{"title":"Predictive model for peak ground velocity using long short-term memory networks","authors":"Dongwang Tao, Haifeng Zhang, Shanyou Li, Jianqi Lu, Zhinan Xie, Qiang Ma","doi":"10.1007/s10950-024-10268-7","DOIUrl":"10.1007/s10950-024-10268-7","url":null,"abstract":"<div><p>Peak ground velocity (PGV) is a crucial ground motion parameter correlating with earthquake damage. How to quickly predict PGV at a target site is a core issue of earthquake early warning (EEW) system. By using the embedded characteristics in ground motion sequence, a Long Short-Term Memory (LSTM) networks-based onsite PGV prediction model (LSTM-PGV) is proposed in this paper. The LSTM-PGV model consists of three layer of LSTM and one fully connected layer, and the inputs are sequence features of energy-related, amplitude-related, period-related and distance-related P-wave parameters. The performance of the LSTM model on training, validation and test datasets indicates that the model has good generalization capability, and the predicted PGV and observed PGV can meet the 1:1 relationship in general. Compared with Pd-PGV model, a logarithmic linear regression model where Pd is the peak vertical displacement of the first 3 s P-waves, and LSTM-Pd-PGV model, a LSTM-based model with Pd as the sole input sequency feature where Pd is the maximum vertical displacement continuously changing over time, the proposed model predicts PGV more accurately and stably. Furthermore, the issue of underestimation of PGV for larger earthquakes is alleviated in LSTM-PGV model by using longer length of sequence input. The LSTM model is tested with one off-shore earthquake and one inland earthquake in Japan. The results show that the standard deviation of prediction residual goes from 0.417 at sequence length of 3 s to 0.309 at sequence length of 10 s for the off-shore event, and for the inland event the standard deviation decreases from 0.357 to 0.267 at corresponding sequence length. The prediction timeliness measured by lead time, defined as the time interval between the moment when the observed PGV reaches 17.3 cm/s and the moment when the predicted PGV reaches the same threshold, is also discussed for different magnitudes and hypocentral distances. We believe the proposed LSTM model has promising potential in onsite EEW system for providing accurate and timely PGV prediction.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"221 - 240"},"PeriodicalIF":1.6,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688297","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":"Deep learning based earthquake and vehicle detection algorithm","authors":"Deniz Ertuncay, Andrea de Lorenzo, Giovanni Costa","doi":"10.1007/s10950-024-10267-8","DOIUrl":"10.1007/s10950-024-10267-8","url":null,"abstract":"<div><p>Seismic recorders register vibrations from all possible sources. Even though the purpose of the seismic instrument is, usually, to record ground motions coming from tectonic sources, other sources such as vehicles can be recorded. In this study, a machine learning model is developed by using a convolutional neural network (CNN) to separate three different classes which are earthquakes, vehicles, and other noises. To do that vehicle signals from various accelerometric stations from Italy are visually detected. Together with the vehicle signals noise and earthquake information coming from Italy are used. Inputs of the database are 10 s long seismic traces along with their frequency content from three channels of the seismic recorder. CNN model has an accuracy rate of more than 99 % for all classes. To understand the capabilities of the model, seismic traces with vehicles and earthquakes are given as input to the model which the model successfully separates different classes. In the case of the superposition of an earthquake and a vehicle, the model prediction is in favor of the earthquake. Moreover, earthquake signals from various databases are predicted with more than 90 % accuracy.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"269 - 281"},"PeriodicalIF":1.6,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10950-024-10267-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688261","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}
Qi Zhang, Ruyu Cui, Hao Huang, Ming Zhao, Jingyang Tan
{"title":"Ground motion prediction model for significant duration of horizontal component based on the K-NET database","authors":"Qi Zhang, Ruyu Cui, Hao Huang, Ming Zhao, Jingyang Tan","doi":"10.1007/s10950-024-10265-w","DOIUrl":"10.1007/s10950-024-10265-w","url":null,"abstract":"<p>The duration of strong ground motion has a significant impact on the nonlinear seismic behavior of engineering systems. This article presents a prediction model for the significant duration of horizontal ground motion as a function of magnitude, hypocenter distance, and site condition. Based on 7111 records of shallow crustal earthquakes from the K-NET Database, the model functional forms for each term (magnitude, distance, and site condition) are selected carefully to improve the model adaptability to data, and an additional constraint is applied to prevent overfitting of magnitude dependency at near-fields for large earthquakes. Compared to other models, the proposed model demonstrates a weaker dependency of significant duration on magnitude at near fields, especially for large earthquakes. The significant duration decreases with increasing <i>V</i><sub><i>s</i>30</sub> at soft sites but at hard sites with <i>V</i><sub><i>s30</i></sub> exceeding 300 m/s or so, the significant duration is independent of <i>V</i><sub><i>s</i>30</sub>.</p>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"187 - 198"},"PeriodicalIF":1.6,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688606","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":"Seismic hazard mapping for peak ground velocity: microzonation of Novi Sad, Serbia—a case study in a low-seismicity region exposed to large and distant earthquakes","authors":"V. W. Lee, M. D. Trifunac, B. Đ. Bulajić","doi":"10.1007/s10950-024-10259-8","DOIUrl":"10.1007/s10950-024-10259-8","url":null,"abstract":"<div><p>We introduce a new form of probabilistic seismic microzonation maps in terms of <span>({V}_{text{max}})</span> peak velocity of strong earthquake ground motion and illustrate the method for the city of Novi Sad in Serbia. The maps we introduce avoid the limitations of hazard maps drawn solely on peak ground acceleration, which are physically limited to one-parameter scaling The new method complements seismic hazard maps based on Uniform Hazard Spectra (UHS) by directly scaling several characteristics of strong motion that cannot be physically related to spectral amplitudes or to peak accelerations. We demonstrate how the new maps can be used to evaluate strains near ground surface during strong ground motion, as well as areas where buildings can be damaged during future strong ground motion. The new microzonation maps of <span>({V}_{text{max}})</span>, together with probabilistic estimates of relative displacement (SD) spectra, can be used to derive estimates of pseudo-static forces in ground-level columns of long structures.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"85 - 105"},"PeriodicalIF":1.6,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688289","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}
Caglar Temiz, S. M. Sajad Hussaini, Shaghayegh Karimzadeh, Aysegul Askan, Paulo B. Lourenço
{"title":"Seismic scenario simulation and ANN-based ground motion model development on the North Tabriz Fault in Northwest Iran","authors":"Caglar Temiz, S. M. Sajad Hussaini, Shaghayegh Karimzadeh, Aysegul Askan, Paulo B. Lourenço","doi":"10.1007/s10950-024-10264-x","DOIUrl":"10.1007/s10950-024-10264-x","url":null,"abstract":"<div><p>Earthquakes pose significant seismic hazards in urban regions, often causing extensive damage to the built environment. In regions lacking robust seismic monitoring networks or sufficient data from historical events, ground motion simulations are crucial for assessing potential earthquake impacts. Yet, validating these simulations is challenging, leading to notable predictive uncertainty. This study aims to simulate four scenario earthquakes with moment magnitudes of 6.8, 7.1, 7.4, and 7.7 in Iran, specifically investigating variations in fault plane rupture and earthquake hypocenter. The North Tabriz Fault (NTF), located within the seismic gap in northwest Iran, is selected as the case study due to the lack of well-recorded ground motions from severe earthquakes, despite historical evidence of large-magnitude events. Simulations are conducted using a stochastic finite-fault ground motion simulation methodology with a dynamic corner frequency. Validation of the simulations is performed by comparing estimated peak ground motions and pseudo-spectral ordinates with existing ground motion models (GMMs), supplemented by inter-period correlation analysis. Simulation results reveal high hazard levels, especially in the northeastern area near the fault plane. Intensity maps in terms of the Modified Mercalli Intensity (MMI) scale underscore the urgency for comprehensive preparedness measures. Finally, a region-specific GMM is developed using Artificial Neural Networks (ANN) to predict peak ground motion parameters with an online platform accessible to end-users.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"147 - 169"},"PeriodicalIF":1.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10950-024-10264-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688470","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":"Multi-scale convolution networks for seismic event classification with windowed self-attention","authors":"Yongming Huang, Yi Xie, Wei Liu, Yongsheng Ma, Fajun Miao, Guobao Zhang","doi":"10.1007/s10950-024-10262-z","DOIUrl":"10.1007/s10950-024-10262-z","url":null,"abstract":"<div><p>The classification of seismic events is important for earthquake emergency warnings and earthquake catalog database establishment. In this paper, we developed a multiscale convolution and window self-attention network for seismic event classification by combining multiscale convolution with inductive bias capability and self-attention mechanism with long-range information capture capability. This paper employed a pre-processing strategy to acquire the complete seismic waveform and separate seismic data in each component. Additionally, a voting mechanism is proposed to integrate data from three components for classification, improving overall accuracy. The experimental results showed that the overall classification accuracy is 94.02% when considering seismic data from a single component only. However, after incorporating a voting mechanism, the classification accuracy increases to 97.56%, which outperforms other methods. The results demonstrated that the multi-scale convolutional and windowed self-attention networks can effectively and significantly improve the accuracy of seismic event classification, which get a good result in seismic event classification.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"257 - 268"},"PeriodicalIF":1.6,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688321","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":"S-wave velocity structure beneath the eastern part of the Qinhang metallogenic belt and its adjacent areas","authors":"Meng Gong, Bingyue Liu, Juzhi Deng, Ke Xu, Yingchun Zhang, Jian Lü","doi":"10.1007/s10950-024-10261-0","DOIUrl":"10.1007/s10950-024-10261-0","url":null,"abstract":"<div><p>To further understand the structure of the Qinhang Metallogenic Belt (QHMB) and its adjacent areas in the southeastern region of China, we collected continuous waveform data from 73 broadband stations recorded from 1th January to December 31th 2021, and applied ambient noise tomography method to obtain the 3D S-wave velocity structure from the surface to the depths of 45 km in the area. We used the time–frequency normalization (FTAN) approach to extract 2035 phase velocity dispersion curves, and applied the Occam inversion algorithm to generate the phase velocity maps of 5 ~ 45 s. After that, we utilized the surf96 program to invert the 1D velocity structure of the S-wave under each grid, and then combined these grid points to produce a high-resolution 3D structure of the S-wave velocity structure. Based on the inversion results, we draw the conclusions as follows: (1) The high-speed body appearing in the middle crust below the Qinling Dabie Orogenic Belt (QDOB) may be the consequence of the direct cooling of partially melted magma formed by the upwelling of asthenosphere material into the middle and lower crust; (2) Since the Late Mesozoic, the subsidence of the lower crust and large-scale basal magma intrusion have caused a northeast-southwest trending high-speed band-shaped anomaly in the middle-lower crust of the area; (3) Against the background of continental extension, the thickening and extension of the crust have led to the enrichment of mineral-rich upwelling in suitable locations, ultimately forming the present-day metallogenic belts in the Middle-Lower Yangtze River Metallogenic Belt (MLYMB) and the eastern of the QHMB.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"31 - 45"},"PeriodicalIF":1.6,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688320","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":"The high-frequency decay parameter Kappa (κ) in the Alborz Region using broadband seismic waveforms","authors":"Somayeh Ahmadzadeh, Gholam Javan-Doloei","doi":"10.1007/s10950-024-10256-x","DOIUrl":"10.1007/s10950-024-10256-x","url":null,"abstract":"<div><p>The high-frequency decay parameter (κ) is investigated using the three-component broadband seismograms from 306 earthquakes with M<sub>L</sub> 3.1–5.6 recorded at nine Iranian National Broadband Seismic Network (BIN) stations in the Alborz region and adjacent areas. The individual κ values are calculated for both the horizontal and vertical components of each record. The estimated mean horizontal and vertical κ values are 0.051 and 0.035 s, respectively, indicating slightly lower attenuation of high-frequency energy on the vertical component than the horizontal one. The dependence of the kappa values on path and source parameters such as distance, magnitude, and focal mechanism are also investigated. A clear increasing trend is observed for κ values with hypocentral distances for horizontal and vertical components. The zero-distance kappa (κ<sub>0</sub>) values for the nine BIN stations are evaluated, and a mean value of 0.013 s is estimated, which is close to the values expected for generic rock sites. The obtained κ values show no significant correlation with the earthquake size in the magnitude range of our events. Furthermore, the κ values are found to be fairly similar for all faulting types, with a slight decrease in κ for strike-slip events; hence, the kappa values are deemed as independent of faulting type.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 6","pages":"1471 - 1488"},"PeriodicalIF":1.6,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941289","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":"GSBBO: a high-precision method for stress tensor inversion and its application at the great wall station in Antarctica","authors":"Zhaoxuan Guan, Yongge Wan, Mingyue Zhou, Shaohua Huang","doi":"10.1007/s10950-024-10260-1","DOIUrl":"10.1007/s10950-024-10260-1","url":null,"abstract":"<div><p>The current stress tensor inversion method based on the focal mechanism cannot solve problems such as the interference of too many outliers on the results and the slow speed and low accuracy caused by the excessive computation of the inversion process; therefore, we propose a new stress tensor inversion method, GSBBO (grid search, boxplot and Bayesian optimization), which combines machine learning algorithms to sieve out outlier data and improve the inversion speed and accuracy. The method first screens the focal mechanism data via a grid search and boxplot, and this process eliminates the bias of the outliers on the results. Then, to improve the speed and accuracy of the inversion results, the method further inverts the stress tensor by means of Bayesian optimization, which can obtain high-precision results quickly by means of screened datasets and machine learning algorithms. The GSBBO method is validated using artificially synthesized focal mechanism data containing random noise and outliers for three stress systems. The obtained results are compared with those of grid search and Bayesian optimization, and the GSBBO method is able to accurately identify the outliers and provide more accurate results quickly. Applying the method to the area of the Great Wall Station in Antarctica, the results show that the area experiences near-vertical compressive stress and strong northwest‒southeast extensional stress, which is consistent with the extensional stress in the area due to the subsidence of the Phoenix Plate. These findings indicate the continuing subsidence process of the Phoenix Plate in Antarctica.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"5 - 19"},"PeriodicalIF":1.6,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688448","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":"Impact of ({{varvec{M}}}_{{varvec{W}}}) definition approach on Fourier ground-motion variability of shallow crustal earthquakes in Europe","authors":"Aurore Laurendeau, Sreeram Reddy Kotha","doi":"10.1007/s10950-024-10254-z","DOIUrl":"10.1007/s10950-024-10254-z","url":null,"abstract":"<div><p>A Ground-Motion Model (GMM)'s apparent aleatory variability is inflated by errors in its predictor parameters, specifically the moment magnitude (<span>({M}_{W})</span>). Multiple <span>({M}_{W})</span> values can be available for an event (direct or deduced) and various <span>({M}_{W})</span> definition approaches have been proposed to assign a unique <span>({M}_{W})</span> value to an event. In this study, we investigate the impact of <span>({M}_{W})</span> definition on a pan-European Engineering Strong Motion dataset based Fourier GMM, using two datasets with <span>({M}_{W})</span> defined by two distinct approaches: [1] the ranking strategy of the Euro-Mediterranean Earthquake Catalogue (EMEC 2019) and [2] the multi-strategy (standardization, ranking, unification, averaging) approach to <span>({M}_{W})</span> definition of Laurendeau et al., (Geophys J Int 230:1980–2002, 2022). Large discrepancies in <span>({M}_{W})</span> values can be observed especially between <span>({M}_{W})</span> ranging from 4.0 to 5.0. While the GMM median predictions remain unchanged irrespective of dataset, we report a large reduction in between-event variability of the GMM at low frequencies (< 1.8 Hz) when strategy [2] is adopted over [1] (18% at 0.35 Hz). This reduction applies to frequencies before the corner-frequency of the Fourier spectrum, as this part of the spectrum depends primarily on seismic moment. We attribute this reduction to the use of direct <span>({M}_{W})</span> values in [2] instead of deduced <span>({M}_{W})</span> values in [1], the priority scheme in the ranking strategy, and the unification strategy. Our study suggests that the approach used to define a unique <span>({M}_{W})</span> in the GMM dataset may have a significant impact on its predictions in seismic hazard assessment.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"29 1","pages":"127 - 145"},"PeriodicalIF":1.6,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688449","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}