We just learned about the Tsunami Earthquake that isn't very big but can trigger a tsunami.
Another type of earthquake is an Earthquake Swarm.
This is when a lot of earthquakes happen in the same area, and are clearly not just aftershocks or foreshocks from one single earthquake.
These can be hundreds or even over a thousand earthquakes in one state, spreading out over a time of days, weeks or months.
One of the ones that happened not long ago was in Nevada, with 1,000 earthquakes between February and November 2008.
(from: wikipedia - earthquake swarm)
Kid Facts - Blast from the past: Flux