Estimation of the seismogenic layer in the source region of the 2008 Iwate-Miyagi Nairiku earthquake based on the redetermination of source distribution by using Hi-net data

PreviousNext No AccessProceedings of the 14th SEGJ International Symposium, Online, 18–21 October 2021Estimation of the seismogenic layer in the source region of the 2008 Iwate-Miyagi Nairiku earthquake based on the redetermination of source distribution by using Hi-net dataAuthors: Takanobu SatoHiroaki SatoTakanobu SatoCentral Research Institute of Electric Power IndustrySearch for more papers by this author and Hiroaki SatoCentral Research Institute of Electric Power IndustrySearch for more papers by this authorhttps://doi.org/10.1190/segj2021-023.1 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract The depths of the upper and lower limits of the seismogenic layer are important for evaluating earthquake ground motions. However, since the seismogenic layer is deeper than the seismic basement in the uppermost crust, it is often difficult to carry out geophysical explorations. Therefore, the D10 and the D90 depths estimated from the small earthquakes distribution by the JMA earthquake catalog play the important role of identification of the seismogenic layer. In this study, to improve the accuracy of the source distribution by using Hi-net data by NIED, we redetermine the source distribution of the 2008 Iwate-Miyagi Nairiku earthquake source region. We select 7,424 earthquakes which occurred in the source region and apply the homogeneous station method and the double-difference method to redetermine the accurate seismic source distribution. As a result, the seismogenic layer becomes shallower and thinner after the source redetermination. To focus on the source distribution, focal depths are estimated to be shallow in the southern area, and the different dip angles are suggested in the northern area and the southern area. Furthermore, we also discuss the effect of the assumed velocity structure model used in the source location determination on the estimated seismic source distribution. Keywords: 2008 Iwate-Miyagi Nairiku earthquake, seismogenic layer, D10 D90, homogeneous station method, double-difference method, NIED Hi-netPermalink: https://doi.org/10.1190/segj2021-023.1FiguresReferencesRelatedDetails Proceedings of the 14th SEGJ International Symposium, Online, 18–21 October 2021ISSN (online):2159-6832Copyright: 2021 Pages: 349 publication data© 2021 Published in electronic format with permission by the Society of Exploration Geophysicists of JapanPublisher:Society of Exploration GeophysicistsSociety of Exploration Geophysicists of Japan HistoryPublished Online: 29 Nov 2021 CITATION INFORMATION Takanobu Sato and Hiroaki Sato, (2021), "Estimation of the seismogenic layer in the source region of the 2008 Iwate-Miyagi Nairiku earthquake based on the redetermination of source distribution by using Hi-net data," SEG Global Meeting Abstracts : 83-86. https://doi.org/10.1190/segj2021-023.1 Plain-Language Summary Keywords2008 Iwate-Miyagi Nairiku earthquakeseismogenic layerD10 D90homogeneous station methoddouble-difference methodNIED Hi-netPDF DownloadLoading ...