Rupture process of rock mass including weak zones using three-dimensional discrete element method (3D-DEM)

PreviousNext No AccessProceedings of the 14th SEGJ International Symposium, Online, 18–21 October 2021Rupture process of rock mass including weak zones using three-dimensional discrete element method (3D-DEM)Authors: Kazuma OkadaSeiichiro KawaharaTada-nori GotoDaigo FurukawaSatoru YamaguchiKazuma OkadaUniversity of HyogoSearch for more papers by this author, Seiichiro KawaharaUniversity of HyogoSearch for more papers by this author, Tada-nori GotoUniversity of HyogoSearch for more papers by this author, Daigo FurukawaOsaka City UniversitySearch for more papers by this author, and Satoru YamaguchiOsaka City UniversitySearch for more papers by this authorhttps://doi.org/10.1190/segj2021-082.1 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract Experiments with three-dimensional (3D) analog and numerical rock mass models have been tested to clarify the geological evolution of active faults and the occurrence of earthquakes. The conventional studies modelled a simple crustal structure. However, the active fault distributions are complex and possibly affect the occurrence of earthquakes. For example, a main shock of a large earthquake often occurred near the bend of the fault zone (e.g., the 1995 Hyogo-ken Nanbu Earthquake in Japan). The relationship between rupture formation and earthquake occurrence around the complex active faults has not been discussed in previous laboratory and numerical experiments. Especially, the 3D digital modeling of crustal deformation is beneficial for integration of geographical, geological and geophysical data around active faults. In this study, we investigated how the rock mass including weak zones, which using numerical simulation. It has greater advantages than the laboratory experiments; the numerical simulation allows us to observe the internal deformations of rock mass. In this study, we simulated the strike-slip fault motion with a small-scale rock mass model using the 3D distinct element method (DEM). Various rock mass models were tested in this simulation. For example, we test whether the shape of the weak zone has a significant effect on the occurrence of an earthquake. The processes of ruptures propagations in two contrastive models are compared. Both models have a weak zone commonly; one model is characterized as a continuous bending weak zone, and another has a discontinuity (gap) of weak zone at the bending. As a result, it was found that the rupture process of the discontinuous model is similar to the main shock and aftershock sequence often observed such as at the 1995 Hyogo-ken Nanbu earthquake. Thus, the 3D-DEM simulation is effective to understand the rupture process along faults at earthquakes, and future data integration: e.g., among geophysical structure below the surface, seismic activities, and geodetical observations. Keywords: 3D-DEM, strike-slip fault, active fault model, Hyogo-ken Nanbu earthquakePermalink: https://doi.org/10.1190/segj2021-082.1FiguresReferencesRelatedDetails 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 Kazuma Okada, Seiichiro Kawahara, Tada-nori Goto, Daigo Furukawa, and Satoru Yamaguchi, (2021), "Rupture process of rock mass including weak zones using three-dimensional discrete element method (3D-DEM)," SEG Global Meeting Abstracts : 311-314. https://doi.org/10.1190/segj2021-082.1 Plain-Language Summary Keywords3D-DEMstrike-slip faultactive fault modelHyogo-ken Nanbu earthquakePDF DownloadLoading ...