SCEC2024 Poster #002: High-frequency energy radiation controlled by the rupture complexity

Group B, Poster #002, Seismology

High-frequency energy radiation controlled by the rupture complexity

Poster Image:

Poster Presentation

2024 SCEC Annual Meeting, Poster #002, SCEC Contribution #13503 VIEW PDF

Since its introduction to seismology in the 1960s, the seismic moment (M_0) has become the most crucial and reliable earthquake source parameter. While the seismic moment determined using long-period waves is less affected by a source’s structural complexities, the energy of high-frequency seismic waves (E_HF) is challenging to interpolate using a simple plane rupture model. The ratio between E_HF and M_0 can vary significantly among different earthquakes and is potentially influenced by multiple factors, such as magnitude and types of faulting. Understanding the interaction between structural complexity and high-frequency energy excitation is essential for analyzing earthquake source proper...ties and hazard assessment. In this study, we quantitatively evaluate the complexity of rupture using finely relocated aftershock catalogs following large strike-slip events. We demonstrate that the defined complexity is a measure of the fault's fractal properties. The strong positive correlation between fault complexities and E_HF/M_0 ratios in large strike-slip events suggests that the fractal dimension of faults may control the high-frequency radiation efficiency. Our results underscore the importance of investigating source-region structure in earthquake science.
SHOW MORE