Have you heard of Lake Peigneur?

It was a lake on an island in Louisiana. Beneath was a salt mine and above it an exploratory drilling rig. The rig accidentally pierced the mines in the 80’s, creating a vortex that sunk the oil rig completely which was odd because the lake itself was only 10 feet deep. The water surging into the mines created such an intense vortex that it sunk barges, drained all the water, pulled some land surrounding the lake bed in and then sucked in water from a canal that led to the gulf back into it’s dry bed, creating the largest waterfall ever in Louisiana. Soon after, the water pressure displaced the air in the mines creating a loud boom and a 400 foot geyser that exploded from the entrance of the mine. In the aftermath, the lake became much, much deeper, went from freshwater to salt, and housed new marine life. No one died and 9 of 11 barges actually resurfaced from the vortex when it refilled with water.
FUCKING CRAZY.