We just learned about the Megathrust Earthquake, the earth's most powerful type of quake.
Another type of earthquake is the Remotely Triggered Earthquake.
Sometimes when one earthquake is large enough, it's mainshock or aftershock can cause other earthquakes.
But sometimes a bunch of earthquakes happen in one area within a few days or weeks of each other, but too far to be affected by the other earthquake's mainshock or aftershock.
This can be confusing, because if a bunch of earthquakes are happening in the same state, scientists want to know what is causing them all.
When a bunch of earthquakes happen close by but not close enough for aftershocks to cause it, these are the Remotely Triggered Earthquakes.
Many scientists think these are caused by things like magma or water flows underground, moving around and shifting the tectonic plates and causing the faults to become active and cause quakes.
(from: wikipedia - remotely triggered earthquakes)
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