Stochastic finite-fault method controlled by the fault rupture process
1Institute of Geophysics, Cna Earthquake Administration, Beijing, 100081, China.
Methodsx
|March 4, 2020
Summary
We improved the fault rupture simulation method (NNSIM) to better mimic real earthquake ground motion. This new method accurately reproduces strong ground motion across a wide frequency range, validated by the Lushan earthquake.
Area of Science:
- Earthquake seismology
- Computational geophysics
Background:
- Stochastic finite-fault methods are crucial for simulating earthquake ground motion.
- Accurate simulation requires incorporating physical fault rupture processes.
Purpose of the Study:
- To present an improved stochastic finite-fault method (NNSIM) that incorporates fault rupture physics.
- To enhance the simulation of strong ground motion across a broad frequency band.
Main Methods:
- Introducing the fault physical rupture process into the stochastic finite-fault method.
- Utilizing non-uniform time window functions and non-uniform stress drops.
- Validating the method against strong ground motion records from the Ms 7.0 Lushan earthquake.
Main Results:
- The NNSIM method produces simulated time series with varied shapes, unlike single-spindle shapes.
- Simulated pseudo-spectral acceleration (PSA), particularly the low-frequency component, is significantly improved.
- The simulated strong ground motion closely matches real ground motion from the Lushan earthquake.
Conclusions:
- The improved NNSIM method enhances the accuracy of simulated strong ground motion.
- Incorporating non-uniform rupture characteristics leads to more realistic ground motion simulations.
- The method is a valuable tool for seismic hazard analysis and earthquake engineering.
Keywords:
NNSIMNon-uniform stress drop distributionNon-uniform time functionThe stochastic finite-fault method controlled by the fault rupture processMore Related Videos
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