A team of French researchers led by geophysicist Yishuo Zhou has developed a computer model to study the impact of lunar and solar gravitational forces on geological faults. The study focuses on the mechanism behind slow earthquakes, which differ from standard seismic events by their extended duration.
The scientists utilized a spring-block system model to simulate fault movement, incorporating physical laws of friction that account for rock behavior during rest and motion. By applying periodic loads to mimic tidal influences, the team observed that the timing of these forces is critical to triggering seismic activity.
The researchers identified a resonance effect, comparing it to pushing a swing, where weak but rhythmic forces can amplify fault movement. The model demonstrated that specific combinations of force, frequency, and friction characteristics can transform stable fault sliding into a slow earthquake.
While the model is a simplified representation of real-world geological systems, it highlights how simple external triggers can lead to complex internal dynamics. The findings suggest that monitoring slow earthquakes in relation to tidal cycles may provide geologists with insights into the properties of deep faults.
