The largest species of earthquake is classified as a megathrust earthquake, typically occurring at subduction zones where one tectonic plate is forced under another. These earthquakes can have a magnitude greater than 9.0 on the moment magnitude scale. A notable example is the 2004 Sumatra earthquake, which registered a magnitude of 9.1-9.3 and triggered a devastating tsunami. Megathrust earthquakes release immense energy and can cause widespread destruction across large coastal areas. Their impact can be felt for hundreds of kilometers and often leads to both direct damage and secondary effects, such as tsunamis.