It is time to submit nominations for the 2025 William B. Joyner Memorial Lecturer. Established by SSA in cooperation with the Earthquake Engineering Research Institute (EERI), these lectures honor Bill Joyner’s distinguished career at the U.S. Geological Survey and his abiding commitment to the exchange of information at the interface of earthquake science and earthquake engineering.Joyner Lecturers are chosen on the basis of their work at this interface, whether it involves contributions from earthquake science to earthquake engineering, or from earthquake engineering to earthquake science. Nominations can be made by any member of EERI or SSA, and the lecturer...
现在是提交 2025 年 William B. Joyner 纪念讲师提名的时候了。这些讲座由 SSA 与地震工程研究所 (EERI) 合作设立，旨在纪念 Bill Joyner 在美国地质调查局的杰出职业生涯，以及他对地震科学和地震工程界面信息交流的持久承诺。任何 EERI 或 SSA 成员均可提名，讲师...
{"title":"Nominations for the Next Joyner Lecturer Due 30 June","authors":"","doi":"10.1785/0220240178","DOIUrl":"https://doi.org/10.1785/0220240178","url":null,"abstract":"It is time to submit nominations for the 2025 William B. Joyner Memorial Lecturer. Established by SSA in cooperation with the Earthquake Engineering Research Institute (EERI), these lectures honor Bill Joyner’s distinguished career at the U.S. Geological Survey and his abiding commitment to the exchange of information at the interface of earthquake science and earthquake engineering.Joyner Lecturers are chosen on the basis of their work at this interface, whether it involves contributions from earthquake science to earthquake engineering, or from earthquake engineering to earthquake science. Nominations can be made by any member of EERI or SSA, and the lecturer...","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"27 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141513919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Seismic signals, whether caused by earthquakes, other natural phenomena, or artificial noise sources, have specific characteristics in the time and frequency domains that contain crucial information reflecting their source. The analysis of seismic time series is an essential part of every seismology‐oriented study program. Enabling students to work with data collected from their own campus, including signals from both anthropogenic and natural seismic sources, can provide vivid, practical examples to make abstract concepts communicated in classes more concrete and relevant. Data from research‐grade broadband seismometers enable us to record time series of vibrations at a broad range of frequencies; however, these sensors are costly and are often deployed in remote places. Participation in the Raspberry Shake citizen science network enables seismology educators to record seismic signals on our own campuses and use these recordings in our classrooms and for public outreach. Yale University installed a Raspberry Shake three‐component, low‐cost seismometer in the Earth and Planetary Sciences department building in Summer 2022, enabling the detection of local, regional, and teleseismic earthquakes, microseismic noise, and anthropogenic noise sources from building construction, an explosive event in a steam tunnel, and general building use. Here, we discuss and illustrate the use of data from our Raspberry Shake in outreach and education activities at Yale. In particular, we highlight a series of ObsPy‐based exercises that will be used in courses taught in our department, including our upper‐level Introduction to Seismology course and our undergraduate classes on Natural Disasters and Forensic Geoscience.
{"title":"Follow the Trace: Becoming a Seismo‐Detective with a Campus‐Based Raspberry Shake Seismometer","authors":"Eric Löberich, Maureen D. Long","doi":"10.1785/0220230365","DOIUrl":"https://doi.org/10.1785/0220230365","url":null,"abstract":"Seismic signals, whether caused by earthquakes, other natural phenomena, or artificial noise sources, have specific characteristics in the time and frequency domains that contain crucial information reflecting their source. The analysis of seismic time series is an essential part of every seismology‐oriented study program. Enabling students to work with data collected from their own campus, including signals from both anthropogenic and natural seismic sources, can provide vivid, practical examples to make abstract concepts communicated in classes more concrete and relevant. Data from research‐grade broadband seismometers enable us to record time series of vibrations at a broad range of frequencies; however, these sensors are costly and are often deployed in remote places. Participation in the Raspberry Shake citizen science network enables seismology educators to record seismic signals on our own campuses and use these recordings in our classrooms and for public outreach. Yale University installed a Raspberry Shake three‐component, low‐cost seismometer in the Earth and Planetary Sciences department building in Summer 2022, enabling the detection of local, regional, and teleseismic earthquakes, microseismic noise, and anthropogenic noise sources from building construction, an explosive event in a steam tunnel, and general building use. Here, we discuss and illustrate the use of data from our Raspberry Shake in outreach and education activities at Yale. In particular, we highlight a series of ObsPy‐based exercises that will be used in courses taught in our department, including our upper‐level Introduction to Seismology course and our undergraduate classes on Natural Disasters and Forensic Geoscience.","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"119 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141513918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We investigate the resolvability of a microseismic event location given a recording array composed of vertical distributed acoustic sensing (DAS) boreholes. We use a modified source‐scanning algorithm that takes into account both P and S waves. We transform the brightness maps it produces into probability density functions (PDFs), over which we carry out a resolution and uncertainty analysis. We apply this approach to microseismic events recorded by two vertical DAS boreholes as part of the Frontier Observatory for Research in Geothermal Energy (FORGE) project. We show that for the specific acquisition geometry in FORGE, the horizontal location of the events cannot be determined, but their depth can, similar to results obtained with a single borehole. Using synthetic examples, we show that the recording array’s geometry is the limiting factor in the determination of the horizontal location. We investigate various possible recording geometries composed of idealized DAS‐like vertical boreholes with varying locations and depths. We find that, besides the number of recordingd boreholes, their depth is the main factor influencing the location estimation uncertainty. The number and position of the boreholes mainly influence the spatial distribution of the PDF, whereas the boreholes’ depth mainly influences its size. Despite the simplicity of our analysis, it highlights the influence of the monitoring array design for microseismic events’ locating using vertical DAS arrays.
我们研究了由垂直分布式声学传感（DAS）钻孔组成的记录阵列对微地震事件位置的可分辨性。我们使用了一种改进的震源扫描算法，该算法同时考虑了 P 波和 S 波。我们将其生成的亮度图转换为概率密度函数 (PDF)，并对其进行分辨率和不确定性分析。我们将这种方法应用于地热能研究前沿观测站（FORGE）项目中由两个垂直 DAS 井眼记录的微地震事件。我们发现，对于 FORGE 项目中的特定采集几何形状，地震事件的水平位置无法确定，但其深度可以确定，这与单个钻孔获得的结果类似。通过合成实例，我们表明记录阵列的几何形状是确定水平位置的限制因素。我们研究了由不同位置和深度的理想化 DAS 型垂直钻孔组成的各种可能的记录几何结构。我们发现，除了记录钻孔的数量外，其深度也是影响位置估计不确定性的主要因素。钻孔的数量和位置主要影响 PDF 的空间分布，而钻孔深度则主要影响 PDF 的大小。尽管我们的分析很简单，但它强调了监测阵列设计对使用垂直 DAS 阵列进行微震事件定位的影响。
{"title":"Microseismic Event Location with Dual Vertical DAS Arrays: Insights from the FORGE 2022 Stimulation","authors":"Eyal Shimony, Ariel Lellouch","doi":"10.1785/0220230128","DOIUrl":"https://doi.org/10.1785/0220230128","url":null,"abstract":"We investigate the resolvability of a microseismic event location given a recording array composed of vertical distributed acoustic sensing (DAS) boreholes. We use a modified source‐scanning algorithm that takes into account both P and S waves. We transform the brightness maps it produces into probability density functions (PDFs), over which we carry out a resolution and uncertainty analysis. We apply this approach to microseismic events recorded by two vertical DAS boreholes as part of the Frontier Observatory for Research in Geothermal Energy (FORGE) project. We show that for the specific acquisition geometry in FORGE, the horizontal location of the events cannot be determined, but their depth can, similar to results obtained with a single borehole. Using synthetic examples, we show that the recording array’s geometry is the limiting factor in the determination of the horizontal location. We investigate various possible recording geometries composed of idealized DAS‐like vertical boreholes with varying locations and depths. We find that, besides the number of recordingd boreholes, their depth is the main factor influencing the location estimation uncertainty. The number and position of the boreholes mainly influence the spatial distribution of the PDF, whereas the boreholes’ depth mainly influences its size. Despite the simplicity of our analysis, it highlights the influence of the monitoring array design for microseismic events’ locating using vertical DAS arrays.","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"225 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141513987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jyun‐Yan Huang, Norman A. Abrahamson, Chih‐Hsuan Sung, Shu‐Hsien Chao
New global source‐scaling relations for the aspect ratio and rupture area for crustal earthquakes that include the width‐limited effect and a possible free‐surface effect are derived using a global dataset of finite‐fault rupture models. In contrast to the commonly used scaling relations between moment magnitude (M), fault length (L), width (W), and area, we built self‐consistent scaling relations by relating M to the aspect ratio (L/W) and to the fault area to model the change in the aspect ratio once the rupture width reaches the down‐dip width limit of the fault. The width‐limited effect of large‐magnitude earthquakes depends on the fault dip and a regional term for the seismogenic thickness. The magnitude scaling of the aspect ratio includes a break in the magnitude scaling that is dip angle dependent. This dip angle‐dependent magnitude scaling in the magnitude–area relation is modeled by a trilinear relation incorporating a dip‐related transition range. The effect of the free surface was observed using a normalized depth term and parameterizing the source by the depth of the top of the fault rupture; it is more apparent in the area scaling relation. The scaling differences are related to the fault geometry, not to the rake angle, as commonly assumed. Finally, the corresponding L and W scaling relations obtained by converting the area and aspect ratio models to L and W models not only show good agreement with the previous regional scaling laws on average but also provide better fault‐specific application due to the inclusion of a fault‐specific dip angle and seismogenic thickness.
利用有限断层破裂模型的全球数据集，得出了包括宽度限制效应和可能的自由表面效应在内的地壳地震长宽比和破裂面积的新的全球震源缩放关系。与常用的力矩震级（M）、断层长度（L）、宽度（W）和面积之间的比例关系不同，我们通过将 M 与高宽比（L/W）和断层面积联系起来，建立了自洽的比例关系，以模拟一旦破裂宽度达到断层下倾宽度极限时高宽比的变化。大震级地震的宽度限制效应取决于断层倾角和区域性成震厚度。纵横比的震级缩放包括与倾角有关的震级缩放断裂。震级-面积关系中这种与倾角相关的震级缩放关系是通过一个包含与倾角相关的过渡范围的三线关系来模拟的。使用归一化深度项和以断层破裂顶部深度为参数的震源，可以观察到自由表面的影响；这在面积缩放关系中更为明显。缩放差异与断层的几何形状有关，而不是像通常假设的那样与倾斜角有关。最后，通过将面积和长宽比模型转换为 L 和 W 模型而得到的相应 L 和 W 缩放关系不仅在平均水平上与之前的区域缩放规律显示出良好的一致性，而且由于包含了特定断层的倾角和震源厚度，还提供了更好的特定断层应用。
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Ettore Biondi, Jorge C. Castellanos, Robert W. Clayton
The identification of preexisting near‐surface faults represents a piece of crucial information needed to correctly assess the seismic hazard of any area. The mapping of these structures is particularly challenging in densely populated and heavily urbanized areas. We use ambient seismic noise recorded by a dense array in Seal Beach, California, to image shallow fault lines via a reflected surface‐wave analysis. Our results highlight the presence of previously unknown shallow faults that correlate remarkably well with shallow seismicity and active survey images.
{"title":"Imaging Urban Hidden Faults with Ambient Noise Recorded by Dense Seismic Arrays","authors":"Ettore Biondi, Jorge C. Castellanos, Robert W. Clayton","doi":"10.1785/0220230408","DOIUrl":"https://doi.org/10.1785/0220230408","url":null,"abstract":"The identification of preexisting near‐surface faults represents a piece of crucial information needed to correctly assess the seismic hazard of any area. The mapping of these structures is particularly challenging in densely populated and heavily urbanized areas. We use ambient seismic noise recorded by a dense array in Seal Beach, California, to image shallow fault lines via a reflected surface‐wave analysis. Our results highlight the presence of previously unknown shallow faults that correlate remarkably well with shallow seismicity and active survey images.","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"216 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141513986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Francesco Pintori, Federica Sparacino, Federica Riguzzi
We analyze the interplay between hydrology, deformation, and seismicity in the Matese massif, located in the Italian Southern Apennines. We find that this area is characterized by the concurrent action of two hydrologically driven processes: the first is the deformation detected by the Global Navigation Satellite Systems (GNSS) data in the shallowest part (above the elevation of the major springs) of the Earth crust, in phase with the hydrological forcing; the second is the triggering of seismicity at depth with a delay suggesting a downward diffusive process. We study the first process by applying a principal component analysis to the GNSS displacements time series, aiming to identify a common signal describing the largest data variance. We find that the maximum horizontal displacements associated with the first principal component (PC1) are larger than 1 cm in two GNSS sites, and the PC1 temporal evolution is well correlated and in phase with the flow of the largest spring of the region, which we consider as proxy of the water content of the massif. This suggests that the main source of horizontal deformation is the water content fluctuations in the shallow portion of the Matese aquifer, in particular within fractures located in correspondence of the main mapped faults. The deformation rates caused by this process are one order of magnitude larger than the tectonic ones. Finally, we infer the second process by observing the correlation between the background seismicity and the spring discharge with a time lag of 121 days. In our interpretation, downward diffusive processes, driven by aquifer water content variations, propagate pore‐pressure waves that affect the fault’s strength favoring the occurrence of microearthquakes. This is supported by the values of hydraulic diffusivity (1.5 m2/s) and rock permeability (3.2–3.8×10−13 m2), which are compatible with what is observed in karstified limestones.
{"title":"Hydrology Drives Crustal Deformation and Modulates Seismicity in the Matese Massif (Italy)","authors":"Francesco Pintori, Federica Sparacino, Federica Riguzzi","doi":"10.1785/0220230239","DOIUrl":"https://doi.org/10.1785/0220230239","url":null,"abstract":"We analyze the interplay between hydrology, deformation, and seismicity in the Matese massif, located in the Italian Southern Apennines. We find that this area is characterized by the concurrent action of two hydrologically driven processes: the first is the deformation detected by the Global Navigation Satellite Systems (GNSS) data in the shallowest part (above the elevation of the major springs) of the Earth crust, in phase with the hydrological forcing; the second is the triggering of seismicity at depth with a delay suggesting a downward diffusive process. We study the first process by applying a principal component analysis to the GNSS displacements time series, aiming to identify a common signal describing the largest data variance. We find that the maximum horizontal displacements associated with the first principal component (PC1) are larger than 1 cm in two GNSS sites, and the PC1 temporal evolution is well correlated and in phase with the flow of the largest spring of the region, which we consider as proxy of the water content of the massif. This suggests that the main source of horizontal deformation is the water content fluctuations in the shallow portion of the Matese aquifer, in particular within fractures located in correspondence of the main mapped faults. The deformation rates caused by this process are one order of magnitude larger than the tectonic ones. Finally, we infer the second process by observing the correlation between the background seismicity and the spring discharge with a time lag of 121 days. In our interpretation, downward diffusive processes, driven by aquifer water content variations, propagate pore‐pressure waves that affect the fault’s strength favoring the occurrence of microearthquakes. This is supported by the values of hydraulic diffusivity (1.5 m2/s) and rock permeability (3.2–3.8×10−13 m2), which are compatible with what is observed in karstified limestones.","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"19 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140803271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study develops data‐driven global and region‐specific ground‐motion models (GMMs) for subduction earthquakes using a weighted average ensemble model to combine four different nonparametric supervised machine‐learning (ML) algorithms, including an artificial neural network, a kernel ridge regressor, a random forest regressor, and a support vector regressor. To achieve this goal, we train individual models using a subset of the Next Generation Attenuation‐Subduction (NGA‐Sub) data set, including 9559 recordings out of 153 interface and intraslab earthquakes recorded at 3202 different stations. A grid search is used to find each model’s best hyperparameters. Then, we use an equally weighted average ensemble approach to combine these four models. Ensemble modeling is a technique that combines the strengths of multiple ML algorithms to mitigate their weaknesses. The ensemble model considers moment magnitude (M), rupture distance (Rrup), time‐averaged shear‐wave velocity in the upper 30 m (VS30), and depth to the top of the rupture plane (Ztor), as well as tectonic and region as input parameters, and predicts various median orientation‐independent horizontal component ground‐motion intensity measures such as peak ground displacement, peak ground velocity, peak ground acceleration, and 5%‐damped pseudospectral acceleration values at spectral periods of 0.01–10 s in log scale. Although no functional form is defined, the response spectra and the distance and magnitude scaling trends of the weighted average ensemble model are consistent and comparable with the NGA‐Sub GMMs, with slightly lower standard deviations. A mixed effects regression analysis is used to partition the total aleatory variability into between‐event, between‐station, and event‐site‐corrected components. The derived global GMMs are applicable to interface earthquakes with M 4.9–9.12, 14≤Rrup≤1000 km, and Ztor≤47 km for sites having VS30values between 95 and 2230 m/s. For intraslab events, the derived global GMMs are applicable to M 4.0–8.0, 28≤Rrup≤1000 km, and 30≤Ztor≤200 km for sites having VS30 values between 95 and 2100 m/s.
本研究使用加权平均集合模型，结合四种不同的非参数监督机器学习（ML）算法，包括人工神经网络、核脊回归器、随机森林回归器和支持向量回归器，为俯冲地震开发数据驱动的全球和特定区域地动模型（GMM）。为了实现这一目标，我们使用下一代衰减-减弱（NGA-Sub）数据集的子集来训练各个模型，其中包括在 3202 个不同站点记录的 153 次界面和实验室内地震中的 9559 次记录。我们使用网格搜索来找到每个模型的最佳超参数。然后，我们使用加权平均集合方法来组合这四个模型。集合建模是一种结合多种 ML 算法的优点以减轻其缺点的技术。集合模型将力矩大小（M）、断裂距离（Rrup）、上部 30 米的时间平均剪切波速度（VS30）、到断裂面顶部的深度（Ztor）以及构造和区域作为输入参数，并预测各种与方位无关的水平分量地动强度中值，如地表位移峰值、地表速度峰值、地表加速度峰值以及频谱周期为 0.01-10 秒的对数标度。虽然没有定义函数形式，但加权平均集合模型的响应谱以及距离和幅度缩放趋势与 NGA-Sub GMMs 一致并具有可比性，标准偏差略低。通过混合效应回归分析，将总的人工变异性划分为事件间、站点间和事件-站点校正部分。推导出的全球 GMM 适用于 VS30 值在 95 至 2230 m/s 之间的站点，M 值为 4.9-9.12、14≤Rrup≤1000 km 和 Ztor≤47 km 的界面地震。对于台内事件，得出的全球 GMM 适用于 M 4.0-8.0、28≤Rrup≤1000 km 和 30≤Ztor≤200 km（VS30 值在 95 至 2100 m/s 之间）的站点。
{"title":"Ensemble Region‐Specific GMMs for Subduction Earthquakes","authors":"Farhad Sedaghati, Shahram Pezeshk","doi":"10.1785/0220230070","DOIUrl":"https://doi.org/10.1785/0220230070","url":null,"abstract":"This study develops data‐driven global and region‐specific ground‐motion models (GMMs) for subduction earthquakes using a weighted average ensemble model to combine four different nonparametric supervised machine‐learning (ML) algorithms, including an artificial neural network, a kernel ridge regressor, a random forest regressor, and a support vector regressor. To achieve this goal, we train individual models using a subset of the Next Generation Attenuation‐Subduction (NGA‐Sub) data set, including 9559 recordings out of 153 interface and intraslab earthquakes recorded at 3202 different stations. A grid search is used to find each model’s best hyperparameters. Then, we use an equally weighted average ensemble approach to combine these four models. Ensemble modeling is a technique that combines the strengths of multiple ML algorithms to mitigate their weaknesses. The ensemble model considers moment magnitude (M), rupture distance (Rrup), time‐averaged shear‐wave velocity in the upper 30 m (VS30), and depth to the top of the rupture plane (Ztor), as well as tectonic and region as input parameters, and predicts various median orientation‐independent horizontal component ground‐motion intensity measures such as peak ground displacement, peak ground velocity, peak ground acceleration, and 5%‐damped pseudospectral acceleration values at spectral periods of 0.01–10 s in log scale. Although no functional form is defined, the response spectra and the distance and magnitude scaling trends of the weighted average ensemble model are consistent and comparable with the NGA‐Sub GMMs, with slightly lower standard deviations. A mixed effects regression analysis is used to partition the total aleatory variability into between‐event, between‐station, and event‐site‐corrected components. The derived global GMMs are applicable to interface earthquakes with M 4.9–9.12, 14≤Rrup≤1000 km, and Ztor≤47 km for sites having VS30values between 95 and 2230 m/s. For intraslab events, the derived global GMMs are applicable to M 4.0–8.0, 28≤Rrup≤1000 km, and 30≤Ztor≤200 km for sites having VS30 values between 95 and 2100 m/s.","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"123 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140803334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Seismological Society of America (SSA) topical conference, Future Directions for Physics‐Based Ground Motion Modeling, was held in Vancouver, Canada, on 10–13 October 2023, co‐sponsored by the Seismological Society of Japan and co‐chaired by Annemarie Baltay of the U.S. Geological Survey and Hiroshi Kawase of Kyoto University. This meeting brought together many researchers and practitioners interested in modeling, observing, and utilizing ground‐motion models (GMMs). Scientists gathered to discuss complex kinematic and dynamic rupture simulation approaches, empirical representations of the earthquake source, site and path effects, physical modeling of the recording site, challenges for model extrapolation, and overall prediction accuracy and...
{"title":"Summary of the Discussions During the 2023 SSA Topical Meeting on “Future Directions for Physics‐Based Ground Motion Modeling”","authors":"Hiroshi Kawase, Annemarie Baltay","doi":"10.1785/0220240084","DOIUrl":"https://doi.org/10.1785/0220240084","url":null,"abstract":"The Seismological Society of America (SSA) topical conference, Future Directions for Physics‐Based Ground Motion Modeling, was held in Vancouver, Canada, on 10–13 October 2023, co‐sponsored by the Seismological Society of Japan and co‐chaired by Annemarie Baltay of the U.S. Geological Survey and Hiroshi Kawase of Kyoto University. This meeting brought together many researchers and practitioners interested in modeling, observing, and utilizing ground‐motion models (GMMs). Scientists gathered to discuss complex kinematic and dynamic rupture simulation approaches, empirical representations of the earthquake source, site and path effects, physical modeling of the recording site, challenges for model extrapolation, and overall prediction accuracy and...","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"23 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140803337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"SSA 2024 Annual Meeting","authors":"","doi":"10.1785/0220240136","DOIUrl":"https://doi.org/10.1785/0220240136","url":null,"abstract":"Abstract not available","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"12 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140628005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The 95th Annual Meeting of the Eastern Section of the Seismological Society of America (ES‐SSA) was held on 22–24 October 2023. The meeting was held in person at Southern Methodist University (SMU) in Dallas, Texas. Just over 80 people registered for the meeting and attended oral sessions over two days (Fig. 1). We held six oral sessions with 35 presentations and had two blocks of time to view and discuss 28 posters, which remained on display during the entire meeting.On Sunday, 22 October 2023, a field trip to explore the Wichita Mountains and the Meers Fault in Oklahoma....
{"title":"2023 Eastern Section SSA Annual Meeting Report 22–24 October 2023","authors":"","doi":"10.1785/0220230428","DOIUrl":"https://doi.org/10.1785/0220230428","url":null,"abstract":"The 95th Annual Meeting of the Eastern Section of the Seismological Society of America (ES‐SSA) was held on 22–24 October 2023. The meeting was held in person at Southern Methodist University (SMU) in Dallas, Texas. Just over 80 people registered for the meeting and attended oral sessions over two days (Fig. 1). We held six oral sessions with 35 presentations and had two blocks of time to view and discuss 28 posters, which remained on display during the entire meeting.On Sunday, 22 October 2023, a field trip to explore the Wichita Mountains and the Meers Fault in Oklahoma....","PeriodicalId":21687,"journal":{"name":"Seismological Research Letters","volume":"6 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139924298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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