The last major quake felt along the New Madrid, was in the 1800s. Someone told me once it actually reversed the course of the Big Muddy..
Not only that, but it rang churchbells in Boston and woke up Thomas Jefferson. There's a chapter on this in a book called "Big Muddy," that came out 10-15 years ago. It was a hellish situation. Fortunately, there were not a lot of people in the area at the time. About 10 years ago, a scientist predicted that a quake would occur on the Monday after Thanksgiving. I was visting the St. Louis area at the time, and a lot of the folks around there expected it to happen. Some kept their kids home from school.
That earthquake created Reelfoot Lake.
It did indeed make the Mississippi flow backward for a brief time. Additionally, the quake caused the spontaneous formation of Reelfoot Lake in TN.
it did reverse the flow of the mississippi and created realfoot lake in tenn.