The Propagation of Local Undamped Motion (PLUM) Method: A Simple and Robust Seismic Wavefield Estimation Approach for Earthquake Early Warning

Abstract

Research Article| January 23, 2018 The Propagation of Local Undamped Motion (PLUM) Method: A Simple and Robust Seismic Wavefield Estimation Approach for Earthquake Early Warning Yuki Kodera; Yuki Kodera aMeteorological Research Institute, Japan Meteorological Agency, 1‐1 Nagamine, Tsukuba, Ibaraki 305‐0052, Japan, [e-mail], [e-mail], [e-mail] Search for other works by this author on: GSW Google Scholar Yasuyuki Yamada; Yasuyuki Yamada bSeismology and Volcanology Department, Japan Meteorological Agency, 1‐3‐4 Otemachi, Chiyoda‐ku, Tokyo 100‐8122, Japan, [e-mail], [e-mail], [e-mail], [e-mail] Search for other works by this author on: GSW Google Scholar Kazuyuki Hirano; Kazuyuki Hirano cOsaka Regional Headquarter, Japan Meteorological Agency, 4‐1‐76 Otemae, Chuo‐ku, Osaka 540‐0008, Japan, [e-mail] Search for other works by this author on: GSW Google Scholar Koji Tamaribuchi; Koji Tamaribuchi aMeteorological Research Institute, Japan Meteorological Agency, 1‐1 Nagamine, Tsukuba, Ibaraki 305‐0052, Japan, [e-mail], [e-mail], [e-mail] Search for other works by this author on: GSW Google Scholar Shimpei Adachi; Shimpei Adachi bSeismology and Volcanology Department, Japan Meteorological Agency, 1‐3‐4 Otemachi, Chiyoda‐ku, Tokyo 100‐8122, Japan, [e-mail], [e-mail], [e-mail], [e-mail] Search for other works by this author on: GSW Google Scholar Naoki Hayashimoto; Naoki Hayashimoto bSeismology and Volcanology Department, Japan Meteorological Agency, 1‐3‐4 Otemachi, Chiyoda‐ku, Tokyo 100‐8122, Japan, [e-mail], [e-mail], [e-mail], [e-mail] Search for other works by this author on: GSW Google Scholar Masahiko Morimoto; Masahiko Morimoto bSeismology and Volcanology Department, Japan Meteorological Agency, 1‐3‐4 Otemachi, Chiyoda‐ku, Tokyo 100‐8122, Japan, [e-mail], [e-mail], [e-mail], [e-mail] Search for other works by this author on: GSW Google Scholar Masaki Nakamura; Masaki Nakamura dResearch and Development Bureau, Ministry of Education, Culture, Sports, Science and Technology, 3‐2‐2 Kasumigaseki, Chiyoda‐ku, Tokyo 100‐8959, Japan, [e-mail] Search for other works by this author on: GSW Google Scholar Mitsuyuki Hoshiba Mitsuyuki Hoshiba aMeteorological Research Institute, Japan Meteorological Agency, 1‐1 Nagamine, Tsukuba, Ibaraki 305‐0052, Japan, [e-mail], [e-mail], [e-mail] Search for other works by this author on: GSW Google Scholar Bulletin of the Seismological Society of America (2018) 108 (2): 983–1003. https://doi.org/10.1785/0120170085 Article history first online: 23 Jan 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Yuki Kodera, Yasuyuki Yamada, Kazuyuki Hirano, Koji Tamaribuchi, Shimpei Adachi, Naoki Hayashimoto, Masahiko Morimoto, Masaki Nakamura, Mitsuyuki Hoshiba; The Propagation of Local Undamped Motion (PLUM) Method: A Simple and Robust Seismic Wavefield Estimation Approach for Earthquake Early Warning. Bulletin of the Seismological Society of America 2018;; 108 (2): 983–1003. doi: https://doi.org/10.1785/0120170085 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract A basic methodology for earthquake early warning is the use of point‐source models fed with observational data from triggered stations. The 2011 Off the Pacific Coast of Tohoku earthquake in Japan (⁠Mw 9.0) (the Tohoku‐Oki earthquake) and its aftershock and induced earthquake activity, however, highlighted the following technical challenges of point‐source models: (1) underprediction of the strong motion of large earthquakes with finite faults, (2) missing earthquakes during intense seismic activities, and (3) overprediction of the strong motion of multiple simultaneous earthquakes. We propose the propagation of local undamped motion (PLUM) method to address these technical challenges. The PLUM method is a simple wavefield‐estimation approach that predicts seismic intensities directly from observed real‐time seismic intensities near target sites. The PLUM method can outperform point‐source‐model approaches in terms of (a) accurate ground‐motion prediction for large earthquakes with finite faults and (b) robust event declaration for complex earthquake sequences. On the other hand, available warning times provided by the PLUM method are not expected to be very long. We also introduce a hybrid method that uses both the PLUM method and a point‐source‐model approach to maximize the total available warning times and avoid missing strong motion. When applied to the Tohoku‐Oki earthquake (⁠Mw 9.0), the PLUM and hybrid methods predicted accurate strong motion without underestimation and provided sufficient warning times in most areas. For the subsequent earthquake sequence after the Mw 9.0 earthquake, the PLUM method robustly detected and processed large earthquakes despite considerable intense seismicity. A statistical analysis using large aftershocks and induced earthquakes demonstrated that the PLUM and hybrid methods predicted strong motion more accurately than the point‐source‐model approach of the Japan Meteorological Agency. These findings indicate that the PLUM and hybrid methods can be effective countermeasures to address the technical challenges faced by point‐source models. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.