The role of three-dimensional fault interactions in creating complex
seismic sequences and power-law magnitude distributions
Abstract
A physics-based earthquake simulator should reproduce first-order
empirical power-law behaviors of magnitudes and clustering. However,
sequences exhibiting these laws have only been produced in discrete and
low-dimension continuum simulations. We show that the same emergence
also occurs in 3-D continuum simulations. Our model approximates a
strike-slip fault system slipping under rate-and-state friction. We
produce spatiotemporally clustered earthquake sequences exhibiting
characteristic Gutenberg-Richter scaling as well as empirical
inter-event time distribution. With fault interaction, partial ruptures
emerge when seismogenic width W over characteristic nucleation length
Lā is larger than 16.24, but none occurs without fault
interaction. The mainshock recurrence times of individual faults remain
quasi-periodic and fit a Brownian passage time distribution. The system
mainshock recurrence time has a short-term Omori-type decay, indicating
a 22% chance of mainshock clustering. These results show that
physics-based multi-cycle models adequately reflect observed statistical
signatures and show practical potential for long-term hazard assessment
and medium-term forecasting.