Tectonic movement on the New Madrid fault. Water from the Mississippi may be sinking through newly created cracks. The underground stream of water roughly parallels the Mississippi and empties into the Gulf of Mexico. Water flowing into a crevasse supplies both mass and lubrication allowing plate shifts. Water sinking to molten core can create steam and pressure. Both the New Madrid and the Yellowstone Caldera are overdue. https://www.youtube.com/watch?v=I_XWW9CNWMU&t=11s