Quake rerouted Ganges River: A similar event today could threaten 170 million people.

New geologic evidence suggests that the Ganges River in India and Bangladesh shifted abruptly around 2,500 years ago due to a distant earthquake. This shift occurred in the Ganges Delta, and if similar shifts were to occur in river deltas today, it could threaten hundreds of millions of people worldwide who live in low-lying areas. The researchers found a crescent-shaped depression that was likely a main channel of the Ganges in the past, and seismites, remnants of ancient sand volcanoes, which indicated the occurrence of a magnitude 7 or 8 earthquake about 2,500 years ago. The potential for similar shifts in the present poses a significant risk to infrastructure and adds to the threats of flooded deltas due to rising sea levels. [Extracted from the article]