Acta Geophysica最新文献_第3页

Estimation of site effects and seismic Q factor using generalized inversion technique (GIT) in Northern Egypt 利用广义反演技术估算埃及北部地区的场地效应和地震Q因子

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-04-13 DOI: 10.1007/s11600-026-01862-z

Hamada Saadalla, Saleh Qaysi, Abdalla Abdelnabi

{"title":"Estimation of site effects and seismic Q factor using generalized inversion technique (GIT) in Northern Egypt","authors":"Hamada Saadalla, Saleh Qaysi, Abdalla Abdelnabi","doi":"10.1007/s11600-026-01862-z","DOIUrl":"10.1007/s11600-026-01862-z","url":null,"abstract":"<div><p>Northeastern Egypt and its adjoining seismic regions (Cairo-Suez district, Gulf of Suez, Triple Junction, Gulf of Aqaba) have historically experienced moderate-to-large earthquakes, highlighting the need for a detailed understanding of path attenuation and site response characteristics for effective seismic hazard assessment and mitigation. This study employs the generalized inversion technique (GIT) to estimate path attenuation and site parameters using earthquake recordings from multiple seismic stations in the region with magnitude larger than 3.0. In the first step of the inversion process, observed seismograms are decomposed into source, path, and site contributions, with a reference site constraint applied to ensure consistency in spectral decomposition and address the degrees of freedom issue and the trade-off between the decomposed factors. The attenuation models are developed as frequency-dependent functions, yielding the following S-wave quality factors: <span>({Q}_{text{S}}=162pm 5.7 {f}^{0.86pm 0.05})</span>(NBST-reference site) and <span>({Q}_{text{S}}=166pm 3.2 {f}^{0.84pm 0.04})</span>(TAMR-reference site). The frequency-dependent quality factor (<span>({Q}_{text{f}})</span>) relationship indicates a low reference quality factor at 1 Hz (<span>({Q}_{0})</span> < 200) and a strong frequency dependence (<span>(n)</span> > 0.8), characteristic of tectonically and seismically active regions. In the second step, site amplification characteristics at each recording station are quantified using site spectral amplitude ratios of horizontal to vertical components. Additionally, the predominant frequency at each recording station was calculated using the horizontal-to-vertical spectral ratio (HVSR) method. The predominant frequency values obtained from the HVSR method closely match those derived from the generalized inversion analysis at each station. The predominant frequencies obtained from these amplification curves allow for site classification, providing crucial insights into local site effects.</p></div>","PeriodicalId":6988,"journal":{"name":"Acta Geophysica","volume":"74 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147665693","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}

引用次数: 0

Estimation of return levels with the generalised F distribution 广义F分布下的收益水平估计

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-04-13 DOI: 10.1007/s11600-026-01860-1

Jesper Rydén

引用次数: 0

An integrated SWAT–SDSM–QDM framework for assessing climate change impacts in a climatic transition basin 气候转型盆地气候变化影响评估的SWAT-SDSM-QDM综合框架

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-04-13 DOI: 10.1007/s11600-026-01865-w

Sefa Furkan Selçuk, Burcu Çirci Selçuk

{"title":"An integrated SWAT–SDSM–QDM framework for assessing climate change impacts in a climatic transition basin","authors":"Sefa Furkan Selçuk, Burcu Çirci Selçuk","doi":"10.1007/s11600-026-01865-w","DOIUrl":"10.1007/s11600-026-01865-w","url":null,"abstract":"<div><p>In this study, a novel integrated hydrological–climate modeling framework combining the Soil and Water Assessment Tool, the Statistical DownScaling Model, and the Quantile Delta Mapping method was applied to the Kelkit Basin, which is located in a climatic transition zone. To the best of our knowledge, the joint application of these three components within a single integrated framework has not been previously reported in the literature. This approach enhances the reliability of local-scale climate and hydrological projections and provides a transferable methodological reference for other climate-sensitive basins. The model calibration and validation yielded satisfactory to very good performance, with NSE, <i>R</i><sup>2</sup>, and KGE values ranging between 0.79–0.88, 0.84–0.89, and 0.83–0.92 in sub-basins with natural flow regimes, while the dam-affected sub-basin showed satisfactory validation performance (NSE = 0.50). Future projections indicate substantial changes in basin water potential. Under the SSP5 scenario, precipitation increased by up to 82% and blue water potential increased by 129–270% in the far future (2076–2100), depending on the sub-basin. In contrast, green water storage decreased by up to 8–13%, particularly during summer months, reflecting enhanced evapotranspiration and soil moisture depletion. Increases in green water flow may support plant growth in the short term; however, soil moisture losses could threaten agricultural productivity and ecosystem sustainability in the long term. In addition, the rise in blue water components increases potential flood risks. The findings demonstrate that the Kelkit Basin possesses a complex hydrological structure that contains both opportunities and risks in the face of climate change.</p></div>","PeriodicalId":6988,"journal":{"name":"Acta Geophysica","volume":"74 3","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11600-026-01865-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147665695","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}

引用次数: 0

Enhancing large-scale basin rainfall-runoff modelling through the integration of flow routing: a case study in Iran’s Karun-4 Basin 通过整合水流路径加强大尺度流域降雨径流模拟：以伊朗Karun-4流域为例

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-04-06 DOI: 10.1007/s11600-026-01825-4

Samira Bayati, Khodayar Abdollahi, Afshin Honarbakhsh, Mohammad-Ali Nasr Esfahani

{"title":"Enhancing large-scale basin rainfall-runoff modelling through the integration of flow routing: a case study in Iran’s Karun-4 Basin","authors":"Samira Bayati, Khodayar Abdollahi, Afshin Honarbakhsh, Mohammad-Ali Nasr Esfahani","doi":"10.1007/s11600-026-01825-4","DOIUrl":"10.1007/s11600-026-01825-4","url":null,"abstract":"<div><p>Flow routing in rivers is essential for effective surface water management and the strategic design of flood control systems. This study explores the role of considering/ignoring the flow routing component in a daily rainfall-runoff simulation. Hydrological modeling for the basin of interest was conducted using a daily water balance model with two scenarios: one incorporating flow routing and the other omitting it. The results of this model were compared with those of the Exp-Hydro model, which this Python-coded model shares a simple structure and requires minimal input data (daily precipitation, temperature, runoff, and potential evapotranspiration). The study period spanned from 2000 to 2020, with two-thirds of the data allocated for calibration and one-third for validation. Performance assessment of the daily water balance models revealed that the developed model, boasting Nash–Sutcliffe and Kling Gupta coefficients of 0.71 and 0.75, respectively, surpassed the Exp-Hydro model, which yielded values of 0.37 and 0.69, during the calibration period. Notably, the incorporation of flow routing significantly enhanced the performance of the developed model in flow simulation. This study provides valuable insights for rainfall-runoff simulation in data-scarce large-scale basins, favoring the adoption of lumped models over data-intensive distribution models. While integrated models, often criticized for neglecting spatial parameter variations, have exhibited promising results in various studies, their performance can vary between basins due to differing influential factors. Daily flow routing emerged as a pivotal factor, as demonstrated by this study, emphasizing its significance for improving discharge simulations, particularly in large basins.</p></div>","PeriodicalId":6988,"journal":{"name":"Acta Geophysica","volume":"74 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147642684","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}

引用次数: 0

Urban meander loop dynamics and future projections: insights from the Barak River, India 城市蜿蜒循环动态和未来预测：来自印度巴拉克河的见解

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-04-06 DOI: 10.1007/s11600-026-01864-x

Wajahat Annayat

{"title":"Urban meander loop dynamics and future projections: insights from the Barak River, India","authors":"Wajahat Annayat","doi":"10.1007/s11600-026-01864-x","DOIUrl":"10.1007/s11600-026-01864-x","url":null,"abstract":"<div><p>The Barak River is recognised as one of the most highly meandering rivers in Northeast India, which presents considerable challenges for local communities, particularly during flood events. This study conducts a thorough investigation into the geomorphological transformations occurring within an urban meander loop situated in the centre of Silchar city, Assam, India. Morphometric analysis of meander characteristics, including length, width, ratio, wavelength, sinuosity, and radius of curvature reveal noticeable variations over the study period. While descriptive analysis indicates increases in meander length, width, ratio, and wavelength, along with decreases in sinuosity and radius of curvature, statistical testing shows that these changes are not significant at the 5% confidence level, suggesting localized and episodic channel adjustments rather than a persistent long-term trend. A comprehensive land use and land cover analysis of the urban meander loop reveals a significant increase in settlements by 16.18%, accompanied by reductions in water bodies (0.57%), dense vegetation (2.58%), and agricultural land (13.16%). The Auto Regressive Integrated Moving Average (ARIMA) model was employed to facilitate predictive analysis to forecast channel shifting trends up to the year 2030. The results indicate that the channel in the urban meander loop is undergoing erratic changes, shifting either to the right or left. There is a high correlation between the observed and the predicted values, with an R<sup>2</sup> value of 0.8. The persistent uncertainty in channel movements is anticipated to pose ongoing threats to nearby settlements and significantly alter existing land use in the foreseeable future.</p></div>","PeriodicalId":6988,"journal":{"name":"Acta Geophysica","volume":"74 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147642683","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}

引用次数: 0

Effect of outlet step edges on local scour downstream of Type B trapezoidal piano key weirs 出口台阶边缘对B型梯形钢琴键堰下游局部冲刷的影响

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-03-30 DOI: 10.1007/s11600-026-01807-6

Amirhossein Fathi, Wadi Mohammed Wadi, Ali Khoshfetrat, Masoud Ghodsian, Ehsan Delavari

{"title":"Effect of outlet step edges on local scour downstream of Type B trapezoidal piano key weirs","authors":"Amirhossein Fathi, Wadi Mohammed Wadi, Ali Khoshfetrat, Masoud Ghodsian, Ehsan Delavari","doi":"10.1007/s11600-026-01807-6","DOIUrl":"10.1007/s11600-026-01807-6","url":null,"abstract":"<div><p>Piano key weirs (PKWs) are a new, nonlinear form of labyrinth weir known for their high hydraulic efficiency. Investigating local scour and developing solutions to mitigate it for these weirs is of significant importance. In the present research, for the first time and to the best of our knowledge, edged steps were implemented in the outlet keys of a Type B trapezoidal PKW. The PKW model used had a height of 0.20 m and consisted of three cycles. The steps, configured in sets of four per outlet key, were installed with three different edge heights and two different longitudinal positions within each key. Edged steps direct the flow and maximum scour depth further away from the weir toe. The edges act as a barrier, reducing the flow velocity exiting the outlet keys. By relocating the maximum scour to a greater distance from the weir toe, the risk of structural undermining is lessened. As the edge height increases, the maximum scour depth decreases, and its location moves farther downstream. The presence of edges at the end of the steps contributes significantly to scour reduction. Edged steps showed better performance in reducing scour compared to un-edged weirs. Furthermore, the maximum scour depth decreases with a reduction in the densimetric Froude number, which is achieved by lowering the flow discharge or increasing the tailwater depth. In the present study, the densimetric Froude number ranged from 0.437 to 0.887. Finally, dimensional analysis and gene expression programming (GEP) were employed to derive predictive equations for the maximum scour depth and its corresponding distance from the weir toe.</p></div>","PeriodicalId":6988,"journal":{"name":"Acta Geophysica","volume":"74 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147607104","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}

引用次数: 0

Effects of the Storm Daniel on the environmental radiological map of Thessaly 风暴丹尼尔对色萨利环境辐射图的影响

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-03-30 DOI: 10.1007/s11600-026-01857-w

Ioannis Kaissas, Parashos Toulgaridis

{"title":"Effects of the Storm Daniel on the environmental radiological map of Thessaly","authors":"Ioannis Kaissas, Parashos Toulgaridis","doi":"10.1007/s11600-026-01857-w","DOIUrl":"10.1007/s11600-026-01857-w","url":null,"abstract":"<div><p>Thessaly includes one of Greece’s largest plains and the watershed of Pindus Mountain range and thus is particularly susceptible to flooding. Storm Daniel caused extensive floodings in Thessaly basins, in September 2023. Significant agricultural productivity, along with relevant industrial activity, takes place in Thessaly; therefore, such intensive climate change phenomena affect not only the topical ecosystem but the national economy. In this work, Thessaly was divided into six sectors, to investigate the changes in the environmental radioactivity map caused by the Storm Daniel. Samples were collected from flooded and not-flooded locations in each sector. γ-Spectroscopy was performed on the samples with a high-purity germanium detector. The results for all the sectors show Cs-137 concentrations in the flooded areas lower than the ones in the not-flooded areas. Specifically, the mean concentration of Cs-137 in flooded and not-flooded areas is 4.6 Bq/kg and 38.8 Bq/kg, respectively. The concentrations of the other radionuclides vary across the sampled sectors, indicating the influence of flood events on the distribution of the NORM radionuclides in the soil. Remarkable differences are observed only in flooded and not-flooded areas for U-238 and Ra-226. The mean concentrations of U-238 are 18.6 Bq/kg and 24.7 Bq/kg, and the mean concentrations of Ra-226 are 21.1 Bq/kg and 28.5 Bq/kg, respectively. The uncertainty of the measurements is approximately 17% for U-238 and about 6% for all the other radionuclides. The findings contribute to the understanding of the environmental impact of floods, particularly in regions with significant agricultural and ecological value. This work suggests that floods can alter the radionuclide profile of soils. Additionally, it highlights the need for ongoing monitoring and further research to assess the long-term effects of flooding on radiological maps and the broader implications for the environment and public health.</p></div>","PeriodicalId":6988,"journal":{"name":"Acta Geophysica","volume":"74 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11600-026-01857-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147607106","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}

引用次数: 0

The legacy and implications of cyberinfrastructure systems in hydrological process modeling 网络基础设施系统在水文过程建模中的遗留问题和影响

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-03-29 DOI: 10.1007/s11600-026-01852-1

Zaher Mundher Yaseen

引用次数: 0

Dry and wet periods in north-central Poland in the years 1952–2020 1952-2020年波兰中北部的干湿期

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-03-28 DOI: 10.1007/s11600-026-01854-z

Arkadiusz Bartczak, Zbigniew Podgórski, Andrzej Araźny, Halina Kaczmarek, Sebastian Tyszkowski

{"title":"Dry and wet periods in north-central Poland in the years 1952–2020","authors":"Arkadiusz Bartczak, Zbigniew Podgórski, Andrzej Araźny, Halina Kaczmarek, Sebastian Tyszkowski","doi":"10.1007/s11600-026-01854-z","DOIUrl":"10.1007/s11600-026-01854-z","url":null,"abstract":"<div><p>The study investigates correlations between atmospheric circulation, precipitation, potential evaporation, Climatic Water Balance (CWB), and river runoff in north-central Poland and quantifies the occurrence of dry and wet periods. The analysis covers the years 1952–2020. Dry and wet periods were identified using monthly Standardised Streamflow Indices (SSI) calculated for moving windows of 1, 3, 6, and 12 months (SSI-1, SSI-3, SSI-6, SSI-12). The study also employs a unique calendar of circulation types over north-central Poland, from which atmospheric circulation indices were calculated: zonal (W), meridional (S), and cyclonicity (C). The results show that, in north-central Poland during 1952–2020, the annual totals of potential evaporation and Climatic Water Balance (CWB) both exhibited statistically significant trends. The rate of change was + 27.8 mm per decade for potential evaporation and − 29.6 mm per decade for CWB. The annual precipitation totals did not display a statistically significant trend. The analysis revealed a significant correlation between the cyclonicity index (C) and the Standardised Streamflow Index (SSI) for all the analysed rivers and moving windows. Dry periods occurred under strong anticyclonic circulation, whereas wet periods were associated with the dominance of cyclonic circulation. Additionally, the correlation coefficients between precipitation and SSI, potential evaporation and SSI, and CWB and SSI were statistically significant across all moving windows. The value of the correlation coefficient was lowest for SSI-1 and highest for SSI-12, reflecting the influence of seasonal variability in the annual cycles of the analysed climatic and hydrological elements within the study area.</p></div>","PeriodicalId":6988,"journal":{"name":"Acta Geophysica","volume":"74 2","pages":""},"PeriodicalIF":2.1,"publicationDate":"2026-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147561910","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}

引用次数: 0

Correction: Application of beveled submerged vanes for controlling erosion of the outer bank of Ganga river at Bhagalpur, India 更正：坡面淹没叶片在印度巴加尔布尔恒河外岸控制侵蚀的应用

IF 2.1 4区地球科学

Acta Geophysica Pub Date : 2026-03-28 DOI: 10.1007/s11600-026-01861-0

Anirban Mandal, Subhojit Kadia, Zulfequar Ahmad

引用次数: 0