Answer:
the plates that have just moved to create the first quake have to settle and in doing so create smaller but no less dangerous quakes called aftershocks.
There can be many episodes of ground-shaking movement in an earthquake caused by seismic waves. These are the energy waves that travel
outward from the source of the earthquake. These aftershocks are
actually smaller earthquakes, and they can cause damaged buildings to
collapse. The Kobe earthquake in Japan produced over 600 aftershocks.