp;Nan Qin","doi":"10.1007/s00024-026-03956-7","DOIUrl":"10.1007/s00024-026-03956-7","url":null,"abstract":"<div><p>This study investigates the mechanism of damage evolution in sandstone under variable-frequency cyclic loading, employing a combination of experimental and numerical simulations. It examines the mechanical response and damage evolution behavior of sandstone subjected to increasing (0.08 Hz → 0.14 Hz, 2.0 Hz → 8.0 Hz) and decreasing (0.14 Hz → 0.08 Hz, 8.0 Hz → 2.0 Hz) cyclic loading frequencies. The experiments were performed at different levels of initial stress, with a systematic analysis of strain evolution, elastic modulus degradation, and energy evolution characteristics. The findings suggest that the initial stress level significantly impacts the accumulation of irreversible strain, modulus attenuation, and energy input. The frequency path also markedly influences dissipated energy, with low frequencies facilitating energy dissipation and high frequencies inhibiting its progression. Additionally, a PFC2D particle flow model was used to simulate the high-frequency loading process, revealing the mechanism by which the frequency path influences the evolution of micro-scale energies, such as cementation strain energy and frictional dissipation energy. This study contributes a theoretical and numerical foundation for the assessment of rock damage under variable-frequency cyclic loading.</p></div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"183 5","pages":"2267 - 2292"},"PeriodicalIF":1.9,"publicationDate":"2026-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00024-026-03956-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147863123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}