It's only happened once in history that we know of, but a tsunami did once travel up the Mississippi River in Missouri and by the time it was done, 30 boats were no more.
Something strange is happening in southeastern Illinois. After 2 earthquakes struck the region yesterday, another slightly larger quake has just been reported and it also was widely felt.
There are new warnings about the possibility of a major earthquake on the New Madrid Fault, but when you look at the details you'll realize it's really nothing new that we don't already know.