Journal of Seismology最新文献

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Multimodal quantitative segmental analysis of seismicity of the Zhangjiakou-Bohai tectonic belt (North China) 张家口-渤海构造带(华北)地震多模态定量分段分析
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-08-02 DOI: 10.1007/s10950-024-10234-3
Jinmeng Bi, Cheng Song, Fuyang Cao, Yong Ma
{"title":"Multimodal quantitative segmental analysis of seismicity of the Zhangjiakou-Bohai tectonic belt (North China)","authors":"Jinmeng Bi,&nbsp;Cheng Song,&nbsp;Fuyang Cao,&nbsp;Yong Ma","doi":"10.1007/s10950-024-10234-3","DOIUrl":"10.1007/s10950-024-10234-3","url":null,"abstract":"<div><p>The purpose of this study is to systematically investigate the segmental seismicity features of the Zhangjiakou-Bohai tectonic belt to understand the characteristics of the seismic activity in this tectonic area and identify potential sources of strong earthquake hazard. From the collected seismic data, we first determined the minimum completeness magnitude by combining qualitative and quantitative methods, such as the detection rate function, maximum curvature (MAXC) method, goodness of fit (GFT) method and magnitude-rank method. We used the stochastic declustering method based on the space-time ETAS model to obtain the background seismicity. We then implemented the accelerating moment release (AMR) model, the Ogata-Katsura 1993 (OK1993) model, the moment ratio (MR) model and the Region-Time-Length (RTL) algorithm. Finally, we analyzed the spatial migration of strong earthquakes. The completeness magnitude of the earthquake sequence does not significantly change with time, with the minimum completeness magnitude being 2.0 for the Zhangjiakou-Bohai tectonic zone. The results provided by the aforementioned seismic activity models allow us to detect some differences between sectors of the tectonic belt. The Zhangjiakou and Tangshan segments show a higher level of seismic hazard compared to the others, which have little chance of a strong earthquake occurring (weak release of seismic energy). The <i>b</i> value of the Zhangjiakou segment shows a stepwise downward trend, reflecting the gradual increase of stress accumulation level, and the hazard of moderate-strong earthquakes is increasing. Compared with the Tangshan and Penglai segments, the Zhangjiakou and Beijing sectors have a slightly higher MR index, which means that the rate of earthquake occurrence is increasing and thus the hazard of moderate to strong earthquakes. According to the RTL value, the deviation of seismic activity in the Zhangjiakou and Tangshan segments is relatively high, and there is a possibility of moderate to strong earthquakes in the future. Based on the results obtained from various seismicity models and the migration law of strong earthquakes, we can say that the overall seismic hazard for each sector of the Zhangjiakou-Bohai tectonic chain is low in terms of qualitative analysis. If anything, the Zhangjiakou segment, which is the section with the relatively high seismic hazard level, should require our attention in the future.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 5","pages":"1309 - 1323"},"PeriodicalIF":1.6,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141881370","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
Numerical simulation of near-fault ground strains and rotations from actual earthquakes with predominantly dip-slip mechanisms 以数值模拟以倾滑机制为主的实际地震产生的近断层地层应变和旋转
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-07-29 DOI: 10.1007/s10950-024-10230-7
Yenan Cao, George P. Mavroeidis
{"title":"Numerical simulation of near-fault ground strains and rotations from actual earthquakes with predominantly dip-slip mechanisms","authors":"Yenan Cao,&nbsp;George P. Mavroeidis","doi":"10.1007/s10950-024-10230-7","DOIUrl":"10.1007/s10950-024-10230-7","url":null,"abstract":"<div><p>In the absence of records of near-fault ground strains and rotations from strong earthquakes, deterministic physics-based simulations have become an important tool for characterizing these motions in the low-frequency range (e.g., &lt; 1.0 Hz). Building on a previous study of near-fault ground strains and rotations from actual strike-slip ruptures conducted by the authors, this article investigates the spatial and temporal characteristics of such motions generated by actual earthquakes with predominantly dip-slip mechanisms. This is achieved by performing forward ground-motion simulations of the 1994 <i>M</i><sub>w</sub> 6.7 Northridge, the 1989 <i>M</i><sub>w</sub> 6.9 Loma Prieta, and the 1985 <i>M</i><sub>w</sub> 8.1 Michoacan earthquakes using previously published finite-fault rupture models. For each considered seismic event, time histories of ground strains and rotations are generated at near-fault recording stations and at a dense grid of observation points. This is accomplished by finite differencing translational motions simulated at very closely spaced stations using a kinematic modeling approach. The simulation results show large-amplitude axial strain, shear strain, and rocking in the near-fault region. For the considered earthquakes, the maximum peak ground strain over all grid points is of the order of ~ 100–250 <i>μ</i>strain, whereas the maximum peak ground rocking ranges from ~ 100 to ~ 200 <i>μ</i>rad. The attenuation characteristics of peak ground strains and rotations differ for the considered seismic events and depend on the component of interest and the rupture distance. Finally, peak ground rocking can be reasonably estimated from peak vertical ground velocity using a properly selected scaling factor despite the significant variability of the latter in the near-fault region. Filtering out the very low frequencies of ground motion (&lt; 0.1 Hz), including the static offset, significantly affects the scaling factor.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 4","pages":"1027 - 1053"},"PeriodicalIF":1.6,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865107","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
Characterization of seismic b-value around kopili fault and its neighboring region prior to 28th April 2021 earthquake 2021 年 4 月 28 日地震前科皮里断层及其邻近地区的地震 b 值特征
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-07-20 DOI: 10.1007/s10950-024-10232-5
Vickey Sharma, Dipok Kumar Bora, Devajit Hazarika, Rajib Biswas
{"title":"Characterization of seismic b-value around kopili fault and its neighboring region prior to 28th April 2021 earthquake","authors":"Vickey Sharma,&nbsp;Dipok Kumar Bora,&nbsp;Devajit Hazarika,&nbsp;Rajib Biswas","doi":"10.1007/s10950-024-10232-5","DOIUrl":"10.1007/s10950-024-10232-5","url":null,"abstract":"<div><p>In the present study, the spatio-temporal variation of the seismic b-value in the vicinity of the Kopili fault and its surrounding area has been analysed using the unified and homogenous earthquake catalog of historical and instrumental (1950–2021) earthquake events. The study region is subdivided into 16 equisized square grids of 1° × 1° dimension, and the b-value is computed for each grid using the maximum likelihood method. The spatial distribution of the b-value varies from 0.58 to 1.14. The Kolmogorov–Smirnov (K-S) test has been conducted to check the significance of the spatial-temporal and depth-wise distributions of the b-value. The epicentral location of April 28th, 2021, lies in the low-b-value square grid. Likewise, the temporal b-value curve shows a decreasing trend before the occurrence of the April 28th, 2021 earthquake. The mean return period of the April 28th, 2021earthquake and the most probable maximum annual magnitude earthquake are also computed for this region. Meanwhile, the spatial associations and anomalous patterns between the b-value and factors like seismic moment or energy release and focal depth are assessed, as they contribute to a more comprehensive understanding of the seismicity in this area. The antithetical relationship between the b-value and seismic moment or energy release is established. While variation in b-value with depth provides new insights, low b-values are linked to the top of the crust, which could mean that the crust is uniform and that a lot of stress is building up.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 4","pages":"1001 - 1025"},"PeriodicalIF":1.6,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141746105","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
Revisiting Stepp’s method for the completeness of regional seismic catalogues 重新审视斯泰普的区域地震目录完整性方法
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-07-18 DOI: 10.1007/s10950-024-10231-6
Narsiram Gurjar, Dhiman Basu
{"title":"Revisiting Stepp’s method for the completeness of regional seismic catalogues","authors":"Narsiram Gurjar,&nbsp;Dhiman Basu","doi":"10.1007/s10950-024-10231-6","DOIUrl":"10.1007/s10950-024-10231-6","url":null,"abstract":"<div><p>An important step in seismic hazard analysis is investigating the completeness of available data. Out of the various methods proposed by several researchers, Stepp’s method is one of the most commonly used methods for completeness analysis. Some drawbacks are identified in this method, which results in erroneous estimation of the completeness period. This paper suggests another way of estimation based on the 2-point moving average of the mean annual rate of occurrence of events. The new procedure is able to overcome the problems identified in Stepp’s method and is validated using five catalogues from different regions. The analysis result includes the completeness period determination for different catalogues before and after correction, together with Magnitude-Frequency recurrence relation coefficients compared with Stepp’s method.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 4","pages":"1055 - 1086"},"PeriodicalIF":1.6,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141746106","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
Comparison between rupture parameters of intermediate and deep earthquakes at the Peru–Brazil–Bolivia border and northern Chile 秘鲁-巴西-玻利维亚边境和智利北部中深层地震破裂参数的比较
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-07-09 DOI: 10.1007/s10950-024-10229-0
Carmen Pro, Hernando Tavera, Maurizio Mattesini, Lucía Escudero, Elisa Buforn, Agustín Udías, Estela Centeno
{"title":"Comparison between rupture parameters of intermediate and deep earthquakes at the Peru–Brazil–Bolivia border and northern Chile","authors":"Carmen Pro,&nbsp;Hernando Tavera,&nbsp;Maurizio Mattesini,&nbsp;Lucía Escudero,&nbsp;Elisa Buforn,&nbsp;Agustín Udías,&nbsp;Estela Centeno","doi":"10.1007/s10950-024-10229-0","DOIUrl":"10.1007/s10950-024-10229-0","url":null,"abstract":"<div><p>We determined the main parameters of the source rupture process of intermediate- and deep-depth earthquakes occurring in the Peru–Brazil–Bolivia border region and northern Chile. The parameters of depth, fault-plane orientation, scalar seismic moment, slip distribution, and radiated seismic energy are obtained from seismograms. We selected 15 intermediate-depth earthquakes (100 km &lt; h &lt; 300 km) and 10 very deep earthquakes (h &gt; 500 km) with magnitudes M<sub>W</sub> ≥ 6.0. For most events, the slip distribution over the rupture plane shows a single asperity, and the source time function presents a simple pulse. There are differences between intermediate-depth and deep earthquakes. The rupture areas, maximum slip and source time function (STF) duration are larger for intermediate-depth events than for deep events. Additionally, the STF’s show a sharper increase for deep earthquakes. The scaled radiated seismic energy shows larger values for deep depth events. The stress regime pattern derived from the obtained focal mechanism agrees with the geometry of the subduction of the Nazca plate. At intermediate depths, in the northern area up to 12°S, the stress pattern corresponds to a horizontal extension, while in the southern area, the tension axes dip at an angle of 30°. At deep depths, the stress regime corresponds to vertical compression in the north and dips of approximately 45° in the south.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 4","pages":"973 - 999"},"PeriodicalIF":1.6,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10950-024-10229-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141570109","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
Spatiotemporal properties of the 2020 – 2021 Petrinja (Croatia) earthquake sequence 2020 - 2021 年佩特里尼亚(克罗地亚)地震序列的时空特性
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-07-01 DOI: 10.1007/s10950-024-10228-1
Eirini Sardeli, Georgios Michas, Kyriaki Pavlou, Davide Zaccagnino, Filippos Vallianatos
{"title":"Spatiotemporal properties of the 2020 – 2021 Petrinja (Croatia) earthquake sequence","authors":"Eirini Sardeli,&nbsp;Georgios Michas,&nbsp;Kyriaki Pavlou,&nbsp;Davide Zaccagnino,&nbsp;Filippos Vallianatos","doi":"10.1007/s10950-024-10228-1","DOIUrl":"10.1007/s10950-024-10228-1","url":null,"abstract":"<div><p>The Petrinja earthquake sequence started on December 28, 2020, with a destructive <i>M</i><sub><i>L</i></sub> 6.2 mainshock occurring in the area, preceded by a <i>M</i><sub><i>L</i></sub> 5.08 foreshock, following a long period of relative seismic quiescence. Over the first six months of the Petrinja earthquake sequence, almost 14,000 events were recorded. In the present work, we separated seismic events based on their spatial concentration using a density-based clustering algorithm, DBSCAN. We identified four main clusters and analyzed their spatiotemporal properties using the notions of Non-Extensive Statistical Physics (NESP). This framework, which relies on Tsallis entropy (<i>S</i><sub><i>q</i></sub>), describes the scaling behavior of complex systems. In this frame, we investigated the inter-event time (<i>T</i>) and distance (<i>D</i>) distributions, providing the <i>q</i><sub><i>T</i></sub> and <i>q</i><sub><i>D</i></sub> entropic parameters, respectively. Additionally, we studied the frequency–magnitude distributions in terms of the fragment–asperity model, leading to the determination of the non-extensive parameter <i>q</i><sub><i>M</i></sub>. The results of the analysis suggest that the statistical properties of the Petrinja earthquake sequence can be effectively reproduced utilizing NESP. Furthermore, the coseismic static Coulomb stress changes were estimated, indicating that the clusters’ seismic events may have resulted from a complex fault system's (re)activation. In addition, the effective static stress drop was estimated for each spatial cluster. Lastly, the temporal patterns of the earthquake evolution are discussed using the superstatistics approach, indicating that the temporal progression of the Petrinja earthquake clusters is governed by a very low number of degrees of freedom, highlighting the spatiotemporal organization of each cluster.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 4","pages":"899 - 920"},"PeriodicalIF":1.6,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507400","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
Reevaluating soil amplification using multi-spectral HVSR technique in La Chana Neighborhood, Granada, Spain 利用多光谱 HVSR 技术重新评估西班牙格拉纳达 La Chana 社区的土壤放大情况
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-06-26 DOI: 10.1007/s10950-024-10227-2
Carlos Jose Araque-Perez
{"title":"Reevaluating soil amplification using multi-spectral HVSR technique in La Chana Neighborhood, Granada, Spain","authors":"Carlos Jose Araque-Perez","doi":"10.1007/s10950-024-10227-2","DOIUrl":"10.1007/s10950-024-10227-2","url":null,"abstract":"<div><p>This work presents a thorough reevaluation of soil amplification in the La Chana neighborhood of Granada through a pioneering application of the horizontal-to-vertical spectral ratio technique on seismic noise data using various spectral approaches. The research recycles old seismic noise data recorded at 34 stations with 2 Hz instruments in the year 2010, supplemented with additional measurements recorded with broadband seismometers at nearby locations in the years 2013 and 2017. Initial traditional processing identifies a narrowband dominant frequency around 1.5 Hz, attributed to artificial or anthropogenic sources. To address this, the Maximum Entropy Algorithm was implemented to smooth the spectral response below 1 Hz, and filter out frequency peaks with very narrow spectral bands, while preserving the narrowband frequency around 1.5 Hz in some records. The Thomson Multitaper method further refined the spectral ratio, emphasizing the detection and suppression of narrow frequency bands that may be related to industrial activity. The results demonstrated the reappearance of the 1.5 Hz frequency, but this time without narrow bandwidths, indicating its possible correlation with the natural ground movement. Fundamental periods, ranging from 0.45 s to 0.88 s, suggest a diverse lithological composition, indicating the presence of layers of sands, clays, conglomerates, and carbonates over a basement that represents the main impedance contrast in the area. The multispectral approach surpasses conventional methods in precision and reliability, providing valuable insights for earthquake risk assessment, urban planning, and engineering decisions in seismically active regions.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 4","pages":"921 - 949"},"PeriodicalIF":1.6,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10950-024-10227-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507401","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
Directivity analysis and source parameter estimation: insights from the 2014 Arzew earthquake, Mw3.9, northwestern Algeria 指向性分析和震源参数估计:2014 年阿尔及利亚西北部阿尔泽夫 Mw3.9 地震的启示
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-06-25 DOI: 10.1007/s10950-024-10226-3
Oualid Boulahia, Fethi Semmane
{"title":"Directivity analysis and source parameter estimation: insights from the 2014 Arzew earthquake, Mw3.9, northwestern Algeria","authors":"Oualid Boulahia,&nbsp;Fethi Semmane","doi":"10.1007/s10950-024-10226-3","DOIUrl":"10.1007/s10950-024-10226-3","url":null,"abstract":"<div><p>The March 20, 2014, magnitude M<sub>w</sub>3.9 earthquake near Arzew, Algeria, instigated a study to deepen comprehension of seismic activity and hazard in the region. Analyzing data from Algerian and Spanish seismic networks, we explored earthquake characteristics and rupture mechanisms. The earthquake's epicenter was located at 35.825° latitude and -0.366° longitude, with a depth of 7 km, exhibiting intensity IV-V in the Arzew-Oran area. Preceding this event, a magnitude M<sub>D</sub>3.1 foreshock occurred on February 1, 2014, at the same location. The waveforms of the foreshock and mainshock exhibited striking similarities, validating the effectiveness of the Empirical Green's Function method employed for deconvolution. Through waveform inversion and P-wave polarities, we estimated the focal mechanism, revealing a near-pure strike-slip mechanism with nodal planes oriented ~E-W and ~N-S. The rupture process, characterized by multiple episodes, propagated predominantly from the south towards the N5°-15°E direction at a velocity around 2.7 km/s along an 870 m fault length in 0.32 seconds. The mainshock's fault plane was identified as the N-S plane, indicating the direction of rupture propagation. Source parameter estimation utilizing the EGF method revealed larger corner frequencies and stress drops compared to individual spectra estimation, attributed to the method’s improved correction for attenuation and site effects, without the need for simplified a priori models. Despite its low magnitude, the 2014 Arzew earthquake provided valuable insights into the region’s seismic behavior, contributing significantly to ground motion predictions. In particular, the study highlights the necessity of accounting for rupture directivity in seismic hazard assessments and mitigation strategies.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 4","pages":"951 - 972"},"PeriodicalIF":1.6,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507402","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
Earthquake detection capacity of the Dense Oceanfloor Network system for Earthquakes and Tsunamis (DONET) 地震和海啸密集洋底网络系统(DONET)的地震探测能力
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-06-06 DOI: 10.1007/s10950-024-10219-2
K. Z. Nanjo, Y. Yamamoto, K. Ariyoshi, H. Horikawa, S. Yada, N. Takahashi
{"title":"Earthquake detection capacity of the Dense Oceanfloor Network system for Earthquakes and Tsunamis (DONET)","authors":"K. Z. Nanjo,&nbsp;Y. Yamamoto,&nbsp;K. Ariyoshi,&nbsp;H. Horikawa,&nbsp;S. Yada,&nbsp;N. Takahashi","doi":"10.1007/s10950-024-10219-2","DOIUrl":"10.1007/s10950-024-10219-2","url":null,"abstract":"<div><p>We studied the earthquake detection capacity of DONET (Dense Oceanfloor Network system for Earthquakes and Tsunamis) operating in the Nankai Trough, a target region monitored for future megathrust earthquakes. The focus of this paper was to evaluate the impact on this capacity from the malfunction of parts of the network. For this purpose, the completeness magnitude, above which all earthquakes are considered to be detected by a seismic network, was used. Then, a catalog that includes events observed by DONET was used. We found spatiotemporal variability of completeness magnitude, ranging from values below 1 in one of the areas where stations are densely deployed to values above 2 at the periphery and outside of the DONET area. We conducted a simulation computation for cases of malfunction of densely distributed stations. The results showed that completeness estimates in the area near the malfunctioning stations were about 1 magnitude larger. This implies that malfunction repair and/or replacement with new stations would be desirable because they pronouncedly affect earthquake monitoring. We then demonstrated an example of how to use the information of completeness magnitude as prior knowledge to compute the <i>b</i> value of the Gutenberg-Richter distribution. The result indicates the <i>b</i> value as a proxy that can help to image stress heterogeneity when there is a magnitude-6 class slow slip event on the Nankai Trough plate boundary.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":"28 3","pages":"787 - 810"},"PeriodicalIF":1.6,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10950-024-10219-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141552551","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
Significance of VP/VS ratio in locating earthquakes of a long-duration swarm in the western coast of India VP/VS 比率在印度西海岸长持续时间地震群定位中的意义
IF 1.6 4区 地球科学
Journal of Seismology Pub Date : 2024-06-05 DOI: 10.1007/s10950-024-10223-6
Himangshu Paul, T. C. Sunilkumar, Vineet K. Gahalaut, D. Srinagesh, M. Shekar
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