A massive fault could trigger a cataclysmic earthquake beneath Bangladesh, parts of east India and Myanmar, new research suggests. The hidden fault, which has been buried under miles of river sediment, could release an earthquake of magnitude 8.2 to 9.0 in one of the most densely populated regions of the world, the study found. And because researchers discovered the system relatively recently, they have no estimates for when such a megaquake could occur. "We don't know if it's tomorrow or if it's not going to be for another 500 years," said study co-author Michael Steckler, a geophysicist at the Lamont-Doherty Earth Observatory at Columbia University in New York City. Hidden fault lines In the low-lying, waterlogged country of Bangladesh, the mighty Ganges and Brahmaputra rivers meet and form the world's largest delta, eventually draining into the Bay of Bengal. The flow of these two massive rivers deposits a gigaton of sediment every year, the researchers said. This constant overlay