Benchmarking and evolving earthquake fault-rupture simulations

• Main Authors: Fülöp, Ludovic, Jussila, Vilho, Kaisko, Outi
• Format: Book
• Language: English
• Published: VTT Technical Research Centre of Finland 2023
• Subjects: earthquake rupture modelling; simulation; 3DEC; FLAC3D; Fennoscandian
• Online Access: https://cris.vtt.fi/en/publications/dbef5af6-825c-4f21-b070-253c5b3d6660; https://cris.vtt.fi/ws/files/102316440/VTT_R_00102_23_signed.pdf

Finland is located on the seismically quiet Fennoscandian shield with no modern-time observations of large earthquakes. The low level of seismicity has forced the nuclear facilities to conduct seismic hazard analyses with an insufficient amount or completely lacking relevant observations of surface or underground ground motions caused by earthquakes. The Finnish underground repositories suffer from even lesser data available as no observations on underground ground movements caused by earthquakes exist and therefore the analyses of underground earthquake hazard have been built solely on simulations (e.g., Hökmark et al., 2019). With recent advances in earthquake fault-rupture simulations, advanced software applications became available, and many publications were dedicated to simulating the rupture of earthquake faults (e.g., a review in IAEA, 2018). This development also led to large benchmarking exercises being conducted to compare the fault-rupture predictions of different software, and to compare these predictions with the limited observations available. In this work more agile simulation methodologies are proposed, and benchmarking based on the existing models is carried out. The existing methodology is quite laborious and computationally expensive. Benchmarking of suitable FEM-DEM/DEM code is given to large benchmarking exercises (e.g., published by Harris et al, 2018); confirming that the code is simulating the rupture of earthquake faults similarly to codes developed specifically for such applications.