This video shows a simulation of a dynamic rupture model. The model is based on a postulated network of faults in the Salton Sea area, southern California. The hypocenter of this synthetic event is placed approximately 30km north of Bombay beach.
The first seconds of this simulation show the initiation phase of the earthquake, also known as the "nucleation phase".
After this initial phase, the earthquake rupture propagates spontaneously towards the right-hand side of the screen (south-east in the map). From that point on what we observe is the interaction between different faults in this system. More specifically, this animation highlights how the network of perpendicular faults (known as cross-faults) implemented in the middle of the domain affect the evolution of this synthetic earthquake.
The top two panels represent a different scenario than the bottom two panels. The difference between the top and bottom panels lies in the tendency of the cross-faults to participate in the rupture process, which is significantly higher in the second case. For that reason, in the bottom panels, we observe a cascade of cross-faults events that in the end will modulate the final magnitude of this specific model.